06/26/2026 Air Quality Forecast

FORECAST SUMMARY: Friday June 26th, 2026, through Sunday June 28th, 2026

Ozone:

Ozone concentrations are expected to be in the Good (Green AQI) to Moderate (Yellow AQI) range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good (Green AQI) to low-Moderate (Yellow AQI) range.

FORECAST DISCUSSION:

Hard to believe that June is over in just a few days and it sure is going out like a lion as temperatures look to soar next week.

Before we get there though, today, Friday, will be relatively similar to previous days this week with temperatures hanging around the low-to-mid 70s with some areas dealing with fog during the morning hours. As we go into Saturday, a High-pressure system moves into the Great Lakes which will shift our winds to east-southeasterly, aiding in a slight warm up into the upper-70s across the state. This warmup and upper-level pattern will continue into Sunday as an upper-level ridge builds in the latter half of the weekend which will be the start of the hot and humid summer temperatures Michigan will be feeling next week.

This forecast will be updated on Sunday to get a better look at early next week due to the possibility of Ozone flaring up with the hot and sunny days ahead. For this weekend, however, Ozone is expected to remain in the Good range on Saturday with increases into the Moderate range come Sunday. For PM2.5, a rather similar forecast is in store with increases into the low-Moderate are expected on Sunday, but mostly Good on Saturday.

EXTENDED FORECAST:

Both surface and upper-level temperatures are expected to increase early next week along with winds shifting to southwesterly flow. Adding clear, sunny conditions to the equation will pose a conducive environment for Ozone to develop in west Michigan and potentially southeast Michigan. The only factor that may help keep Ozone at bay will be the dewpoints, which will be in the mid-70s all next week so muggy conditions will be present. It has been observed in recent years that Ozone does not develop as it otherwise would when dewpoints reach or exceed 70 degrees. It is because of these factors that this forecast will be updated on Sunday, and possibly each day after that.

06/22/2026 Air Quality Forecast

FORECAST SUMMARY: Monday, June 22, 2026 through Friday, June 26, 2026

Ozone: 8-hour average Ozone Particulate concentrations are expected to be mostly Good (AQI Green) with a scattering of Moderate (AQI Yellow) for the forecast period.

PM-2.5: 24-hour average Fine Particulate concentrations are also expected to be mostly Good (AQI Green) with a scattering of Moderate (AQI Yellow) for the forecast period.

FORECAST DISCUSSION:

The cool weather experienced during the past week was a gift to Air Quality with concentrations of both ozone and fine particulates parked firmly in the Good category.  That trend looks to continue with a gradual warming trend throughout the week. 

The rain endured Sunday night is slowly exiting the state, Monday morning, and low-level northerly flow is ushering in slightly cooler and less humid air.  The high-pressure system building in behind the departing rain system will gain greater presence late Monday tonight and Tuesday as a mid/upper-level ridge builds over the Midwest.

The next weather feature of interest is associated with an approaching short wave which reaches the Great Lakes region Wednesday and Wednesday night.  Model consensus has the surface low tracking through the northern Great Lakes setting up a warm front/cold front progression across Michigan which will give us our next chance of showers and thunderstorms.  This system will not change our current air mass so temperatures will hold in the mid to upper 70s through Thursday.  Air Quality should stay mostly Good with scattered Moderates.

Models indicate potentially warmer temperatures this weekend/early next week.  Current projections have high pressure returning this weekend driving temperatures back into the 80’s with mostly dry conditions.  Sunday has the potential for temperatures in the upper 80’s.  While Air Quality does not appear to be an issue during this work week, the Friday forecast will have a better idea of any potential Air Quality issues for the weekend.

EXTENDED FORECAST:

With an increase in temperatures expected for the weekend, Air Quality is expected to begin a creep into the Moderate range.   It is too early to indicate any possibility of poor Air Quality for the weekend, at this time.

06/18/2026 Air Quality Forecast

FORECAST SUMMARY: Thursday June 18th, 2026, through Monday June 22nd, 2026

Ozone:

Ozone concentrations are expected to be in the Good (Green AQI) range.

PM2.5:

PM2.5 concentrations are expected to be in the Good (Green AQI) range.

FORECAST DISCUSSION:

Michiganders who were impacted by wind and rain midweek wake up to somewhat calm conditions and slowly start to dry out this Thursday morning. Residual rain showers and wind gusts are hanging around the state, however, this morning but are expected to move off to the east later in the day. Light winds and clearing skies are in place for Friday with surface temperatures slightly rebounding with the aid of sunshine. Saturday continues the slight warming trend although a small disturbance is expected to move in early in the morning which may provide rain to those in the lower peninsula. With this, winds are expected to shift more so to the WNW during the day on Saturday, so the upper peninsula will feel the cooler temperatures off Lake Superior. These winds continue into Sunday along with another disturbance which will bring rain to the lower peninsula again, in some capacity, as models are not in agreement with the exact location at this time.

