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

04/25/2025 Forecast Update

FORECAST SUMMARY: Friday, April 25, 2025, through Monday, April 28, 2025

OZONE: 8-hour average Ozone concentrations are expected to be Good (AQI Green).

PM-2.5:  24-hour average Fine Particulate concentrations are expected to range between Good (AQI Green) to scattered Low Moderate (AQI Yellow) during Friday, then mostly Good (AQI Green) for the remainder of the weekend.

FORECAST DISCUSSION

A front stalled across lower Michigan will likely provide shower activity during Friday afternoon and early evening.  I am not expecting any severe weather associated with this system although a random pop-up thunderhead is not out of the question.  Air Quality will be mostly Good with occasional Low Moderate mostly confined to Southeast Michigan.

High pressure will push out the frontal activity, during early Saturday morning, bringing cooler, dryer air into the region for the weekend.  Northerly wind flow will keep temperatures on the cooler side with Saturday night lows in the 30’s.  Weekend highs will be in the 50’s to low 60’s, which is normal for this time of year.  Decreasing clouds on Saturday will lead to mostly sunny skies for Sunday and Monday.  Air Quality is expected to be mostly Good through the weekend.

EXTENDED FORECAST:

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

Next forecast update:  Monday, April 28, 2025

04/21/2025 Forecast Update

FORECAST SUMMARY: Monday, April 21, 2025, through Friday, April 25, 2025

OZONE: 8-hour average Ozone concentrations are expected to be Good (AQI Green).

PM-2.5:  24-hour average Fine Particulate concentrations are expected to be mostly Good (AQI Green) with scattered Low Moderate (AQI Yellow).

FORECAST DISCUSSION

Low pressure, with associated cold front, enters the Lake Michigan region late Monday morning and will continue to track off to the northeast.  Isolated showers and storms have developed, earlier this morning, with generally widespread precipitation.  Drier air should limit precipitation opportunities, Monday afternoon, and winds will remain gusty throughout the day.

High pressure follows Monday’s frontal passage making Tuesday likely the nicest day of the week to be outdoors.  Sunny skies are expected with afternoon temperatures reaching the mid-60’s.

A weak warm front lifts into the region Tuesday night with a chance for shower development overnight and possibly into early Wednesday.  The southern counties could see temperatures push toward 70 degrees during Wednesday with the best chance of the week to see scattered fine particulate matter in the Moderate range, mostly in the urban areas.

Precipitation chances increase Thursday night into Friday as a low-pressure system moves into the Midwest bringing the potential for both showers and thunderstorms.  Conditions then dry out for the weekend as high pressure moves back into the Upper Great Lakes region.

 All in all, the work week looks reasonably quiet, with several chances for scattered precipitation and I do not see any serious concern with Air Quality.  PM-2.5 will be a mix of mostly Good to scattered Low Moderate.  Ozone concentrations are expected to be Good throughout the week.

 EXTENDED FORECAST:

Air Quality is expected to continue being mostly Good to scattered Low Moderate going into the upcoming weekend.
Next Forecast update: Friday, April 25, 2025

04/18/2025 Forecast Update

FORECAST SUMMARY: Friday, April 18, 2025, through Monday, April 21, 2025

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

 PM-2.5: 24-hour daily average Fine Particulate concentrations will range between Good (Green AQI) to low Moderate (Yellow AQI).

 FORECAST DISCUSSION:

 A storm system moving through Friday will bring periods of showers and storms as it tracks through. Some of the storms could be strong, so it’s something you may want to keep an eye on. High pressure then slides in on Saturday; however, the next system moves into the region on Sunday, bringing showers back into the forecast on Easter. Southwest winds across lower Michigan on Friday allow temperatures to reach the mid-60s to mid-70s, but readings will fall into the 50s to 60s on Saturday as northwest winds develop. Further north, temperatures are expected to range in the 50s on Friday and then into the 40-to-50-degree range during the weekend.

 As for air quality, the period begins with a mix of Good to low Moderate fine particulate levels and Good ozone readings. These concentrations will continue Friday, and an improvement to all Good is expected Saturday as northwest winds kick in. Mostly Good air quality levels are expected to linger through the coming weekend, with only a chance for low-Moderate fine particulate in the south early next week.

