06/27/2025 Forecast Update

FORECAST SUMMARY: Monday, June 27, 2025, through Monday, June 30, 2025

OZONE: 8-hour average Ozone concentrations are expected to mostly range between Good (AQI Green) and Moderate (AQI Yellow). 

PM-2.5:  24-hour average Fine Particulate concentrations are expected to range from Good (AQI Green) to Moderate (AQI Yellow). 

FORECAST DISCUSSION

Fortunately, this weekend will not be a repeat of last weekend’s blistering hot weather.  For Friday, however, humid conditions are already in place with most sites reporting dewpoints in the low 70s.  Nearly all model guidance brings high temperatures today to around 90 degrees.  Model guidance also supports a potential outbreak of storms during late afternoon/early evening with localized downpours and damaging winds as a cold front passes through.  Up to two inches of rain could fall in localized downpour regions.

Saturday will be nice payback for the miserable conditions of last weekend.  For one day, we will be in a west-northwest wind flow, with comfortable temperatures around 80 degrees, low dewpoints around 60 degrees, comfortable wind speeds under 10 mph, and mostly sunny skies.  Saturday will definitely be the day to be outside enjoying the weather.  Air Quality will follow suit with conditions expected in the Good range.

Sunday will return to warmer, more humid conditions as a warm front passes and puts us back into the warm air sector of approaching cold front.  Temperatures will rise back into the upper-80’s/low-90’s, dewpoints into the mid-60’s, and higher misery index.  Air Quality is expected to deteriorate, but all indications are that the west side of Lake Michigan would see the worst of it.  Areas north of Detroit could see some spotty higher numbers but I am not expecting anything worse than High Moderate.

Sunday’s warmup will be short-lived as the above mentioned cold front tracks through the region Monday night/Tuesday morning providing the potential for additional thunderstorm chances.  Following this front is finally the much-anticipated air mass change we have been seeking with cooler, dryer, mostly smoke-free Canadian air entering the region.   This should alleviate any Air Quality issues for the next few days.

  EXTENDED FORECAST:

 Air Quality is not expected to be an issue, during the upcoming work week, with lower temperatures and humidity.

06/23/2025 Forecast Update

FORECAST SUMMARY: Monday, June 23, 2025, through Friday, June 27, 2025

 Air Quality Advisory Remains in Effect for Monday, June 23, 2025

 The Michigan Department of Environment, Great Lakes, and Energy (EGLE) is continuing an Air Quality Advisory for June 23, 2025, for elevated levels of ozone in western counties of Michigan. Pollutants within those areas are expected to be in the Unhealthy for Sensitive Groups (USG, AQI Orange) range.

 The Air Quality Advisory for Monday is in effect for the following Michigan counties:

 Allegan, Berrien, Cass, Kent, Mason, Muskegon, Oceana, Ottawa, and Van Buren

  OZONE: 8-hour average Ozone concentrations are expected to mostly range between Good (AQI Green) and Moderate (AQI Yellow).  An Air Quality Advisory remains in effect during Monday where conditions could reach Unsafe for Sensitive Groups (USG, AQI Orange) in several western lake shore counties.

 PM-2.5:  24-hour average Fine Particulate concentrations are expected to range from Good (AQI Green) to Moderate (AQI Yellow). 

  FORECAST DISCUSSION

 For those who complained that summer was slow to arrive, the past weekend should put that complaint to rest.  Temperatures in excess of 90 degrees and dew points hovering around 70 degrees kept the misery index near 100 degrees, despite breezy conditions.  That trend will persist through Monday. 

 The main player for the weather, this week, will be a cold front currently extending from northwest Wisconsin down to the four corners area in the southwest USA.  That front is expected to slowly drop through Michigan during Tuesday and stall out around the Michigan/Indiana border.  While this will provide some minor heat relief, we not expecting any real air mass change.  Conditions will remain humid with dew points near 70 with daytime temperatures in the mid to upper 80’s.  The stalled front will also act as a focus for shower and thunderstorm development during the Tuesday-Friday timeframe.  Conditions could be favorable for strong to severe storms.  That front is then expected to lift north, during Friday, as a warm front.

 In terms of Air Quality, we have actually been fortunate up to this point.  Although an Air Quality Advisory remains in effect for Monday, high dew points have a tendency to reduce ozone potential, and the weekend’s high humidity has helped stunt elevated growth.  As the before-mentioned front approaches and arrives during Tuesday, the expected cloud cover and rain potential, as well as continued high humidity, should keep conditions no worse than Moderate for the next few days.

 Saturday appears to be the first day for clearer skies with still hot temperatures and slightly less humidity with dew points in the mid/upper-60’s.  We will be in the same potentially dirty air mass, however, and the weekend forecast will be updated on Friday to access the potential for elevated ozone.  Long ranges models are indicating that the first real change in air mass will not occur until around Tuesday of next week.

  EXTENDED FORECAST:

 Air Quality could be an issue, during the upcoming weekend, with continued heat and slightly less humidity.

Next forecast update: Friday, June 27, 2025

06/22/2025 Forecast Update

FORECAST SUMMARY: Sunday, June 22, 2025 - Monday, June 23, 2025

Ozone: 8-hour ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI), with USG (Orange, AQI) possible along the west Michigan lakeshore.

