04/08/2024 Forecast Update

FORECAST SUMMARY: Monday, April 8, 2024, through friday, April 12, 2024

OZONE: 8-hour average Ozone concentrations will be Good (AQI Green).

 PM-2.5:  24-hour average Fine Particulate concentrations are expected to remain generally Good (AQI Green).

FORECAST DISCUSSION:

Eyes will be cast skyward, today, but not for weather or Air Quality, but a rare near-total eclipse in southern Michigan.  In the Lansing area, maximum 96% coverage is expected around 3:12 PM under mostly clear skies for prime viewing.  As a bonus, Air Quality is expected to remain Good.

 A cold front will pass, during Tuesday, with little notice other than an occasional shower and a few degrees cooler. 

 The main weather feature for the week will be another cold front passing during Thursday.  This system looks to be a real soaker with the potential of over an inch of rain in most areas with some areas potentially getting near two inches.

 Throughout the week, I am expecting Air Quality to remain Good.

 EXTENDED FORECAST:

 Air Quality should be generally Good to begin the weekend.

Next forecast update: Friday, April 12, 2024

04/05/2024 Forecast Update

FORECAST SUMMARY: Friday, April 5, 2024, through monday, April 8, 2024

Ozone: 8-hour average Ozone concentrations in the Good range are expected through the forecast period.

 PM-2.5: 24-hour daily average Fine Particulate concentrations are expected to average Good with Moderate readings possible early next week.

 FORECAST DISCUSSION:

 Conditions dry out Friday as the storm system, which brought snow north and rain south, moves off the east coast and high pressure moves in from the west. High pressure continues to dominate our weather on Saturday, but on Sunday, a warm front associated with a low-pressure area to our southwest pulls north, bringing precipitation back into the forecast. Winds switching to a southerly component also bring in warmer air, with mild conditions anticipated early next week.

 There is a lot of weather interest on Monday because of the solar eclipse. The path for viewing the eclipse ranges from greater than 90% in extreme southeast Michigan to between 70% and 80% in the western Upper Peninsula. Current forecast models show some hope of viewing based on anticipated cloud cover. The forementioned low-pressure area tracks from southwest Minnesota on Sunday afternoon to the western Great Lakes region on Monday. Models are picking up on dry air wrapping in the central and southern parts of the state Monday afternoon. While precipitation chances are not zero during this period, they are low, and the drying could decrease clouds enough to allow viewing of the eclipse. Just remember, protective eyewear is necessary when looking directly at the eclipse, so precautions should be taken.

 As for air quality this forecast period, northeasterly winds will keep both ozone and PM2.5 in the Good range through Saturday. Ozone readings will remain Good through the period; however, southerly winds and increased moisture Sunday into Monday may allow for increases in PM2.5 into the low Moderate range.

 EXTENDED FORECAST:

 Extended forecast models show mild conditions continuing towards mid-week, with precipitation chances lingering into Tuesday. Pollution levels will likely range from Good to low-Moderate during that period.

Next Forecast Update: Monday, April 8, 2024

04/01/2024 Forecast Update

FORECAST SUMMARY: Monday, April 1, 2024, through Friday, April 5, 2024

Ozone: 8-hour average Ozone concentrations in the Good range are expected through the forecast period.

 PM-2.5: 24-hour daily average Fine Particulate concentrations are expected to be mostly Good with only small chances for low-Moderate readings.

 FORECAST DISCUSSION:

 With today, Monday, being the start of April, we will officially begin forecasting ozone for the 2024 season. High pressure dominates weather conditions most of Monday before precipitation moves in ahead of a low-pressure area that sets up over the region through mid-week. This system will produce unsettled conditions with rain showers in the forecast starting Monday afternoon or evening across southern locations; precipitation further north holds off until Tuesday. As temperatures fall Tuesday, precipitation may mix with or change over to snow, especially in northern areas. The slow-moving storm finally moves east of the region on Thursday, drying conditions out for the end of the week. Cooler temperatures are in the forecast this week, with readings improving as we move into the coming weekend.

 As for air quality, pollution levels are starting the period in the Good range and ozone levels through the forecast period will remain Good. Wind speeds, especially in the southeastern portion of the state, may decrease for a time Wednesday as the storm positions itself overhead. Fine particulate levels in the low-Moderate range may be a possibility during this period, however, most locations will remain Good. Any increases in fine particulate improve Thursday as northwest winds develop behind the departing systems. 

