12/05/2025 Air Quality Forecast

FORECAST SUMMARY: Friday, December 5, 2025 through Monday, December 8, 2025

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

FORECAST DISCUSSION

Clear skies and calm winds produced a chilly Thursday night with temperatures down into the single digits.  Clouds are redeveloping over the area Friday morning, as the high pressure moves east and follow-up southwest winds bring clouds and eventually snow showers.

The models are indicating some concern for some light freezing drizzle around daybreak, Saturday morning.  This does not appear to be a long duration event but could be just enough to cause some minor impacts during Saturday morning travels.  Colder air comes in by mid Saturday morning and precipitation should taper off as weak high pressure builds in.

A short wave pushes through the area, Saturday night.  Combined with lake moisture, it will produce some light snow through Sunday morning in West Michigan.  Stronger high pressure will build over the area, later Sunday, and linger through Monday.

Air Quality starts out with a mix of Good and Low Moderate AQI readings.  However, with a cold snowpack and some high pressure, concentrations will likely remain in the Good to Low Moderate range.

EXTENDED FORECAST:

 Air Quality is expected to remain Good to Low Moderate entering the next work week.  The next best chance for accumulating snow occurs next Tuesday and Wednesday.

12/01/2025 Air Quality Forecast

FORECAST SUMMARY: Monday, December 1, 2025 through Friday, December 5, 2025

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

  FORECAST DISCUSSION

 Today (Monday) marks the beginning of Meteorological Winter.  Astronomical Winter occurs on December 21, which marks the shortest day of the year.  The current weather pattern is living up the winter name with colder than normal temperatures following a weekend snowfall event unmatched in many years for this time of year.

 The cold weather will continue for the foreseeable future.  In the Lower Peninsula, normal daytime high temperatures should be around 40 degrees with lows in the upper 20’s.  It is unlikely that we will see temperatures north of the freezing point during this forecast period with low temperatures potentially reaching single digits Thursday night.

 Monday morning, Air Quality starts out in the Good AQI range.  However, with a cold snowpack and lingering overnight inversions, some stagnation could drive concentrations into the Low Moderate range.

 While models are not showing any major storms heading our way, the National Weather Service is predicting a major lake effect snow event occurring on Monday night, north of Muskegon.  Other lake shore counties will probably also see some snow but to a much lesser extent.  A cold front is expected to drop south from Canada, Wednesday night, with some light snow accumulation expected.

  EXTENDED FORECAST:

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

11/24/2025 Air Quality Forecast

FORECAST SUMMARY: Monday, November 24, 2025 - Monday, December 1, 2025

PM-2.5: 24-hour daily average Fine Particulate concentrations will average mostly Good (Green AQI), with a few periods of Moderates (Yellow AQI) possible.

 FORECAST DISCUSSION:

 Quiet weather conditions start this forecast period.  On Monday, dry and seasonably warm weather is in place; however, a change is in store as we move towards mid-week.  This change begins as precipitation moves in Tuesday ahead of a developing storm system.  Temperatures will be warm enough for the precipitation to be in the form of rain.  The main weather system tracks from the Dakotas Tuesday morning to the western portion of the Upper Peninsula Wednesday morning.  Cold northwest winds behind the associated cold front switch the rain to snow starting Tuesday night in the Upper Peninsula, and western portions of the area could see 12+ inches of snow from Tuesday evening into Thanksgiving morning.  As this system continues moving west, strong northwest winds cause temperatures to plummet from northwest to southeast through the state.  The cold northwest winds over the relatively "warm" lake waters likely produce significant accumulations of snow in the most prone northwest flow areas of the Upper Peninsula and northern Lower regions.  Those traveling for the coming Thanksgiving holiday should check local weather conditions prior to heading out.  Cold northwest winds continue into Friday, and lake effect snow continues as well.