With the passing of the Low-pressure system and frontal boundary that brought rain to the Great Lakes on Wednesday and Thursday, winds will predominantly be northerly this weekend with some westerly and easterly component to them. This typically provides cleaner air for both Ozone and PM2.5, when there are no wildfire impacts. Also, along with potential rain showers, temperatures are looking to remain in the 70s, at most, which is not quite warm enough for the Ozone photochemical reaction to occur, so Ozone will remain in the Good range for the weekend ahead. Looking at the Canadian wildfire map, there currently are wildfires in Canada, but nothing compares to this time last year, 2025, where we already were impacted by smoke at this point in the summer. Although winds will be northerly this weekend, wildfire smoke does not look to be an issue for PM2.5 concentrations.

EXTENDED FORECAST:

We warm up slightly to start next week, but winds still have a northerly component to them, so cooler than normal temperatures will prevail. Air quality will remain in the Good range.

Next Forecast update: Monday June 22nd, 2026

06/15/2026 Air Quality Forecast

FORECAST SUMMARY: Monday June 15th, 2026, through Thursday June 18th, 2026

Ozone:

Ozone concentrations are expected to be in the Good (Green AQI) to potentially low-Moderate (Yellow AQI) range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good (Green AQI) to low-Moderate (Yellow AQI) range.

FORECAST DISCUSSION:

Mid-June is here, which is hard to believe, but summer is in full swing after very warm temperatures last week and just below-to-near normal temperatures for the week ahead. We start off the week today, Monday, with clear skies and surface temperatures expected to hang around the 70s. Monday will be the last predominantly dry day this week until Friday with multiple rounds of rain expected to impact the Great Lakes this week. A Low-pressure system and associated rain showers move across the state on Tuesday which will see rain during the Tuesday evening timeframe. This system will also shift our winds to the north-northwest which will cool us down for the majority of the day. Wednesday will also see another system moving across the state which, potentially, may see more rain compared to Tuesday. Timing for rain on Wednesday is somewhat similar to Tuesday with showers, and potential thunderstorms, nearing the late afternoon and evening. These systems move out of the area on Thursday and Friday with Thursday seeing leftover, residual showers and Friday being mostly clear. Although not a complete washout of a week, numerous rain chances will help keep the gardens watered.

For air quality, PM2.5 continues to remain in low concentrations although upper-level smoke has been present in some quantities. Our eyes are staying peeled, though, for near-surface smoke as we move more into the summer months. Ozone looks to be mostly Good this week due to the numerous rain chances to help keep the atmosphere clean, along with the shifting winds and high temperatures remaining in the mid-70s at most. There may be some increases in the Moderate range on an hourly basis, especially on Monday and Friday, which will have clear skies, but nothing more than low-mid Moderate concentrations should be expected this week.

EXTENDED FORECAST:

The clearing trend on Friday continues into the weekend with sunny skies on Saturday and for the most part on Sunday. Air quality will remain in the Good range.

Next Forecast update: Thursday June 18th, 2026

06/12/2026 Air Quality Forecast

FORECAST SUMMARY: Friday, June 12, 2026 - Monday, June 15, 2026

Ozone: 8-hour average Ozone concentrations in the Good (AQI Green) to Moderate (AQI Yellow) range during the end of the week will improve to all Good Sunday and Monday.

PM-2.5: 24-hour daily average Fine Particulate concentrations will average mostly Good through the period; Saturday has the best chance for low-Moderate concentrations.

FORECAST DISCUSSION:

High pressure is building in behind Thursday’s cold front, which brought storms, some strong in nature, across Michigan. Westerly winds on Friday will deliver cooler, drier air, keeping temperatures mainly in the 70s and making for a pleasant end to the workweek. The next system arrives late Friday in the northwest and progresses southeast through early Sunday. A reinforcing surge of cooler air follows this boundary, bringing Sunday highs down into the 60s to lower 70s.

Ozone levels have generally ranged between Good and Moderate this week. One monitor in the far southwest briefly reached low-end USG prior to Thursday’s storms. The cooler westerly flow behind the front should limit ozone formation, keeping concentrations in the Good category on Friday. Warmer, southwesterly winds on Saturday could support some Moderate ozone, and there is a small potential for a brief period of low-end USG along portions of the central and southwest lakeshore. At this time, the risk is not high enough to justify issuing an Air Quality Alert. Cooler surface and upper-level temperatures behind the weekend boundary will support Good ozone levels Sunday and Monday.

Fine particulate concentrations have remained low this week, with most sites reporting Good AQI and only a few locations reaching low‑Moderate levels. Westerly flow and a low regional background should keep readings mostly Good on Friday. A period of southerly winds on Saturday may allow levels to rise into the low‑Moderate range across southern Michigan. However, the weekend boundary moving through the state will help disperse particulates, and Good AQI is expected again Sunday and Monday.