PM-2.5: 24-hour daily average Fine Particulate concentrations will range between upper Good and Moderate.

Air Quality Advisory for Sunday, June 22, and Monday, June 23, 2025

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) has declared an Air Quality Advisory for June 22 and June 23, 2025, for elevated levels of ozone in western counties of Michigan. Pollutants within those areas are expected to be in the Unhealthy for Sensitive Groups (USG, Orange AQI) range.

The Air Quality Advisory for Sunday is in effect for the following Michigan counties:

Allegan, Antrim, Benzie, Berrien, Cass, Charlevoix, Emmet, Grand Traverse, Kent, Leelanau, Manistee, Mason, Muskegon, Oceana, Ottawa, and Van Buren

The Air Quality Advisory for Monday is in effect for the following Michigan counties:

Allegan, Berrien, Cass, Kent, Mason, Muskegon, Oceana, Ottawa, and Van Buren

FORECAST DISCUSSION:

Hot temperatures and humidity continue to be the main forecast points as we move into the new week. Temperatures in the 90s, along with high humidity, remain in place, making it “feel” like 100+ degrees in parts of the state. Those with outside plans should exercise caution. Plentiful sunshine coupled with southwest winds and a warm surface and upper-level flow creates an environment favorable for ozone development. However, one component against ozone development is the high humidity in place. Increased levels of humidity can work against ozone development, even when ample sunshine is expected. There is enough threat of increased ozone along the western shoreline of Lake Michigan to warrant a continuation of an Air Quality Advisory for Sunday. The threat lingers through Monday for locations south of Ludington. However, ozone concentrations across the rest of the state should be no higher than Moderate.

By Monday, a cold front will be dropping in from the north, bringing clouds and chances for storms across the northern parts of the state. This setup will improve ozone levels further north, but ozone-conducive conditions will continue south. While increases across much of the state should not be higher than Moderate, the threat for USG ozone lingers across the central and southern western lakeshore areas; therefore, the air quality advisory for ozone has been extended through Monday for Ludington, south to the state border.

As expected, PM2.5 concentrations have slowly increased the past few days, and this trend is expected to continue. Daily averages are not expected to exceed the low to middle Moderate range.

EXTENDED FORECAST:

Extended models show the heat and humidity lingering into next week, and chances for precipitation come into play as well. This forecast will be updated Monday to determine if air quality advisories are needed later in the forecast period.

 Next Forecast update: Monday, June 23, 2025

06/21/2025 Forecast Update

FORECAST SUMMARY: Saturday, June 21, 2025 - Sunday, June 22, 2025

Ozone: 8-hour ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI), with USG (Orange, AQI) possible along the west Michigan lakeshore.

PM-2.5: 24-hour daily average Fine Particulate concentrations will range between upper Good and Moderate.

Air Quality Advisory for Saturday, June 21, and Sunday, June 22, 2025

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) has declared an Air Quality Advisory for June 21 and June 22, 2025, for elevated levels of ozone in western counties of Michigan. Pollutants within those areas are expected to be in the Unhealthy for Sensitive Groups (USG, Orange AQI) range.

The Air Quality Advisory for Saturday is in effect for the following Michigan counties:

Allegan, Berrien, Cass, Kent, Muskegon, Ottawa, and Van Buren

The Air Quality Advisory for Sunday is in effect for the following Michigan counties:

Allegan, Antrim, Benzie, Berrien, Cass, Charlevoix, Emmet, Grand Traverse, Kent, Leelanau, Manistee, Mason, Muskegon, Oceana, Ottawa, and Van Buren

FORECAST DISCUSSION:

Hot temperatures and humidity continue to be the main forecast points for this weekend into early next week. Temperatures in the 90s, along with increased humidity, will make it “feel” like 100+ degrees in parts of the state. Those with outside plans should exercise caution. Storms and clouds in northern and eastern portions of the state on Saturday should keep ozone from increasing significantly in those locations. However, with ample sunshine expected in the southwest, along with a warm surface and upper-level flow, the environment will be favorable for ozone development. Because of this threat, we have issued an Air Quality Advisory for Saturday, which includes Muskegon and areas south to the state line.

The heat and humidity continue to build Sunday, and more in the way of sunshine is expected across the state. Ozone-conducive conditions will increase in the northern lakeshore areas Sunday; therefore, we have expanded the advisory for ozone north, along the west Michigan lakeshore. Across the rest of the state, ample sunshine is expected, along with hot temperatures; however, we anticipate the strong winds and high humidity levels to keep ozone from reaching higher than Moderate. Without an airmass change expected in the short-term, the threat of increased ozone will continue. This forecast will be updated Sunday to determine the need to continue or expand the current air quality advisory.

Ozone will be the dominant pollutant through early next week. We anticipate increases in PM2.5 concentrations during this period, but we do not expect daily averages to exceed the low to middle Moderate range.

 EXTENDED FORECAST:

 Extended models show the heat and humidity lingering into next week. We will be updating the forecast throughout the weekend do determine if air quality advisories are needed later in the forecast period.

