07/24/2025 Forecast Update

Pollutant Overview

Ozone (O₃):
8-hour average ozone concentrations are expected to range from Good (Green AQI) to Moderate (Yellow AQI). A small chance for USG (Orange AQI) exists in southeastern and southwestern Michigan on Thursday.

Fine Particulates (PM-2.5):
PM2.5 concentrations will be Moderate across southern Michigan, with USG levels developing in the Upper Peninsula Thursday afternoon, expanding into the northern Lower Peninsula by early Friday morning. There is a possibility of short-term Unhealthy (Red AQI) spikes in localized areas.

Forecast Discussion

A frontal boundary advancing south through Michigan will be the focal point for storm development and air quality impacts over the next few days.

• Thursday: Warm and humid conditions persist with sunshine and temperatures reaching 80s in the north and 90s in the south. Heat indices may approach 100°F in parts of southern Michigan.

• Precipitation will move into northern areas late Thursday, spreading further south by early Friday as the front progresses.

As the front moves south, Canadian wildfire smoke will be pulled into Michigan. Forecast models indicate:

• Smoke entering the Upper Peninsula Thursday afternoon

• The smoke plume will drift into the northern Lower Peninsula early Friday morning, potentially reaching central areas by midday Friday.

PM2.5 levels are expected to rise into the USG (Orange AQI) range in the advisory areas. There is also a chance for hourly concentrations to briefly reach the Unhealthy (Red AQI) range. The advisory will be reevaluated Friday morning to determine if expansion further south or an extension into Saturday is necessary.

For ozone, some monitors reached low-end USG levels in southeastern Michigan on Wednesday. A similar risk exists for Thursday, particularly in southeastern and southwestern Michigan, though most areas are expected to remain in the Moderate range.

Extended Outlook

The extended forecast remains uncertain due to:

• The path and intensity of additional smoke plumes

• The timing of precipitation

• The ongoing impact of heat and humidity on air quality levels

Further forecast updates will be issued as conditions develop.

07/23/2025 Forecast Update

Pollutant Overview

Ozone (O₃):
8-hour average ozone concentrations are expected to range from Good (Green AQI) to Moderate (Yellow AQI). A small chance exists for Unhealthy for Sensitive Groups (Orange AQI), particularly in parts of southern Lower Michigan.

Fine Particulates (PM-2.5):
24-hour average concentrations will remain mostly Moderate (Yellow AQI) statewide, with potential increases due to wildfire smoke later in the forecast period.

Forecast Discussion

A frontal boundary is progressing south through Michigan, bringing a shift in weather and air quality conditions:

• On Wednesday, the front will bring precipitation to the Upper Peninsula and parts of Northern Lower Michigan, while sunny skies continue further south.

• Temperatures will rise into the 80s on Wednesday and climb into the 90s on Thursday across much of the Lower Peninsula.

• Heat indices may approach 100°F in the south on Thursday. With the increasing humidity, outdoor conditions will become uncomfortable, and heat safety precautions are advised.

For air quality:

• PM2.5 levels have remained in the upper Good to low Moderate range, and similar levels are expected through Wednesday.

• Smoke models suggest a plume of wildfire smoke may move into the Upper Peninsula Thursday afternoon, gradually pushing into southern Michigan by late Thursday into Friday. If current trends continue, PM2.5 may approach USG levels in affected regions. This will be closely monitored for potential air quality alerts.

• Ozone levels are forecast to remain Moderate, with Good conditions in the north. Sunshine and warming temperatures may allow for localized increases on Wednesday, but increased humidity and cloud cover Thursday will likely limit ozone formation. A small chance exists for isolated USG levels, though not enough to warrant a pollution alert at this time.

Extended Outlook

There is continued uncertainty in the extended forecast regarding:

• The timing and intensity of precipitation

• The trajectory of additional smoke plumes

• The influence of lingering heat and humidity on pollutant levels

Further forecast updates will provide additional detail as conditions evolve through the end of the week.