EXTENDED FORECAST:

Good air quality continues into the extended period.

 Next Forecast update: Monday, June 15, 2026

06/09/2026 Air Quality Forecast

FORECAST SUMMARY: Tuesday, June 9, 2026 - Friday, June 12, 2026

Ozone: 8-hour average Ozone concentrations in the Good (AQI Green) to Moderate (AQI Yellow) range are expected; with a few locations possibly reaching the low-end USG (AQI Orange) range.

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

FORECAST DISCUSSION:

An active stretch of weather is expected over the next few days, highlighted by building heat and humidity Wednesday and Thursday. Today (Tuesday), a weak low-pressure system will move through the region, producing scattered showers and thunderstorms as it passes. On Wednesday, a warm front will lift north, bringing southwest winds and a surge of hot, humid air. This boundary will support storm development—initially across northern areas earlier in the day, followed by a more organized line of storms later in the afternoon and into the night. A similar setup is expected Thursday. Early-day storms will exit eastern areas, but additional, more organized convection is likely later in the day ahead of an approaching cold front. As the front moves through overnight, winds will shift northwesterly, ushering in cooler and less humid air for Friday.

Fine particulate levels on Tuesday are running in the upper Good to lower Moderate AQI range. Increasing moisture through Thursday may allow concentrations to rise somewhat, but daily averages are still expected to remain within the lower end of the Moderate category. Conditions should improve by Friday, with fine particulate levels returning to the Good range.

On Tuesday, widespread cloud cover and periods of precipitation should keep ozone levels mostly within the Good range. However, some areas may see a few hours of clearing during the afternoon and early evening. If enough sunshine breaks through, ozone could rise quickly. Any increases are expected to remain within the Moderate range, though photochemical models suggest the potential for isolated USG readings in the southwestern portion of Lake Michigan.

A hot and humid southwest flow will prevail Wednesday into Thursday, and periods of thunderstorms are expected across the region. Forecast guidance indicates a break in storms during the daytime hours both days, allowing for at least some clearing. The combination of warm surface and upper‑level temperatures and continued southwest flow would typically support ozone formation. However, dew points are expected to reach the 70s, and moisture levels this high generally limit ozone production. At this time, ozone levels are not expected to exceed the Moderate category. That said, photochemical models still indicate the potential for a few hours of USG readings along portions of the west Michigan lakeshore. If updated model guidance on Wednesday morning suggests a shift toward more widespread USG ozone on Wednesday or Thursday, we will update this forecast accordingly.

EXTENDED FORECAST:

A return to Good air quality is expected late in the week.

 Next Forecast update: Friday, June 12, 2026

06/08/2026 Air Quality Forecast

FORECAST SUMMARY: Monday, June 8, 2026 - Tuesday, June 9, 2026

 Ozone: 8-hour average Ozone concentrations in the Good (AQI Green) to Moderate (AQI Yellow) range are expected.

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

 FORECAST DISCUSSION:

 High pressure will dominate central and eastern sections of the region to start the week, while an approaching system spreads increasing cloud cover across the west and brings precipitation to central and western portions of the Upper Peninsula. With a low background pollution level and southeasterly flow in place, ozone concentrations are expected to remain in the Moderate range on Monday. A developing low pressure system will move through on Tuesday, producing showers and thunderstorms across most areas. Abundant moisture will support periods of heavy rainfall within the stronger storms. In the system’s wake, southwesterly winds will usher in a hot and humid airmass for Wednesday and Thursday. While there is some uncertainty regarding storms mid‑week, the environment appears favorable for thunderstorm development.

 Fine particulate levels early Monday are generally running in the Good range. Increasing moisture through the day should allow fine particulate concentrations to increase; however, daily averages are not expected to exceed the lower end of Moderate. With more sunshine expected across central and eastern areas on Monday, ozone may also climb into the Moderate category. On Tuesday, widespread clouds and precipitation should keep ozone mostly in the Good range. However, some model guidance suggests the southwest corner of the state may clear out on Tuesday. If that occurs, Moderate ozone would be possible in that area.

 A muggy southwest flow will be in place from Wednesday into Thursday, and periods of thunderstorms are expected across the region. Current forecast models suggest a break in storms during the day Wednesday, with at least some clearing possible. The combination of warm surface and upper‑level temperatures, along with a southwest flow, is generally supportive of ozone development. However, dew points are forecast to be in the 70s, and moisture levels that high typically suppress ozone formation. While ozone is not expected to exceed the Moderate category, conditions are marginal enough that the setup warrants another evaluation on Tuesday.

 EXTENDED FORECAST:

Moderate air quality could persist at times through the extended period.