 Next Forecast update: Sunday, June 22, 2025

06/20/2025 Forecast Update

FORECAST SUMMARY: Friday, June 20, 2025 - Saturday, June 21, 2025

 Ozone: 8-hour ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI), with USG (Orange, AQI) possible along the west Michigan lakeshore.

 PM-2.5: 24-hour daily average Fine Particulate concentrations will range between Good and Moderate.

 The Michigan Department of Environment, Great Lakes, and Energy (EGLE) has declared an Air Quality Advisory for June 21, 2025, for elevated levels of ozone in southwestern counties of Michigan. Pollutants within those areas are expected to be in the Unhealthy for Sensitive Groups (USG, Orange AQI) range.

The Air Quality Advisory is in effect for the following Michigan counties:

Allegan, Berrien, Kent, Muskegon, Ottawa, and Van Buren

 FORECAST DISCUSSION:

Hot temperatures and humidity are the main forecast points for this weekend. Temperatures in the 90s, along with increased humidity, will make it “feel” like 100+ degrees in parts of the state. Those with outside plans should exercise caution. Forecast maps show a storm complex moving through the central and eastern areas early Saturday. There is a lot of uncertainty with the placement and timing of this complex, but any associated precipitation looks to end as Saturday progresses. This system looks to miss the west/southwest portion of the state. With ample sunshine expected in that portion of the state, along with a warm surface and upper-level flow, the environment will be favorable for ozone development. Because of this threat, we have issued an Air Quality Advisory for Saturday, which includes Muskegon and areas south to the state line.

The heat and humidity continue to build Sunday, and more in the way of sunshine is expected across the state. With there being a threat for ozone development to continue or expand, this forecast will be updated tomorrow.

Ozone will be the dominant pollutant through early next week. During this period, PM2.5 concentrations are expected to range from upper Good to middle Moderate.

 EXTENDED FORECAST:

 Extended models show the heat and humidity lingering into next week. We will be updating the forecast throughout the weekend do determine if air quality advisories are needed later in the forecast period.

 Next Forecast update: Saturday, June 21, 2025

06/16/2025 Forecast Update

FORECAST SUMMARY: Monday, June 16, 2025, through Friday, June 20, 2025

Air Quality Advisory for Tuesday, June 17, 2025

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) is issuing an Air Quality Advisory for elevated levels of ozone for several counties along the Western Michigan lake shore.  Pollutants within those areas could reach the Unhealthy for Sensitive Groups (Orange AQI) range. 

The Tuesday Air Quality Advisory includes the following West Michigan counties:

Allegan, Berrien, Cass, Kent, Muskegon, Ottawa, and Van Buren

OZONE: 8-hour average Ozone concentrations are expected to range between Good (AQI Green) and Moderate (AQI Yellow) for most of the state with several West Michigan lake shore counties expected to see USG (AQI Orange) during Tuesday.

PM-2.5:  24-hour average Fine Particulate concentrations are expected to range from Good (AQI Green) to Moderate (AQI Yellow). 

FORECAST DISCUSSION

Although smoke advisories are no longer an issue for the meantime, we are getting into the peak season for ozone development.  This will be the case for Tuesday, as all signs point towards the likely development of elevated ozone along several western lake shore counties.  Elements such as wind direction, temperature, dew points, upper air conditions all point towards the likelihood that could see ozone concentration in the USG range along those counties.  Cloud cover is uncertain during the peak heating hours of the day, but enough sun will likely be present to trigger the photochemical reactions necessary to generate ozone.  As a result, we are issuing an advisory along the West Michigan lake shore counties to address that threat.

 A surface front does eventually drop down over the area by Tuesday night.  By Wednesday morning, we are likely to see a warm front to our southwest push northward through the southern counties setting up the area for potential severe weather by Wednesday evening.

 A brief reprieve from the heat and humidity will take place on Thursday in the wake of the following cold front. High pressure ridging begins to build north and eastward into the region during Friday and by the weekend dew points will be back into the lower 70s and daytime highs will be back into the upper 80’s and lower 90’s with the heat index running even higher.

  EXTENDED FORECAST:

 Air Quality could be an issue with increasing heat and humidity during the upcoming weekend.

06/10/2025 Forecast Update

FORECAST SUMMARY: Tuesday June 10, 2025, through Wednesday June 11, 2025

Ozone:

Ozone concentrations are expected to be in the Moderate to Unhealthy for Sensitive Groups range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good to Moderate range.

Air Quality Advisory for Wednesday June 11, 2025

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) has declared an Air Quality Advisory for June 11, 2025, for elevated levels of ozone in southwestern counties of Michigan. Pollutants within those areas are expected to be in the Unhealthy for Sensitive Groups (USG, Orange AQI) range.

The Air Quality Advisory is in effect for the following Michigan counties:

 Allegan, Berrien, Kent, Muskegon, Ottawa, and Van Buren

FORECAST DISCUSSION:

Dry and clear conditions will continue throughout today, Tuesday, and will carry into tomorrow, Wednesday. Surface temperatures today will hang around the low-to-mid 70s before increasing into the mid-to-upper 80s on Wednesday. Winds shifting to a more southwestern direction will help increase the temperatures into the 80s. The wind direction will also increase Ozone development in the southwest Michigan area, especially along the Lake Michigan shoreline. The ingredients for a conducive Ozone environment will be in place tomorrow, hence the Air Quality Advisory for Ozone. Residual smoke within the atmosphere may also help to produce Ozone in the impacted areas. Wildfire smoke for northern areas, into the upper peninsula, may return in high-Moderate concentrations later today and into tomorrow. Model guidance has not treated the outlook today accurately, but multiple hours of USG-level PM-2.5 is not expected at this time.

