10/18/2024 Forecast Update

FORECAST SUMMARY: Friday October 18th, 2024 through Monday October 21st

OZONE:

8-hour average Ozone concentrations are expected to be Good through the forecast period.

 PM-2.5:

24-hour daily average Fine Particulate concentrations will average between Good and Low-Moderate.

FORECAST DISCUSSION:

After a rather Fall-like week, surface temperatures increase throughout this upcoming weekend with the 70-degree mark making its return throughout the state. High-pressure is set up just to our southeast which is bringing warmer air via southwesterly flow. Starting with today, Friday, each of the next two or three days are essentially copy and paste of one another with clear skies, plenty of sunshine and above average temperatures. Due to the High-pressure to our south, winds will be rather light as well, so PM-2.5 concentrations may increase into the upper Moderate range in the morning hours but will slowly dissipate throughout each day. Ozone will continue to be a non-issue as we round out the middle of October and count down the days to the end of the 2024 Ozone season.

There appears to be a plume of upper-level wildfire smoke that will hang around the Great Lakes region throughout this weekend. The aforementioned High-pressure will bring the smoke towards the Great Lakes and the smoke will then rotate around the High-pressure interfering with our blue skies. None of the smoke is expected to reach the surface but will, however, gray out some skies and provide colorful sunrises and sunsets.

 EXTENDED FORECAST:

The 70-degree temperatures continue into the next week until Wednesday when a Low-pressure and cold front enters the region. Overall air quality will remain in the Good range.

Next Forecast Update: Monday, October 21st, 2024

10/14/2024 Forecast Update

FORECAST SUMMARY: Monday October 14th through Friday October 18th, 2024

OZONE:

8-hour average Ozone concentrations are expected to be Good through the forecast period.

 PM-2.5:

24-hour daily average Fine Particulate concentrations will average between Good and Low-Moderate.

FORECAST DISCUSSION:

The chill of Fall has slowly set in the past week or so with a further decrease in temperatures expected this week, but some slight increases as we approach the weekend.

Much needed rain fell across the state this past weekend with some residual showers early this morning. The remnants of the cold front and associated rain that came through will completely move out of the area later today, with northerly winds and cooler temperatures filling in behind it. There is a chance of pop-up lake effect rain showers in the beginning half of this week, but the majority of Michigan will remain dry and in the upper-40s to mid-50s temperature range. As we get into Wednesday, winds shift to a more southwesterly direction, which will cut off any remaining lake-effect rain showers while also increasing surface temperatures across the state. Into Thursday, High-pressure sets up to our east and will stay there into the weekend, providing us warmer temperatures and clear skies.

For air quality, Ozone will be in the Good range as we enter the middle of October and nearing the end of the annual Ozone season. This past weekend saw light, elevated wildfire smoke with some of it still hanging around this Monday morning, Throughout the beginning part of this week, this residual smoke will move out of the region with clear skies moving in behind it. There are still fires burning in west Canada and western US states, but smoke associated with those fires are not expected to impact our upper-levels or surface PM-2.5 concentrations as Good to low-Moderate concentrations are expected.

 EXTENDED FORECAST:

The upcoming weekend looks to be yet another picturesque Michigan Fall weekend with sunny skies and temperatures in the 60s and 70s.

Next Forecast Update: Friday October 18th, 2024

10/11/2024 Forecast Update

FORECAST SUMMARY: Friday, October 11, 2024, through, Monday October 14, 2024

OZONE:

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

 PM-2.5:

24-hour daily average Fine Particulate concentrations will average between Good and Moderate (Yellow AQI).

FORECAST DISCUSSION:

We expect breeze conditions today, Friday, as a frontal boundary approaches from the northwest and high pressure departs to our east. The gusty southwest wind flow between these systems, along with dry conditions, will make an environment more prone to fire development. The National Weather Service has either Red Flag Warnings or Fire Weather Watches in place today across the northern half of the lower peninsula to highlight this risk.
The cold front passes through the state Friday, then stalls across northern Indiana and Ohio this weekend. A small chance for precipitation exists as the boundary passes Friday, but a better chance for rain comes in the forecast for later Saturday into Sunday as a disturbance travels along the boundary just south of the state. High temperatures on Friday will be above normal, generally in the 70s, but readings decrease behind the cold front, with temperatures during the weekend falling from the 50s north to the 60s south.