 Next Forecast update: Tuesday, June 9, 2026

06/06/2026 Air Quality Forecast

FORECAST SUMMARY: Saturday, June 6, 2026 through Monday, June 8, 2026

Ozone: 8-hour average Ozone Particulate concentrations are expected to be a mix of Good(AQI Green) to Moderate (AQI Yellow) for the forecast period.

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

FORECAST DISCUSSION

Friday afternoon and overnight rains were a welcome relief to the drier weather of the previous couple of weeks.  While those rains did provide some cleanout of the dirty air from Thursday, there was still some concern for Saturday as the cloud cover eventually clears.  The models are indicating potential issues in the very southwest tip of the state.   However, lingering cloud cover and showers appear to last long enough before winds shift to the cleaner directions of west and northwest.  As such, we will be keeping the lakeshore area Moderate but will keep an eye for any unexpected surges of ozone.

Sunday will be under a northerly wind regime and should not present any Air Quality issues.  Winds veer from northerly to south-easterly during Monday.  While some downwind stations of Detroit, such as Flint, may see a creep in ozone, there is no indication, at this time, of widespread USG.

True summer weather is in store for next week with 90-degree weather and potential Air Quality issues.

EXTENDED FORECAST:

Air Quality is expected to be Good to Moderate to begin the upcoming work week with the potential for deteriorating Air Quality by Thursday.

Forecast updated by Jim Haywood: Saturday, June 6, 2026

06/05/2026 Air Quality Forecast

FORECAST SUMMARY: Friday, June 5, 2026 through Saturday, June 6, 2026

 Ozone: 8-hour average Ozone Particulate concentrations are expected to be a mix of Good (AQI Green) to Moderate (AQI Yellow) for the forecast period.

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

  FORECAST DISCUSSION

Despite a clean background for most of the week, Thursday’s Air Quality was a rocky road with the majority of the state’s monitors unexpectedly crossing into the USG range.  Seeing the numbers climbing early in the day, ADQ did upgrade the forecast along the western lakeshore and Detroit area to USG although it was too late to issue an effective Action Day Alert.

Fortunately, that was a one-day event as clouds and showers move in along the lakeshore Friday morning and slowly expand eastward through the day.  Severe weather does not look to be an issue, but potential rainfall amounts could reach an inch or better in some areas. 

 That said, the predicted rain stops late Saturday morning, and clouds clear out in Southwest Michigan for the afternoon.  It is unsure how much of a clean out we will get from the rain and a gradual wind shift from west to northwest, so I tend to review the conditions Saturday morning and update the forecast, at that time.

  EXTENDED FORECAST:

 Air Quality is expected to be Good to Moderate for the remainder of the weekend.

06/01/2026 Air Quality Forecast

FORECAST SUMMARY: Monday, June 1, 2026 through Friday, June 5, 2026

 Ozone: 8-hour average Ozone Particulate concentrations are expected to be Good (AQI Green) early in the week transitioning to Moderate (AQI Yellow) for the remainder of the forecast period.

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

  FORECAST DISCUSSION

 Despite being under some of the strongest solar radiation of the year as we enter meteorological summer, our Air Quality has been remarkably Good.  This can be attributed to several factors such as wind blowing in from clean regions, cooler temperatures, and low humidity. 

 Those dynamics should remain in play through mid-week, at least.  Beginning Thursday, the large semi-stationary high-pressure ridge which has been responsible for our great weather for the past two weeks will finally migrate east and our wind pattern will shift to a more southern component.  That means we can expect a modest rise in surface temperatures and humidity, although the air will still be relatively dry for this time of year.  With that shift, we can expect a slow creep upwards in ozone concentrations although with the clean background, I am not expecting any immediate widespread excursions into USG territory. 

 For Fine Particulates, a check of Canadian wildfires and observed smoke is showing relatively low activity for this time of year.  Crossing fingers and hoping that trend continues although drier conditions are expected.

 I will tempt fate by writing this forecast through Friday.  However, I will be closely checking end-of-week conditions and will upgrade this forecast, as necessary.

  EXTENDED FORECAST:

 Air Quality is expected to be Moderate entering the weekend as temperatures and humidity continue to increase.

 Next forecast update: Friday, June 5, 2026

05/29/2026 Air Quality Forecast

FORECAST SUMMARY: Friday May 29th, 2026, through Monday June 1st, 2026

Ozone:

Ozone concentrations are expected to be in the Good (Green AQI) to Moderate (Yellow AQI) range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good (Green AQI) to low-Moderate (Yellow AQI) range.