After Wednesday, a Low-pressure system looks to move over Michigan with a stationary front staying just to our south come Friday. This set up will keep the atmosphere moist enough to hold clouds but not cause a total washout in terms of rain. With the Air Quality Advisory in place, this forecast will be updated Wednesday morning to look at the days ahead.

EXTENDED FORECAST:

Partly cloudy conditions look to persist through the rest of the week, but temperatures hang around the 70s to 80s. Air quality will hang around the Good to Moderate range after Wednesday.

Next Forecast update: Wednesday June 11, 2025

06/09/2025 Forecast Update

FORECAST SUMMARY: Monday June 9th, 2025, through Tuesday June 10th, 2025

Ozone:

Ozone concentrations are expected to be in the Good to Moderate range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Moderate range.

FORECAST DISCUSSION:

As we get into the second week of June, we are continuing to look at wildfire smoke impacts not only across Michigan, but across the Great Lakes as well. This past weekend saw lingering smoke across southern Michigan with metro Detroit seeing most of the smoke Saturday and into Sunday evening. A cold front came through late Sunday night and helped to wash out the USG level PM-2.5 and smoke concentrations. This Monday morning presents us with statewide Moderate concentrations with another frontal boundary expected to cross over us later today. Looking to our west over Minnesota and Wisconsin, concentrations are a mixed bag of Good to Moderate, but great improvements overall, nonetheless, compared to this past weekend and last week. Ideally, with the passage of the forthcoming front, we will drop down into the Good range for PM-2.5. However, some models are showing additional smoke dropping down into the upper peninsula tomorrow, Tuesday, while other guidance are not picking up on the smoke at all. With the experience we have gained with this last episode with some models performing well, while others did not, I will be looking at and updating this forecast Tuesday morning. Also, Ozone may become an issue come Wednesday with clearing skies and warming temperatures. Residual smoke near the surface may help to enhance Ozone development in the more populated areas.

EXTENDED FORECAST:

Consistently warm temperatures look to hang around and stay as we get into the second week of June. Additional rain showers linger around this week, but nothing to cause a washout. Air quality will be monitored each day this week with hopes of additional rain and fronts cleaning out our current airmass.

Next Forecast update: Tuesday June 10th 2025

06/05/2025 Forecast Update

FORECAST SUMMARY: Thursday, June 5, 2025, through Friday, June 6, 2025

Air Quality Advisory for Thursday – Friday Noon, June 5-6, 2025

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) is issuing an Air Quality Advisory for elevated levels of fine particulate (PM2.5) for all counties in the Lower Peninsula.  Pollutants within those areas could reach the Unhealthy for Sensitive Groups (Orange AQI) range. 

The Thursday-Friday Noon Air Quality Advisory includes the following counties:

Lower Peninsula

All Lower Peninsula counties…

OZONE: 8-hour average Ozone concentrations are expected to range between Good (AQI Green) and Moderate (AQI Yellow).

PM-2.5:  24-hour average Fine Particulate concentrations are expected to range from Moderate (AQI Yellow) in the Upper Peninsula to mostly USG (AQI Orange) and occasional Unhealthy (AQI Red) in the Lower Peninsula. 

FORECAST DISCUSSION

Smoke from Canadian wildfires continues to threaten Michigan.  The Wednesday Air Quality models indicated USG level concentrations would be isolated to the Northern Lower Peninsula, but a review of the Thursday morning monitors showed the thickest of the smoke had advanced further south, than anticipated, and will continue southward.  As such, the AQD has modified the Thursday forecast to place the entirety of the Lower Peninsula in a USG Advisory status from Thursday until noon, Friday.  Some monitors are currently showing hourly values in the Unhealthy range, but we do not expect concentrations that high that to persist.

This episode should finally conclude by the end of Friday.  The Upper Peninsula is already beginning to clean out and Moderate conditions are migrating southward.  There is still a considerable amount of smoke in Canada and the models are indicating a late weekend frontal system could draw down more smoke, next week.  However, it is too early to make any firm forecasts.

Although we expect Friday to be the last day for Advisories, we will update this forecast, Friday morning, to confirm the end of this smoke episode and the potential for any late weekend smoke.

EXTENDED FORECAST:

Air Quality is expected to finally show improvement by the weekend but could deteriorate by the end of the weekend.

Next forecast update: Friday, June 6, 2025

06/03/2025 Forecast Update

FORECAST SUMMARY: Tuesday, June 3, 2025, through Wednesday, June 4, 2025 

Air Quality ALERT for Tuesday and Wednesday, June 3-4, 2025

The Michigan Department of Environment, Great Lakes, and Energy (EGLE) is upgrading to Air Quality Alert for elevated levels of fine particulate (PM2.5) in the Upper Peninsula of Michigan and several counties in the Northwest Lower Peninsula.  Pollutants within those areas could reach the Unhealthy (Red AQI) range or higher. 