 As for air quality, warmer temperatures are in place Friday with a southwest flow, but being so late in the ozone season, we expect readings to remain in the Good range through the forecast period. Similar to this past Sunday, the cold front passing through the state on Friday looks to bring in some smoke from fires far to the north and west of the region. This will likely cause increases in hourly fine particulate concentrations, but it does not look like higher readings would last for a long time. While hourly concentration may reach into the upper Moderate range, we do not anticipate daily averages of fine particulate to reach higher than the low to middle Moderate range. After the frontal passage, fine particulate may continue in the Moderate range across the south, closer to the stalled boundary, with Good concentrations expected across the rest of the state. The late Saturday into Sunday system should help keep fine particulate from developing, and readings are expected to average mostly Good.

 We will keep an eye on conditions during the weekend, and if conditions change from what is currently expected, this forecast will be updated to reflect the change.

 EXTENDED FORECAST:

Extended forecast models show cooler temperatures with chances for precipitation continuing into early next week. Air quality in the long term should not be any higher than low-Moderate.

Next Forecast Update: Monday, October 14, 2024

10/07/2024 Forecast Update

FORECAST SUMMARY: Monday, October 7, 2024, through Friday, October 11, 2024

OZONE:

Ozone concentrations will be Good .

 PM-2.5:

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

FORECAST DISCUSSION:

Unexpected hourly increases in PM2.5 concentrations were seen across the state on Sunday. These increases were caused by upper-level wildfire smoke being brought down to the surface behind a cold front that passed through. All monitors experienced hourly increases, with most locations reaching into the upper Moderate range; however, the increases only lasted a few hours, and daily averages remained low-Moderate. The highest increases in hourly concentrations were seen at our Grand Rapids area monitors, where readings reached the Unhealthy for Sensitive Groups (USG-Orange AQI) for a couple of hours. Like other areas, the increases were partly due to the upper-level smoke being transported to the ground, but more so they were influenced by area fires that developed in Ottawa County. The plumes from those fires were pushed east, towards the monitors. Those fires were put out during the day, with the increased PM2.5 concentrations only lasting a few hours.

 For this week, Canadian high pressure sinking in will produce cooler fall-like conditions. A shortwave passing by northern locations early this week may kick off light precipitation; otherwise, dry conditions prevail under a northwesterly wind flow. By Friday, the high-pressure area weakens and moves east, allowing winds to turn more southerly. High temperatures this week will primarily be in the 60s, increasing towards 70 late in the week. Cool nighttime temperatures in the 30s to 40s can be expected, along with areas of frost some mornings.

 Air quality conditions during the week are expected to average mostly Good, aside from a low-Moderate daily PM2.5 concentration mixing in. During the week, we will keep an eye on weather conditions along with any changes in expected smoke transport and/or local fire development that may occur. Updates will be made to this forecast if conditions change from what we currently expect.

 EXTENDED FORECAST:

Extended forecast models show a boundary moving in from the north that may bring in a small chance for precipitation. Air quality in the long term should not be any higher than low-Moderate.

Next Forecast Update: Friday, October 11, 2024

10/04/2024 Forecast Update

FORECAST SUMMARY: Friday October 4th, through Monday October 7th, 2024

OZONE:

Ozone concentrations will be Good .