 Air quality levels Monday into Tuesday could reach the Moderate range, especially across southern areas, thanks to the warmer temperatures and a southerly wind flow that lingers into Wednesday.  The cold northwest winds that develop from northwest to southeast from late Tuesday into Wednesday will produce Good air quality statewide by Wednesday, and good air quality readings will continue through Friday.

 EXTENDED FORECAST:

Extended forecast models are showing high pressure moving over the state Saturday.  This pattern change ends lake effect snow for a period of time; however, the next weather system could bring rain/snow back into the forecast starting on Sunday, lasting into Monday.  Lighter winds turn southwest winds late in the forecast period.  This flow could allow for Moderate fine particulate readings, especially in the more urban portions of the state.

Next Forecast update: Monday, December 1, 2025

11/21/2025 Air Quality Forecast

FORECAST SUMMARY: Friday, November 21, 2025 through Monday, November 24, 2025

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

  FORECAST DISCUSSION

The passage of a cold front, early Friday morning, will give way to high pressure building in behind the front.  This will encourage mostly clear skies, for the weekend, with the added benefit of moderate temperatures staying pretty consistent.  In fact, temperatures are expected in the low 50’s from Sunday through Tuesday.  Current Moderate AQI readings in the lower half of the Lower Peninsula should give way to mostly Good AQI.

Current model runs are indicating a short wave expected to develop late Monday and continuing into Tuesday with precipitation staying all rain.  With the exception of potential lake effect rain/snow showers, the long range forecasts are currently showing the weather behaving during the holiday travel period.  Keeping fingers crossed for that forecast prediction to hold true.

Friday marks exactly one month until the winter solstice occurs.  Fortunately, the loss of daylight hours is slowing to around one minute per day.  Following the winter solstice, (December 21), the days will start getting longer again, slowly at first, then gaining momentum. 

Air Quality should not be an issue as fine particulate matter levels stay mostly Good with a few scattered Low Moderates.

  EXTENDED FORECAST:

 Air Quality is expected to remain Good to Low Moderate entering the upcoming work week.

11/17/2025 Air Quality Forecast

FORECAST SUMMARY: Monday, November 17, 2025 through Friday, November 21, 2025

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

FORECAST DISCUSSION:

A low-pressure system, currently in the central Plaine states, as of Monday morning, will migrate eastward and impact our weather into midweek.  The system will pass to our south, with a warm front stretching across the Ohio Valley.  As the warmer air to our south overrides the colder air at the surface, we can expect some precipitation to form in the southern half of the Lower Peninsula late Monday night through most of Tuesday.  Drier air at the surface will evaporate much of the early precipitation, but as the air becomes more saturated, precipitation will eventually reach the surface.  The first precipitation to reach the ground will likely be snow, which will transition to sleet and rain as daytime temperatures warm.  The potential for some lingering drizzle/freezing drizzle could last into Tuesday evening.

The next chance for some precipitation occurs Thursday into Friday morning, when we will likely see some rain, thanks to a northern trough moving through the region.  Current model projections indicate the weekend should be dry.

Air Quality should not be an issue as fine particulate matter levels stays Good with a few scattered Low Moderates.

EXTENDED FORECAST:

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

11/14/2025 Air Quality Forecast

FORECAST SUMMARY: Friday, November 14, 2025 - Monday, November 17, 2025

PM-2.5: 24-hour daily average Fine Particulate concentrations will average mostly Good (Green AQI), with only a few Moderates (Yellow AQI) possible Friday into Saturday.

FORECAST DISCUSSION:

Dry weather and unseasonably warm temperatures start this forecast period.  The dry, warm conditions can be attributed to high pressure and an upper-level ridge south/southeast of the state producing a warm southerly flow over the region.  High temperatures on Friday will range in the 50s, and readings could reach the low 60s in the south on Saturday.  The next weather system is a low-pressure area on Saturday tracking from west to east just north of Lake Superior.  This system brings a cold front from northwest to southeast throughout the day.  Precipitation will accompany this weather system; however, southern areas may remain dry.  What will be most noticed, however, are the strong northwesterly winds and cold air moving in behind this boundary.