The Air Quality Alert includes the following counties:

Upper Peninsula:

Alger, Baraga, Chippewa, Delta, Dickinson, Gogebic, Houghton, Iron, Keweenaw, Luce, Mackinac, Marquette, Menominee, Ontonagon, Schoolcraft

Lower Peninsula

Antrim, Benzie, Charlevoix, Cheboygan, Emmet, Grand Traverse, Kalkaska, Leelanau, Manistee

OZONE: 8-hour average Ozone concentrations are expected to range between Good (AQI Green) and Moderate (AQI Yellow).

PM-2.5:  24-hour average Fine Particulate concentrations are expected to be Moderate (AQI Yellow) in most of the Lower Peninsula, and likely USG (AQI Orange) to Unhealthy (AQI Red) in the Upper Peninsula and several counties in Northwest Lower Peninsula. 

FORECAST DISCUSSION

Similar to yesterday’s forecast, smoke from Canadian wildfires continues to threaten the upper Midwest.  For the most part, the worst of the smoke has remained elevated over Michigan skies.  However, monitors in the western U.P. are showing a large increase surface concentrations, during Tuesday morning, as smoke mixes down, sending PM-2.5 concentrations into the Unhealthy and higher range.  As such we are upgrading Tuesday’s forecast to Alert status and will maintain that level through Wednesday.  The models are also showing surface smoke invading the northwest counties of the Lower Peninsula during Wednesday, so we will increase the Alert area to cover those counties for Wednesday.  We will reassess the situation for Thursday with the Wednesday forecast.

Warmer weather is still on tap for Tuesday temperatures into the 80’s for the rest of the Lower Peninsula.  Skies should be remain mostly clear, during Tuesday, but show shades of gray to brown rather than blue due to the elevated smoke.  Although we are experiencing ozone levels in the High Moderate range, during Monday, along the western lake shore, we are not expecting ozone to reach USG due to the elevated smoke dimming much of the solar energy along with clouds moving in during Wednesday. 

The cold front should pass during Wednesday afternoon with decent rainfall potential.  It remains to be seen how the smoke will behave during the rain and following the front.  As such, we will update this forecast, Wednesday morning, and as necessary during this smoke episode.

EXTENDED FORECAST:

Air Quality is expected to vary during the week dependent smoke conditions.

Next forecast update: Wednesday, June 4, 2025

06/01/2025 Forecast Update

FORECAST SUMMARY: Sunday, June 1, 2025 - Monday, June 2, 2025

 Air Quality Advisory for Monday, June 2, 2025

 The Michigan Department of Environment, Great Lakes, and Energy (EGLE) has issued an Air Quality Advisory for elevated levels of fine particulate (PM2.5) in the Upper Peninsula of Michigan. Pollutants within those areas are expected to be in the Unhealthy for Sensitive Groups (USG, Orange AQI) range.

 The Air Quality Advisory includes the following counties:

 Alger, Baraga, Chippewa, Delta, Dickinson, Gogebic, Houghton, Iron, Keweenaw, Luce, Mackinac, Marquette, Menominee, Ontonagon, Schoolcraft

 Ozone: 8-hour ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI).

 PM-2.5: 24-hour daily average Fine Particulate concentrations will range between Good and Moderate, but Unhealthy for Sensitive Groups (USG, Orange AQI) across the Upper Peninsula on Monday.

 FORECAST DISCUSSION:

 Smoke from Canadian wildfires continues sinking south into the Dakotas and Minnesota on Sunday. Overnight Sunday, a warm front tracks east into the Upper Peninsula of Michigan. Southwesterly winds will develop, bringing increased fine particulate to the northern portions of Michigan on Monday. As a result, we anticipate fine particulate levels rising into the Unhealthy for Sensitive Groups (USG) range across the Upper Peninsula. There is a possibility that hourly levels could reach the Unhealthy (red AQI) range for a short period of time.

 Across the rest of the state, southwest winds develop as a ridge moves in from the west. We expect smoke to persist mostly at upper levels on Monday. While concentrations of fine particulate may increase, readings higher than mid- to upper Moderate are not expected. For ozone, warmer temperatures moving into the area may cause increases in concentrations. There is a small chance for a monitor to reach the low-end USG range for ozone and/or fine particulate on Monday, but the threat is not enough to warrant an advisory across the Lower Peninsula. By Tuesday, we will be in the second day of warmer temperatures, and southwest winds will continue. There is a possibility that smoke may start filtering down towards the surface by then, so a threat exists for elevated fine particulate and/or ozone. The forecast and smoke maps will be evaluated Monday morning to determine if additional air quality advisories are needed.

 EXTENDED FORECAST:

 Extended models show a boundary moving into the region later Tuesday, lingering through the rest of the week. This boundary will trigger storm development. Air quality levels during this period will continue to be evaluated.

 Next Forecast update: Monday, June 2, 2025

05/31/2025 Forecast Update

FORECAST SUMMARY: Saturday, May 31, 2025 - Sunday, June 1, 2025

 Ozone: 8-hour ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI).

 PM-2.5: 24-hour daily average Fine Particulate concentrations will also range between Good and Moderate.