 EXTENDED FORECAST:

 Extended forecast models show dry conditions as high pressure moves in from the west. The extended period should begin with Good air quality, but, low Moderate fine particulate readings may develop late in the period as winds decrease and warmer air moves in.

Next Forecast, April 5, 2024

03/29/2024 Forecast Update

FORECAST SUMMARY: Friday, March 29th, through Monday April 1st, 2024

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

FORECAST DISCUSSION:

As we near the end the month of March, today, Friday, will be the nicest day we have had in a little over a week. The majority of Michigan will see surface temperatures in and around the 50s with ample sunshine due to a High-pressure system directly over the southern half of the state. Throughout the day today, this High-pressure will drift off to the northeast which will make way for a Low-pressure system, associated with a frontal boundary and mixed precipitation. Friday night into Saturday morning will see predominantly rain for the lower peninsula and mixed precipitation for the upper peninsula. Precipitation will be consistent during the early morning hours and turn more scattered as the day, Saturday, carries on. Once the Low-pressure moves off to the east, Sunday will see Michigan in between two pressure systems with a High-pressure to the north and a Low-pressure to the south. This will cause Easter Sunday to be relatively dry, with temperatures near the 50s, yet cloudy. The clouds stick around for the start of April on Monday, with some spotty rain showers for scattered areas across Michigan.

Due to the shifting airmasses this weekend, PM-2.5 concentrations will not be able to stagnate and increase, so overall concentrations will be in the Good range.

EXTENDED FORECAST:

Next week starts off the same way the weekend ends—cloudy. A few more systems roll through next week with spotty showers as well, so overall air quality will remain Good.

Next Forecast, April 1, 2024

03/25/2024 Forecast Update

FORECAST SUMMARY: Monday, March 25th, 2024, through friday, March 29th, 2024

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

FORECAST DISCUSSION:

After last week’s early Spring snowfall for the majority of the state, we bounce back with above normal temperatures for much of this week with some dips down to near-normal temperatures. This week will also have a mixed bag of sunny, clear days and rainy, cloudy days.

Today, Monday, will see one of those aforementioned above-normal days for much of the lower peninsula with the western end of the upper peninsula near normal temperatures for this time of the year with additional snowfall in the forecast. Monday night into Tuesday will see a Low-pressure system and associated frontal boundary traverse the state, bringing rain for the majority of the state and some snow showers for the upper peninsula. As we head into the middle part of the week, temperatures, statewide, slide into the upper 30s to mid-40s with sunshine returning more prominently compared to the beginning part of the week. We end the work week on a high note with temperatures in the low-to-mid-50s all around and ample sunlight.

For air quality, accompanying the warmer temperatures today and tomorrow will be breezy conditions as the Low-pressure system crosses the state. A combination of the rain and breezy conditions will help to keep PM-2.5 concentrations in check for the beginning half of the week. As the skies clear midweek and winds lessen, there is a chance for PM-2.5 concentrations to increase into the Moderate range during the morning hours, then slowly dissipating to Good for the remainder of the day. Because of the increase and decrease in concentrations I am putting forth a Good to low-Moderate forecast for PM-2.5. We are nearly to the point in the year where we bring back our Ozone forecast, which will be included in the next week’s forecast and going forward.

EXTENDED FORECAST:

Another system is looking to clip the state Friday into Saturday, which will keep our air quality in the Good range.

Next Forecast, March 29, 2024

03/22/2024 Forecast Update

FORECAST SUMMARY: Friday, March 22, 2024, through Monday, March 25, 2024

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

FORECAST DISCUSSION: Friday greets us with (hopefully) the last snowstorm of the season.  Snowfall is widespread across central and lower Michigan with several inches expected throughout the day.  Air Quality is expected to remain Good during this snow event.

 High pressure moves in during Saturday with low temperatures, Saturday night, expected to be very cold with overnight temperatures dipping into the teen’s.

 I expect a warmup by Monday as the high pressure ridge slides to the east and the next storm system approaches from the west.  All of the Air Quality models are showing Good through the weekend, and I do not see anything that makes me think otherwise.  Melting snow under warming temperatures can lead to some Moderate conditions but breezy conditions during Monday should keep that in check.