FORECAST DISCUSSION:

Meteorological summer is on the horizon as June 1st kicks off the next work week. With the change in seasons approaching, Mother Nature has flipped a switch over the Great Lakes, going from wet and cooler conditions to warm and clear skies in a matter of weeks. An omega block pattern has set up in the Midwest which has High-pressure influencing our weather for the better part of a week or longer. Sunshine and even more sunshine is expected over the coming days to potentially a week and a half due to this atmospheric set up. Going more in depth, an omega block is when a High-pressure system sets up with two Low-pressure systems on either side of the High. This forces the jet stream to form a shape that looks like the Greek letter ‘omega’, hence the name omega block. This then forces weather systems around the High-pressure, providing clear conditions for those under the High. Once a system like this forms, it typically hangs around for multiple days or even weeks. This is the reason for clear skies, light winds and temperatures in the 70s across Michigan this upcoming weekend and into next week.

For air quality, with the current weather regime in place, wind direction will predominantly be northwesterly to northeasterly this weekend which will provide cleaner air. However, since we will be in the same airmass for numerous days, pollutant buildup may occur so our eyes will be watching both PM2.5 and Ozone concentrations this weekend and into next week. As of now, PM2.5 and Ozone concentrations are expected to remain in the Good to Moderate range, but if any conditions warrant an update to this forecast, an update will be made.

EXTENDED FORECAST:

Clear skies and warm temperatures remain throughout the next week. Air quality will be in the Good to Moderate range to start, but with temperatures increasing mid-to-late next week, Ozone may become an issue.

Analysis of Ozone development on May 27th:

In total, six Ozone monitors exceeded the Unhealthy for Sensitive Groups (USG) range for an 8-hour average on Wednesday May 27th. Four of those monitors were in west Michigan (Cassopolis, Coloma, Kalamazoo and Jenison) with the remaining two in southeast Michigan (Ypsilanti and Tecumseh). Models and forecast guidance on Tuesday looking at Wednesday suggested a few hours exceeding the USG range, but overall 8-hour averages were expected to remain in the Moderate range. Also, northwest to northeast winds were expected to set up in the mid-afternoon which would inhibit additional Ozone production. However, looking at the atmospheric set up on Wednesday the 27th, for inland west Michigan, a budding theory could be that persistently light to minimal winds near the surface allowed for Ozone to develop under clear skies and an already dirty airmass from the day before with necessary precursors in place. Whereas the lakeshore monitors of Holland and Muskegon, both of which were Moderate, were impacted by a building northwest wind coming off the lake which helped to keep the air cleaner, therefore less Ozone development. For southeast Michigan, winds were already shifting to the east-northeast by early afternoon, so areas to the southwest of Detroit were impacted by Ozone more than metro Detroit monitors due to precursor drift along with high-level clouds over metro Detroit. This has been seen before but on rare occasions. With numerous variables that go into the Ozone photochemical reaction, there seems to often be additional factors at play to keep us forecasters on our toes.

Next Forecast update: Monday June 1st, 2026

05/26/2026 Air Quality Forecast

FORECAST SUMMARY: Tuesday May 26th, 2026, through Friday May 29th, 2026

Ozone:

Ozone concentrations are expected to be in the Moderate (Yellow AQI) to Unhealthy for Sensitive Groups (Orange AQI), on an hourly basis, range.

PM2.5:

PM-2.5 concentrations are expected to be in the Good (Green AQI) to low-Moderate (Yellow AQI) range.

FORECAST DISCUSSION:

The unofficial start of summer has come and gone, with beautiful weather on the horizon. Today, Tuesday, will be the warmest day of this week with the 70s and 80s ranging across Michigan. High-pressure is currently sitting to our south over Inidiana which is providing clear skies and light southerly winds. Throughout today, however, the pressure system will drift off to the east which will allow two separate systems to sandwich Michigan, with one to the north and the other to the south. As the front associated with the southern system moves closer, clouds will start to build in the southern half of the state this Tuesday afternoon. The front to the north, as it moves in, may cause pop-up showers come Wednesday afternoon and evening. Once both of the systems move out of the Midwest, High-pressure moves back in on Thursday, which will clear the skies once again with light northerly winds. More of the same on Friday with north-northeast winds with temperatures in the 70s across the state. Relatively quiet weather continues for the foreseeable future with Thursday and Friday being the starting point.

For air quality, PM2.5 looks to remain in the Good to low-Moderate range, especially once winds shift to more northerly flow. With Tuesday having southerly flow, low-Moderate PM2.5 concentrations can be expected, but once the fronts move through along with the wind shift, Good concentrations will prevail. Ozone has been creeping up in the last day or so due to warming temperatures, southerly flow, and clearing skies. Ozone concentrations will be in the mid-to-high Moderate range today with some lakeshore areas potentially seeing hourly Unhealthy for Sensitive Groups (USG) concentrations. These concentrations have been building in the current airmass since yesterday with two monitors, Muskegon and Holland, exceeding the USG range yesterday for an 8-hour average. With clouds looking to build this afternoon in the southern portion of the state, Ozone production should be cut off from the lack of sunlight needed for the Ozone photochemical reaction to occur. Although there may be hourly concentrations in the USG range, widespread 8-hour averages exceeding the USG range are not expected. As mentioned above, winds shift to more northerly flow tomorrow afternoon through the rest of the week, so cleaner air will help keep Ozone development at bay. However, air quality will be monitored daily due to a long-lasting airmass that will persist over the state for numerous days with High-pressure sitting over the Great Lakes.