 FORECAST DISCUSSION:

 As expected, we saw increases in fine particulate from north to south Friday through early Saturday as a cold front pushed a smoke plume through the state. Several locations experienced hourly increases of fine particulate into the Unhealthy for Sensitive Groups (USG, Orange AQI) range for a few hours, but by mid-morning Saturday, levels had improved, with all areas in the Good to low Moderate range.

 High pressure well north of the state will control conditions Saturday and Sunday. Cool northerly winds in place on Saturday keep temperatures mainly in the 60s, and readings only improve a few degrees on Sunday. During the next two days, upper-level winds are from a northerly direction. Smoke models show smoke lingering over the state this weekend, but at upper levels. With not much surface influence, fine particulate and ozone levels are not expected to reach higher than Moderate the next two days.

 To our west, thick smoke plumes are sinking into the Dakotas and Minnesota this weekend. By Monday, a ridge will build into our region, and as this happens, smoke will be transported back into the state on a southwest flow. The smoke is expected to move into the western portion of the Upper Peninsula early Monday, then across the rest of the state later Monday into Tuesday. This is something we are watching, and it is possible that an Air Quality Advisory or Alert may be needed for Monday. This forecast will be updated Sunday morning to detail the most recent models and our decision on whether a pollution day is warranted.

 EXTENDED FORECAST:

 Extended models show a boundary approaching northern areas on Tuesday, bringing precipitation back into the forecast. Warm temperatures and southerly winds ahead of this boundary will keep the threat for increased pollution in place.

 Next Forecast update: Sunday, June 1, 2025

05/30/2025 Forecast Update

FORECAST SUMMARY: Friday, May 30, 2025 - Saturday, May 31, 2025

 Ozone: 8-hour ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI).

 PM-2.5: 24-hour daily average Fine Particulate concentrations will average between Moderate and USG (Orange AQI).

 Air Quality Advisory for Michigan starting Friday (May 30th) until 6 am Saturday (May 31st)

 The Michigan Department of Environment, Great Lakes, and Energy (EGLE) has issued an Air Quality Advisory for elevated levels of fine particulate (PM2.5) across the state of Michigan. Pollutants across the state expected to be in the Unhealthy for Sensitive Groups (USG, Orange AQI) range Friday into Saturday morning.

 The Air Quality Advisory includes all Michigan counties.

FORECAST DISCUSSION:

 The Air Quality Advisory issued yesterday for the western Upper Peninsula has been expanded to cover all of Michigan. Forecast models Friday morning are consistent with showing a cold front moving down from Ontario Friday, bringing in smoke plumes from wildfires in the provinces of Manitoba and Saskatchewan. The smoke plumes, along with the associated increase in PM2.5 levels, will move from north to south across the state from Friday morning until Saturday morning. Increased vertical mixing associated with the boundary will likely bring smoke to the surface. As a result, we anticipate PM2.5 levels rising into the Unhealthy for Sensitive Groups (USG) range across the state. There is a possibility that hourly levels could reach the Unhealthy (Red AQI) range for a short period of time. While not all locations will experience USG levels, it would be hard to pinpoint exact locations, and the threat seems to be widespread enough to warrant the statewide advisory.

 Increased levels of fine particulate were being seen early Friday in the western portion of the Upper Peninsula, and increases will spread south as the day progresses. The frontal boundary clears the state Saturday morning, and winds switching to a north/northeast direction will push the smoke south and west of the state. Some lingering smoke could allow for a continuation of Moderate fine particulate on Saturday, especially in southern areas.

 For ozone, clouds associated with the Friday front and northerly winds on Saturday should hamper any significant development. Readings of ozone are not expected to reach higher than Moderate.

EXTENDED FORECAST:

 There is a possibility that smoke returns to the region late in the weekend. Since there is a lot yet to be determined for early next week, this forecast will be updated Saturday morning.

 Next Forecast update: Saturday, May 31, 2025

05/27/2025 Forecast Update

FORECAST SUMMARY: Tuesday May 27th, 2025, through Friday May 30th, 2025

Ozone:

Ozone concentrations are expected to be in the Good range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good to low-Moderate range.

FORECAST DISCUSSION:

The slow climb back to seasonally normal temperatures continues this week as we return to the 70s. An upper-level pattern in the atmosphere is providing temperatures near our normal highs for this time of year with a slight dip below normal throughout the week. The dip will be tomorrow, Wednesday, as a Low-pressure moves in from the south, cooling down temperatures and producing rain showers for most of the state. It is not expected to be a complete washout, but lingering rain showers should be expected. This pressure system moves out of the area come Thursday afternoon and a rather nice weather pattern sets up for the weekend ahead come Friday.

For air quality, although temperatures, on average, this week are increasing, they are still too cool for any real Ozone development. Couple that with rain showers and mostly cloudy skies for a good majority of the week, Ozone will predominantly be in the Good range. PM-2.5 concentrations will follow the same pattern with Good AQI throughout the week due to lingering rain showers and northwesterly flow later in the week providing cleaner air. During the morning commute hours when winds are light, there may be a few hours of low-Moderate concentrations in the metro areas, but those concentrations will dissipate throughout the day. I will note that there are currently active wildfires in northwestern Ontario and eastern Manitoba. Smoke from these fires may make its way towards the western upper peninsula later this week and into the weekend, but nothing is certain as of now. Our eyes will be watching the fire activity throughout this week.