 EXTENDED FORECAST:

 The extended weather models show precipitation continuing Monday, but dry weather returns on Tuesday. Temperatures will be cooler early in the week, but milder conditions are forecast by mid-week. Pollution levels early next week will average Good for ozone and a mix of Good to low-Moderate for fine particulate.
Next Forecast update: Monday, April 21, 2025

04/11/2025 Forecast Update

FORECAST SUMMARY: Friday April 11th, 2025, through Monday April 14th, 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:

High-pressure and clear skies round off the work week and kickoff the weekend for us Michiganders. Many of us will approach the 50-degree mark today, Friday, while others stay in the low-to-mid 40s. As we get into Saturday, the High-pressure system moves right over top of us providing ample sunlight and minimal clouds with surface temperatures well into the 50s throughout the state. These warming temperatures will be provided by southwesterly winds as they wrap around the High-pressure system before it moves off the to the east come Sunday. An encroaching Low-pressure system somewhat spoils the weekend fun with potential spotty rain expected on Sunday, but temperatures remain in the 50s, however. The Low-pressure system continues to move eastward throughout Sunday and into Monday as even warmer temperatures are expected Monday to kick off the next week.

While winds stay more stagnant today, PM-2.5 concentrations are expected to remain in the Good to low-Moderate range. Shifting winds tomorrow will help decrease and keep these concentrations at bay for the time being. As winds shift to a more southerly direction, particulate from the south may increase concentrations to the low-Moderate range for much of Sunday and into Monday. For Ozone, like a broken record, it is still not warm enough for any real Ozone development this weekend. As temperatures warm into the 60s on Monday, however, we may see a few monitors eclipse the Moderate range for an hour or so, especially in more populated areas.

EXTENDED FORECAST:

The aforementioned Low-pressure system will bring a cold front along with it which will cool down temperatures for Tuesday, but we quickly rebound come midweek. Air quality should reman in the Good range.

Next Forecast update: Monday April 14th, 2025

04/07/2025 Forecast Update

FORECAST SUMMARY: Monday April 7th, 2025, through Friday April 11th, 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 first full week of April is upon us, and it looks like Michiganders will have to wait a few more days to see warm April weather. A cold front drops down from our north throughout the day today bringing north-northwesterly winds and snowfall for the entire state. The upper peninsula and northern lower peninsula will see most of the accumulation with mid-Michigan and southward only seeing flurries with trace amounts of accumulating snow. The cold front leaves clear conditions in its wake for Tuesday and a good amount of Wednesday before another Low-pressure system approaches the Great Lakes late Wednesday and kicking up rain showers for southern portions of the state. Once we get through the first half of the week, there is a rather steady incline in temperatures which will carry us into the weekend ahead. For the latter half of the week, we will see High-pressure hanging around with winds coming from the south—providing temperatures returning to the 50s and 60s.

Northerly winds for the beginning half of the week will help keep air quality in the Good range as there appears to be little to zero smoke or dust in the area to impact PM-2.5 concentrations and it is still too cold for Ozone to develop. Once we get into the latter part of the week, warmer temperatures may bring hourly Moderate concentrations for PM-2.5 These concentrations will mainly be contained to the morning rush hour timeframe with dissipating concentrations throughout the day. It should be noted that there are current fires burning in southern plain states, so there will be continued smoke entering the atmosphere. As of now, this smoke does not look to impact Michigan, but smoke concentrations will be monitored. Ozone may see an increase towards Moderate, but it will still be too cold for any real Ozone development.

EXTENDED FORECAST:

As mentioned above, warm and clear conditions look to be on deck for the weekend ahead. Air quality is expected to remain in the Good range.

Next Forecast update: Friday April 11th, 2025

04/04/2025 Forecast Update

FORECAST SUMMARY: Friday, April 4, 2025, through Monday, April 7, 2025

OZONE: 8-hour average Ozone concentrations are expected to be Good (AQI Green).

PM-2.5:  24-hour average Fine Particulate concentrations are expected to be a mixture of Good (AQI Green) to scattered Low Moderate (AQI Yellow).

FORECAST DISCUSSION

High pressure will remain centered over the Great Lakes, during Friday, and will maintain dry conditions and seasonal temperatures through late afternoon.  The center of the high will drift across the northern Great Lakes, today, maintaining an easterly component and light winds.