07/22/2025 Forecast Update

Pollutant Overview

Ozone (O₃):
8-hour average ozone concentrations are expected to range from Good (Green AQI) to Moderate (Yellow AQI). A small chance for Unhealthy for Sensitive Groups (Orange AQI) exists, particularly in southern areas.

Fine Particulates (PM-2.5):
24-hour average concentrations will be mostly Moderate (Yellow AQI) statewide, with some influence from surface-level smoke.

Forecast Discussion

Two key features are shaping Michigan's weather between Tuesday and Wednesday:

• A high-pressure system positioned east of the state will keep conditions mostly quiet.

• A frontal boundary to the northwest will begin bringing precipitation to the western Upper Peninsula later Tuesday. This front will slowly move south through Thursday, eventually impacting the Lower Peninsula with potential rain and storms.

In the meantime, temperatures will climb into the 80s and 90s, and humidity levels will rise, creating more uncomfortable outdoor conditions as the week progresses.

As for air quality:

• Fine particulate levels (PM2.5) will remain mostly Moderate, as lingering smoke from Wisconsin and Lake Michigan shifts back over the region. No significant spikes are expected.

• Ozone concentrations may also increase slightly due to this smoke, but rising dew points will likely help limit formation. A small chance for USG ozone levels exists in southern Michigan, though Good to Moderate conditions are expected across most areas.

Extended Outlook

Smoke model data suggests another potential smoke intrusion behind the frontal boundary on Thursday, which could impact air quality later in the week.

There remains uncertainty in the extended forecast regarding:

• Timing of precipitation

• Duration of lingering heat

• Potential for wildfire smoke return

Future updates will provide more detail as conditions develop.

07/21/2025 Forecast Update

Pollutant Overview

Ozone (O₃):
8-hour average ozone concentrations are expected to remain Good (Green AQI) to Moderate (Yellow AQI). There is a small chance of Unhealthy for Sensitive Groups (Orange AQI) at select southern Michigan monitors on Tuesday afternoon.

Fine Particulates (PM-2.5):
24-hour average concentrations will be mostly Moderate (Yellow AQI), with improving conditions across southern Michigan as lingering wildfire smoke clears.

Forecast Discussion

Fine particulate concentrations increased across Michigan late Sunday into early Monday due to a north-to-south moving wildfire smoke plume. Hourly PM2.5 levels reached the USG (Orange AQI) range in parts of the southwest, but daily averages remained Moderate across the state.

High pressure will remain in control through Tuesday, bringing plenty of sunshine, comfortable temperatures, and low humidity. Beginning Wednesday, high pressure will shift east as an upper-level ridge (heat dome) builds over the southeastern U.S., bringing hotter, more humid air into Michigan by midweek. A boundary approaching from the north will introduce storm chances beginning Wednesday or Thursday.

For air quality:

• PM2.5 levels are expected to improve on Monday, with Good conditions in northern areas and Moderate in the south. Lingering smoke may lead to continued Moderate levels on Tuesday, but higher concentrations are not expected.

• Ozone levels will range from Good to Moderate, though surface smoke may enhance ozone formation in some areas. A few southern monitors could briefly reach USG (Orange AQI) levels Tuesday afternoon.

We will continue monitoring conditions and will update the forecast if ozone levels appear likely to rise further as heat and humidity build midweek.

Extended Outlook

Uncertainty remains regarding additional wildfire smoke moving into the region with the expected frontal boundary later this week. Forecasts will be updated accordingly as conditions evolve.

07/18/2025 Forecast Update

Pollutant Overview

Ozone (O₃):

8-hour average concentrations are expected to remain Good (Green AQI), with scattered periods of Moderate (Yellow AQI) throughout the forecast period.

Fine Particulates (PM-2.5):
24-hour average concentrations are also expected to be Good (Green AQI) overall, with isolated instances of Moderate (Yellow AQI).

