05/22/2023 Forecast Update

FORECAST SUMMARY: Monday, May 22nd, 2023, through Friday, May 26th, 2023

OZONE:  8-hour average ozone concentrations are expected to be mostly Good with the possibility for scattered Low Moderate during the first couple of days of the forecast period.

PM-2.5:  24-hour average Fine Particulate concentrations are also expected to be mostly Good to Moderate through the forecast period.

FORECAST DISCUSSION:

For those outside yesterday (Sunday), you may have notice that the sun appeared to be on a dimmer switch.  It was a bit surreal to have no clouds but gray skies and only weak shadows showing.  This was a result of wildfires in Canada sending elevated smoke down through the Midwest.  Fortunately, the layer of smoke is staying elevated and not filtering down to the ground in any significant amounts.  As of Monday morning, that layer of smoke is directly still over Michigan.  The models are predicting a lessening of the smoke layer as the week progresses, but we may have some of the smoke that will linger for a while.

In terms of our Air Quality, I am anticipating that the overhead smoke will not have much direct impact on our ground level Air Quality.  The models are predicting mostly clear skies all week and through the holiday weekend and Tuesday will likely be the warmest day of the week.  But the overhead smoke should dim the solar radiation enough to discourage significant ozone formation. 

A dry cold front will sweep through the region early Wednesday morning to clear out any surface level air contaminants.  Cooler, dryer air, along with high pressure will build in behind the front and keep our Air Quality mostly Good for the remainder of the work week.

The holiday weekend also looks mostly clear with warming by Sunday.  As a result, I will be updating this forecast on Friday but not anticipating any problems, at this time.

EXTENDED FORECAST:

Air Quality should be mostly Good begin the next work week.

Next Forecast Update: Friday, May 26th, 2023

05/19/2023 Forecast Update

FORECAST SUMMARY: Friday, May 19th, 2023, through Monday, May 22nd, 2023

OZONE: Ozone concentrations will range from the Good to Moderate range.

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

FORECAST DISCUSSION:

This forecast summary will mainly focus on the wildfire smoke approaching Michigan from wildfires in Alberta, Canada. For the majority of the week, regional winds have been northwesterly which have been bringing wildfire smoke and associated PM-2.5 concentrations closer to the Midwest. Several states to our west have issued Air Quality Alerts for PM-2.5. One of the main driving components of PM-2.5 concentrations reaching the ground is the cold front traversing the area from NW to SE. In this situation, with the cold front moving through the area, the wildfire smoke essentially pools along the front and the air behind the front sinks, thus bringing PM-2.5 concentrations closer to the surface. This is why we are able to see PM-2.5 concentrations near the surface and the wildfire smoke aloft in the upper atmosphere because not all of the smoke reaches the ground.

In Michigan’s case, the wildfire smoke has travelled quite a long distance and that distance has helped to disperse some of the concentrations. The cold front is expected to cross Michigan throughout the day today so PM-2.5 hourly concentrations may increase into the high Moderate range. Along with a possible increase in hourly concentrations, some areas across Michigan may notice a smoke smell as the front approaches along with hazy skies which have been seen throughout this week. We expect the 24-hour averages for PM-2.5 to be in the Moderate range, but this event is worth noting, nonetheless. The front crossing Michigan along with the rain will help dissipate and disperse the concentrations further so we do not expect these concentrations to stick around. Western Michigan, especially the western UP, may experience a smoke smell more so than eastern Michigan because of the frontal passage dispersing concentrations along with the orientation of the front.

Saturday may have left over rain in the morning hours but slowly clearing up in the afternoon with winds from the NW. Sunday continues where Saturday leaves off with NW winds and sunny skies with temperatures in the 70s thanks to a High-pressure setting up to our south.

EXTENDED FORECAST:

The High-pressure moves off to our north, shifting winds to more easterly but temperatures remain the same. Overall air quality looks to be Good to start off next week.

