12/11/2023 Forecast Update

FORECAST SUMMARY: Monday December 11th, 2023, through Friday December 15th, 2023

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

FORECAST DISCUSSION: As we approach mid-December, surface temperatures hang around seasonal norms with the latest outlook for the remainder of the month showing above normal temperatures. Along with warmer-than-normal temperatures, Michigan is expected to be relatively drier as well.

Today, Monday, will see a continuation of how the weekend ended with surface temperatures ranging from the low to upper 30s. It’ll be breezy throughout the day with winds staying rather consistent throughout the day. Tomorrow is more of the same with an impending weak cold front expected to traverse Michigan Tuesday into Wednesday. Although there will be a cold frontal passage, temperatures stay the same and actually increase as we approach the latter half of the week. If anything, the cold front opens the door for a High-pressure system to set up just to our south on the Indiana/Ohio border. This will provide sunshine for the latter half of the work week which will carry into the weekend.

For air quality, the beginning half of the week will see Good PM-2.5 concentrations, especially with the steady breezy conditions. As we get closer to the weekend, expect PM-2.5 concentrations to get into the Moderate range due warmer surface temperatures and light winds. Surface-level inversions can be expected essentially all week, and the aforementioned Moderate conditions should be expected throughout the week, but more so towards and into the weekend.

EXTENDED FORECAST:

As stated above, a warming trend continues into the weekend which will provide unseasonably warm temperatures and a good amount of sunshine.

Next Forecast Update: Friday, December 15, 2023

12/8/2023 Forecast Update

FORECAST SUMMARY: Friday, December 8, 2023, through Monday, December 11, 2023

PM-2.5:   24-hour average Fine Particulate concentrations are also expected to be Good to Low Moderate transitioning to all Good.

FORECAST DISCUSSION: As of Friday morning, Michigan is in the warm air sector of an approaching frontal system.  We can expect to see temperatures reach as high as the mid-50’s during Friday and early Saturday.  With the warmer temperatures and additional moisture, we are seeing fine particulate concentrations range from Good to Low Moderate throughout the state.

The aforementioned frontal system is expected to pass during the early afternoon hours of Saturday.  Temperatures will begin dropping and by Sunday, high temperatures will only reach the high 30’s.  With the warmer lake waters, it would not be surprising to see some lake effect showers on the west side of the state.  After the front passes and for the rest of the weekend, we can expect GoodAir Quality,

EXTENDED FORECAST:

Air Quality should be generally Good to Low Moderate entering the weekend, then Good.

Next Forecast Update: Monday, December 11, 2023

12/4/2023 Forecast Update

FORECAST SUMMARY: MondAY, December 4, 2023, through FRIDAy, December 8, 2023

PM-2.5:   24-hour average Fine Particulate concentrations are also expected to be Good to Low Moderate.

FORECAST DISCUSSION:

A departing low pressure provided early Monday morning showers which will diminish during the day as drier air enters the region with a short-lived high pressure ridge. 

A clipper system is expected by the Tuesday morning time frame bringing additional precipitation.  Tuesday temperatures are expected to reach the upper 30’s so any morning snow showers will quickly become rain showers. 

By midweek, an upper air high pressure ridge should push out any lingering wet weather and position the state in a strong southwest wind pattern.  Thursday’s temperatures are expected to reach the mid-40’s and Friday’s temperatures could reach the low-50’s with breezy winds.

Air Quality should remain mostly Good but could reach the Low Moderate range in some areas with the warmer temperatures and ample moisture.

More precipitation may be on the horizon during the weekend and that chance will be discussed in the Friday forecast.

EXTENDED FORECAST:

Air Quality should be generally Good to Low Moderate entering the weekend.

Next Forecast Update: Friday, December 8, 2023

12/1/2023 Forecast Update

FORECAST SUMMARY: MondAY, December 1, 2023, through FRIDAy, December 4, 2023

PM-2.5:  24-hour daily average Fine Particulate concentrations will range between middle Good and middle Moderate through the forecast period.