EXTENDED FORECAST:

High pressure persists throughout the weekend with temperatures ranging in the 70s. Air quality will be monitored as we will be in the same airmass for multiple days.

Next Forecast update: Friday May 29th, 2026

05/22/2026 Air Quality Forecast

FORECAST SUMMARY: Friday, May 22, 2026 - Tuesday, May 26, 2026

Ozone: 8-hour average Ozone Particulate concentrations start the period in the Good (AQI Green) range. Moderate (AQI Yellow) is possible starting early next week.

PM-2.5: 24-hour daily average Fine Particulate concentrations in the Good range Friday and Saturday, could increase into the Moderate Sunday through the end of the forecast period.

FORECAST DISCUSSION:

High pressure will keep most of Friday dry and cool. As we head into the holiday weekend, an upper‑level system brings a few chances for rain. The best chance for showers arrives late Friday through Saturday as a couple of disturbances move through the region. Another weak system on Sunday may bring a few spotty showers or storms, but many areas will stay dry. For Memorial Day, high pressure returns, although a bit of afternoon instability could spark some isolated precipitation. Temperatures warm through the period: highs in the 60s on Friday rise into the 70s this weekend, reaching the 70s to low 80s early next week.

Air quality starts off in the Good category for both ozone and fine particulate levels. A cool easterly wind will help keep conditions Good through Saturday. By Sunday, winds weaken and shift to the west and southwest, and temperatures begin to rise. As we head into early next week, warmer weather is expected to contribute to increasing pollution levels. Moderate levels of ozone and fine particulates may develop as early as Sunday and could continue through Tuesday. While some locations will stay in the Good range, areas along the Lake Michigan shoreline and parts of southern Michigan are more likely to see Moderate air quality.

We do not expect fine particulate levels to rise above the Moderate range during this forecast period. It’s still too early to know exactly how high ozone levels may get, but based on current weather data, we do not anticipate ozone reaching higher than Moderate. We will continue to review forecast maps and pollution model guidance through the weekend. If conditions change and we believe an Air Quality Alert is needed for Monday or Tuesday, we will update the forecast accordingly.

EXTENDED FORECAST:

Moderate air quality could persist at times through the extended period.

05/18/2026 Air Quality Forecast

FORECAST SUMMARY: Monday, May 18, 2026 - Friday, May 22, 2026

 Ozone: 8-hour average Ozone Particulate concentrations are expected to range between Good (AQI Green) and Moderate (AQI Yellow) through the forecast period.

PM-2.5: 24-hour daily average Fine Particulate concentrations will start the period mostly Moderate, with levels improving towards Good around mid-week.

 FORECAST DISCUSSION:

 A warm front will lift into the Upper Peninsula today, Monday, bringing summer‑like conditions to much of Michigan. South of the front, warm southerly winds will help drive temperatures into the mid to upper 80s. On Tuesday, a cold front sliding in from the northwest will bring a gradual cooldown from northwest to southeast. Even so, parts of southern Michigan may still reach the mid‑80s before the cooler air arrives. With the warm, humid, and unstable airmass in place, showers and thunderstorms are likely both Monday and Tuesday. A few storms could become severe, so be sure you have reliable ways to receive weather alerts. Quieter weather returns by midweek as high pressure settles in from the west. Sunshine dominates Wednesday through Friday, with temperatures on a slow warming trend.

 Air quality will begin the period with mostly Moderate fine particulate levels across the state. As cooler northwest winds develop behind Tuesday’s cold front, particulate concentrations are expected to improve. Good concentrations are expected on Wednesday and Thursday before increases toward the low Moderate range return to southern Michigan on Friday.

 Over the weekend, four monitors in west Michigan reached the lower end of the Unhealthy for Sensitive Groups (USG) ozone category on Saturday. Since then, ozone levels have ranged from Good to Moderate statewide. While warm temperatures and southerly winds can promote ozone formation, increased cloud cover and periods of thunderstorms will help limit more significant development. A mix of Good and Moderate concentrations continue on Monday and Tuesday. Statewide Good levels are forecast for Wednesday and Thursday, with a return to low‑Moderate readings possible by Friday.

 EXTENDED FORECAST:

A frontal boundary positioned south of Michigan this weekend may trigger showers and thunderstorms, mainly across the southern part of the state. During the extended period, air quality is expected to remain at or below the Moderate range.