Forecast Discussion

A cooler, drier air mass will settle over Michigan following Thursday’s clouds. Friday will feel refreshing, with highs near 80°F and no wildfire smoke in the region—setting the stage for excellent air quality to begin the weekend.

Saturday brings a chance of thunderstorms and potential severe weather. Morning showers could reduce afternoon storm intensity by limiting instability. However, if the morning stays dry, the likelihood of stronger afternoon storms increases. Regardless, Saturday is likely to be wet.

Sunday will see a return to sunny skies and comfortable temperatures in the low 80s, accompanied by light north-northeast winds. Air quality is expected to remain mostly Good for both ozone and fine particulates.

Looking ahead, summer weather returns midweek, with temperatures possibly reaching the low 90s and continuing into the following weekend.

Extended Outlook

Air quality is not expected to be an issue as the upcoming work week begins.

07/14/2025 Forecast Update

Current Alerts & Advisories

• A Statewide Air Quality Alert remains in effect for Monday, July 14, due to Fine Particulates (PM-2.5).

• An Air Quality Advisory for Ozone is in effect for Tuesday, July 15, in the following Southeast Michigan counties:
  Livingston, Macomb, Monroe, Oakland, St. Clair, Washtenaw, and Wayne.

Pollutant Overview

Ozone (O₃):

• 8-hour average concentrations will range from Good (Green AQI) to Moderate (Yellow AQI) across most of the state.

• Unhealthy for Sensitive Groups (Orange AQI) is expected in Southeast Michigan on Tuesday.

Fine Particulates (PM-2.5):

• Early in the week, levels are expected to be Moderate (Yellow AQI).

• Conditions should improve midweek, with a mix of Good (Green AQI) and Moderate levels expected statewide.

Forecast Discussion

Another episode of elevated wildfire smoke affected Michigan over the weekend, leading to alerts that extend through Monday. The heaviest smoke is now shifting east into Ontario, but Michigan will remain under alert until conditions fully clear. By Tuesday, air quality is expected to improve statewide, though brief morning impacts may still occur in the far western Upper Peninsula.

A separate smoke plume over northern Minnesota is not expected to reach Michigan. No additional wildfire smoke-related issues are forecasted at this time, but conditions will continue to be monitored and updated as necessary.

Tuesday Ozone Advisory

Weather conditions on Tuesday, July 15, will be favorable for ozone formation in Southeast Michigan, including:

• High temperatures near 90°F

• Sunny skies

• Light winds

• Dew points in the mid-60s

These conditions can lead to elevated ozone concentrations, prompting the issuance of an advisory. Sensitive groups should limit prolonged outdoor activity. A change in weather is expected Wednesday afternoon, bringing cloud cover and rain ahead of a cold front, which should end this brief ozone event.

Extended Outlook

A cold front is forecasted to pass through Thursday, bringing:

• Cooler temperatures

• Lower humidity

• Improved air quality

No air quality issues are currently expected for the upcoming weekend.

07/13/2025 Forecast Update

Statewide Air Quality Alert in Effect

A statewide Air Quality Alert has been issued for fine particulate (PM-2.5) due to wildfire smoke from Canada impacting Michigan through Monday.

Pollutant Overview

PM-2.5 (Fine Particulate):

• Upper Peninsula & Northern Lower Michigan: Unhealthy (Red AQI) to USG (Orange AQI)

• Central Michigan: Unhealthy to USG

• Southern Michigan: USG to Moderate (Yellow AQI)

Ozone:

• Generally in the Good to Moderate range statewide

• Scattered USG possible Monday, especially in southern Michigan due to warmer temperatures and light winds

Forecast Details

Wildfire smoke continues to move into Michigan Sunday, spreading south and east throughout the day. Additional smoke plumes are forecast for Monday. Expect elevated fine particulate levels, particularly in northern and central Michigan.