FORECAST DISCUSSION:

The week ends on a quiet note across the Upper Peninsula and far northern Lower Michigan with weak high pressure dominating; however, conditions differ further south. Weather systems moving along a stalled boundary near the Michigan, Indiana, and Ohio borders bring cold rain in the forecast across southern Michigan, a mix of rain and snow in central locations, and primarily snow further north. The first of these is moving through early Friday, with a second expected late Friday into early Saturday. Each of these disturbances originates from the southern Plains States, tracking northeast into the southern Great Lakes region. A third moves in on Sunday, bringing yet another chance for rain and/or snow. The exact timing and placement of the systems as they move into the region will determine where liquid precipitation will fall in lieu of snow; however, at this time, none of them are expected to produce significant snow accumulations.

Good to low-Moderate daily concentrations of PM2.5 have been seen across the state this week. As often happens near frontal boundaries, concentrations are increasing into the Moderate range across the south early Friday. While a few hourly concentrations, primarily in the southeast, may reach low-end USG, this should be short-lived, with daily averages no higher than Moderate expected. The on-and-off systems through early next week should keep the atmosphere mixed, not allowing for long-term stagnant periods. Also, with the main systems tracking across the southern Great Lakes region, a primary easterly wind flow can be expected. However, without a good northerly wind flow in the wake of these disturbances, PM2.5 increases may not be entirely cleared, leading to Moderate readings at times. Daily averages of PM2.5 during this forecast period will likely remain between upper-Good and middle-Moderate.

EXTENDED FORECAST:

Extended models show dry conditions starting the new workweek, but another system is forecast to drop in from the northwest Tuesday. Air quality in the extended period is expected to continue to range between Good and Moderate.

Next Forecast Update: Monday, December 4th, 2023

11/27/2023 Forecast Update

FORECAST SUMMARY: MondAY, November 27, 2023, through FRIDAy, December 1, 2023

PM-2.5:  24-hour average Fine Particulate levels will range mostly Good through mid-week, with some Moderate towards the end of the forecast period.

FORECAST DISCUSSION:

The week begins on a cold note with gusty west/northwest winds and snow showers, which are primarily lake effect in nature. An upper-level system later Monday into Tuesday will enhance snow showers; however, the highest accumulations remain in the most prone northwest flow lake effect locations. Ridging builds in for a short time before another shortwave produces additional snow showers early Wednesday. On Thursday, there is some uncertainty about the timing of two weather systems: a front dropping in from the northwest and another system moving in from the southwest. Even with that uncertainty, temperatures should be increasing to near-normal levels by the end of the workweek.

Weaker winds under high pressure allowed for some Moderate PM2.5 concentrations in the southeast on Saturday and more widespread across southern portions of the state on Sunday. Hourly readings in the low-Moderate range were experienced early Monday morning in the southeast, but strong northwest winds will allow levels to fall to Good as the day progresses. The active pattern setting up for much of the week should keep daily PM2.5 concentrations primarily Good through Wednesday. The southern portion of the state may be between weather systems Thursday, with better chances for precipitation Friday. Concentrations of PM2.5 during this period will likely be a mix of middle-Good to low-Moderate.

EXTENDED FORECAST:

Extended models show dry conditions on Saturday, with another system for early next week. This air quality forecast will be updated on Friday, but pollution levels higher than low-Moderate are not expected in the long-term forecast.

Next Forecast Update: Monday, December 1st, 2023

11/24/2023 Forecast Update

FORECAST SUMMARY: MondAY, November 24, 2023, through FRIDAU, November 27, 2023

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

FORECAST DISCUSSION:

As we all wake up after the Turkey Day festivities which were had yesterday, Thursday, we see more of the same with relatively cloudy skies and surface temperatures in the mid-30s for the majority of the state. Our weather stays pretty quiet today and into tomorrow, as a High-pressure system hangs around the region well into the weekend. As Sunday approaches, however, the first state-wide snow system will impact Michigan with low accumulation amounts for most areas, but a signal for the start of winter precipitation, nonetheless. Snow will fall on and off essentially all-day Sunday and into Monday, with winds picking up as the system, which is bringing the snow, exits to the east. Highest total accumulations are expected to be in the 2-3 inch range on the west side of the state with opportunity for lake-effect influencing higher totals. Monday will see left over snow showers and windy conditions but look to improve throughout the day.

For PM-2.5, concentrations will be similar to what was seen this week – Good, but with some morning hour Moderate concentrations. Overall air quality will be Good, however.