Another low-pressure system will pass through the already battered mid-south states during Saturday and Sunday.  While most of our forecast area should receive some additional rainfall, the best chance of significant rain will be south of our border.  The border counties up to I-94, however, could see up to 1.25 inches of additional rain.  The timing of that event could begin late Friday afternoon or early evening with the heaviest showers tonight into early Saturday morning.

Colder air will begin to move in Saturday night into Sunday due to a strong upper-level low approaching through southern Canada.  As that low moves eastward during Monday and high pressure builds in behind it, cold northerly air will stream in keeping daytime high temperatures around 40 degrees during Monday and Tuesday.  As the center of the high-pressure ridge passes during mid-week, the forecast region returns to southern air flow and warming temperatures.

All in all, next week looks considerable quieter than what have been experiencing the past couple of weeks.  From an Air Quality perspective, I do not see any issues for the weekend or early next week.  PM-2.5 will be a mix of mostly Good to scattered Low Moderate with Ozone concentrations expected to be Good.

  EXTENDED FORECAST:

 Air Quality is expected to be mostly Good to scattered Low Moderate going into the upcoming work week.

03/31/2025 Forecast Update

FORECAST SUMMARY: Monday, March 31, 2025, through Friday, April 4, 2025

  OZONE: 8-hour average Ozone concentrations are expected to be Good (AQI Green).

 PM-2.5:  24-hour average Fine Particulate concentrations are expected to be a mixture of Good (AQI Green) to scattered Low Moderate (AQI Yellow).

FORECAST DISCUSSION

The weekend turned out to be quite wild with the ice storm up north and severe weather in the south.  I have read that six Michigan counties have over 80% power outages, Monday morning, between the two storms.

 This work week starts out quiet, but cooler, following the passage of a cold front but it looks to get bumpy again during mid-week.  Tuesday night model results suggest precipitation starting as all snow changing over to rain by daybreak south of I-96. North of I-96, surface air stays cold longer with accumulating snow and freezing rain likely.

 As Wednesday progresses, we get into a warm air sector ahead of the front with afternoon temperatures increasing into the 60’s.  Atmospheric instability will become significant with the increasing possibility of severe weather by late Wednesday.  Current models have an Enhanced Risk of severe weather (Level 3/5) south of I-96 with a Slight Risk (Level 2/5) north of I-96.  Precipitation models have rain potentials of 1-2 inches with more likely in thunderstorm downpour areas.

 Air Quality will not be an issue in this week’s forecast.  PM-2.5 will be a mix of Good to scattered Low Moderate.  Ozone once again becomes part of our forecast as we enter into April with concentrations expected to be Good.

  EXTENDED FORECAST:

 Air Quality is expected to be mostly Good to scattered Low Moderate going into the upcoming weekend.

Next forecast update:  Friday, April 4, 2025

03/28/2025 Forecast Update

FORECAST SUMMARY: Friday, March 28, 2025, through Monday, March 31, 2025

 PM-2.5:  24-hour average Fine Particulate concentrations are expected to be a mixture of Good (AQI Green) to Moderate (AQI Yellow) through Sunday, then mostly Good (AQI Green) during Monday. 

FORECAST DISCUSSION

 A warm front will push northward through the state during Friday.  That front will eventually stall out leaving most of the lower half of the Lower Peninsula in the warm air sector of the associated low-pressure system.  That will push temperatures in the warm air sector into the mid-60’s, for most of the weekend.  The front will essentially become a stationary front and will probably oscillate a little bit southward by the end of the weekend, but the lower half of the state will stay warm through Sunday. 

 Clouds and scattered precipitation will be with us through the weekend, although no severe weather or hard rains are expected.  Our experience with stalled fronts is that it can trap particulates near the ground.  Since we are starting with a relatively clean base, the region should not expect anything worse than Moderate in the more populated areas.

 The low-pressure system will eventually clear the area, Sunday night, and return us to cooler, northerly wind flow, cooler temperatures, and Good Air Quality.

EXTENDED FORECAST:

Air Quality is expected to be mostly Good going into the next work week.