 Next Forecast update: Friday, May 22, 2026

05/15/2026 Air Quality Forecast

FORECAST SUMMARY: Friday, May 15, 2026 through Monday, May 18, 2026

 Ozone: 8-hour average Ozone Particulate concentrations are expected to be Good (AQI Green) to Moderate (AQI Yellow) throughout the forecast period.

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

FORECAST DISCUSSION

The cooler weather of late will give way to summer like heat and humidity during the weekend which should continue through early next week.  Departing high pressure during Friday will change the wind

pattern to a southerly direction ushering in those increased temperatures and southern moisture.

We are watching these developments closely as those southerly wind directions, 80-degree temperatures and mid 60-degree dew points are approaching the ‘sweet spot’ for increased ozone.  Fortunately, there will be a flurry of regional frontal activity throughout the forecast period to keep the atmosphere well mixed.  Some storms expected along a warm front across northern Indiana Saturday afternoon could be strong to severe, but modeling indications are that they will likely remain to our south.  Sunday will be most likely be precipitation free with increasing temperatures and humidity triggering potentially strong to severe storms during Monday.

In terms of Air Quality, Fine Particulates do not appear to pose any issues as wildfire development is still at a minimum.  We could see some ozone creep, Saturday and Sunday, in areas subject to prolonged sunlight.  Models are indicating widespread Moderate concentrations and there appears to be little concern that we will see USG concentrations, although some areas could have a few hours of elevated ozone.  However, since conditions could be favorable, we will track developments during the weekend and update the ozone potential, if necessary.

EXTENDED FORECAST:

Air Quality is expected to be Good to Moderate entering the upcoming work week before we see a cool down by mid-week.

 Forecast updated by Jim Haywood: Friday, May 15, 2026

Next forecast update: Monday, May 18, 2026

05/11/2026 Air Quality Forecast

FORECAST SUMMARY: Monday, May 11, 2026 through Friday, May 15, 2026

 Ozone: 8-hour average Ozone Particulate concentrations are expected to be mostly Good (AQI Green) to scattered Low Moderate (AQI Yellow) throughout the forecast period.

 PM-2.5: 24-hour average Fine Particulate concentrations are expected to be mostly Good (AQI Green) throughout the forecast period.

  FORECAST DISCUSSION

 Cooler than average temperatures will persist during the early portion of the week but will succumb to warming temperatures by the end of the week.  One more really chilly night is on tap as a Canadian high-pressure cell remains in place with clear skies and light winds. There is a chance for frost/freeze conditions which could impact much of the state in rural areas.

 As the Canadian high-pressure system departs to the east, increasing clouds during Tuesday morning will signal the arrival of a fast-moving clipper system which is projected to bring showers in by afternoon and lasting into early Wednesday.

 High-pressure returns to the area on Thursday signaling the beginning of a warming period as winds return to a southerly component.  By the weekend, we should see temperatures in the upper 70’s to low 80’s with the chance of scattered showers.

 The cooler weather and favorable winds during most of the work week will keep Air Quality in the Good range.  The warmer weather expected by the end of the week should allow for a creep into the ozone Low Moderate range with Fine Particulates staying mostly in the Good range. 

  EXTENDED FORECAST:

 Air Quality is expected to be Good to Low Moderate entering the upcoming weekend. 

Forecast updated by Jim Haywood: Monday, May 11, 2026

Next forecast update: Friday, May 15, 2026

05/08/2026 Air Quality Forecast

FORECAST SUMMARY: Friday May 8th, 2026, through Monday May 11th, 2026

Ozone:

Ozone concentrations are expected to be in the Good (Green AQI) range.

PM-2.5:

PM-2.5 concentrations are expected to be in the Good (Green AQI) to low-Moderate (Yellow AQI) range.

FORECAST DISCUSSION:

The first full week of May has come and gone with below average temperatures, but drier conditions compared to recent weeks. The weekend ahead will see a continuation of the current weather regime with slightly warmer temperatures on Saturday for the lower peninsula. For the upper peninsula, a cold front will be making its way through the state this weekend, impacting northern areas first, so cooler temperatures are expected in those areas. With this cold front, winds will be mostly northerly in the upper peninsula, hence the cooler temperatures, while westerly winds will be over the lower peninsula, allowing for temperatures to reach the 60s. Into Sunday morning, the aforementioned front will cross over the entire state, shifting winds to predominantly northerly which will cool off all Michiganders. Pop up rain showers should be expected throughout Saturday afternoon as well with Sunday clear of any rain showers. Monday looks to be almost a copy and paste of Sunday with temperatures in the upper-40s to mid-50s and clear skies.

For air quality, Ozone continues to be a non-issue due to cooler temperatures. For fine particulate matter, northerly flow in the latter half of the weekend will clean out any residual Moderate concentrations that occur. Any Moderate concentration that pop ups will be in the low-Moderate range due to shifting winds, lack of localized wildfire smoke, and relatively clean air.