Next Forecast Update: Monday, May 22nd, 2023

05/15/2023 Forecast Update

FORECAST SUMMARY: Monday May 15th, 2023, through Monday May 22nd, 2023

OZONE: Ozone concentrations will range from Good to Moderate throughout the forecast period.

PM-2.5: PM-2.5 concentrations are expected to range from Good to low-Moderate throughout the forecast period.

FORECAST DISCUSSION:

The beautiful Spring weather from the weekend continues into this week with ample sunshine and surface temperatures in the upper-60s and 70s throughout the Great Lakes State. This is attributed to regional High-pressure clearing the way for clear skies and temperatures near seasonal norms. Along with sunny skies and warm temperatures, winds should be relatively light from the WNW. This weather pattern sticks around through Wednesday until a Low-pressure system drifts into the area from the north on Thursday. This will shift winds to more southerly flow and cloudier conditions for the end of the week. Precipitation does not look to start until early Friday morning and will be on and off throughout the day on Friday.

 The rain may hang around to start off the weekend with temperatures in the 60s and possibly 70s as we approach Sunday. Winds will shift back for the weekend and into next week due to a High-pressure system setting up just to our west.

For air quality, with most of the week being under northerly flow, the airmass will be relatively clean with little pollutants. When winds shift to more southerly flow later this week, concentrations may uptick but the rain on Friday will help clean out any buildup. Concentrations should remain low with winds shifting back to northerly for the weekend. Cooler temperatures will help keep Ozone production at bay although we will have ample sunlight to start off the week. There might be some Moderate concentrations on Tuesday, but only should hang around the mid-Moderate range. Light winds in the mornings may allow for PM-2.5 concentrations to increase but afternoon increase in winds will help blow those concentrations out of the area.

EXTENDED FORECAST:

Monday will continue what Sunday provides for us with winds shifting to more southerly to start off next week. Overall air quality should remain Good.

Next Forecast update: Monday, May 22, 2023

05/08/2023 Forecast Update

FORECAST SUMMARY: Monday, May 8, 2023, through Monday, May 15, 2023

Ozone: 8-hour average Ozone concentrations will range between Good and Moderate through the forecast period.

PM-2.5: 24-hour average Fine Particulate will range from Good to low-Moderate.

FORECAST DISCUSSION:

Low pressure tracking along a west to east frontal boundary positioned south of the state Monday could triggered precipitation in the southern areas; otherwise, high pressure dropping in from the north provides dry conditions. High pressure dominates through mid-week with temperatures moderating Tuesday into Thursday. The next chance for precipitation arrives Friday as the high departs east and southeast/southerly winds increase moisture over the region.

As for air quality, clouds and precipitation chances keep pollution levels Good Monday. The only exception would be for of a monitor or two in the southeast to reach low-end Moderate for fine particulate. Clouds will be decreasing west to east Tuesday as surface temperatures increase a few degrees. Plentiful sunshine generally makes ozone more conducive; however, cooler upper-level temperatures and northerly winds should keep both ozone and fine particulate generally Good. As the high slides overhead, wind speeds decrease Wednesday and by Thursday the surface flow turns more south/southeasterly. Skies will be sunny and surface temperatures increase both days, but what likely hampers ozone development are cooler upper-level temperatures. While the likelihood of Moderate ozone and fine particulate spreads Wednesday into Thursday, readings higher than Moderate are not anticipated.

EXTENDED FORECAST:

Extended models show a weather system in the region keeping clouds and precipitation chances for the weekend into early next week. Ozone levels should range mostly Good while fine particulate may be Good to low Moderate.

Next Forecast update: Monday, May 15, 2023

5/01/2023 Forecast Update

FORECAST SUMMARY: Monday, May 1, 2023, through Monday, May 8, 2023

OZONE: 8-hour average ozone concentrations are expected to be mostly Good with the possibility for scattered Low Moderate during that latter half of the forecast period. 

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

FORECAST DISCUSSION:

As we enter the month of May, the cool, damp weather of the past few days is expected to persist into mid-week under a slow moving low-pressure system.  By Wednesday, that cold, low-pressure system should be nudged out by an approaching high-pressure ridge.  That will chase the dampness away under sunny skies, but temperatures will likely remain a bit cooler than normal for this time of year.