Southerly winds statewide on Friday, lasting into Saturday in the south, could allow for low-Moderate daily averages of fine particulate.  Any increase in pollution will improve from late Saturday to Sunday as strong northwesterly winds develop behind the cold front.

EXTENDED FORECAST:

Extended forecast models show dry conditions lingering into the first half of next week.  Fine particulate levels during this period are not expected to reach higher than low-Moderate.

Next Forecast update: Monday, November 17, 2025

11/10/2025 Air Quality Forecast

FORECAST SUMMARY: Monday, November 10, 2025 - Friday, November 14, 2025

PM-2.5: 24-hour daily average Fine Particulate concentrations will average mostly Good (Green AQI), with only a few Moderates (Yellow AQI) during the forecast period.

 FORECAST DISCUSSION:

 The first taste of winter arrived this past weekend as much of the state saw its first accumulating snowfall of the season.  The snowfall happened as a disturbance passed through on Sunday.  Strong north winds behind this system are creating lake effect snow, with more accumulations expected today, Monday, in the most prone north/northwest regions.  Lake effect snow should taper off Tuesday as high pressure moving in switches winds to a south/southwesterly direction for a short time.  Weak disturbances in the northwesterly upper-level flow, however, will keep small chances for precipitation through mid-week.  Temperatures will be warm enough for the precipitation to fall mostly as rain.

 As for air quality, northwesterly winds will keep fine particulate levels generally Good, aside from a low-Moderate average possible in the more urban locations.  By Thursday, high pressure moves overhead, and wind speeds decrease.  Daily fine particulate concentrations may reach the low-Moderate range from Thursday into Friday.

 EXTENDED FORECAST:

Extended models show dry conditions through most of Saturday and high temperatures ranging in the 40s and 50s through the weekend.  The next weather system could bring precipitation back into the forecast from late Saturday to Sunday.  Currently, temperatures look to be warm enough for rain in lieu of snow.  Air quality in the extended period is not expected to reach higher than the low Moderate range.

Next Forecast update: Friday, November 14, 2025

11/07/2025 Air Quality Forecast

FORECAST SUMMARY: Friday, November 7, 2025 through Monday, November 10, 2025

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

  FORECAST DISCUSSION

 The biggest feature of the weekend forecast will be a preview of our upcoming winter weather.  The dreaded “S” word has finally made it as part of the forecast discussion.  Snow is expected to finally arrive Saturday night with greatest accumulations, 1 to 2 inches, occurring along or just south of a line running from Kalamazoo to Lansing.  Models indicate most accumulations would occur between midnight and sunrise Sunday.

 With the marginally freezing temperatures and abundance of moisture, I expect that snow to be wet and sloppy with resulting accumulations likely minimal as the ground is still relatively warm.  Thus, we will likely see more snow in the air than on the ground.

 By Sunday night, we transition from synoptic snow (i.e. low pressure related) to Lake Effect snow.  Snow will be much fluffier as we experience cold north-northwesterly flow over the relatively warmer waters of Lake Michigan.  This will keep the majority of the accumulations limited to the southwest Lower Peninsula lakeshore counties.  The persistence of these winds and snow showers will likely linger into Monday and possibly affect the Monday morning commute.  Temperatures should rebound enough during Tuesday to keep any lingering precipitation in liquid form.

 Air Quality should not be an issue as fine particulate matter levels stays Good with a few scattered Low Moderates.

  EXTENDED FORECAST:

 Air Quality is expected to remain Good to Low Moderate entering the upcoming work week.