 PM-2.5:

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

FORECAST DISCUSSION:

As Fall colors start to pop and temperatures slowly begin to cool, we enter the first weekend of October with a few sprinkles across the state, but clear skies later into today and tomorrow, Saturday. The remnants of a cold front that passed over us last night has a few rain showers and clouds hanging around. As stated prior though, clear skies will dominate the region this afternoon as a High-pressure system moves in just in time to kick off the weekend. Saturday will be a picturesque Fall day with warmer than normal temperatures well into the 70s for most areas across the state. Just as quickly as the High-pressure moves in is just as quickly as it leaves due to a Low-pressure system and associated cold front moving in late Saturday night into early Sunday morning. Northerly areas across Michigan will see more rain due to this cold front as southerly areas may see a few spotty showers, but nowhere is expected a complete washout. The cold front moves out as we approach noon on Sunday and some areas will be greeted by the sun come Sunday afternoon. Monday will see a continuation a clear skies but cooler temperatures near our normal highs as we start the first full week of October.

For air quality, Ozone will continue to be a non-issue as temperatures start to cool off more and sunlight becomes less intense. PM-2.5 concentrations will hover around the low-Moderate range for the more populated areas, especially in the morning time as wind is lighter. Any residual build up will surely be cleaned out early Sunday morning as the cold front passes. In the upper levels of the atmosphere, there appears to be a light plume of wildfire smoke which will be over Michigan tomorrow and into Sunday. The smoke will stay in the upper atmosphere but may cause milky skies and colorful sunrises and sunsets.

 EXTENDED FORECAST:

High-pressure looks to sit over the Midwest to start off next week which will help keep the overall air quality Good.

Next Forecast Update: Monday, October 7th, 2024

09/30/2024 Forecast Update

FORECAST SUMMARY: Monday September 30th, through Friday October 4th, 2024

OZONE:

Ozone concentrations will be Good .

 PM-2.5:

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

FORECAST DISCUSSION:

Most of us Michiganders woke up to sun this morning while others woke up to overcast skies and fog. Central Michigan and northward are sitting under clear skies whereas southern Michigan has a persistent cloud deck which is expected to dissipate as the day carries on. Much alike last week, we’ll see both similar surface temperatures, although slightly cooler, and partly cloudy to sunny skies for most of the week. There appears to be two days with rain chances with the first being tomorrow, Tuesday as a cold front moves through the Great Lakes region. The rain showers will be rather widespread and nothing too alarming in terms of amount of rain. Once the cold front moves out, Wednesday and Thursday will see clear skies thanks to a High-pressure system setting up to our south. Come Friday, however, will see the same High-pressure move towards the southeast which will open the door for a Low-pressure system, associated cold front, and chances for rain. This system may pose higher amounts of rain compared to Tuesday, but not a complete washout as the rain will begin to taper off in the Friday evening timeframe.

For air quality, as we round out September and start October this week, we enter the last month of the designated Ozone season with Good Ozone concentrations expected. Temperatures will barely reach the mid-70s this week, which is nice for a slightly above-normal high temperature and keeping Ozone at bay. For PM-2.5, early morning commute hours may pose some hourly Moderate concentrations, but overall daily average should remain in the Good to low-Moderate range. There looks to be a chance of upper-level smoke entering the region midweek but will stay in the upper atmosphere and may create some milky skies and colorful sunrises and sunsets.

 EXTENDED FORECAST:

Once the Low-pressure and cold front move out of the region Friday, a High-pressure sets up for next week providing clear skies for the first weekend of October.

Next Forecast Update: Friday, October 4th, 2024

09/27/2024 Forecast Update

FORECAST SUMMARY: Friday, September 27, 2024, through Monday, September 30, 2024

OZONE:

Ozone concentrations will be Good (AQI Green)..

 PM-2.5:

PM-2.5 concentrations are also expected to be mostly Good (AQI Green).

FORECAST DISCUSSION:

Friday is expected to stay mostly dry under high pressure with continued Good Air Quality.  However, as the remnants of Hurricane Helene travel northwards and begin squeezing that high pressure ridge, winds will increase with some significant wind gusts.

An upper level low over Tennessee will merge with the remnants of Hurricane Helene.   That will send moisture into southern Lower Michigan, tonight, and should be enough to generate light showers throughout the weekend.

High pressure will attempt to build back in Sunday night into Monday, ahead of a cold front on track to move through on Tuesday.

During this time, Air Quality is expected to remain Good, throughout the state.

 EXTENDED FORECAST:

Air Quality is expected to remain Good going into the upcoming work week.