In terms of Air Quality, ozone should not be a problem, even under the clear skies for the latter half of the forecast period.  Thursday will have mostly calm conditions which could allow some Low Moderate ozone creep in the urban areas prone to stagnation.  Friday through the weekend is showing easterly winds which typically do not cause ozone issues although some areas east of Detroit could show some Low Moderate conditions.  Cooler temperatures will help keep concentrations from creeping up, too high.

Fine particulate concentrations will likely follow the same pattern with mostly Good concentrations with the possibility of Low Moderate in the areas prone to urban stagnation during the latter half of the week.

EXTENDED FORECAST:

Air Quality should be mostly Good begin the next work week.

NEXT FORECAST UPDATE: Monday, May 8, 2023

04/24/2023 Forecast Update

FORECAST SUMMARY: Monday, May 1, 2023, through Monday, May 8, 2023

OZONE: 8-hour average ozone concentrations are expected to be mostly Good with the possibility for scattered Low Moderate during that latter half of the forecast period. 

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

FORECAST DISCUSSION:

As we enter the month of May, the cool, damp weather of the past few days is expected to persist into mid-week under a slow moving low-pressure system.  By Wednesday, that cold, low-pressure system should be nudged out by an approaching high-pressure ridge.  That will chase the dampness away under sunny skies, but temperatures will likely remain a bit cooler than normal for this time of year.

In terms of Air Quality, ozone should not be a problem, even under the clear skies for the latter half of the forecast period.  Thursday will have mostly calm conditions which could allow some Low Moderate ozone creep in the urban areas prone to stagnation.  Friday through the weekend is showing easterly winds which typically do not cause ozone issues although some areas east of Detroit could show some Low Moderate conditions.  Cooler temperatures will help keep concentrations from creeping up, too high.

Fine particulate concentrations will likely follow the same pattern with mostly Goodconcentrations with the possibility of Low Moderate in the areas prone to urban stagnation during the latter half of the week.

EXTENDED FORECAST:

Air Quality should be mostly Good begin the next work week.

NEXT FORECAST UPDATE: Monday, May 8, 2023

04/17/2023 Forecast Update

FORECAST SUMMARY: Monday, April 17, 2023, through Monday, April 24, 202323

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

PM-2.5: 24-hour average Fine Particulate will range primarily Good with only small chances for Moderate.

FORECAST DISCUSSION:

The weather conditions from last week caused increases in both Ozone and Fine Particulate, warranting our first Action Day this season for ozone along the western lakeshore and in the southeast on Friday. USG ozone concentrations were seen at two southwest lakeshore monitors, and one southeast location. Clouds moved in early enough Saturday to keep western and central areas Moderate for ozone, however, further east sunshine prevailed longer, and a handful of monitors reached low-end USG. Fine particulate also increased with daily averages in the 20’s at several locations. The highest concentrations were Friday and Saturday in the southeast and one monitor reach just over the USG threshold on Saturday. The airmass over the region was a “dirty” airmass and increases in pollution were experienced in neighboring states as well. Smoke also prevailed over the region; however, more research would be needed to determine if smoke played a role in increased pollution levels.

The new week began with a cold front Sunday which ended the summer-like conditions, ushering in colder than normal temperatures and snow showers. Low pressure just north of the region dominates Monday and Tuesday with cool northerly winds and scattered snow showers. High pressure settles in briefly Wednesday before the next weather system brings a warm front north Thursday and then an associated cold front Friday. A quick temperature warmup Thursday allows precipitation to fall as rain, but another cool down is expected for the end of the week.

Good pollution levels should prevail Monday and Tuesday thanks to stronger winds with a northerly component. Weak high pressure sliding south of the state Wednesday could allow for increases in fine particulate to the low Moderate range, but ozone should remain Good. Warmer conditions move in Thursday, along with stronger winds and chances for precipitation. Fine particulate may remain low Moderate; however, ozone should average mostly Good. Precipitation may linger into Friday as the system tracks east. Fine particulate may remain Moderate in the southeast; otherwise, pollution levels will be Good.