11/03/2025 Air Quality Forecast

FORECAST SUMMARY: Monday November 3rd, 2025, through Friday November 7th, 2025

PM-2.5:

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

FORECAST DISCUSSION:

The first full week of November will have quite a back-and-forth in terms of pressure systems as an active pattern is in store for us Michiganders this week. As we wake up this Monday morning, a cold front is drifting off to the east and bringing the showers currently over the lower peninsula with it. On the backside of this frontal boundary is a high-pressure system which will drift northwards, bringing warmer temperatures along for the ride. This will precede a warm front associated with a low-pressure system which will impact us on Wednesday and provide rain showers for much of the state. Like a pinball machine, we bounce back under high-pressure and clearing skies on Thursday before, yet another low-pressure and associated precipitation make a return for Friday which will see stronger winds and more rain compared to Wednesday.

Due to the back-and-forth pressure systems, along with changing wind directions, PM-2.5 concentrations are not expected to be an issue this week due to the consistent change in air mass. On some smoke models, though, there appears to be the faintest signature of wildfire smoke over the state on Wednesday, but nothing more than a few low-Moderate scattered in northern areas. Overall, PM-2.5 concentrations will remain Good.

EXTENDED FORECAST:

Northerly winds cool us down into the 40s and 30s for the weekend ahead. Air quality should remain in the Good range.

Next Forecast update: Friday November 7th, 2025

10/31/2025 Air Quality Forecast

FORECAST SUMMARY: Friday, October 31, 2025 through Monday, November 3, 2025

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

  FORECAST DISCUSSION

Today, October 31, marks the final day of the 2025 Ozone season.  In recap, although it was a warmer summer, overall elevated ozone days were below normal. 

As we enter November, we are at the time of year where Air Quality generally does not cause any problems.  The current weather patterns are following seasonal normals with daily highs in the mid-50’s and nighttime lows in the 30’s.  Precipitation amounts during the Fall months have also been pretty close to climatic normal.

This weekend will be no different. The upper-level low pressure cell, currently influencing the area and continuing to provide cloud cover, will continue lifting northeast across the lower Great Lakes today.  Lake effect showers look to continue, especially for areas downwind of Lake Michigan in West Michigan.

Saturday remains cool as a low-pressure cell spins over southwest Michigan before being edged out by high-pressure ridging during Sunday.  Monday will likely experience a fast-moving clipper system before high pressure builds back in during Tuesday.

Air Quality should not be an issue as fine particulate matter levels stay Good with a few scattered Low Moderates.

  EXTENDED FORECAST:

 Air Quality is expected to remain Good to Low Moderate entering the upcoming work week.

10/27/2025 Air Quality Forecast

FORECAST SUMMARY: Monday, October 27, 2025 through Friday, October 31, 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 Good (AQI Green) to scattered Low Moderate (AQI Yellow).

  FORECAST DISCUSSION

 As we wind up October, we also wind up the 2025 Ozone season.  In recap, although it was a warmer summer, elevated ozone days were below normal.  A good thing!  The wildfire season certainly gave us fits, so it was nice to have a relatively good ozone season.

 We are at the time of year where Air Quality generally does not cause any problems.  Ozone season is ending, and Canadian wildfires are in retreat.  Weather patterns can still be active, however, and hurricane season is still raging in the Caribbean. 

 The weather for this week is expected to be seasonal and mostly dry for the first half of the week.  A retreating high-pressure system is giving way to an approaching low-pressure system predicted to move up the Mississippi/Ohio River valleys later in the week.

 The retreating high-pressure will continue to provide clear skies through Wednesday as the low-pressure system drives northeast through the Mississippi/Ohio River valleys.  Being sandwiched between the high-pressure and low-pressure cells will give us brisk easterly winds through much of the early half of the week.  As the low-pressure cell passes beneath us later in the week, we will have the best shot at some Halloween precipitation although not predicted to be heavy.

  EXTENDED FORECAST:

 Air Quality is expected to remain Good to Low Moderate entering the upcoming work week.