Next Forecast Update: Monday, September 30, 2024

09/23/2024 Forecast Update

FORECAST SUMMARY: Monday, September 23, 2024, through Friday, September 27, 2024

OZONE:

Ozone concentrations will be Good (AQI Green)..

 PM-2.5:

PM-2.5 concentrations are also expected to be mostly Good (AQI Green).

FORECAST DISCUSSION:

After a spell of warm, dry weather, the surface low that brought welcomed rain to the area is now over the eastern Great Lakes.  While dry weather is anticipated on Monday, a surface low lifts in from the southern Mississippi River Valley, tonight, bringing in showers and thunderstorms by early Tuesday and will lingers most of the day.  Air Quality is expected to be Good.

 I anticipate a drying out during Wednesday with high pressure ridging building into the Midwest that will produce dry and sunny conditions through Friday.  Above normal temperatures in the mid to upper 70’s are anticipated with dewpoints in the 50’s making for comfortable conditions.  Air Quality should remain Good.

 Plenty of uncertainty with the upcoming weekend.  Models are showing a sizable tropical storm in the Gulf moving north toward the Florida panhandle.  That could eventually get caught up with the circulation of an upper lever low in the Arkansas/Texas area that is forecast to slowly meander towards the Great Lakes area.  That could encourage what is left of the weakening tropical system to merge and move north through the Tennessee and Ohio Valleys.  Models are currently keeping precipitation well to our south but changes in the tracking could produce some shower activity in Michigan.

 EXTENDED FORECAST:

Air Quality is expected to remain Good going into the upcoming weekend.

Next Forecast Update: Friday, September 27th, 2024

09/20/2024 Forecast Update

FORECAST SUMMARY: Friday, September 20, 2024, through Monday, September 23, 2024

OZONE:

Ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI).

 PM-2.5:

PM-2.5 concentrations will average between Good and Moderate.

FORECAST DISCUSSION:

Two boundaries, one passing through Friday and the other Sunday, bring some much-needed precipitation into the forecast. There is not much of a temperature decrease behind the Friday front, and dry conditions return for Saturday; however, conditions will feel a bit muggier than earlier in the week. On Sunday, the second boundary passing through brings in more widespread precipitation chances. Temperatures through the weekend continue trending above normal.

 Since Monday levels of ozone and fine particulate have generally ranged from Good to Moderate, aside from yesterday when three western monitors climbed just over the Unhealthy for Sensitive Groups (USG) range for ozone. On Friday, clouds associated with the frontal boundary should hamper ozone development, keeping readings ranging from Good to Moderate through the state. Dry, sunny conditions on Saturday will likely allow for ozone increases into the Moderate range over much of the state, but more cloud cover and precipitation by Sunday afternoon should bring readings into the Good to low-Moderate range. Without a significant airmass change expected through the weekend, daily averages of fine particulate will continue to range from Good to low Moderate.

 EXTENDED FORECAST:

Extended forecast models show rain chances lingering into early next week, with high temperatures becoming closer to normal for this time of year. Air quality should range generally Good early next week.

Next Forecast Update: Monday, September 23th, 2024

09/16/2024 Forecast Update

FORECAST SUMMARY: Monday, September 16, 2024, through Friday, September 20, 2024

OZONE:

Ozone concentrations are expected to range between Good (Green AQI) and Moderate (Yellow AQI).

 PM-2.5:

PM-2.5 concentrations will average between Good and Moderate.

FORECAST DISCUSSION:

The weather conditions this week will primarily be a repeat of last week across Michigan. The forecast features unseasonably warm “summer-like” temperatures and generally dry conditions. With high pressure settled to our east most of the week, a continued east/southeasterly wind flow should keep pollution levels from increasing much over the region. Also to note is that wildfire smoke is present at upper levels through at least mid-week; however, ground-level impacts are not anticipated. Levels of both pollutants should remain steady in the upper Good to middle Moderate range through the period.

