Monday, March 18, 2024 3:05 AM
Prepared by Bob Weisman, SCSU Meteorologist and Professor Emeritus
Coolest of March This Weekend
After the bulk of March so far has been much milder than average (12 of 17 days at least 10 degrees milder than average; see NWS St. Cloud March 2024 high-low temperature table), yesterday marked the first colder than average day since the two cold days we had at the end of February (see 30-day graph of St. Cloud temperatures from MesoWest). The cold came in during the early morning hours of Saturday, but the Friday night midnight temperature was 51 degrees, marking the Saturday high. Still, temperatures only held in the lower 40's during Saturday. Yesterday, the temperature merely rose to 31 degrees, the only colder than average high in March so far (below the green-pink changeover on the NWS St. Cloud March 2024 high-low temperature graph). Temperatures early this morning were headed for the teens (see NWS Aviation Weather Center METAR map) for the first time in a week.
Some Flakes in the Air, With More on the Ground Along South Shore of Lake Superior
As the cold upper-air low has pushed into Michigan (see Mid-tropospheric water vapor loop from Colorado State satellite slider), the cold air aloft and the fairly mild ground have led to a number of snow showers (see spotty echoes on the College of DuPage north central US radar loop and radar patches on the NWS Aviation Weather Center METAR map). The radar is patchy because the clouds producing this snow are fairly low in the atmosphere (white on the Shortwave Albedo satellite loop from Colorado State satellite slider). Those snow showers have merely produced flurries in the bulk of Minnesota, but where extra instability exists as the cold air moves over the relatively warm lake water, there have been 3-9 inches of snow along the Upper Peninsula of Michigan with lighter amounts in northern Wisconsin. Upwind of Lake Superior, there have been some spotty light accumulations in northeastern Minnesota.
Blustery All Weekend
In addition, the pressure difference between the Great Lakes low and the cold high moving out of north central Canada (see 4 PM Saturday NWS WPC North America surface map) created the very strong winds that have accompanied the colder temperatures. Those winds gusted as high as 43 MPH in St. Cloud on Saturday afternoon and over 30 MPH yesterday (see NWS: last 72 hours of St. Cloud observations). It isn't quite as windy now, but there are still gusts to nearly 20 MPH (see NWS Minnesota hourly weather round-up), producing wind chills in the plus single digits from St. Cloud westward.
Colder Than Average Will Return Tuesday Through Rest of Week
This week will be a major change from the dominant weather pattern we've seen for most of the cold season. We are firmly in the grip of the northern branch of the upper-level steering winds. They are moving distinctly northwest-to-southeast across northern and south central Canada into the Great Lakes and the eastern US (see Mid-tropospheric water vapor loop from Colorado State satellite slider). That flow will eventually tap the really cold air along the central Arctic coast of northern Canada (see 4 PM Sunday NWS WPC North America surface map). This will produce the longest stretch of colder-than-average air St. Cloud has seen since our one week of true arctic temperatures in mid-January. As has been the case so often this winter, the main lode of colder than average air will move across Hudson Bay, Ontario, and Quebec (follow the blue, colder-than-average air, by pushing the right arrow on the 850 mb temperature anomaly map from Alicia Bentley's Real-time GFS site), so we will be about 10-15 degrees colder than average, but that means highs, at worst, in the 20's, and lows in the teens. That coldest period will be from late Tuesday through Friday. It will come with a wind, similar to what we had over the weekend. The windiest period will be tomorrow and tomorrow night with gusts of 35-40 MPH, so wind chills will be in the plus single digits to below zero Tuesday night and Wednesday.
Despite near average temperatures Tuesday, the strong winds and mostly dry air will mean another day of elevated to extreme fire danger on Tuesday.
Actual Accumulating Snow? Maybe Thursday into Thursday Night?
There is the possibility of a storm moving along the southern edge of the cold air Thursday. There won't be a lot of moisture with this system, but this system may be strong enough to produce a relatively narrow band (100-150 miles) of plowable snow (4-8 inches) just to the north of its track. The presence of this system in either Minnesota or Iowa has been consistent, but the narrow band of accumulation has moved around central and southern Minnesota in the last few computer runs, so it's too early to try and pin down a potential area of snow. It's also possible that this system won't be as strong as forecast. Still, parts of Minnesota may have a snow similar to the one from Valentine's Day.
For now, I have a 50-50 shot of accumulating snow from late Wednesday night into Thursday evening, but nothing about how much.
Continued Cold Through Weekend....
This potential system will be followed by more cold air, so expect colder than average temperatures to last Friday through the weekend and into early next week.