 EXTENDED FORECAST:

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

Next Forecast, March 25, 2024

03/18/2024 Forecast Update

FORECAST SUMMARY: Monday, March 18, 2024, through Friday, March 22, 2024

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

FORECAST DISCUSSION: St. Patrick’s Day weekend was generally awash with the color green.  However, as we greet this Monday morning, many areas are greeted with yet another dusting of snow.  On the other hand, the vernal equinox, which marks the start of the astronomical season of Spring, occurs this Tuesday, March 19, at 11:06 p.m. ET.  This is good news for us who yearn for the warmer seasons.  The other good news is Air Quality is Good from coast-to-coast and border-to border.  Rarely do we see it when the green AQI covers the whole country with no exceptions.

Our current cooler weather can be attributed to a high pressure ridge in the central plains which is driving our winds from the northwest.  An approaching clipper system, during Tuesday, will push those winds down to more of a westerly direction and allow for some warming into the 40’s.  As that clipper passes to our north late Tuesday, it will drag a cold front through the area and keep Wednesday’s temperatures in the low 30’s back under more northwesterly winds.

 High pressure on Thursday will give us our only sunny skies for the work week.  Winds will diminish and the best chance for any Low Moderates could occur in the more urban areas due to stagnation.  Another wave of low pressure looks to pass through the Great Lakes late Thursday through Friday with the possibility of another shot of snow showers before a gradual warming cycle through the weekend.

 EXTENDED FORECAST:

Air Quality should be generally Good to begin the weekend.

Next Forecast, March 22, 2024

03/15/2024 Forecast Update

FORECAST SUMMARY: Monday, March 15, 2024, through Friday, March 18, 2024

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

FORECAST DISCUSSION: This forecast period starts with dry weather and mild temperatures. A more unsettled pattern develops by Saturday, however, due to a storm system tracking across the northern Great Lakes region. An associated cold front will move from northwest to southeast during the day on Saturday. Precipitation further north may start as rain but transitions to snow as cold air moves in. Less precipitation is expected across the southern portion of the state. Cooler air filters in statewide late in the weekend, which kicks in lake effect snows for the most prone north-to-northwest wind flow locations. Cold air is reinforced Monday as another boundary drops in from the north. Cooler temperatures linger until mid-week next week.

 As for air quality, weak northerly winds are aiding in Good readings statewide Friday morning. Winds will switch to a southwesterly direction for a short time ahead of the Saturday system, but past that, gusty winds Saturday and cooler air coming in on a northerly flow both Sunday and Monday will keep fine particulate levels in the Good range.

 EXTENDED FORECAST:

Extended forecast models show below normal temperatures continuing towards mid-week. Mostly Good fine particulate levels are expected during this period.

Next Forecast, March 18, 2024

03/11/2024 Forecast Update

FORECAST SUMMARY: Monday, March 11, 2024, through Friday, March 15, 2024

PM-2.5: 24-hour daily average Fine Particulate concentrations are expected to range between Good and low Moderate through the forecast period.

FORECAST DISCUSSION: After a cool weekend with Good air quality, temperatures warm up through mid-week thanks to high pressure positioned south of the state and a warm front lifting into the northern portion of the Great Lakes region. Southwesterly winds develop Monday into Tuesday, ushering in warmer air. The forementioned boundary sinks south, becoming positioned between the central and southern portions of the state on Wednesday. Precipitation comes into the forecast starting Wednesday, but by Thursday, a low-pressure area moves in along this boundary from the southwest, enhancing precipitation. During this period, more widespread showers, along with some storms, can be expected. Northeasterly winds develop Friday as the low pulls away, bringing cooler temperatures back over the region.

 As for air quality, above normal temperatures on a southerly wind may allow for fine particulate to increase into the Moderate range through Thursday; therefore, a mix of upper Good to low-Moderate concentrations is expected statewide. Smoke plume forecast maps were evaluated and show a light plume coming up from the southern Plain states on Tuesday; however, at this time, the plume does not appear to influence fine particulate concentration. The cooler northerly flow will bring levels back to the Good range on Friday.

 While we are not officially forecasting for ozone this early in the season, it's worth mentioning that depending on the amount of sunshine Tuesday and Wednesday, the warmer temperatures on the southwesterly wind may also allow for some low-Moderate 8-hour ozone concentrations; however, this would be isolated, and most locations will remain Good.

