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Monday, March 2, 2015 2:35 PM
Prepared by Bob Weisman
Professor of Earth and Atmospheric Sciences
Saint Cloud State University
Earth and Atmospheric Sciences Department
Saint Cloud and Vicinity Forecast
Synopsis: Snowstorm of the Year Tuesday...Maybe (but 2 Inches Would Qualify)
Faster Storm Means Less Snow Potential Tomorrow Morning
The main change in this morning's forecast computers is to move the forecast storm faster. However, the big change is that they don't appear to be working together very well. The northern storm is taking shape over northern Saskatchewan and the southern one has now moved into southern California (see water vapor from College
of DuPage Satellite and Radar Menu), but the northern storm is forecast to basically fly through late tonight into the morning commute. That means a shorter period of accumulating snow here. The snow should start around 1 or 2 AM, continue through the rush hour, but taper off by 9-10 AM. Because of the shorter period of accumulating snow, I'm rolling back my snow accumulations slightly to the 2-4 inch range and applying it from Alexandria through St. Cloud and eastward to Hinckley, then also southward, including Redwood Falls, Willmar, Hutchinson, and the Twin Cities. It looks like the best chance of more snow would be from Fergus Falls to Brainerd to Hinckley, which could see 3-6 inches from this system. There will be even lighter snowfall in Mankato, Marshall, Owatonna and Rochester, with perhaps only an inch or two.
So, expect snow-covered roads with icy spots. Sometimes, 1-2 inches on the ground can cause a lot of accidents if people don't slow down accordingly.
Winds Produce Some Blowing Snow, Icy Spots Tomorrow Midday and Afternoon
That still leaves the problem of blowing snow causing low visibility and icy spots in open areas tomorrow midday and afternoon. The winds will begin to pick up shortly after the snow ends tomorrow morning, with northwest winds of 20-30 MPH plus gusts to 40-45 MPH throughout the Upper Minnesota River Valley, the Buffalo Ridge, and south central Minnesota. That will still cause some areas of low visibility at times, although I expect it to be scattered due to the lower snowfall totals. In the St. Cloud to Twin Cities corridor, we will see winds of 20-30 MPH with gusts at times to 35-40 MPH.
The winds will pick up as the temperatures drop back from the 20's during the morning to the teens in the afternoon, so I would expect to see some icy spots where snow blows across roadways. The winds will also be strong enough to shove a vehicle sideways where there are cross winds (on north-south roads, and of course, Hwy. 23). You can follow the road conditions on the MnDOT road conditions site.
The area of north central Minnesota expecting the most snow won't have winds quite as strong as in Morris or Albert Lea, so the winter weather advisory will cover those 3-6 inch amounts with some blowing snow in the afternoon in Brainerd, Lake Mille Lacs, and Duluth. I also expect the winter weather advisory to stay up for that light snowfall in Alexandria, St. Cloud and the Twin Cities. Parts of the blizzard warning may be replaced by the winter weather advisory as the new computer information is updated by the National Weather Service later today.
In this scenario, the southern system will have a fairly good moisture supply, and the stronger lift, but the northern system will allow enough cold air into the storm to turn the precipitation to frozen form at the northern fringe of it. So, this time, Kentucky and Tennessee will get a good amount of rain, at least tomorrow. (There is a chance that the precipitation ends as snow, or even ice in Arkansas, on Wednesday).
Perhaps the most serious travel problem tomorrow is that the northern fringe of the southern storm will produce significant ice accumulation in the Chicago area tomorrow morning. If that happens over O'Hare, it could mess up travel nationwide. There will be 3-6 inches in interior Wisconsin, most likely affecting Eau Claire, and Green Bay with lower snow or wet snow totals over Madison and Milwaukee.
Colder Outbreak the Rest of the Work Week
As has been the case so often this winter, the air flow behind the northern storm system will be out of north central Canada, so the arctic high pressure area in the northern Yukon Territories (see NWS
HPC Latest North American zoom-in surface map) will come barreling southward into the eastern two-thirds of North America. This air will be as cold as the coldest of our outbreaks so far this winter. Given that kind of cold air this late in the season, we actually could see some record cold temperatures, which have been few and far between so far this winter.
Blizzard Warning Just to the West of St. Cloud Tomorrow Afternoon
On the way down, the departing low and the new high will combine to produce very strong northwest winds. Winds will be blowing at 20-30 MPH tomorrow afternoon with gusts to 40 MPH into the evening and remain at 10-20 MPH late Tuesday night. Those winds will begin to blow by midday. Even after the storm, there won't be that much snow on the ground, but the blowing snow could produce icy spots and areas of low visibility tomorrow afternoon and night.
There is a blizzard warning out from central South Dakota all the way to Glenwood, Willmar, Litchfield, Hutchinson and points west for all of tomorrow into tomorrow evening. That's for the potential of the significant snow in the morning, followed by the strong northwest winds in the afternoon. Alexandria, St. Cloud, and the Twin Cities are in a winter weather advisory for the snow early tomorrow, followed by blowing snow problems afterward. The blizzard warning is in effect where the highest wind gusts (35-45 MPH) and the significant snow (3-5 inches) are expected.