 As mentioned, the “summer-like” conditions continue this week, but an increase in cloud cover may be noticed later in the period, along with a slight decrease in high temperatures. This change in conditions will depend on the track of a storm system that is forecast to come onshore over the Carolinas today (Monday). The most recent forecast guidance keeps this storm system south and east of the region after it comes inland.

 AQD meteorologists will keep an eye on the weather and air quality conditions through the week, and this forecast will be updated if the current forecast trend changes, and we expect increases in pollution levels from the current upper Good to middle Moderate forecast.

 EXTENDED FORECAST:

Extended forecast models show the warm, dry conditions continuing, along with the general trend of Moderate pollution levels.

Next Forecast Update: Friday, September 20th, 2024

09/06/2024 Forecast Update

FORECAST SUMMARY: Friday, September 6, 2024, through Monday, September 9, 2024

OZONE:

8-Hour average Ozone concentrations will be Good (AQI Green).

 PM-2.5:

24-hour average Fine Particulate concentrations are also expected to be mostly Good (AQI Green).

FORECAST DISCUSSION:

Following the passage of a Thursday night cold front, the warmer temperatures of the past few days will be replaced with cooler, dry Canadian air.  Weekend temperatures will reach the high 60’s with dry dew points in 40’s.  Air Quality will be Good through the weekend.

Summer is not entirely gone, though.  By Monday, temperatures will rebound into the upper 70’s and by Tuesday, back into the 80’s.  Most of the second half of the week will experience temperatures in the upper 80’s.  While the chances of elevated ozone decrease as autumn nears, under the right conditions, it can still occur.  As such, we will be keeping an eye on potential developments as the week progresses.

 Wildfires continue in the western states and provinces.  All smoke models agree that we should not see any impact at ground level.

 EXTENDED FORECAST:

Air Quality is expected to remain Good going into the upcoming work week.

Next Forecast Update: Monday, September 9, 2024

09/03/2024 Forecast Update

FORECAST SUMMARY: Tuesday, September 3, 2024, through Friday, September 6, 2024

OZONE:

8-Hour average Ozone concentrations will be Good (AQI Green) increasing to Moderate (AQI Yellow).

 PM-2.5:

24-hour average Fine Particulate concentrations are expected to be mostly Good (AQI Green).

FORECAST DISCUSSION:

High pressure continues to slide overhead.  This will keep our daytime weather summer-like warm and dry through Thursday.  Chilly overnight temperatures, under clear skies, will also occur but will warm quickly during the first few hours of daylight underneath sunny skies.  Afternoon high temperatures will increase, each day, climbing to the mid-80’s by Thursday as warm air advection keeps pumping in warmer air.

Air Quality from potential ozone development will range from Good, early in the week, to Moderate as the week progresses.  Thursday will be the peak for the warming trend and Air Quality will likely degrade to the high Moderate range, by that time.  But I am not seeing enough evidence to support any thoughts of an advisory at this point.  I will be checking, however, and upgrade the Thursday forecast, if necessary.

 A strong cold front will pass through the state early Friday morning.  Pretty high confidence that daytime highs, during the weekend, will be down into 60’s with morning lows in the 40’s.   Rain chances continue into Saturday with decreasing chances by Sunday.  Air Quality will be Good following the passage of the cold front.

 Wildfires continue in the western states and provinces.  All smoke models agree that we should not see any impact at ground level although smoke high in the atmosphere is a possibility.

 EXTENDED FORECAST:

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

Next Forecast Update: Friday, September 6, 2024

08/30/2024 Forecast Update

FORECAST SUMMARY: Friday, August 30, 2024, through Tuesday, September 3, 2024

OZONE:

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

 PM-2.5:

24-hour daily average Fine Particulate concentrations will average between Good and Moderate (Yellow AQI).

FORECAST DISCUSSION:

As we move into the Labor Holiday weekend, weather conditions will feature two frontal boundaries. The first boundary passes through Friday, and chances for showers and storms come into play as it moves through. Weather conditions dry out for Saturday, and temperatures in the 80s are expected. The second boundary may bring precipitation to the northern portions of Michigan, but the rest of the state should remain dry. What will be most noticeable with this front will be the cooler temperatures moving into the region. Weather conditions Sunday through the Labor Day holiday will be dry, with highs generally in the 70s.