Next forecast update:  Monday, March 31, 2025

03/24/2025 Forecast Update

FORECAST SUMMARY: Monday, March 24, 2025, through Friday, March 28, 2025

 PM-2.5: 24-hour daily average Fine Particulate concentrations will range generally Good (Green AQI) through mid-week with Moderates (Yellow AQI) possible late in the forecast period.

 FORECAST DISCUSSION:

 Although the calendar shows spring, winter-like conditions can be expected thanks to a low-pressure area across the northern portion of the region. Snow showers are possible across much of the state, with mixed precipitation or rain further south. Northern locations may see accumulations of snow, while little to no accumulation is anticipated further south. Along with precipitation chances, a strong northwest wind will keep temperatures cold for this time of year. As this storm system pulls away, precipitation on Tuesday should be kept to the most prone northwest flow lake effect areas. Weak high pressure moves in by mid-week, but cooler temperatures remain as we are positioned under a cool northwesterly wind pattern.

 As for air quality, the strong northwest winds on Monday will keep fine particulate levels in the Good range. As the storm system moves east Tuesday, surface winds decrease and precipitation ends; however, northwest winds at upper levels continue to prevent pollution from building up. With the anticipated weather conditions, you can expect Good air quality through Thursday. By Friday, the next storm system moves in, bringing a warm front across the southern portion of the state. There is some uncertainty on the placement this far out, but the warmer temperatures and precipitation could cause the fine particulate levels to increase into the low Moderate range, especially in locations south of or close to the boundary.

 EXTENDED FORECAST:

 The extended weather models show a warm front lifting north to south through the state Friday into Saturday. If this forecast pans out, warmer air will move into the state, along with chances for precipitation. Air quality during the first half of the weekend is expected to range from Good north of the boundary to low Moderate near and south of it.

 Next Forecast update: Friday, March 28, 2025

03/21/2025 Forecast Update

FORECAST SUMMARY: Friday March 21st, 2025, through Monday March 24th, 2025

PM-2.5:

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

FORECAST DISCUSSION:

We end this work week on a relative high note with southwesterly winds providing a boost in surface temperatures across the state. An encroaching Low-pressure system is causing these winds today and as we head into Saturday; the system crosses over Michigan and shifts winds to more northwesterly flow, dropping temperatures back into the low-to-mid-30s. With the passing of the cold front, there is a chance for isolated rain and snow showers early Saturday morning with most tapering off as the afternoon approaches. The system moves out of Michigan come late Saturday morning and what is left is mostly sunny skies and surface temperatures in the mid-30s. Michiganders will see more of the same on Sunday with a High-pressure system drifting down from Canada and shifting winds back to more southerly flow, but temperatures still hang around the upper-30s to low-40s for much of Sunday. The next precipitation-maker crosses over the state later on Sunday with a mix of rain and snow depending on where one is on the peninsulas. The upper peninsula will see a few inches of additional accumulating snow with the northern lower peninsula seeing a little less and the southern peninsula seeing mostly rain. This system will carry into early Monday with residual showers persistently hanging around for most of Monday.

For air quality, there was a resurgence of dust and smoke in the upper atmosphere this past week from southern plains states. Fortunately, however, this plume stayed in the upper atmosphere and did not make its way towards the surface unlike last weekend. For the weekend ahead, low-Moderate concentrations can be expected today due to southwesterly winds, but only for a few hours around commuting hours. Into Saturday and Sunday, PM-2.5 concentrations will hang around the Good range due to northerly winds and precipitation keeping concentrations at bay. Although it is officially Ozone season, it has not been warm enough for ample Ozone development.

EXTENDED FORECAST:

Cooler temperatures look to hang around into next week as Spring gets off to a slow start. Air quality looks to remain in the Good range.

Next Forecast update: Monday March 24th, 2025

03/15/2025 Forecast Update

FORECAST SUMMARY: Saturday, March 15, 2025, through Monday, March 17, 2025

 PM-2.5:  Saturday morning Fine Particulate concentrations have dramatically increased in SW Michigan into the USG range (AQI Orange) due to high dust transport.  We expect this to eventually transition back to mostly Good (AQI Green) to Moderate (AQI Yellow) during Sunday.