EXTENDED FORECAST:

Extended models show high pressure settling in from the north during the second half of the weekend. Conditions will dry out as the weekend progresses, and temperatures will fall to below seasonable levels. Air quality readings are expected to be mostly Good during the weekend into early next week.

NEXT FORECAST UPDATE: Monday, April 24, 2023

04/14/2023 Forecast Update

FORECAST SUMMARY: Friday, April 14, 2023, through Monday, April 17, 2023

OZONE: 8-hour average ozone concentrations are expected to be mostly Moderate to USG during Friday then Good to Low Moderate for the remaining forecast period.

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

AN ACTION DAY ADVISORY REMAINS IN EFFECT FOR THE FOLLOWING MICHIGAN COUNTIES FOR FRIDAY, APRIL 14: ALLEGAN, BENZIE, BERRIEN, CASS, GRAND TRAVERSE, KALAMAZOO, KENT, LEELANAU, MANISTEE, MUSKEGON, OCEANA, OTTAWA, MASON, ST. JOSEPH, AND VAN BUREN

FORECAST DISCUSSION:

Everything appears to still be on track for elevated ozone in our sensitive areas for Friday.  Fortunately, this looks to be a one-day event.  An approaching cold front will bring in increasing cloud cover on Saturday and the front should pass on Sunday.  This will put an end to this episode.

The air behind the front will be chilly for the first half of next week to remind us that this is still early Spring.  But the Air Quality will be Good.

The earliest an Action Day had been called since the start of the program was May 4, 1999 in SE Michigan.  So, this marks the earliest Action Day in the history of the program. 

EXTENDED FORECAST:

Air Quality should be mostly Good begin the next work week.

Next Forecast update: Monday, April 17, 2023

04/13/2023 Forecast Update

FORECAST SUMMARY: Thursday, April 13, 2023, through Friday, April 14, 2023

OZONE: 8-hour average ozone concentrations are expected to be Moderate to USG through the forecast period.

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

FORECAST DISCUSSION:

While highly unusual for mid-April, conditions under a slow-moving high-pressure system have created conditions for elevated ozone, this week.  The past few days have seen 1-hour concentrations in the low 70 ppb range and 8-hour averages in the mid-60 ppb range.  While Thursday is expected to be similar, Friday has changes which create concerns for even higher ozone development. 

Of concern are lower wind speeds which will allow for stagnation rather than the well mixed atmosphere under the breezy conditions of the past few days.  This will affect SE Michigan the most.  Winds will become more southerly which will allow pollutants to stay out over Lake Michigan longer and have a better chance for additional photochemical reaction.  An afternoon lake breeze could bring those higher concentrations inland.  The other Lake Michigan states are also posting USG warning along the lake shore, as well.  In SE Michigan, the ozone plume will be pushed north of Detroit rather than to the east. 

As a result of these concern, Air Quality Advisories are being issued for the Lake Michigan shore from the Indiana boundary up to Leelanau County and the seven counties that make up SE Michigan.

The models are showing increasing clouds on Saturday which should make this a one-day event.  However, if the approaching system slows, Saturday may still be in play.  As such, the forecast will be updated Friday morning.

EXTENDED FORECAST:

Air Quality should be mostly Good begin the next work week.

Next Forecast update: Friday, April 14, 2023

04/12/2023 Forecast Update

FORECAST SUMMARY: Wednesday, April 12, 2023, through Thursday, April 13, 2023

OZONE: 8-hour average ozone concentrations are expected to be mostly Good to Moderate through the forecast period.

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

FORECAST DISCUSSION:

This has been an interesting week to track in terms of Air Quality.  We do not usually encounter ozone problems during April, especially the first half of April.  However, this week has proven to be an exception.