By Monday, a southerly wind shift could increase ozone levels slightly, with the potential for a few areas to reach the USG range in the southern part of the state.

Looking Ahead

Dry and warm conditions are expected to persist into Tuesday. Without a significant airmass change, air quality concerns may continue into midweek.

Next Forecast Update: Monday, July 14, 2025

07/12/2025 Forecast Update

FORECAST SUMMARY: Saturday, July 12, 2025 - Sunday, July 13, 2025

Air Quality Alert for fine particulate begins at noon on Saturday, July 12 for the western Upper Peninsula, expanding statewide on Sunday, July 13 through noon Monday, July 14.

Saturday Alert Counties:
Baraga, Dickinson, Gogebic, Houghton, Iron, Keweenaw, Marquette, Ontonagon

Sunday–Monday Alert:
Statewide

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

PM-2.5:

• Saturday: Daily average fine particulate concentrations expected to range between Very Unhealthy (Purple AQI) to Unhealthy (Red AQI) in the western Upper Peninsula, with levels remaining mostly Moderate elsewhere.

• Sunday: Concentrations will range from Very Unhealthy to Unhealthy in northern Michigan to USG (Orange AQI) and Moderate in southern regions.

FORECAST DISCUSSION:
A cold front will move through the region on Saturday, bringing chances of showers and storms. Behind the front, high pressure will build in on Sunday, ending precipitation from west to east. Warm, dry conditions are expected into the start of the workweek.

The primary air quality concern is elevated PM-2.5 levels from wildfire smoke moving down from Canada. Current smoke models show a concentrated plume entering the western Upper Peninsula by Saturday afternoon, moving across the U.P. and into Lower Michigan from late Saturday through Sunday.

As this occurs, elevated PM-2.5 concentrations are anticipated statewide. Based on model trends:

• Very Unhealthy to Unhealthy levels are expected across the Upper Peninsula and northern Lower Michigan.

• Unhealthy to USG levels in central portions of the state.

• USG to Moderate levels further south.

Forecast updates will continue, with the next one scheduled for Sunday morning, which will also assess whether the air quality alert needs to extend beyond noon on Monday.

Looking ahead, ozone may become a concern into early next week, as southerly winds and warmer conditions return. This will also be reviewed in the next update.

EXTENDED FORECAST:
Dry, warm weather continues into next week. Conditions may support elevated ozone and/or PM-2.5 levels later in the period. Updates will be provided as needed.

Next forecast update: Sunday, July 13, 2025

07/10/2025 Forecast Update

Air Quality Outlook – July 10–12, 2025

As we head into the weekend, air quality remains mostly stable across lower Michigan. Here’s what to expect in the days ahead.

Quick Summary

• Ozone (O₃): Expected to remain in the Good (Green AQI) to Moderate (Yellow AQI) range

• Fine Particulate Matter (PM2.5): Daily averages will fall between upper Good and low Moderate

Weather & Air Quality Breakdown

Thursday (July 10):

• High pressure will bring calm conditions and light winds

• Ozone and PM2.5 levels expected to stay in the Good to low-Moderate range

Friday (July 11):

• A disturbance brings increasing clouds and potential rain

• These conditions will help limit ozone buildup

• Fine particulate levels will hover in the low-Moderate range

Saturday (July 12):

• A warm front moves north, followed by a cold front later in the day

• Precipitation and cloud cover will likely keep ozone in check

• Wildfire smoke from Canada may move into the region by late Saturday—forecasters are monitoring this closely for potential impacts on PM2.5

Extended Outlook

Looking ahead to early next week, forecast models show dry and warm conditions returning. This could lead to rising pollution levels, especially ozone. We’ll continue to monitor for any changes.

Next Update

The next air quality update will be posted on Saturday, July 12, 2025. Check back then for the latest conditions and outlook.