EXTENDED FORECAST:

A temperature increase is on the horizon starting mid-next week. Air quality looks to remain in the Good range for the majority of next week.

Next Forecast update: Monday, May 11th, 2026

05/01/2026 Air Quality Forecast

FORECAST SUMMARY: Monday May 4th, 2026, through Friday May 8th, 2026

Ozone:

Ozone concentrations are expected to be in the Good (Green AQI) to Moderate (Yellow AQI) range.

PM2.5:

PM-2.5 concentrations are expected to be in the Good (Green AQI) to low-Moderate (Yellow AQI) range.

FORECAST DISCUSSION:

Spring Strikes Back! At least for today, Monday, as southerly flow brings in warmer air and mostly sunny skies. On the back end of this Star Wars Day is a cold front and associated Low-pressure system which will eclipse Michigan while cooling us down and initiating rain showers across the state. West-Northwest winds will dominate the weather regime with surface temperatures lingering in the low-to-mid 50s for the majority of the week. Mid-week is expected to be mostly dry with rain chances returning for the latter half of the work week on Friday, but as of now, rain will only impact southern portions of Michigan.

For air quality, Monday will be highest day for concentrations due to warmer temperatures and southerly flow. Both Ozone and PM2.5 will cross over into the Moderate range, mostly in the more populated areas of Detroit and Grand Rapids, but wind shifts this week, along with a decrease in temperatures, will bring air quality concentrations back into the Good range.

May the forecast be with you.

EXTENDED FORECAST:

Slight temperature increases are on the horizon for the weekend ahead. Air quality will remain in the Good range.

Next Forecast update: Friday May 8th, 2026

04/24/2026 Air Quality Forecast

FORECAST SUMMARY: Friday, April 24, 2026 through Monday, April 27, 2026

 Ozone: 8-hour average Ozone Particulate concentrations are expected to be Good (AQI Green) to scattered Moderate (AQI Yellow) throughout the forecast period.

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

FORECAST DISCUSSION

 After a sneak peek into upcoming summer weather during the past few days, things will return to more seasonal conditions for the weekend.  Showers, and possible a thunderstorm, is the forecast for Friday as a cold front tracks across the state.  Potential precipitation amounts increase during the day as more moisture moves into the area with a potential up to 1.25 inches in the eastern half of the state.

 Following the cold front, the weekend looks pleasant and dry with temperatures in the upper 60’s with dew points in the 40’s.  A good weekend to get early Spring yard work done.  The next chance for rain comes from a low-pressure system moving our direction from the plains region.  Models indicate precipitation arriving Monday afternoon and evening with rainfall potential around 1.5 inches.

 The warmer weather of the past couple of days pushed ozone values into the High Moderate range. Following the Friday cold front, generally, Good Air Quality is expected throughout the state mixed with scattered Moderates. 

EXTENDED FORECAST:

 Air Quality is expected to be mostly Good entering the upcoming work week. 

Next forecast update: Monday, April 27, 2026

04/20/2026 Air Quality Forecast

FORECAST SUMMARY: Monday, April 20, 2026 through Friday, April 24, 2026

Ozone: 8-hour average Ozone Particulate concentrations are expected to be Good (AQI Green) throughout the forecast period.

PM-2.5: 24-hour average Fine Particulate concentrations are also expected to be mostly Good (AQI Green) to scattered Moderate (AQI Yellow) throughout the forecast period.

FORECAST DISCUSSION

After all the wet and stormy weather which has plagued most of April to this point, Michigan is in for a much quieter and tranquil week with a chance to begin drying out.  Monday did start out rather cold (i.e. multiple freeze warnings) but should rebound by mid-week.  Southwesterly flow returns on Tuesday and that will mark the beginning of milder and less dry air. 

The warmest temperatures should arrive by Wednesday with Thursday likely the warmest day of the week with temperatures in the mid-70’s.  Light northeasterly winds on Wednesday should keep Air Quality in the Good range but winds shifting more southerly by Thursday could result in scattered Moderate conditions.  Fortunately, with the heavy winter snowpack to our north, wildfires are yet to become a concern.  Only small, controlled fires are currently reported in the far western Provinces.

Mostly sunny skies during Wednesday and Thursday should provide a good opportunity for drying out and high river levels to begin dropping.  A weak cold front is projected to move through Michigan on Friday bringing a chance of showers and thunderstorms.

Generally, mostly Good Air Quality is expected throughout the state with only a chance of scattered Moderates during mid-week. 

EXTENDED FORECAST:

 Air Quality is expected to continue to be mostly Good entering the upcoming weekend. 

 Forecast updated by Jim Haywood: Monday, April 20, 2026