We have been seeing an increase in ozone production, each day, this week. Yesterday, we had some monitors in excess of 70 ppb for the 1-hour average.  What has saved us, so far, is the upper atmosphere is still cold, low dew points, limited daylight hours, and a brisk wind to keep the atmosphere well mixed.  If those factors were not in play, we would likely be looking at elevated ozone and be issuing Air Quality Advisories.

Thursday will most likely stay in the Moderate range for the reasons stated above.  However, Friday may be more challenging.  As the big, slow moving, high pressure system that has been giving us this great weather moves to the east, winds become a bit more southerly and not quite as strong.  Even with the early April limited hours of sunlight, skies will stay clear allowing maximum solar energy to get through.  Add the fact that each day has provided more ozone to the background to prime the next day’s ozone production.

As such, the forecast will be updated Thursday morning.  Friday should be the last day of concern as a low pressure system will approach on Saturday and move through the region during Sunday.

EXTENDED FORECAST:

Air Quality should be mostly Good begin the next work week.

Next Forecast update: Thursday, April 13, 2023

04/03/2023 Forecast Update

FORECAST SUMMARY: Monday April 3rd, 2023, through Monday April 10th, 2023

OZONE: Ozone concentrations look to remain Good for the forecast period.

PM-2.5: PM-2.5 concentrations are expected to range from Good to low-Moderate. 

FORECAST DISCUSSION:

For the lower peninsula of Michigan, it appears Spring has finally sprung with the majority of temperatures in the 50s and 60s for the foreseeable future. The upper peninsula will need a few more weeks to catch up as colder temperatures and lingering snowfall hangs around to the north.

For this week, multiple rounds of precipitation look to impact Michigan with some severity thrown into the mix on Tuesday and into Wednesday. A chance for thunderstorms is becoming more likely as model output is fine-tuned for midweek. The Low-pressure system and associated frontal boundary will exit the area on Thursday leaving breezy conditions in its wake for most of the day until a High-pressure system sets up just to our west on Friday. The weekend ahead looks to be dry and sunny with the help of the High-pressure lingering in the region. Sunday night into Monday brings the next chance of precipitation as another Low-pressure and cold front traverses the region with rain being the predominant precipitation type.

For air quality, it is still a little too early to notice any uptick in Ozone concentrations, but we are starting to look it at more so with temperatures rising and daylight lasting longer. For PM-2.5, the multiple rounds of precipitation and continuous breezy conditions will help keep concentrations at bay for the majority of the forecast period. With the High-pressure in place this weekend, concentrations may stick around, but should only be in the mid-Moderate range if that is the case. There may also be low-Moderate hourly concentrations most of the mornings this week per usual.

EXTENDED FORECAST:

Next week looks to continue the trend of precipitation with Monday looking to have rain in the forecast for the majority of the day. Overall air quality to start next week looks to remain Good.

Next Forecast update: Monday April 10th, 2023

3/27/2023 Forecast Update

FORECAST SUMMARY: Monday March 27th, 2023, through Monday April 3rd, 2023

PM-2.5:

PM-2.5 concentrations are expected to range from Good to low-Moderate. 

FORECAST DISCUSSION:

The month of March ends with temperatures nearing seasonal averages for most of Michigan with consistent seasonal norms as we get into April.

For this week, we start out today, Monday, with northerly flow providing cooler temperatures in the northern parts of the state. Winds shift throughout the day on Tuesday to more WSW with more chances of sunshine than today, Monday. A change in airmass comes through on Wednesday with a Low-pressure system and associated cold front. This will drop temperatures back below freezing for much of the state, but temperatures rebound on Thursday with a return to upper-30s and 40s. Southerly flow returns once the Low-pressure exits the area and gives way to High-pressure to our southeast. This lasts through Friday until a quick-hitting cold front comes through on Saturday providing mixed precipitation throughout the state and dropping temperatures slightly. This airmass sticks around through Sunday until a warm front appears to eclipse Michigan next Monday which may push some areas into the 60s.