07/07/2025 Forecast Update

Weekly Air Quality Outlook – July 7–10, 2025

Welcome back from the 4th of July holiday! Here’s what to expect this week for air quality across lower Michigan.

Quick Summary

• Ozone: Ranging from Good (Green AQI) to Moderate (Yellow AQI)

• Fine Particulate Matter (PM2.5): Expected to remain between upper Good and Moderate levels

After the Fireworks

Fireworks over the weekend caused short-term spikes in fine particulate levels, with some areas exceeding 150 µg/m³. Thankfully, by July 5th, conditions had already improved, and daily averages returned to Moderate or better.

Weather & Air Quality Breakdown

Monday (July 7):

• Clouds will clear from northwest to southeast

• Some wildfire smoke aloft, but no major ground-level impacts expected

• Cooler northerly flow will help suppress ozone formation

Tuesday-Thursday:

• These are the most likely days to see Moderate ozone levels, especially in southern Michigan

• A midweek disturbance could bring brief showers

Friday:

• As high pressure moves out, southerly winds return

• May lead to a slight uptick in ozone levels — stay tuned for Thursday's update

Extended Forecast

Looking into the weekend, models show rain possible Saturday, which could help keep pollution levels down. Overall, no air quality category is expected to exceed Moderate during this forecast period.

Next Update

We’ll post our next air quality update on Thursday, July 10, 2025. Be sure to check back or follow us on social media for the latest information.

07/04/2025 Forecast Update

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

Ozone:

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

PM-2.5:

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

Air Quality Advisory for Ozone on July 4, 2025, for the following counties:

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

Air Quality Advisory for PM-2.5 on July 4, 2025, for the following counties:

Livingston, Macomb, Monroe, Oakland, St. Clair, Washtenaw, Wayne

FORECAST DISCUSSION:

Two Air Quality Advisories are in place today, July 4th, one in west Michigan along the Lake Michigan shoreline for Ozone, and the other is in metro Detroit for PM-2.5.

The environment over Lake Michigan and along the Lake Michigan shoreline is primed for Ozone development. These conditions will persist tomorrow, Saturday, so the current Air Quality Advisory for Ozone will be extended through Saturday, July 5th. Surface temperatures will increase into the low-to-mid 90s with winds shifting to southwesterly, both near the surface and in the upper-levels. Additionally, upper-level temperatures will be near twenty degrees Celsius, which is ideal for the Ozone photochemical reaction to occur. These conditions will be present over southeast Michigan as well, mixing with a potentially dirty atmosphere, so an Air Quality Advisory for Ozone will be issued for the metro Detroit area tomorrow, Saturday.

For PM-2.5, the current Advisory in place will be extended through Saturday, July 5th. Light winds will continue through today, Friday, and last until early Saturday afternoon when winds are expected to pick up. PM-2.5 concentrations are expected to improve throughout Saturday afternoon as winds pick up.

Come Sunday, a Low-pressure system and associated frontal boundary will cross over the state bringing NNW winds and a chance of rain showers. This will clean out the atmosphere and improve overall air quality through Monday, July 7th.

EXTENDED FORECAST:

Air quality looks Good to start off the next week.

07/03/2025 Forecast Update

FORECAST SUMMARY: Thursday July 3, 2025, through Friday July 4, 2025

Ozone:

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

PM-2.5:

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

Air Quality Advisory for Ozone on July 4, 2025, for the following counties:

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

 FORECAST DISCUSSION:

Holiday travel is in full swing and firework displays are booming across the Great Lakes state. Weather-wise, with the exception of the western Upper Peninsula, one could not ask for a better 4th of July with temperatures well into the 80s, light winds and plenty of sunshine. This is due, in part, to a High-pressure system moving across the region and along the eastern Lake Huron shoreline. Regionally, this pressure system will hang around through Saturday, providing similar weather conditions then as well.