EXTENDED FORECAST:

Seasonally normal temperatures and overall weather start off the next work week as air quality remains Good.

Next Forecast Update: Monday, November 27th, 2023

11/20/2023 Forecast Update

FORECAST SUMMARY: MondAY, November 20, 2023, through FRIDAU, November 24, 2023

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

FORECAST DISCUSSION:

Happy Thanksgiving to all those who celebrate as we, Michiganders, dive back into seasonably normal temperatures this week after a week of above normal temperatures and overall beautiful weather. Today, Monday, will see temperatures in the upper 30s with relatively cloudy skies for most of the state. A low-pressure system approaches us late tonight through tomorrow which will bring rain for the majority of the state with some mixed precipitation the more north one travels. This precipitation will last essentially all day, but we dry out as Wednesday evening approaches. Once the low-pressure exits to the east early Wednesday morning, a cold front follows behind it which will keep surface temperatures cool and the skies relatively cloudy. Turkey Day (Thursday) will see the continuation of Wednesday weather with mostly cloudy skies and surface temperatures scattered from low-30s to low-40s throughout the state. Northerly winds will dominate this week with some easterly and westerly component mixed in, but the northerly winds will be the reason for a return to seasonably normal temperatures. Friday will see cooler temperatures and cloudier conditions to round off the work week.

Due to the northerly winds, and relatively consistent wind speeds, PM-2.5 concentrations should not be an issue this week. As always, there is a chance of concentration build up in the morning hours due to stagnant conditions, but those conditions will dissipate as the days carry on. Overall PM-2.5 air quality will be on the Good range.

EXTENDED FORECAST:

This weekend presents us with more of the same from the work week with slightly cooler temperatures throughout. Overall air quality will remain Good.

Next Forecast Update: Friday, November 24, 2023

11/17/2023 Forecast Update

FORECAST SUMMARY: Friday, November 17, 2023, through Monday, November 20, 2023

Ozone: Ozone season is now over and will start forecasting again in the spring of 2024.

PM-2.5:  24-hour average Fine Particulate concentrations are also expected to be mostly Good.

FORECAST DISCUSSION:

A cold front is passing through Michigan, Friday morning, providing showers and clouds to the area.  High pressure will build in behind the front bringing clearing skies and cooler temperatures during Friday afternoon.  Clear skies are expected to persist through the weekend with frosty mornings and daytime highs reaching the upper 40’s.  Air Quality is expected to be mostly Good through the weekend.

For the upcoming holiday week, a mid-week front is expected to pass, late Tuesday, bringing a significant cool down for midweek and Thanksgiving Day.  While temperatures are expected to be much cooler during the Thanksgiving holiday, no travel issues currently appear in the forecast.  Air Quality is expected to remain in the Good Category through the holiday.

EXTENDED FORECAST:

Air Quality should be generally Good to start the holiday week.

Next Forecast Update: Monday, November 20, 2023

11/13/2023 Forecast Update

FORECAST SUMMARY: Monday, November 13, 2023, through Friday, November 17, 2023

Ozone: Ozone season is now over and will start forecasting again in the spring of 2024.

PM-2.5:  24-hour average Fine Particulate concentrations are also expected to be mostly Good.

FORECAST DISCUSSION:

A mostly dry and mild week is underway with temperatures running above normal.  For the beginning of deer firearm season, we can expect continued dry, seasonably warm, breezy weather, during midweek, with no chance for tracking snow.  In terms of Air Quality, we should remain mostly Good for the forecast period.

The unseasonably warm temperatures and dry weather looks to hang on through Thursday.  A cold front and associated band of rain showers then ushers in cooler air Thursday night and Friday.  Weekend high temperatures still look to reach the upper 40’s, with dry weather, following that Friday frontal passage.  

It should be a good week to be outdoors enjoying the clear skies, warmer weather, and Good Air Quality!

EXTENDED FORECAST:

Air Quality should be generally Good to start the weekend.

Next Forecast Update: Friday, November 17, 2023

11/09/2023 Forecast Update

FORECAST SUMMARY: thursday, november 9, 2023, through monday, november 13, 2023

Ozone: Ozone season is now over and will start forecasting again in the spring of 2024.