FORECAST DISCUSSION

In an unexpected development, strong winds have been pushing high levels of dust up from the southern Plaines states.  We have observed monitor readings jump as much as 50 ug/m3, over a short time, at many of our southwest monitors.  As a result, we are modifying our forecast to reflect USG in the southwest quadrant of the state, for the remainder of Saturday.  The remainder of the state will remain Moderate. 

A cold front will move through the region during the early Sunday morning hours.  The wind shift from southwest to northwest should put an end to this episode.  Concentrations should return to the Good/Moderate levels for Sunday and the remainder of the forecast period.  However, since this is a rapidly changing episode, we will continue monitoring and keep the forecast updated if conditions change.

EXTENDED FORECAST: 

Air Quality is expected to be Good to Moderate going into the next work week.

03/14/2025 Forecast Update

FORECAST SUMMARY: Friday, March 14, 2025, through Monday, March 17, 2025

 PM-2.5:  24-hour average Fine Particulate concentrations are expected to transition from mostly Low Moderate (AQI Yellow) to Good (AQI Green) during the forecast period.

FORECAST DISCUSSION

 As we enter the St. Patrick’s Day weekend, the weather will continue to be downright warm and early Spring-like.  The last couple of days, with calm winds and sunny skies, have certainly whetted our appetite for warmer weather to come and stay.

 That warm weather trend will continue through Saturday, but calm winds will yield to increasing winds as a deep low-pressure system approaches from the west.  Packed isobars will increase the Friday afternoon winds into the mid-teen range with gusts in the mid-20 mph range. 

 Early Saturday morning will experience a storm passage associated with the low-pressure system.  Any storms that do develop should move through by sunrise with warm, moist southerly flow continuing to flow.  That should keep Saturday afternoon temperatures up around 70 and we will likely see stronger, sustained winds with gusts up to the mid-40 mph range.

 Colder air arrives for Sunday with daily high temperatures back in the mid-40’s.  Fortunately, that cooling off will be short lived as zonal flow brings back warmer air into the area through the first half of the upcoming week.  Spring is coming!

 In terms of Air Quality, most of the state is experiencing Low Moderate conditions for Friday.  However, as the upcoming system moves through the state, it will act as a broom to sweep out the Low Moderates and should restore Good conditions for the remainder of the weekend. 

EXTENDED FORECAST:

 Air Quality is expected to be mostly Good going into the next week.

03/10/2025 Forecast Update

FORECAST SUMMARY: Monday, March 10, 2025, through Friday, March 14, 2025

PM-2.5: 24-hour daily average Fine Particulate concentrations will range from Good (Green AQI) to Moderate (Yellow AQI) during this forecast period.

 FORECAST DISCUSSION:

We can expect spring-like weather across Michigan this week. Above-normal temperatures and plentiful sunshine dominate Monday, but a quick cool down is expected Tuesday before warmer air makes a return mid-week. While a few locations in the north may see light precipitation late Monday into Tuesday as the boundary passes, most locations will remain dry. High pressure moving in behind the cold front sets up warm southerly winds, bringing a return to above-normal temperatures. Dry conditions with a fair amount of sunshine are also anticipated for the rest of the workweek. High temperatures by Friday are expected to range from the 50s in the north to around 70 degrees south.

The warmer temperatures and sunshine on Monday will cause snow to melt in areas where snow still exists. This increased surface moisture often produces increases in fine particulate levels; however, stronger winds developing, especially in the north where snow remains, will hamper pollution development. Good to low-Moderate fine particulate readings can be expected Monday. Northwesterly winds behind the cold front on Tuesday should keep air quality Good across the state. As temperatures increase and southerly winds develop past mid-week, fine particulate levels should also increase into the Moderate range.

The 2025 ozone season officially started on March 1st; however, we don’t typically begin forecasting for ozone until May. With the warmer temperatures expected, I wanted to mention that we expect maximum 8-hour ozone concentrations this week to remain in the Good range. As always, we will update this air quality forecast if our thoughts on the current trends change.

EXTENDED FORECAST:

The extended weather models show a strong weather system moving in for the end of the week. Despite its uncertain track and strength, this system is expected to bring showers and storms. Air quality levels higher than the Moderate range are not expected during this period.

 Next Forecast update: Friday, March 14, 2025