Unfortunately, however, poor air quality is expected as well due to the aforementioned weather set up. For the Lake Michigan shoreline, an Air Quality Advisory for Ozone is in place for Friday July 4 due to light SSW winds, mostly sunny skies and surface temperatures well into the 80s creating a conducive environment for Ozone development. There is a chance of clouds in the early to mid-afternoon but due to the proper ingredients in place, along with firework displays adding more ingredients for Ozone to develop in the atmosphere, USG-level Ozone should be expected. Although this forecast will be updated Friday morning, it can be expected to see USG-level Ozone along the Lake Michigan shoreline on Saturday as well.

06/30/2025 Forecast Update

FORECAST SUMMARY: Monday June 30, 2025, Thursday July 3, 2025

Ozone:

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

PM-2.5:

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

FORECAST DISCUSSION:

Summer is in full swing as we round off the month of June and enter July this week. Today, Monday, will see hot temperatures return along with high dewpoint temperatures which will increase humidity across the state. The mixture of hot temperatures, humid air, and an impending cold front will cause popup rain showers and potential storms throughout the day today. Once the cold front moves off to the southeast overnight, Tuesday will be slightly cooler in the upper-70s to low-80s, and drier air with dewpoints in the low-50s. This trend continues into Wednesday as a High-pressure moves in throughout the day and is expected to hang around to start off the holiday weekend.

With the exception of Tuesday, winds throughout this week will be from the WSW, which may pose a threat of increases in Ozone, but for the time being, there appears to be no threat of widespread USG-level Ozone for multiple hours due to the aforementioned cold front cleaning out the atmosphere later Monday into Tuesday. Also, the cooler temperatures on Tuesday and into Wednesday will help keep Ozone concentrations at bay. Concentrations may approach the USG range, but nothing to cause an Advisory to be issued. For PM-2.5, there appears to be regional wildfire smoke across the Midwest this week which may increase PM-2.5 concentrations, but nothing more than mid-to-high Moderate at the worst. PM-2.5 concentrations may also see an increase throughout this week and into the weekend due to 4th of July festivities, especially fireworks. This forecast will be updated on Thursday to get a better look at conditions for the holiday weekend ahead.

EXTENDED FORECAST:

Hot temperatures return for the holiday weekend along with sunshine and a chance for rain on Saturday. Expected air quality will be forecasted on Thursday for the weekend ahead, but general Moderate conditions can be expected at this time, with a chance at hourly USG concentrations.

Next Forecast update: Thursday July 3, 2025

06/27/2025 Forecast Update

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

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

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

FORECAST DISCUSSION

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

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

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

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

  EXTENDED FORECAST:

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

06/23/2025 Forecast Update

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

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

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

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

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

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

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

  FORECAST DISCUSSION

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

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

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

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

  EXTENDED FORECAST:

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

Next forecast update: Friday, June 27, 2025

06/22/2025 Forecast Update

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

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

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

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

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

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

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

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

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

FORECAST DISCUSSION:

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

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

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

EXTENDED FORECAST:

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

 Next Forecast update: Monday, June 23, 2025

06/21/2025 Forecast Update

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

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

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

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

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

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

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

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

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

FORECAST DISCUSSION:

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

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

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

 EXTENDED FORECAST:

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

 Next Forecast update: Sunday, June 22, 2025

06/20/2025 Forecast Update

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

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

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

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

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

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

 FORECAST DISCUSSION:

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

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

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

 EXTENDED FORECAST:

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

 Next Forecast update: Saturday, June 21, 2025

06/16/2025 Forecast Update

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

Air Quality Advisory for Tuesday, June 17, 2025

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

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

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

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

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

FORECAST DISCUSSION

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

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

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

  EXTENDED FORECAST:

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

06/10/2025 Forecast Update

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

Ozone:

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

PM-2.5:

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

Air Quality Advisory for Wednesday June 11, 2025

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

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

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

FORECAST DISCUSSION:

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

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

EXTENDED FORECAST:

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

Next Forecast update: Wednesday June 11, 2025