PM-2.5:  24-hour average Fine Particulate levels will range mostly Good, with some Moderates mostly in southern locations early Monday and/or Wednesday.

FORECAST DISCUSSION:

Dry air is quickly moving in Thursday behind the departing system, which brought a wet midweek to the state. Aside from a small chance for lake effect precipitation in west Michigan Friday night, dry conditions prevail throughout the forecast period. The dry weather can be attributed to high pressure sliding in from the west during the coming weekend. Gusty winds with a westerly component can be expected Thursday and Friday. Wind speeds decrease Saturday as the high moves overhead, but winds pick up again from the southwest early next week as the center of the high moves east of the state.

Air quality over the past few days has been ranging Good statewide, and stronger westerly winds should keep Good levels Thursday and Friday. Lower wind speeds Saturday into Sunday may allow for localized buildup of fine particulate levels, especially during the morning hours. Daily averages of fine particulate may reach low Moderate at southern locations; otherwise, Good readings continue.

EXTENDED FORECAST:

Extended models show a system passing north of Lake Superior on Monday. This system reinforces stronger winds that should help keep fine particulate mostly Good as we move into the new workweek.

Next Forecast Update: Monday, November 13, 2023

11/06/2023 Forecast Update

FORECAST SUMMARY: Monday, November 6, 2023, through Thursday, November 9, 2023

Ozone: Ozone season is now over and will start forecasting again in the spring of 2024.

PM-2.5:  24-hour average Fine Particulate levels will range mostly Good, with some Moderates mostly in southern locations Monday and/or Wednesday.

FORECAST DISCUSSION:

This past weekend, some smoke made its way into the southern portion of the state, mostly due to seasonal fire activity in the central U.S. While not nearly as bad as this past summer, the smoke did aid in increasing PM2.5 concentrations on Saturday and Sunday. Daily averages Saturday remained Moderate; however, a couple monitors in the southeast recorded daily averages in the low USG category Sunday. Increased hourly readings remain at a few southeast monitors Monday morning, but the plume is expected to move out during the day. Hourly concentrations of PM2.5 may reach USG at a few southeast sites Monday; however, readings should improve during the day, with mostly Moderate daily averages expected.

On-and-off storm systems are forecast this week. The first is a low-pressure area over Lake Superior on Monday, tracking east into Tuesday. Associated precipitation ends late Monday as the system pulls east, and northerly winds develop as high pressure sinks in from the north. Quiet conditions will be short-lived as the next storm moves in from the west late Tuesday into Wednesday. A wet midweek gives way to dryer conditions for the end of the week.

Northerly winds developing later Monday into Tuesday allow for mostly Good air quality on Tuesday. Winds change to a southerly direction on Wednesday ahead of the approaching weather system. There are some seasonal fires and wildfires ongoing south of Michigan across the east and southeast U.S. It’s uncertain if any associated plumes will track north into our area; however, this is something we will keep an eye on, updating this forecast if necessary. On Thursday, winds switch back to the north, so any increase in PM2.5 Wednesday should not linger. We are forecasting Moderate PM2.5 for Wednesday to account for smoke potential, but any increase should improve towards the Good range Thursday into Friday under northerly winds.

EXTENDED FORECAST:

Extended models show dry, cool conditions as we move into the coming weekend. Northerly winds during this period should keep PM2.5 mostly Good.

Next Forecast Update: Thursday, November 9, 2023

11/03/2023 Forecast Update

FORECAST SUMMARY: Friday November 3, 2023, through Monday November 6th, 2023

Ozone: Ozone season is now over and will start forecasting again in the spring 2024.

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

FORECAST DISCUSSION:

Michigan ends the week on a higher note than when started with surface temperatures climbing into the upper 40s and low-mid 50s. Southerly flow has been building since yesterday, Thursday, bringing in warmer air and clearer skies. Today, Friday will see relatively sunny skies and winds blowing from the SSW. Overnight tonight, a weak system traverses the state with a cold front associated with it, so there may be a chance of a popup rain shower. Due to the weak cold front, tomorrow, Saturday may see slightly cooler temperatures, but the majority of Michigan will see temperatures in the upper 40s to low 50s. Sunday continues the trend of surface temperatures in the upper 40s but may see more sunshine than what is expected on Saturday. Sunday night into Monday presents us with another Low-pressure system which will influence our weather throughout the day on Monday as we start Monday warm and dry, and end cooler and wet.