EXTENDED FORECAST:

Extended forecast models show dry conditions for late in the week, but another storm system is dropping in from the northwest towards the end of the weekend. Mostly Good fine particulate levels are expected during this period.

Next Forecast, March 15, 2024

03/08/2024 Forecast Update

FORECAST SUMMARY:friday, March 8, 2024 through March 11, 2024

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

FORECAST DISCUSSION: After yet another week of rollercoaster-like temperatures, Michigan returns to somewhat seasonal norms this weekend after a cold-front treks through the region. Associated with this cold front is rain for the southern portions of the state, snow showers for the northern portions, and a wintry mix for those in between. The precipitation will start from the southwest later this morning and move to the northwest throughout the day and into the overnight. Most of us wake up tomorrow, Saturday, with lingering showers, but Saturday will be predominantly dry with breezy northwest winds in place and surface temperatures in the upper-20s to mid-30s. Sunday is almost identical to Saturday but with more sunshine in place, although we stay near seasonal norms for temperatures in the 30s. Monday is the start for a weather turnaround with winds shifting to the southwest which will bring in warmer air, and thanks to a High-pressure to the southeast, sunshine becomes more prominent. 

Due to the near day-long rain today, Friday, and breezy conditions on both Saturday and Sunday, PM-2.5 concentrations will not be an issue and will stay in the Good range. As we start off next week, surface temperatures climb and winds shift, so PM-2.5 concentrations will start to uptick, but should still stay in the Good range on Monday.

EXTENDED FORECAST:

A warmup is on the horizon for next week thanks to a High-pressure system. Air quality will be in the Good to low-Moderate range due to rising temperatures and light winds.

Next Forecast, March 11, 2024

03/04/2024 Forecast Update

FORECAST SUMMARY:monday, March 4, 2024 through March 8, 2024

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

FORECAST DISCUSSION: The start of the first week of March feels more so like the end of May as surface temperatures range from the upper-50s to low-70s across Michigan today, Monday. These warm temperatures are short-lived as a Low-pressure system and associated cold front moves through Tuesday throughout the day bringing rain for southern Michigan and a wintry mix for northern Michigan. The pressure system switches the winds to more northerly for midweek on Wednesday, so surface temperatures hang around the 30s to 40s with some breezy conditions in place. Warmer temperatures look to return on Thursday with the help of southerly flow with surface temperatures in the upper-40s to low-50s. Yet another system comes through on Friday and into Saturday which will bring more mixed precipitation and drop temperatures back into seasonal norms.

For air quality, today, Monday will see the highest chance of Moderate PM-2.5 concentrations throughout the state due to southerly flow and warmer temperatures. As the system rolls through on Tuesday, breezy conditions will help clean out the airmass and the wind direction switch to the north will help keep the airmass clean. Midweek, as winds switch back to southerly, PM-2.5 concentrations may increase in the urban areas, but nothing too alarming. The system on Friday and Saturday will help clean out the airmass once again and provide us Good air quality to start off the weekend.

As Jim stated on last week’s forecast update, it is now officially Ozone season. However, we will not start forecasting Ozone until April 1st as the overall environment is not yet conducive for Ozone development.

 Officially, ozone season begins today (March 1) in terms of monitoring.  Similar to previous years, our forecast season for ozone will begin on April 1 as our cooler weather and shorter days keeps ozone risk at a minimum during March.

EXTENDED FORECAST:

As stated above, we start off the weekend with Good air quality thanks to a Low-pressure system which will drop temperatures back into seasonal norms. These temperatures will also carry into early next week.

Next Forecast, March 8, 2024

03/01/2024 Forecast Update

FORECAST SUMMARY: Friday, march 1, 2024, through monday, March 4, 2024

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

FORECAST DISCUSSION: In like a lamb, out like a lion?  Or so goes the saying for March weather…  If the proverb is correct, the beginning of March 2024 will be more akin to “lamb” weather with mostly sunny skies and gradually warming temperatures.

 Following the sharp 50 degree drop in temperatures we experienced during mid-week, we can expect a gradually warming trend over the upcoming weekend.  We are in a persistent southerly wind flow sector which could get us back to near 70-degree temperatures by Monday.  This is due to a large high-pressure ridge over the east coast and approach low-pressure system to our west.  As such, we should see mostly clear skies through the weekend and each day warming by several degrees.  I expect this to last until the next projected cold front passage during Tuesday.