10/24/2025 Air Quality Forecast

FORECAST SUMMARY: Friday October 24th, 2025, through Monday October 27th, 2025

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:

A Pure Michigan Fall weekend is ahead for the last weekend of October with clear skies and temperatures right around seasonal norms. After a few days of dreary and rainy weather, dry air via high-pressure moved in overnight which is reasoning for why most of us are under blue skies this Friday morning.

This high-pressure will persist through the weekend providing light winds and easterly to southeasterly flow which will keep our surface temperatures right what seasonal averages for this time of year. Going into Saturday night, it appears some precipitation tries to develop but a dominating dry airmass will dissipate any chance for precipitation to fall. Speaking of Saturday night, whether you are a Michigan fan or Michigan State fan (Go Blue!) it will be perfect football weather for the two rivals to square off in East Lansing. More of the same on Sunday as the high-pressure hangs around throughout the weekend and into the start of the next work week.

For air quality, there is one more full week for the official Ozone season as Ozone continues to be a nonissue as our surface temperatures continue to slowly decrease. With light winds in place, especially during the mornings, it would not be surprising to see an increase of PM-2.5 concentrations in the populated areas. As each day carries on, however, these concentrations are expected to decrease.

EXTENDED FORECAST:

The last full work week of October starts off with seasonal average temperatures and clear skies. Air quality will continue to remain in the Good range.

Next Forecast update: Monday October 27th, 2025

10/20/2025 Air Quality Forecast

FORECAST SUMMARY: Monday October 20th, 2025, through Friday October 24th, 2025

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:

After a rather wet and dreary weekend, Michiganders wake up to some sunshine and quiet conditions this Monday morning. Currently we are in a lull period between two systems with the second system expected to impact us tomorrow, Tuesday, and into Wednesday. Rainy conditions return to the entire state later on Tuesday after a cold front moves through earlier in the day. This will drop temperatures down to around seasonal norms and shift our wind direction to more northwesterly. With the upper 40s being forecasted as high temperatures on Wednesday, and lake temperatures still in the upper 50s, lake-effect rain showers will impact the state predominantly on Wednesday. This is the same process as lake-effect snow, but with temperatures still a bit above freezing, the form of precipitation will be rain. Lingering lake-effect showers persist into Thursday before we dry out on Friday and head into the weekend.

For air quality, there are two more weeks left in the official Ozone season as Ozone does not look to be a threat this week as temperatures hang around in the 40s to 50s. Aside from early morning commutes, PM-2.5 does not look to be a threat either as breezy conditions return midweek which will help to clean out any particulate build up.

EXTENDED FORECAST:

The ending of this week persists through the weekend with seasonal norms on the docket. Air quality is expected to remain in the Good range.

Next Forecast update: Friday October 24th, 2025

10/13/2025 Air Quality Forecast

FORECAST SUMMARY: Friday October 17th, 2025, through Monday October 20th, 2025

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:

After numerous weekends of picture-perfect, above normal Fall weekends, us Michiganders are in store for a rather opposite weekend ahead: rainy and windy. Some areas in the north will see rain tapering off this Friday afternoon with a clear evening for most of us. Come Saturday, however, the majority of the Great Lakes region will be impacted by a Low-pressure system making its way into the area, which will be influencing our day-to-day for the remainder of the weekend. A quick-hitting warm front will move through the area early Saturday morning which will provide above-normal temperatures during the day on Saturday, before temperatures drop come Saturday evening with a trailing cold front. In between the two fronts, rain will be hit or miss in most areas with wind gusts increasing throughout Saturday afternoon and evening. Come Sunday, the ‘Gales of November’ look to come early as the Low-pressure system moves over top of Michigan providing gusty conditions across the Great Lakes. This is due, in part, to the aforementioned Low-pressure system and a High-pressure system out to the east, so the pressure gradient will be sandwiched between the two, causing the windy conditions. With the Low-pressure over us on Sunday, persistent rain across the state, coupled with windy conditions, will make for a great inside-kind-of-day.