Temperatures will be in the lower 20's at the end of tomorrow's snow and could climb briefly towards 30 as we spend a short time in the warm sector of the storm early tomorrow afternoon. However, temperatures will be knocked back into the teens by sunset and drop to the minus single digits by Wednesday morning. That means wind chills in the minus 20s to near -30 on the NWS
wind chill chart. Highs will only recover to the lower plus single digits. So, we have a shot at the March 4 record cold high of 8 degrees, set in 1917 and 2003. The winds will ease up on Wednesday night, but that would allow low temperatures to plunge well into the minus teens and perhaps approach -20. It would take at least a low of -17 to get into record cold territory Thursday morning, but we could be close. Thursday will feel better after the cold start, since winds will remain light and the sun will be out. So, a high of 10 degrees will be more comfortable, even though it will be close to the March 5 record cold high of 7 degrees, set in 1943.
Temperatures will moderate beginning Thursday night with those less cold conditions continuing into next weekend. Temperatures will stay between 5 and 10 Thursday night with a few flurries. Highs will return to the 20's on Friday. On Saturday and Sunday, there could be a weak storm going by which might spread some flurries. However, temperatures will continue to be less ridiculously cold with highs in the 20's. Still, I don't see any day, except for a brief time after the snow ends and before the cold comes in tomorrow midday, with a shot at an average early March high in the low to middle 30's.
I'll be working on the February and Winter 2014-2015 St. Cloud weather summary today.
See Forecast Below
Forecast: Rest of Monday 3/2: Plenty of sunshine and a bit breezy. High: between 27 and 30. Winds: S-SE 10-20 MPH. Chance of measurable snowfall: 10%.
Winter Weather Advisory 11 PM Monday Night Through 9 AM Tuesday
Monday Night: Thickening clouds with snow developing in the early morning hours. A coating of 1-2 inches could be on the ground by morning. .Low: between 14 and 18. Winds: SE-S 10-25 MPH. Chance of measurable snowfall: 20% evening, 80% after midnight.
Tuesday 3/3: Snow falling at a moderate rate through mid-morning, then tapering to flurries by late morning. Another one to 2 inches could accumulate between 7 and 10 AM, producing a total of between 2 and 3 inches between midnight and 9 AM tomorrow. Clearing, turning windy, and colder during the afternoon. Low visibility and icy roads due to blowing snow. High: between 24 and 28. Winds: S 10-20 MPH in the morning, becoming NW 20-30 MPH with higher gusts in the afternoon. Chance of measurable snowfall: 80% through noon, 20% afternoon.
Tuesday Night: Clear, windy, and much colder with bitter wind chills. Low: between -8 and -3. Winds: WNW 15-30 MPH evening, 10-20 MPH late. Wind chills: in the minus 20s to near -30. Chance of measurable snowfall: 10%.
Wednesday 3/4: Sunny and breezy with the return of ridiculous cold. High: between 3 and 8. (record cold high: 8 in 1917 and 2003) Winds: NW 10-20 MPH. Wind chills: in the minus 20s to near -30 in the morning, between -25 and -10 in the afternoon. Chance of measurable snowfall: 10%.
End of "Reasonable" Forecast Certainty
Wednesday Night: Clear with diminishing wind and much colder. Low: between -18 and -13. (record cold low: -17 in 2003) Winds: W 5 MPH. Spotty wind chills between -35 and -20. Chance of measurable snowfall: 10%.
Thursday 3/5: Sunny and not quite as ridiculously cold. High: between 12 and 16. (record cold high: 7 in 1943) Winds: SW 8-15 MPH in the afternoon. Afternoon wind chill between -15 and -5. Chance of measurable snowfall: 10%.
Thursday Night: Clouding up and not as cold. A chance of some flurries or fog late at night. Low: between 5 and 10. Winds: SW 5-15 MPH, becoming NW 5 MPH late. Chance of measurable snowfall: 10%.
Friday 3/6: Partly sunny, breezy, and actually seasonable. High: between 32 and 37. Winds: WNW 8-15 MPH. Chance of measurable snowfall: 10%.
For Entertainment Purposes Only.
Friday Night: Cloudy with a chance of light snow or flurries late at night. Low: between 20 and 25. Winds: SW 5-15 MPH, becoming NW 8-15 MPH late. Chance of measurable snowfall: 20%.
Saturday 3/7: Partly sunny, breezy, and still seasonable. High: between 30 and 35. Winds: WNW 8-15 MPH. Chance of measurable snowfall: 10%.
Extended: Another seasonably mild day on Sunday.
Forecast Confidence (10 - "Know what gas will
cost next week, Bob?"; 0 - "Been a victim of road rage lately, Bob?"): 7 Thursday through Sunday, 6 Sunday night and Monday, 5 Monday night and Tuesday, 4 Wednesday, 3 Thursday and Friday.
Today's High: 26°F (through 2 PM); Overnight Low (through 8 AM): 0°F
St. Cloud Airport Precipitation: None; SCSU Precipitation (Through 3 AM Monday): None
Normal Temperatures for March 2 - High: 31°F;
Low: 12°F
Next Update: Tuesday, March 3, 2015 8:00 AM (or as needed)
Links:
Surface
Satellite
Radar
Current Watches/Warnings
Ground and Air Travel
Climate
Drought
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!
Are you interested in studying meteorology? If so,
go to the Earth and Atmospheric Sciences Department home page.
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