 In terms of Air Quality, all the models are in agreement that conditions should stay mostly in the Good range with a chance for a few scattered Low Moderates in the more populated areas.  Fortunately, the smoke from the historically large Texas panhandle fires should stay to the west and have little to no effect on us.

 Officially, ozone season begins today (March 1) in terms of monitoring.  Similar to previous years, our forecast season for ozone will begin on April 1 as our cooler weather and shorter days keeps ozone risk at a minimum during March.

EXTENDED FORECAST:

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

Next Forecast, March 4, 2024

2/26/2024 Forecast Update

FORECAST SUMMARY: Monday, February 26, 2024, through Friday, March 1, 2024

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

FORECAST DISCUSSION: The early part of the week will pretend like its mid-April with warm temperatures and the threat of severe weather.  The National Weather Service has issued a hazardous weather outlook for Monday night in the southwest corner of the state.  Strong southwesterly air flow and warming temperatures will continue Tuesday and confidence is high we will see thunderstorms develop through the day.  Confidence is increasing that a few of the storms may be strong to severe through Tuesday night.

Following this shot of Spring weather will be a cold front which will turn the weather sharply colder for the Wednesday morning commute.  Snow showers and some light accumulations could affect the morning drive to work.

Air Quality is expected to be mostly Good as the atmosphere goes through this turbulent period.  As winds turn northwest following the frontal passage, the air should also be very clean and Good conditions persist.  Winds return to the southwest Thursday afternoon for another warmup for the weekend.  The air should still be clean and Air Quality remaining Good.

EXTENDED FORECAST:

Air Quality should be generally Good to begin the weekend.

Next Forecast Update: Friday, March 1st, 2024

2/23/2024 Forecast Update

FORECAST SUMMARY: Friday, February 23, 2024, through monday, February 26, 2024

PM-2.5: 24-hour daily average Fine Particulate concentrations are expected to range between Good and low Moderate through the forecast period.

FORECAST DISCUSSION: Fine particulate levels on Thursday were running high across the southern half of lower Michigan thanks to an inversion that lingered through the day, causing pollution to increase at ground level. Hourly fine particulate readings reached the USG range for a portion of the day; however, only one monitor ended up reaching low-end USG for the daily average; most other sites ended the day in the middle to upper Moderate range. Pollution levels are improving today, Friday, thanks to a frontal boundary dropping in. This front will bring in cooler temperatures for the end of the week, along with small chances for snow showers. This cooldown will be short-lived, as a warmup is already anticipated for Sunday.

Hourly readings of fine particulate Friday morning range from Good further north to Moderate in southern locations. As the front passes during the day, winds pick up from the northeast, which will bring hourly concentrations back into the Good range statewide. Daily averages of fine particulate are expected to be mostly Good Friday, aside from a possible low-Moderate lingering in the southeast.

Cooler temperatures move over the state Friday and Saturday as surface high pressure moves in behind the cold front. Temperatures will fall during the day on Friday, and highs on Saturday will be below normal for this time of year. Weaker winds will be in place Saturday as the high slides overhead, but fine particulate should remain mostly Good for the day. Stronger southerly winds develop on Sunday, rebounding temperatures from the cool Saturday. Wind speeds should be strong enough to keep the atmosphere well-mixed, allowing for a continuation of mostly Good fine particulate levels.

EXTENDED FORECAST: Extended forecast models show a weak system passing northeast of the state late Sunday, decreasing wind speeds for a time early Monday. Stronger southwest winds move in quickly behind it, and a warmup is still in the forecast for early to mid-week. Without a stagnant period anticipated in the long term, pollution levels into next week should remain in the Good to low Moderate range.

Next Forecast Update: Monday, February 26th, 2024

2/20/2024 Forecast Update

FORECAST SUMMARY: Tuesday, February 20, 2024, through Friday, February 23rd, 2024

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

FORECAST DISCUSSION: Mild conditions persist through mid-week, with generally sunny skies on Tuesday turning a bit cloudier on Wednesday and Thursday. A weak system over the region may produce some light precipitation on Wednesday, but most areas remain dry. On Thursday, a storm system tracks from west to east through the Ohio River Valley. Precipitation from the system may reach portions of the state, but a more noticeable change in conditions comes Friday as an arctic cold front drops in from the north, bringing colder temperatures and lake-effect snow back into the forecast.