EXTENDED FORECAST:

As mentioned above, warmer and sunnier weather conditions are on the horizon with the help of a favorable upper-level pattern setting up for the weekend. Air quality concentrations are expected to remain in the Good range.

Next Forecast update: Friday May 30th, 2025

05/23/2025 Forecast Update

FORECAST SUMMARY: Friday May 23rd, 2025, through Tuesday May 27th, 2025

Ozone:

Ozone concentrations are expected to be in the Good range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good range.

FORECAST DISCUSSION:

After a week of rather subpar weather, conditions are looking onward and upward, especially in the temperature regime. The Low-pressure that was lingering around the Great Lakes this past week has moved off to the east which opened the door for a rather dominant High-pressure system to take its place. This system will stick around for the entirety of the holiday weekend and early next week. The center of the pressure system will dance between the western upper peninsula and northern Wisconsin, so winds from the north-northwest will be commonplace for the weekend ahead. Along with this, mostly sunny conditions will be present as well as light winds after today, Friday. Breezy conditions should be expected today as the two pressure systems become closer in proximity, producing the winds, before the Low-pressure completely moves out of the area. With the aid of the sun, surface temperatures slowly increase throughout the weekend with the 60s returning tomorrow, Saturday, and the mid-to-upper 60s returning to the Great Lakes come Sunday. The warmest day of the holiday weekend will be Monday with upper 60s throughout the state and the slow climb back into the 70s continues into next week.

For air quality, persistently Good air quality will stick around for the weekend due to cooler temperatures not initiating too much Ozone across the state. For PM-2.5, northerly winds will help to keep the air clean, but with lighter winds and stagnation at times, low-Moderate concentrations can be expected in the metro Detroit and Grand Rapids areas. Those low-Moderate concentrations will be on an hourly basis however, with the daily PM-2.5 average expected to be in the Good range.

EXTENDED FORECAST:

The slow climb back to the 70s and seasonal norms continues next week with a slight chance of rain. Air quality is expected to be in the Good to low-Moderate range.

Next Forecast update: Tuesday May 27th, 2025

05/16/2025 Forecast Update

FORECAST SUMMARY: Friday, May 16, 2025, through Monday, May 19, 2025

OZONE: 8-hour average Ozone concentrations are expected to range between Good (AQI Green) and Low Moderate (AQI Yellow) during Friday, then mostly Good (AQI Green) for the remainder of the weekend.

PM-2.5: 24-hour average Fine Particulate concentrations are also expected to range between Good (AQI Green) to Low Moderate (AQI Yellow) through the forecast period.

FORECAST DISCUSSION

After the hard-hitting storms rolled through Thursday evening, Friday will be calm with sunny skies and breezy, warm temperatures. It will end, Friday evening, when a second batch of storms arrives associated with a cold front currently tracking across the Michigan Upper Peninsula. I do not expect that these storms will be as robust as the Thursday evening storms, but there could be some decent thunderstorms associated with this passage. Friday’s Air Quality should be a mix of Good and Low Moderate.

Cooler weather, with a chance of showers, is on tap for Saturday with temperatures struggling to reach 60 degrees under breezy conditions. Air Quality should be a mix of Good and Low Moderate but mostly Good.

A Canadian high pressure system builds in, during Sunday, with fair weather for the remainder of the weekend and into early next week. Cooler weather remains with daily highs in the 60’s and potentially scattered frost with lows in the 30’s across the northern zones of the forecast region. Air Quality should be mostly Good.

EXTENDED FORECAST:

Air Quality is expected to continue being mostly Good going into the upcoming work week.

Next forecast update: Monday, May 19, 2025

05/12/2025 Forecast Update

FORECAST SUMMARY: Monday, May 12, 2025, through Friday, May 16, 2025

OZONE: 8-hour average Ozone concentrations are expected to range between Good (AQI Green) to Low Moderate (AQI Yellow).

PM-2.5:  24-hour average Fine Particulate concentrations are also expected to range between Good (AQI Green) to Low Moderate (AQI Yellow) through the forecast period.

 FORECAST DISCUSSION

Monday will continue the weekend act with clear skies, low humidity, and temperatures reaching the 80’s.  Ozone will likely reach the Moderate range in the southern half of the state while fine particulates will range between Good and Moderate, statewide.

Clouds and moisture move into the state, Monday night, leading to an increased chance of shower activity for Tuesday and Wednesday.  Under cloudy skies, ozone concentrations will be Good while fine particulates will continue to range between Good and Moderate.

Thursday should return to partly sunny skies and warmer, more humid conditions.  That will lead to the possibility of strong to severe storms during Thursday night as a cold front moves through.  Air Quality should range between Good and Moderate before drier air returns during Friday with mostly Good Air Quality.

 EXTENDED FORECAST:

 Air Quality is expected to continue being mostly Good going into the upcoming weekend.

05/05/2025 Forecast Update

FORECAST SUMMARY: Monday, May 5, 2025 - Friday, May 9, 2025

Ozone: 8-hour ozone concentrations are expected to be in the Good (Green AQI) range through the period.