 Ozone concentrations may continue in the Moderate range in southern portions of the state Friday and Saturday; however, cooler temperatures on a northerly wind will allow for Good concentrations the rest of the forecast period.

 As for fine particulate, concentrations Friday and Saturday should continue in the upper Good and low Moderate ranges. An airmass change with air from Canada usually produces low pollution levels, but smoke models are showing wildfire smoke sinking into the region behind the Sunday boundary. At this time, northern portions of the state may see increases in fine particulate early next week; however, only minor ground-level influence is expected, and any increases should only be into the low to middle Moderate range. We expect fine particulate concentrations through the Labor Day holiday to reach no higher than middle Moderate; however, we will be keeping an eye on conditions, and we will update this forecast if readings higher than Moderate become a possibility.

EXTENDED FORECAST:

Extended forecast models show cooler and dry conditions into mid-week next week. Air quality should continue to range between Good and Moderate.

Next Forecast Update: Tuesday, September 3, 2024

08/26/2024 Forecast Update

FORECAST SUMMARY: monday, august 26, 2024 through Friday, August 30, 2024

OZONE:

8-hour average Ozone concentrations are expected to range mostly Moderate (Yellow AQI) on Monday, but levels Tuesday could reach the Unhealthy for Sensitive Groups (USG, Orange AQI) range in parts of southwest Michigan. Reading Wednesday and the rest of the week should range between Moderate and Good (Green AQI).

 PM-2.5:

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

FORECAST DISCUSSION:

Warm, muggy conditions start this week with storms that will be scattered in nature on Monday. On Tuesday, precipitation will be more prevalent across the middle and central portions of the state during the morning and early afternoon hours. More sunshine is expected further south, especially in the southwest portion of the state. The sunshine, coupled with warm, muggy conditions and a southwest-to-westerly flow, will assist in the development of ozone. With the increased threat of ozone development, we have decided to issue an Air Quality Advisory from Muskegon to Grand Rapids, then south to the state border. There is a small chance a monitor may reach the USG range in the southeast as well but based on the evaluation of weather models on Monday morning, more cloud cover should help keep readings from reaching higher than the Moderate range.

There is some uncertainty about the placement of a frontal boundary moving in on Wednesday. Currently, it looks to stall over the region for a day, and more clouds and chances for precipitation by mid-week should hamper ozone from reaching higher than Moderate. If our thoughts on the expected pollution levels change, we will update this forecast. Ozone concentrations from Wednesday through Friday should range from the upper Good to the middle Moderate range.

 The current weather setup has also been keeping PM2.5 levels mostly Moderate across the state. Levels will continue to range generally Moderate until we have a good change in airmass, which likely won’t come until the end of the week.

EXTENDED FORECAST:

Extended forecast models show cooler conditions as we approach the coming Labor Day weekend. At this time, increased pollution levels are not anticipated.

Next Forecast Update: Friday, August 30, 2024

08/23/2024 Forecast Update

FORECAST SUMMARY: Friday, August 23, 2024, through monday august 26

OZONE:

8-hour average Ozone concentrations are expected to range mostly Good (Green AQI) through Thursday, then levels could increase towards Moderate (Yellow AQI).

PM-2.5:

24-hour daily average Fine Particulate concentrations will average mostly Good.

FORECAST DISCUSSION:

After a week full of Fall-like temperatures, we end the work week with a slight increase in temperatures as we’re at the cusp of a return to Summer-like normal temperatures. The High-pressure system that has been providing us this Pure Michigan weather will be moving off to the southeast throughout today and tomorrow. This will give way for warmer temperatures to move in as we go through this weekend due to wind direction shifting to more southerly flow. As we approach Sunday, temperatures are expected to reach into the mid-80s with Monday seeing a return to the upper 80s and even the 90s in some areas. With this heat, humidity is expected to increase as well due to winds bringing in both warmer temperatures and moisture. We kick off next week with heat indices well into the 90s with upper-90s in more southern areas. For air quality, PM-2.5 concentrations look to remain in the Moderate range due to lingering wildfire smoke from out west, which is mainly staying in the upper atmosphere. This week, a mulch fire broke out in Detroit which caused numerous mornings to have occasional USG-level PM-2.5 concentrations. Luckily, though, those concentrations only lasted for an hour or so and quickly dissipated as mornings carried on. For the beginning half of the weekend, Ozone does not look to be a threat due to unfavorable winds and slightly cooler temperature compared to how we end the weekend. As temperatures increase as we get into Sunday, Ozone concentrations can be expected to ramp up and increase throughout the day with Monday seeing a rather favorable environment for Ozone development. We will be taking a look at Monday throughout this weekend and will make changes to the forecast if concentrations warrant it.

EXTENDED FORECAST:

As mentioned above, Summer looks to return for the beginning part of next week, with midweek and beyond cooling down after a Low-pressure and cold front roll through on Tuesday into Wednesday. Air Quality should remain in the Good to Moderate range.

Next Forecast Update: Monday, August 26, 2024

08/19/2024 Forecast Update

FORECAST SUMMARY: Monday, August 19, 2024, through Friday, August 23, 2024

OZONE:

8-hour average Ozone concentrations are expected to range mostly Good (Green AQI) through Thursday, then levels could increase towards Moderate (Yellow AQI).

PM-2.5:

24-hour daily average Fine Particulate concentrations will average mostly Good.

FORECAST DISCUSSION:

Wildfire smoke moved into the state this past weekend; however, impacts at the surface have not resulted in hourly concentrations of PM2.5 higher than the low to middle Moderate range, and daily averages have ranged from upper Good to low Moderate. High pressure builds in over the next few days producing winds from the north to northeast. This flow will push the smoke south and west of the region, and Good PM2.5 concentrations should return to the state on Monday, continuing through midweek.

 This week, the high-pressure area dominates, bringing in cooler air from Canada. Plenty of sunshine is anticipated, but cooler surface and upper-level temperatures will hamper any ozone development. Ozone concentrations through Thursday should remain in the Good range. Southerly winds move back over the state by Friday as the high pressure tracks east of the state. This southerly flow brings in warmer air, along with the threat of increases in pollution levels. Either ozone and/or PM2.5 may increase back towards the Moderate range on Friday, but the threat of higher levels should hold off until the weekend.

EXTENDED FORECAST:

Extended forecast models show a warmup towards the end of the week with dry conditions. Increases in pollution levels may be experienced during the coming weekend. Expected pollution levels during the coming weekend will be detailed in the Friday update.

Next Forecast Update: Friday, August 23, 2024

08/16/2024 Forecast Update

FORECAST SUMMARY: Friday, August 16, 2024, through Monday, August 19, 2024

OZONE:

8-Hour average Ozone concentrations will be mostly Good (AQI Green).

PM-2.5:

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

FORECAST DISCUSSION:

Low pressure over northwest WI and an upper low is sending minor short waves of low pressure eastward towards Michigan.  That will keep the weekend mostly wet and cool. 

The rain should end Sunday evening as the low pressure systems migrates eastward.  Clearer weather is expected, early next week, with unseasonably cooler weather as northwest winds bring in cooler air.

 Ozone concentrations will certainly be Good during this time period.  However, we are keeping a close eye on wildfire smoke out west as the models are showing Minnesota and Wisconsin potentially receiving some surface smoke.  The models are also indicating some surface smoke may reach Michigan, later in the weekend, but concentrations only reaching the Moderate range. While I do not anticipate anything worse than Moderate, we will keep a close eye on the situation and update this forecast should anything change.

EXTENDED FORECAST:

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

Next Forecast Update: Monday, August 19, 2024

08/12/2024 Forecast Update

FORECAST SUMMARY: Monday, August 12, 2024, through Fri, August 16, 2024

OZONE:

8-Hour average Ozone concentrations will be mostly Good (AQI Green) to Low Moderate (AQI Yellow).