Fine particulate levels Tuesday morning have been running from middle to upper Moderate across the central and southern portions of the state. Hourly concentrations should improve as the day progresses; however, daily averages in the Moderate range are expected across most of the lower peninsula. On Wednesday, southerly winds pick up and warmer air moving in will help dissipate some of the snowpack that still exists. The increase in moisture will keep daily averages of fine particulate mostly Moderate statewide, and like Tuesday morning, a few morning hourly readings may be in the high Moderate to low-end USG range before falling to middle Moderate late morning. Moderate concentrations may linger into Thursday as well, but the cold front dropping in from the northwest on Friday will improve any buildup and bring back Good pollution levels for the end of the week.

EXTENDED FORECAST: Extended forecast models show the cooldown being short-lived, with another warm-up for next week. Weekend fine particulate levels should remain mostly Good but could increase towards Moderate again if the warmup pans out.

Next Forecast Update: Friday, February 23rd, 2024

2/16/2024 Forecast Update

FORECAST SUMMARY: Friday, February 16, 2024, through Tuesday, February 20th, 2024

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

FORECAST DISCUSSION: A return to winter was felt in the latter half of this week with essentially all of Michigan receiving some form of wintry precipitation. Along with a return of snow, temperatures dropped to near-normal temperatures and will be below normal as we start off our weekend on Saturday with highs ranging in the 20s. NNE winds will be dominating the region this weekend and is the culprit for the below-normal temperatures. Due to the cooler temperatures and NNE winds, lake-effect snow will be present throughout the weekend, especially for communities along Lake Superior and in the northwestern Lower Peninsula. Although winds stay relatively the same directionally, upper-level patterns bring slightly warmer air back to Michigan on Sunday with temperatures in the low-mid 30s. A reversal of the winds occurs on Monday as a pressure system moves into the region from out west, which will bring warmer southwesterly winds. This will continue into early next week as yet another warmup is on the horizon.

For air quality, due to the predominantly northerly winds for the majority of the weekend, PM-2.5 concentrations will not be an issue as cleaner air will be regularly blown into the region. Conditions will also be breezy at times so the odds of long-lasting inversions are low. In the latter half of the weekend and going into next week, warmer temperatures and change in air direction will allow for some particulates to increase, hence why I have a Good to low-Moderate range for the PM-2.5 forecast.

EXTENDED FORECAST: As stated above, a warmup is on the horizon for the middle of next week with the 50s returning to the area. Increases in surface temperatures and a disjointed snowpack across the state may allow for PM-2.5 concentrations to approach the mid-to-high Moderate range.

Next Forecast Update: Monday, February 20th, 2024

2/13/2024 Forecast Update

FORECAST SUMMARY: Tuesday, February 13, 2024, through friday, February 16, 2024

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

FORECAST DISCUSSION: Seasonal normal temperatures have returned to the Great Lakes with upper-20 to mid-30s expected throughout this week. Although temperatures have decreased from last week’s record high temperatures, the sun will be more present this week than it was for the majority of January. Today, Tuesday, and Wednesday will have High-pressure in place which will provide ample sunlight. These High-pressure systems remain in place until Thursday morning when a Low-pressure system treks through the region from the southwest. Accompanying the Low-pressure will be an associated cold front and moisture from the south which will aid in producing snowfall for much of Michigan. North of the I-69 corridor will have the highest snowfall amounts with expected snowfall accumulation in the three-to-five-inch range with some higher accumulations locally. This system will be rather quick-moving, so snowfall will mainly take place during the day on Thursday and the entire system will be over the east coast by Friday morning. Friday will have leftover snowfall with less accumulation for the interior areas, and lake-effect snow for shoreline communities.

For PM-2.5, with the current High-pressure regime, expect Moderate PM-2.5 concentrations in the morning hours when winds are light and atmospheric inversions are possible. The atmospheric inversions should dissipate throughout the day, allowing for the dispersion of pollutants being trapped near the surface. During these inversions, and morning commutes, it is possible for PM-2.5 concentrations to eclipse the Unhealthy for Sensitive Groups threshold for an hour or two. Moderate is forecasted, however, due to the expected 24-hour average being in the Good to Moderate range. Due to the system coming through on Thursday, any buildup of concentrations will be cleaned out, moving us back into a consistent Good-range regime.