For air quality, with the help of changing airmasses, PM-2.5 concentrations do not look like they will be a concern for this forecast period. Overall PM-2.5 concentrations will be Good with a chance of a few hours of Moderate in the morning hours of more populated areas.

EXTENDED FORECAST:

As stated above, a warm front appears to come through to start off next week. Overall air quality will remain Good.

Next Forecast update: Monday April 3rd, 2023

3/20/2023 Forecast Update

FORECAST SUMMARY: Monday, March 20, 2023, through Monday, March 27, 2023

PM-2.5:
24-hour average Fine Particulate concentrations are expected to be mostly Good through the forecast period.

FORECAST DISCUSSION:

Winter is hanging on as demonstrated by the past weekend.  Daytime high temperatures should be in the mid-40’s but we struggled to get much above the freezing mark during the weekend.  Snowfall amounts for the first half of March exceed the totals of January and February, combined.  While we should see some 50-degree weather during mid-week, we will not see a breakthrough warmup that we can call a Spring tease.

Air Quality is expected to be mostly Good though the forecast period.  Monday will start the week under sunny but windy skies.  The clear skies will give way, late Monday, as a cold front drops down from the north and stalls out across the middle of the Lower-Peninsula.  It will lift northward during Wednesday as a warm front.

A surface low will be approaching the state during Wednesday from the west and be over northern Indiana by Thursday morning and over Cleveland by Friday morning.  Some precipitation is expected from this system which should be mostly rain.

While the weekend forecast might be a bit premature, it does not appear too threatening with the occasional chance of rain or snow showers and seasonable temperatures.

EXTENDED FORECAST:

Air Quality should be mostly Good to begin the next work week.

Next Forecast update: Monday, March 27th, 2023

3/13/2023 Forecast Update

FORECAST SUMMARY: Monday, March 13, 2023, through Monday, March 20, 2023

PM-2.5:
PM-2.5 concentrations are expected to range from Good to low-Moderate. 

FORECAST DISCUSSION:

Winter’s grip continues to grasp onto Michigan to start off this week with many areas across the state seeing snow showers waking up this Monday morning. These snow showers should slowly dissipate as the day carries on leaving a few inches in their path. These snow showers are accompanied by northerly winds which will keep temperatures in the mid-20s to low-30s through Tuesday. A change in airmass comes Wednesday as winds shift to more southwesterly flow which will bump temperatures to the upper-30s and low-40s. This airmass lasts through Thursday until yet another system makes its way through the region on Friday. A Low-pressure system comes up from the southwest and will have a mixed batch of precipitation—rain, snow, and possible freezing rain. It is still too far out for true model agreement as models are nowhere near agreement on this system. The north or south trajectory will determine where the rain/snow line sets up, which will become more prominent as the week carries on. The system, as of right now, appears to somewhat stall over the region lasting through Saturday so additional precipitation may accrue due to that, along with winds staying relatively strong. As Sunday approaches, the system moves off to the east, shifting winds back to NNW and bringing colder temperatures back into the region.

In terms of air quality, northerly winds for a big portion of this week will keep PM-2.5 concentrations at bay. There may be low-mid Moderate concentrations in the morning hours but will dissipate as each day carries on. The end of the week system will clean out any buildup that occurs and will keep overall air quality Good for the weekend ahead.

EXTENDED FORECAST:

A slight warm up occurs on Monday which will possibly increase PM-2.5 concentrations to the Moderate range for a few hours, but overall air quality will remain Good to start off next week.

Next Forecast update: Monday, March 20th, 2023

3/6/2023 Forecast Update

FORECAST SUMMARY: Monday, March 6, 2023, through Monday, March 13, 2023

PM-2.5:
PM-2.5: 24-hour average Fine Particulate will range primarily Good with only small chances for low Moderate through the forecast period.

FORECAST DISCUSSION:

A low-pressure area tracking just south of the state Monday brings snow across central/northern locations and rain chances further south. High pressure then settles in producing dry and cool conditions for a few days. The next system brings mostly snow chances back in the forecast Friday while rain may mix in across southern areas.