For air quality, the Ozone season is now over so we will stop updating the Ozone forecast in our updates until the 2024 season starts in the spring. PM-2.5 will continue to see Moderate increases during the morning hours when winds are light. The past few days have seen rather strong winds gusts throughout the day to dissipate PM-2.5 concentrations, so this will be expected the next few days as well.

EXTENDED FORECAST:

As stated above, an early week system is expected to impact our state Monday into Tuesday. This will help keep overall air quality Good.

Next Forecast Update: Monday November 6th, 2023

10/30/2023 Forecast Update

FORECAST SUMMARY: Monday October 30th, 2023 through Friday November 3rd, 2023

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

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

FORECAST DISCUSSION:

As October comes to a close this week, Mother Nature will be in the spirit of Halloween by providing much of Michigan with a chance of seeing the ever-dreaded, and scary “S-word”—snow. A Low-pressure system and associated cold front will eclipse our state tomorrow, Tuesday, and make its way east overnight into Wednesday. This will drop, and keep, high temperatures in the 30s for all of Michigan for Tuesday and into Wednesday. Wednesday will have northerly flow which will be aiding in keeping temperatures cool, along with starting the lake-effect snow machine Michigan sees around this time every year. Michiganders along the Lake Superior and Lake Michigan shorelines should expect spotty lake-effect snow essentially all week, but any snow showers are expected to remain as flurries, or dustings, at best. Winds look to shift as we get into the latter half of the week, with a cold front-turning-into-warm front-scenario occurring Thursday into Friday, raising our high temperatures back into the low-to-mid 40s. The warming trend continues into the weekend with temperatures creeping back into the 50s in some areas.

For air quality, Ozone will be in the Good range as the Ozone season comes to a close and we will soon stop forecasting Ozone as we get deeper into Fall and into Winter. For PM-2.5, overall concentrations will be in the Good range throughout the week, but there are chances for atmospheric inversions throughout the week as well. These inversions will mainly occur in the morning hours when surface winds are light and will dissipate as the days carry on and winds increase.

EXTENDED FORECAST:

As stated earlier, a weekend warmup is on the horizon for much of Michigan, and overall air quality is expected to remain Good.

Next Forecast Update: Friday, November 3, 2023

10/27/2023 Forecast Update

FORECAST SUMMARY: Friday, October 27, 2023, through Monday, October 30, 2023

Ozone: 8-hour average ozone concentrations are expected to be mostly Good.

PM-2.5:  24-hour average Fine Particulate concentrations are also expected to be mostly Good.

FORECAST DISCUSSION:

This Friday forecast marks the end of the last full week of the 2023 ozone season.  A brief recap of the season shows that it was a bit more active than average.  However, several of the high ozone episode days can be blamed on the wildfire smoke which caused exceptionally bad Air Quality events during June.

Air Quality for the current week has been mostly Good.  The warmer weather enjoyed during the week will end, today, as a cold front slides through.  It will be followed by considerably cooler and drier air making Saturday a good day for football with crisp temperatures topping out around 50 degrees.

Good Air Quality will continue through the weekend and into the next work week.  The long-range forecast has snow showers predicted for Halloween on Tuesday.  Autumn has truly arrived, and the leaves seem to be in full color for a good weekend of viewing. 

EXTENDED FORECAST:

Air Quality should be generally Good to start the next work week.

Next Forecast Update: Monday, October 30, 2023

10/23/2023 Forecast Update

FORECAST SUMMARY: Monday, October 23rd, 2023, through Friday, October 27th, 2023

Ozone: 8-hour average ozone concentrations are expected to be Good.

PM-2.5:  24-hour average Fine Particulate concentrations are also expected to be mostly Good to Low Moderate.

FORECAST DISCUSSION:

After a chilly start to Monday morning, temperatures are expected to rebound to above average for most of the week. The forecast area will be in a warm air sector and temperatures for Tuesday are expected to be in the low 70’s before settling into the mid-60’s for the rest of the work week.