For air quality, Good concentrations are expected throughout the weekend with Ozone not being a threat due to cloudy conditions and cooler temperatures. The windy conditions will also help to keep PM-2.5 concentrations in the Good range due to ample dispersion and a clean air mass.

EXTENDED FORECAST:

Breezy conditions continue into next week with a slight increase in temperatures before dropping down to seasonal norms. Air quality will remain in the Good range.

Next Forecast update: Monday October 20th, 2025

10/10/2025 Air Quality Forecast

FORECAST SUMMARY: Friday, October 10, 2025 through Monday, October 13, 2025

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

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

FORECAST DISCUSSION

In many ways, this weekend will be much like last weekend with the difference being some 20 degrees cooler. Once we get past some rain chances this evening, thanks to a passing cold front, clear skies and dry air returns thanks to the next high-pressure system building in behind the front.

This week felt more like traditional fall weather with daily highs in the 60’s and chilly 30 degrees weather at night.  Some light frost occurred in low lying areas and roof tops but no killing frost.  The rain expected Friday evening should be light in nature as this system does not have a great deal of moisture.  Rainfall amounts are expected, however, to increase the further north you go.

Once the approaching high pressure pushes out the Friday night cold front, clear skies and slightly warmer temperatures settle in.  Clear skies with daily highs in the upper 60’s and low 70’s with nighttime temperatures in the 40’s should persist for most of the upcoming work week. 

In terms of Air Quality, I am not anticipating any issues during this period and AQI levels should range between mostly Good to scattered Low Moderate.

EXTENDED FORECAST:

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

10/06/2025 Air Quality Forecast

FORECAST SUMMARY: Monday, October 6, 2025 through Friday, October 10, 2025

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

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

 FORECAST DISCUSSION

 In the spirit of “All Good Things Must Come to an End”, Monday will be the last day of the extended late summer weather we have been enjoying.  Current temperatures, running 15-20 degrees above normal, will come to an end as an advancing cold front migrates through the region Monday night and Tuesday. 

 This front will collide with deep moisture streaming up from the Gulf.  Atmospheric instability is limited, but models are showing some convection which could contain brief heavy downpours and gusty winds.  Heaviest precipitation looks to be in a line stretching from Holland to the northern Thumb area.  Rainfall amounts in this zone will likely range from three-quarters inch to an inch.  Other areas should expect about half an inch of rain.

 High pressure will move in Tuesday evening with dry, northerly flow and more seasonable temperatures.  With clear skies and dry conditions, we can expect high temperatures in the mid-60’s and low temperatures in the upper 30’s and low 40’s.  Remote low-lying areas could see some light frost.  These conditions should prevail through the remainder of the forecast period.

 In terms of Air Quality, I am not anticipating any issues during this period and AQI levels should range between mostly Good to scattered Low Moderate.

 EXTENDED FORECAST:

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

10/03/2025 Air Quality Forecast

FORECAST SUMMARY: Friday, October 3, 2025 - Monday, October 6, 2025

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

PM-2.5: 24-hour daily average Fine Particulate concentrations will average mostly Moderate.

FORECAST DISCUSSION:

The big story for this forecast period will be the unseasonably warm temperatures. Highs today (Friday) through Sunday are forecast to reach into the 80s across most of the state. This is due to high pressure and southerly winds, which increase as the weekend progresses. As the new week starts, a frontal boundary will be moving into the Upper Peninsula. As this system moves in, it brings with it some much-needed rain Monday up north, pushing south later Monday into Tuesday.

As for air quality, the warm surface and upper-level temperatures could allow for Moderate ozone levels this forecast period. However, with it being so late in the season, readings higher than Moderate are not anticipated. Southerly winds will also allow fine particulates to increase, with mostly Moderate levels expected through the period.

EXTENDED FORECAST:

Extended models show a cold front passing northwest to southeast through the state Monday. This boundary brings with it precipitation and cooler temperatures. Air quality in the Moderate range should improve back towards the Good range on Tuesday.