As for air quality, Good to low-end Moderate fine particulate levels are anticipated Monday as the low passes to our south. The dominating weather feature then turns to high pressure positioned northwest/north of the state through midweek. Expect northerly winds and mostly Good fine particulate through Thursday. By Friday, easterly winds ahead of the next storm could allow for scattered low-Moderate fine particulate levels, otherwise, readings remain Good.

EXTENDED FORECAST:

Extended models show high pressure moving behind the Friday system with dry conditions Saturday into Sunday. Some models are showing the next weather feature bringing precipitation back late Sunday into Monday. Without a stagnant period or warm-up expected, fine particulate should remain mostly Good into early next week.

Next Forecast update: Monday, March 13th, 2023

2/27/2023 Forecast Update

FORECAST SUMMARY: Monday, February 27, 2023, through Monday, March 6, 2023

PM-2.5: 24-hour average Fine Particulate concentrations are expected to be mostly Good with occasional Low Moderate late in the weekend.

FORECAST DISCUSSION:

The forecast week start off messy with another winter system moving through the Midwest.  A warm front to the south causes warm, moist air to override colder Michigan air.  That scenario will yield rain in Southern Michigan, mixed precipitation in the middle, and snow to the north under easterly winds.  While messy, it should not last as long as last week’s winter storm and Air Quality is currently generally Good.

This system should be out of the picture early Tuesday replaced with westerly winds and continued Good Air Quality.  A weaker system is expected to move east into the area late Tuesday night bringing a light accumulation of rain in the south and snow in the middle and north.  Northeasterly winds will follow and more Good Air Quality.

The main event for the forecast period will come in the form of a strong system which will move into the area during Friday.  There is the potential for a significant snowstorm although the potential precipitation type and amount will be determined by the track of the storm.  Currently, the computer models are confining precipitation to the southern half of the state.

If any Low Moderates occur during this forecast period, it will likely occur later in the weekend when wind speeds are low and some stagnation could occur.  But for the most part, Good Air Quality will rule this forecast period.

EXTENDED FORECAST:

Air Quality should be mostly Good to begin the next work week.

Next Forecast update: Monday, March 6, 2023

2/21/2023 Forecast Update

FORECAST SUMMARY: Tuesday February 21st, 2023, through Monday February 27th, 2023

PM-2.5: PM-2.5 concentrations are expected to range from Good to low-Moderate. 

FORECAST DISCUSSION:

Unseasonably warm temperatures come to an end this week as a potential winter storm will impact all of Michigan Wednesday into Thursday. The most impactful timeframe will be Wednesday evening through Thursday morning with more ice potential in the southern portions of the state and upwards of 6-10+ inches of snow possible for northern portions of Michigan. This system exits the area Thursday afternoon and leaves a swath of mixed precipitation and temperatures ranging the from upper teens to low 30s depending on the north or south location in Michigan. Accompanying this storm are strong winds with wind gusts upwards of 35 mph predominantly from the northeast. Going into the weekend, High-pressure sets up to our west and then to our east as the weekend carries on. Temperatures hover around the upper-20s and low-30s with shifting south to southwesterly winds. Monday sees a slight warmup with the majority of Michigan above the freezing mark with the help of southeast winds.

In term of air quality, ample winds to start off this week has helped to keep PM2.5 concentrations at bay and in the Good to low-Moderate category. The impending system mid-week will help keep the concentrations at bay even more so, especially with the increase in winds. As winds subside going into the weekend, PM2.5 concentrations will have the chance to increase but a cooler atmosphere will help keep concentrations lower as warmer temperatures and melting of snow does not look to happen until early next week.

EXTENDED FORECAST:

After a slight warmup on Monday, temperatures return to seasonal norms as a frontal boundary comes through early Tuesday morning. Overall air quality will remain Good.