While a few showers may pop up during Monday and early Tuesday, most areas should be dry. This will be welcome news for harvesters who have been sidelined with wet weather and muddy fields. Unfortunately, by Wednesday, wet weather moves back into the region with the possibilities of significant precipitation for the rest of the week.

The warmer weather should last into the weekend before a cold front moves through and temperatures drop back into the 50’s.

Air Quality during the week should be mostly Good. Ozone, at this late date, is no longer an issue. Fine particulates should be mostly Good but the abundance of moisture with warmer temperatures may produce some Low Moderate readings, especially in the more southern and more populated areas.

Fortunately, wildfire smoke season appears to be mostly behind us as most of the large Canadian wildfires are now contained to the western and northwestern most provinces.

EXTENDED FORECAST:

Air Quality should be generally Good to Low Moderate to start the weekend.

Next Forecast Update: Friday, October 27th, 2023

10/20/2023 Forecast Update

FORECAST SUMMARY: FRIDAY October 20th, 2023, through Monday October 23th, 2023

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

PM-2.5:  PM-2.5 levels will range mostly Good, with only scattered low Moderates.

FORECAST DISCUSSION: The week ends with clouds and showers thanks to a system tracking east during the day Friday and another dropping in from the northwest Saturday. Conditions dry out and clouds decrease Sunday into Monday as high-pressure ridging builds in. Some much-needed sunshine is in the forecast as well; however, cooler temperatures continue.

As for air quality, PM2.5 concentrations have been mostly Good with only a handful of low-Moderate readings Thursday at some of our southern monitors. The two weather systems moving through Friday and Saturday should keep the atmosphere well mixed, keeping PM2.5 Good, then northwesterly winds Sunday will allow Good concentrations of PM2.5 to linger into early next week. Ozone has not been an issue, and Good concentrations will continue through the forecast period.

EXTENDED FORECAST:

Extended models show an active period setting up as next week progresses, with precipitation back in the forecast. Southerly winds, coupled with increased moisture, could bring PM2.5 into the low Moderate range.

Next Forecast update: Monday, October 23, 2023

10/09/2023 Forecast Update

FORECAST SUMMARY: Monday October 9th, 2023, through Friday October 13th 2023

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

PM-2.5: PM-2.5:  PM-2.5 concentrations are expected to be in the Good range with some hourly low-Moderates.

FORECAST DISCUSSION: Fall has definitely fallen upon us here in Michigan with average surface temperatures remaining in the 50s for the foreseeable future and leaves ever-changing in color. This week also has its fair share of rain in the forecast with essentially every day this week having a chance of rain somewhere throughout the state. These cooler temperatures are solely due to northerly winds which will dominate the weather pattern this week. The main threat of rain this week will be Thursday and through the weekend as a Low-pressure system makes its way toward the Great Lakes from the southwest. Although the Low-pressure itself will stay just to our south, Michigan will still see impacts in the form of rain and some breezy to windy conditions. As of now, these rainy and breezy conditions look to last through the weekend.

In terms of air quality, the Ozone season is slowly but surely winding down with days becoming shorter and temperatures staying cooler. Coupled with the rain this week, Ozone will be in the Good range with rain keeping the airmass clean and cooler temperatures inhibiting the development of Ozone. Last week, we saw PM-2.5 concentrations rise into the USG range for an hour or two mainly in the Detroit and other populated areas. This is typical during early morning commutes with light winds. We usually see those conditions as mornings become cooler and, almost like clockwork, in the wintertime due to surface-level atmospheric inversions trapping air from dispersing. We may see those kinds of concentrations this week, but rain and wind later in the week will help keep PM-2.5 concentrations in the Good range as well.

EXTENDED FORECAST: The weekend continues what the work week ends with: rain and wind. Sunday starts to see the rain lifting off, but northerly winds carry on, with surface temperatures in the 50s. Overall air quality will be Good.

Next Forecast Update: Friday, October 13, 2023

10/06/2023 Forecast Update

FORECAST SUMMARY: Friday, October 6, 2023, through Monday, October 9, 2023

Ozone: 8-hour average ozone concentrations are expected to be mostly Good.

PM-2.5: PM-2.5:  24-hour average Fine Particulate concentrations are also expected to be mostly Good.