....With Another Snow Chance Sunday?? Monday??
There is the possibility of an even stronger major Plains storm late in the weekend. The forecast models have seen this possibility as much as 10-14 days in advance, but it's still too early to say whether Minnesota will be caught up in the precipitation. If we are, much of the precipitation could fall as snow (see Days 6-7 on the NWS WPC winter weather outlook. But, at least, there are more precipitation possibilities than we've seen in a while.
Detailed St. Cloud, MN, and Vicinity Forecast
Confidence Level: "The Bugs Are Waiting for Me to Mow the Lawn"
Monday 3/18/2024: A cloudy start with a stray snow flake possible, then more sunshine through some high and middle clouds midday and afternoon, not nearly as windy, and a bit milder. High: between 35 and 40. Winds: NW 5-15 MPH in the morning, SW 10-20 MPH in the afternoon. Wind chill between 5 and 15 during the early morning, in the 20's from late morning through the afternoon. Chance of measurable snowfall: 10%.
Monday Night: Partly clear evening, some clouds late, breezy, and not quite as cool. Perhaps a late night snow flake or two. Low: between 27 and 32. Winds: SW 8-15 MPH evening, NW 10-20 MPH late at night. Wind chill in the teens. Chance of measurable snowfall: 10%.
Tuesday 3/19/2024: Cloudy with a few stray snow flakes in the morning, partly sunny in the afternoon, blustery with seasonable temperatures. High: between 37 and 42. Winds: NW 15-30 MPH with gusts over 40 MPH. Wind chill in the 20's. Chance of measurable snowfall: 10%.
Tuesday Night: Mostly clear, windy, and much cooler. Low: between 14 and 18. Winds: NW 15-30 MPH with gusts over 35 MPH evening, 10-20 MPH with gusts over 25 MPH late at night. Wind chill between -5 and +10. Chance of measurable snowfall: 10%.
Wednesday 3/20/2024: Lots of sun through some high clouds, not quite as windy, but colder. High: between 25 and 30. Winds: NW 10-20 MPH. Wind chill between 0 and 10 in the morning, between 10 and 22 in the afternoon. Chance of measurable snowfall: 10%.
Wednesday Night: Partly to mostly cloudy, lighter winds, and not quite as cold. Low: between 17 and 22. Winds: NE 5 MPH evening, SE 5 MPH late at night. Wind chill in the teens. Chance of measurable snowfall: 10%.
Confidence Level: "Extra Bugs Will Come From Every Home on the Block to Hover Around My Head"
Confidence Level: "Enough Bugs Will Fly into My Mouth to Throw Off My Diet"
Thursday 3/21/2024: Thickening clouds with a chance of steady snow or flurries developing during the midday or afternoon. Still cold. High: between 25 and 30. Winds: SE 8-15 MPH. Wind chill in the teens. Chance of measurable snowfall: 50%.
Thursday Night: Cloudy with a chance of steady snow or flurries through the evening, tapering to flurries late. Low: between 15 and 20. Winds: NE 8-15 MPH evening, shifting to NW 8-15 MPH in the early morning hours. Wind chill between 0 and 15. Chance of measurable snowfall: 50%.
Friday 3/22/2024: Cloudy, breezy, and continued cold. A chance of flurries or a few snow showers. High: between 25 and 30. Winds: NW 10-20 MPH. Wind chills: between 5 and 15 in the morning, between 10 and 22 in the afternoon. Chance of measurable snowfall: 20%.
Extended: Continued colder than average through next weekend??? A storm possible Sunday or Monday????
Forecast Confidence (10 - "The Rabbits Will Thump Even Though I Fed Them"; 0 - "The Rabbits Will Offer To Groom My Bald Spot"): 8 Monday, 7 Monday night and Tuesday, 6 Tuesday night through Wednesday night, 3 Thursday through Friday.
Yesterday's High: 31°F; Overnight Low (through 3 AM Monday): 22°F
St. Cloud Airport 24-Hour Melted Precipitation (through 3 AM Monday): Trace; SCSU 24-Hour Precipitation (through 3 AM Monday): Trace
March 18 Historical Data | High | Low |
Average Temperatures | 41°F | 23°F |
Record Temperatures | 75°F (2012) | 61°F (2012) |
4°F (1923) | -12°F (1941) |
Next Update: Tuesday, March 19, 2024 6 AM
Let me know what you think about this forecast and discussion by emailing SCSU meteorology professor Bob Weisman. Please note that I make the forecast, not the weather!
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