PM-2.5: 24-hour daily average Fine Particulate concentrations will average mostly Good (Green AQI).

FORECAST DISCUSSION:

 Michigan is placed between two weather systems early this week: high pressure north of the Great Lakes region and a low-pressure area spinning in the Ohio Valley. High pressure dominates conditions across much of the Upper Peninsula on Monday and Tuesday. Up north, nice springtime weather conditions can be expected with sunshine and temperatures in the upper 60s to around 70 degrees. However, the Lower Peninsula will be influenced by the low, with cooler temperatures anticipated along with chances for showers, especially later Monday into Tuesday. On Wednesday, a weak cold front sinks north to south across the state. Not much in the way of precipitation is expected, but temperatures will cool, especially across the north. High pressure then sinks in from Canada to end the workweek. Sunshine is expected along with temperatures increasing towards the 70-degree mark.

As for air quality, this forecast period begins with Good levels. Forecast maps show a northerly surface and upper-level flow remaining in place throughout this forecast period, and this should translate to generally Good air quality conditions across the region.

EXTENDED FORECAST:

 The extended weather models show high pressure dominating the start of the weekend, but a weak boundary could bring scattered precipitation back into the forecast late Saturday into Sunday. During the period, high temperatures should range from the upper 60s to the low 70s. Air quality conditions could see an uptick into the moderate range late in the weekend.

 Next Forecast update: Friday, May 9, 2025

05/02/2025 Forecast Update

FORECAST SUMMARY: Friday May 2nd, 2025, through Monday May 5th, 2025

Ozone:

Ozone concentrations are expected to be in the Good range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good to low-Moderate range.

FORECAST DISCUSSION:

We wrap up this work week cooler than when it started as a cold front and associated rain showers made their way through the state yesterday, Thursday. Residual clouds and a slight chance of a pop-up shower can be expected today, Friday, but overall, the majority of Michiganders should remain dry. Sunshine will return to kick off the weekend early Saturday and will continue to peek through the clouds throughout the day. This is due to a High-pressure system drifting in from the west later this evening and into Saturday evening. Surface temperatures will hang around the 50s for most of the state due to predominantly northerly winds from the High-pressure system. As we get into Sunday, a Low-pressure system along with a frontal boundary tries to make its way through the state from the south, but High-pressure lingering to the west should keep it at bay for mid to northern parts of the state. Rain should be expected for southern parts of the state on Sunday as the Low-pressure slowly lifts northwards Sunday morning. Similar to Sunday, Monday will have lingering showers as well, as the pressure system hangs around the Great Lakes until late Monday.

For air quality, the drop in temperatures and cloudy skies will keep Ozone concentrations in the Good range for the weekend ahead. Shifting winds will keep the PM-2.5 concentrations in the Good range for much of the weekend. However, today, Friday, may see low-Moderate concentrations in the more populated areas across the state.

EXTENDED FORECAST:

Temperatures increase as we get into next week. Air quality will remain in the Good to low-Moderate range.

Next Forecast update: Monday May 5th, 2025

04/28/2025 Forecast Update

FORECAST SUMMARY: Monday April 28th, 2025, through Friday May 2nd, 2025

Ozone:

Ozone concentrations are expected to be in the Good to low-Moderate range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good to low-Moderate range.

FORECAST DISCUSSION:

With the last few days of April upon us, we round off this month with surface temperatures above average in the 70s and quite a bit of sunshine. These temperatures are aided by southerly flow and a rather warm airmass which will be sitting over us today and most of tomorrow, Tuesday. Today will predominantly be dry for most Michiganders with the western upper peninsula seeing rain and potential storms later today. Rain showers and additional storms will cross over the state on Tuesday before exiting the region and opening the skies on Wednesday with the help of a High-pressure system sitting to our north. Although short-lived, the High-pressure will move off to the east and will leave the door open for a Low-pressure and an accompanying frontal boundary which will bring in a few rain showers. The passing of the frontal boundary will drop temperatures down to near-normal temperatures come late Thursday and into Friday. Friday looks to have lingering showers throughout the day with northeasterly winds providing near-normal temperatures for early May.

For air quality this week, temperatures well into the 70s on Monday and Tuesday will allow for Ozone to likely develop into the Moderate range, especially on Monday with ample sunlight. Late day clearing on Tuesday may allow for low-Moderate concentrations of Ozone, but nothing more than that. Throughout the week, multiple rounds of rain showers across the state will help keep Ozone at bay with cloudy conditions helping even more so. Unfavorable winds, northerly, for Ozone development will also help keep concentrations at bay this week. For PM-2.5, low-to-mid Moderate concentrations can be expected early this week due to southerly flow. Thankfully, however, breezy conditions will be in place to keep the air moving and dispersing, so stagnation should not be an issue to let PM-2.5 concentrations pool in more urban areas. Rain showers throughout the week will help keep PM-2.5 concentrations at bay as well.

EXTENDED FORECAST:

Seasonal normal temperatures are on the horizon this week with clear skies to kick off the month of May. Air quality will remain in the Good to low-Moderate range.

Next Forecast update: Friday May 2nd, 2025