FORECAST DISCUSSION: As predicted during my Monday forecast, the 80-degree weather enjoyed during the first half of the week, exited the state during passage of a late-week cold front.  A secondary front will also pass through the state, Friday afternoon, ushering in much cooler air for the weekend.  With the northwesterly flow, I am expecting Good Air Quality with no problems from ozone, fine particulates, or smoke.

An upper-level low, that will move through Saturday, will influence our weather over the next week.  As the cooler air travels across Lake Michigan, we can expect the weekend in the western half of the state to be mostly cloudy with periodic rains showers and perhaps even a rumble or two of thunderstorms.

With the shortening days, ozone will cease to be a concern and the ozone season will officially end at the end of October.  Wildfires in Canada are on the wane, as well.  Many of the fires in eastern and central Canada that caused so many issues in our Midwest and Eastern seaboard states during June have been extinguished or reduced and have become less of a problem.  Most of the large Canadian fires still burning are now contained in the Alberta, British Columbia, and Northwest Territories provinces in western Canada.

Columbus Day (Monday) should show a gradual return to clearer skies but still cooler temperatures with daily highs in the low 50’s and continued Good Air Quality.

EXTENDED FORECAST: Air Quality should be generally Good to start the next work week.

Next Forecast Update: Monday, October 9, 2023

10/02/2023 Forecast Update

FORECAST SUMMARY: Monday, October 2, 2023, through Friday, October 6, 2023

Ozone: 8-hour average ozone concentrations are expected to be a mixture of Good to Moderate through Wednesday then Good.

PM-2.5: 24-hour average Fine Particulate concentrations are also expected to be a mixture of Good to Moderate through Wednesday then Good.

FORECAST DISCUSSION: The high pressure ridge currently over the Great Lakes region will persist through Wednesday and, in fact, some locations could see record high temperatures during Tuesday. 

While very rare to see significant ozone development in Michigan during October, it is not unlikely that we could see some High Moderates along the Lake Michigan coast during Tuesday.  With the shorter hours of daylight, getting to USG would be difficult although not impossible.  However, since the possibilities are too remote and unlikely, no type of Action Day is being considered.

A pair of quick hitting cold fronts will put an end to the current summer-like conditions.  The first cold front will arrive during the early Thursday morning time frame.  I expect high temperatures Thursday afternoon will be some 20 degrees cooler than what we will see during the first half of the week.  Any Air Quality issues should be removed at that time.

The second front will follow-up during Friday and usher in significant cooler air.  I expect high temperatures on Saturday to be 30 degrees cooler than the high temperatures we will see during Monday through Wednesday.

EXTENDED FORECAST: Air Quality should be generally Good to start the next work week.

Next Forecast Update: Friday, October 6, 2023

09/29/2023 Forecast Update

FORECAST SUMMARY: Friday, September 29, 2023, through Monday, October 2, 2023

Ozone: 8-hour average Ozone concentrations will range Good to Moderate.

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

FORECAST DISCUSSION: A frontal boundary brings precipitation in the forecast Saturday in the Upper Peninsula while high pressure produces dry weather across the rest of the state. Temperatures increase through early next week as warmer air ushers in on a southerly wind. Temperatures for the end of September/early October will be more summer-like than fall-like. Highs climb into the 70s Saturday and approach the 80-degree mark early next week. After the Saturday precipitation up north, the next chance for precipitation across the state should hold off until midweek next week.

As for air quality, both PM2.5 and ozone have been Good the past few days and Good readings should continue Friday. Less cloud cover in the Lower Peninsula and warmer surface and upper-level temperatures on a southerly wind makes weather conditions conducive for ozone starting Saturday, lasting through the period. What hampers ozone development, however, is less solar radiation that makes ozone generation less likely. While we anticipate ozone to increase into the Moderate range across parts of the state, readings into the USG range are not likely.

The current weather scenario does not bring wildfire plumes over the state which would result in increased PM2.5. But weaker winds from the south may allow for increased levels, especially in the southeast portion of the state. PM2.5 concentrations will range from middle Good to middle Moderate.

EXTENDED FORECAST: Warmer/dry conditions lingering early next week keep the chance for Moderate ozone and PM2.5 in the extended forecast.

Next Forecast Update: Monday, October 2, 2023