EXTENDED FORECAST: Cooler temperatures are expected this weekend with surface highs in the 20s. Northerly winds will help in providing us Good air quality into the next week.

Next Forecast Update: Friday January 16th, 2024

2/9/2024 Forecast Update

FORECAST SUMMARY: Friday, February 9, 2024, through Tuesday, February 13, 2024

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

FORECAST DISCUSSION: After a night where thunder was heard in many areas, Friday will be the last day of near record high temperatures for this time of year.  We are expecting clear skies with downstate temperatures in the mid-50’s.  Much of this can be contributed to being in the warm air advection sector of an advancing frontal system. 

While we have seen mostly Moderate conditions during the week, it will be cleaned out Friday with increasing winds, shifting winds and cooling temperatures in time for the weekend.  As the winds become more northwesterly during Saturday, daily high temperatures will drop into the 30’s and low 40’s, which is still a bit above normal for this time of year.

Air Quality will remain Good through the weekend and the beginning of the next work week.  Due to scheduling, the next scheduled forecast call and update will be Tuesday.

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

Next Forecast Update: Tuesday, February 13, 2024

2/5/2024 Forecast Update

FORECAST SUMMARY: Monday, February 5th, 2024, through Friday, February 9th, 2024

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

FORECAST DISCUSSION: High pressure continues to dominate the region bringing much appreciated clear skies and sunshine to the state.  In addition, we are looking at a gradual warmup during the week with potentially record high temperatures near 60 by Thursday. 

The warming temperatures, calm winds and ample moisture also bring the possibility of increasing fine particulates.  Clear skies at night have the tendency to create an inversion trapping air near the ground.  With the morning rush hour occurring at the same time, we usually see a spike in morning particulate concentrations in the more urban areas.  During the summer, the strong daytime sun will break up that inversion allowing vertical dispersion and dilution of surface pollutants.  However, with the weaker winter sun, the inversion stands a better chance of staying intact during the day keeping those pollutants trapped near the surface.

We saw that Sunday with higher PM-2.5 values in the 20-30 ug/m3 range, especially in Southeast Detroit.  That trend will likely continue through the week with the warming temperatures and the forecast models are also indicating that trend.

As such, I will be forecasting increasing Moderate through much of the state with particulates accumulating due to no change in air mass.  While I currently have no strong reason to think it will be any worse than Moderate, I will be keeping an eye on our monitors and will update this forecast if any areas look to trend into the USG range.  Otherwise, this forecast will be updated on Friday for the normal weekend forecast.

EXTENDED FORECAST: Air Quality should be generally Moderate trending back to Good beginning the weekend.

Next Forecast Update: Friday, February 9th, 2024

2/2/2024 Forecast Update

FORECAST SUMMARY: Friday, February 2nd, 2024, through Monday February 5th, 2024

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

FORECAST DISCUSSION: One month down already in 2024 as February starts off with Spring-like temperatures and relatively sunny conditions. After a week of somewhat cloudy and foggy conditions, a High-pressure system lingers in the Great Lakes region for the length of the weekend ahead which will provide clear conditions. Surface temperatures throughout the weekend will range from the low-40s to mid-40s, but with the sun shining, it may feel a tad warmer. Wind direction will be shifting all weekend due to the High-pressure system moving around the Great Lakes. Although winds on Sunday will be northerly, surface temperatures will still be in the 40s due to upper-level patterns bringing warmer air to the area. These northerly winds will carry into Monday with the start of next week looking almost identical to Sunday in terms of sunshine and warmer surface temperatures.

In terms of air quality, PM-2.5 will start off in the Good range and slowly approach the low-Moderate range as the weekend comes to a close. With the High-pressure in place, winds will be light and will allow for particulates to hang around longer before dispersing. The morning hours, especially, will see more Moderate concentrations in the more populated areas, but winds, although light, will pick up throughout the day and help to clean out the airmass.

EXTENDED FORECAST:

The warm temperatures this weekend carry into the next week with some areas in the 50s towards the latter half of the week. High-pressure slowly moves off to the east, so winds will continue to be light which will allow for some Moderate PM-2.5 concentrations. Overall air quality will range from Good to Moderate into the next week.

Next Forecast Update: Monday, February 5th, 2024