Next Forecast update: Monday, October 6, 2025 

9/29/2025 Air Quality Forecast

FORECAST SUMMARY: Monday, September 29, 2025 - Friday, October 3, 2025

Ozone: 8-hour ozone concentrations are expected to range mostly Good (Green AQI), with some scattered Moderates (Yellow AQI) possible.

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

FORECAST DISCUSSION:

As September ends and we move into October, warm and dry conditions continue across Michigan. Upper-level ridging and surface high pressure are the dominating weather features this week aside from a weak, dry front passing north to south on Tuesday. Temperatures behind this boundary will decrease to around 70 degrees between Tuesday and Thursday; otherwise, highs around 80 degrees are likely. Clear skies allow for favorable radiational cooling at night, and lows through the week range between the mid-40s and low-50s.

Air quality is not expected to be an issue during this forecast period, and we anticipate that AQI levels will range from Good to low-Moderate.

EXTENDED FORECAST:

Extended models show a cold front possibly bringing precipitation to northern locations this coming weekend. Warmer temperatures continue in the long term, with air quality concentrations remaining between Good and low-Moderate.

Next Forecast update: Friday, October 3, 2025

9/26/2025 Air Quality Forecast

FORECAST SUMMARY: Friday, September 26, 2025 through Monday, September 29, 2025

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

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

FORECAST DISCUSSION

After a mostly cloudy and wet week, conditions are shaping up to be a nice late-summer type of weekend.  After a weak low-pressure system exits the area on Friday, we will see a drying out period with low humidity and warming temperatures.

 I expect those warming temperatures to prevail through the mid-levels of the atmosphere with high-pressure dominating the region and the lack of moisture keeping most of the area dry and clear.  Afternoon high temperatures are expected in the upper-70’s and low-80’s under sunny skies with nighttime temperatures under clear skies in the mid-50’s.  Indications are that this pattern will last through the middle part of next week.

 In terms of Air Quality, I am not anticipating any issues during this tranquil period and AQI levels should range between Good and Moderate through the forecast period.

  EXTENDED FORECAST:

 Air Quality is expected to remain Good to Low Moderate entering the upcoming work week.

9/22/2025 Air Quality Forecast

FORECAST SUMMARY: Monday September 22, 2025, through Friday September 26, 2025

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 Moderate (Yellow AQI) range.

FORECAST DISCUSSION:

Much needed rain has been intermittently falling across the state for the past 24 hours with spotty rain showers expected to persist through midweek. Continuous Low-pressure systems and associated frontal boundaries look to sit over Michigan today, Monday, through Wednesday night before moving off to the east come Thursday morning. Surface temperatures slightly above seasonal norms are expected this week as well, with the exception of Wednesday, which is due to rain showers throughout the day on Wednesday. A total washout is not expected with rain totals Thursday morning expected to hover around the half inch to inch mark for areas across the lower peninsula. The upper peninsula has been receiving rain rather frequently compared to the lower peninsula and that can be seen on the drought map as the majority of the lower peninsula is in some form of drought stage. After the rain moves off to the east, however, clearing skies return for Thursday and Friday with surface temperatures returning to the mid-to-high 70s.

For air quality, the cloudy, rain skies coupled with cooler temperatures will keep Ozone concentrations at bay unlike last week where a few high-Moderate and even some Unhealthy for Sensitive Groups concentrations were observed due to the warmer temperatures. That will not be the case this week as we move closer to the end of Ozone season. Aside from morning commutes increasing PM-2.5 values, PM-2.5 concentrations do not look to be an issue this week either with Good to low-Moderate concentrations expected.

EXTENDED FORECAST:

Clearing skies and warmer temperatures return for the weekend ahead. Air quality should range between the Good and Moderate range.

Next Forecast update: Friday September 26th, 2025