PM-2.5:

24-hour average Fine Particulate concentrations are also expected to be mostly Good (AQI Green).

FORECAST DISCUSSION:

If you did not get out and enjoy the weather during the past weekend, you missed a golden opportunity.  The good news is that the same weather pattern will persist for the next few days.

 Monday skies will remain partly sunny, and it will be a little milder with high temperatures reaching the upper 70s to lower 80s.  While the forecast is showing the slight possibility for some pop-up type of showers, during Monday afternoon, the dry conditions make that a remote possibility.  Similar conditions look to persist through Wednesday and into Thursday with a gradual increase in temperature into the mid-80’s.  Air Quality should remain mostly Good during this period with the possibility of Low Moderate in Southeast Michigan during Wednesday.

 There is increasing confidence for a widespread and substantial rainfall event occurring on Thursday night and Friday.  Models are indicating amounts ranging for 0.5” to 2.0” of potential rain through the area.  Low pressure looks to persist through the weekend with clouds, scattered showers, and daytime high temperatures in the upper 70’s.  Air Quality should remain mostly Good during this period.

EXTENDED FORECAST:

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

Next Forecast Update: Friday, August 16, 2024

08/09/2024 Forecast Update

FORECAST SUMMARY: Friday, August 9, 2024, through MonDAY, August 12, 2024

OZONE:

8-Hour average Ozone concentrations will be mostly Good (AQI Green).

PM-2.5:

24-hour average Fine Particulate concentrations are also expected to be mostly Good (AQI Green).

FORECAST DISCUSSION:

It is a rare thing, in Michigan, to look at the long-range forecast and see mostly clear skies throughout the forecast.  Add cool, pleasant temperatures and low humidity and the next few days will be ideal.  The only hitch will be breezy conditions following a Friday cold front.  This will bring about sustained westerly winds ranging between 10-15 mph and gusts reaching up between 20 and 25 mph throughout the weekend. 

As the colder winds sweep across Lake Michigan, however, there is a chance of lake induced instability which could throw up a few clouds and random, isolated showers.  These isolated showers would likely be limited to late Saturday and occur closest to the Lake.

Air Quality will be Good throughout the weekend and into the upcoming work week.

EXTENDED FORECAST:

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

Next Forecast Update: Monday, August 12, 2024

08/05/2024 Forecast Update

FORECAST SUMMARY: Monday, August 5, 2024, through Friday, August 9, 2024

OZONE:

8-Hour average Ozone concentrations will be mostly Good (AQI Green).

PM-2.5:

24-hour average Fine Particulate concentrations are expected to be mostly Moderate (AQI Yellow), early in the week, transitioning to Good (AQI Green) for the latter half of the week

Monday and Tuesday look to be the most active weather for the week, followed by cooler, drier weather for the remain of the week and weekend.  As of Monday morning, a cold front is draped across the southern portion of the state and will gradually drop south during the day.  A moisture rich atmosphere will provide the opportunity for locally heavy rainfall amounts along the frontal boundary during Monday.

 More widespread rainfall is likely for late tonight into Tuesday as the front stalls below the Michigan/Indiana/Ohio border.   A wave of low pressure is projected to ride along the boundary and into the Michigan area early Tuesday morning.  Severe weather looks unlikely, but we could see rainfall amounts in the 1”-3” range before it exits the region late Tuesday.

 Any threat of elevated ozone is non-existent during this period.  PM-2.5 values have been hovering in the Moderate range thanks to a small amount of elevated wildfire smoke mixing down from above but will gradually clear out.

 Surface high pressure will dominate our weather for most of the time Tuesday night through Sunday.  This will provide cooler temperatures and drier humidity along with clear skies.  Daytime high temperatures will struggle to get past the 80-degree mark and nights will be comfortably cool with temperatures in the upper 50’s.  Air Quality is expected to be Good for that portion of the forecast period and into the weekend.

 EXTENDED FORECAST:

Air Quality is expected to be Good going into the upcoming weekend.

Next Forecast update: Friday August 9th 2024