Next Forecast update: Monday February 21st, 2023

2/17/2023 Forecast Update

FORECAST SUMMARY: Friday, February 17, 2023, through Tuesday, February 21, 2023

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

FORECAST DISCUSSION:

The forecast period begins with Good fine particulate thanks to northerly winds behind the Thursday storm which brought snow across much of the state and also mixed precipitation further south. High pressure will be the dominating weather feature early in the Presidents Day weekend. Cold conditions Friday moderate by Saturday as the high tracks east of the state.

As for air quality, northerly winds Friday switch more southwesterly Saturday. With warmer air moving over the recent snow, we can expect an associated increase in fine particulate levels. Fine particulate should be in the upper Good to middle Moderate range. A weak clipper system tracks north of the state Sunday bringing snow chances further north, but winds should be strong enough to hamper a significant increase in pollution levels. Winds shift northerly for a short time late Sunday/early Monday before decreasing in speed between two weather systems. Since this will not be a prolonged stagnant weather pattern, daily averages of fine particulate should remain in the upper Good to middle Moderate range early next week.

EXTENDED FORECAST:

Extended models show a weaker system passing to the north Tuesday, then a more active period later in the week. If the timing of the Tuesday system remains on track, chances for snow make a return across the northern portion of the region and a wind shift to the northwest should improve any possible fine particulate buildup. Regardless on how the timing of that system pans out, fine particulate is not expected to reach higher than Moderate towards the end of the forecast period.

Next Forecast update: Tuesday, February 21, 2023

Stephanie M. Hengesbach

2/13/2023 Forecast Update

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

PM-2.5: 24-hour average Fine Particulate will be Good to Moderate through the forecast period.

FORECAST DISCUSSION:

The week begins on a quiet note with dry conditions Monday into Tuesday, then a more active pattern develops. By Tuesday, northerly winds turn southerly ahead of an approaching storm system. The change in direction increases both temperatures and moisture. Associated precipitation holds off until later Tuesday and precipitation should generally be in the form of rain. Warmer temperatures linger Wednesday as the state becomes positioned between two systems. The next storm brings mixed precipitation Thursday. Models show conditions drying out Friday with only some lake effect snow lingering.

As for air quality, northerly winds Monday should keep fine particulate mostly Good. As southerly winds develop Tuesday and moisture moves into the region, levels increase to a mix of upper Good to middle Moderate. This range continues Wednesday into Thursday, but readings improve Friday as northerly winds move in behind the Thursday storm system.

EXTENDED FORECAST:

Extended models show high pressure dominating during the weekend as temperatures warm back into the 40s. Breeze conditions are also expected, and it does not look like long range fine particulate will be a concern but with the Presidents Day holiday next Monday, we will do a forecast update Friday to detail levels through next Tuesday.

Next Forecast update: Friday, February 17, 2023

Stephanie M. Hengesbach

2/6/2023 Forecast Update

FORECAST SUMMARY: Monday, February 6th, 2023, through Monday, February 13th, 2023

PM-2.5:
24-hour average Fine Particulate concentrations are expected to be mostly Good with occasional Low Moderate during mid-week.

FORECAST DISCUSSION:

High pressure over the upper Midwest will slide eastward during Monday with Air Quality mostly Good.  In its wake, a cold front will advance with strong southerly winds and warming temperatures for late Monday night and early Tuesday.  That front is projected to pass through Michigan during the day Tuesday. 

 High pressure will return for the remainder of Tuesday and Wednesday.  The best chance for any Low Moderate conditions, during the forecast period, would likely be Wednesday with light southerly winds allowing a buildup of fine particulates.

 A stronger low pressure system invades the area during early Thursday providing a decent amount of mixed precipitation.  As that system exits the area late Thursday, winds will shift to the northwest and any residual fine particulates should be cleaned out returning the state to the Good category.

 Winds are expected to return to a southerly flow during Sunday and Monday.  Winds speeds are expected to be fairly brisk and should keep the atmosphere well mixed.  Most of the state is expected to have Good Air Quality but the occasional Low Moderate could sneak in.

EXTENDED FORECAST:

Air Quality should be mostly Good to begin the next work week.

Next Forecast update: Monday, February 13th, 2023