Monday, April 20, 2015 3:47 AM
Prepared by Bob Weisman
Professor of Earth and Atmospheric Sciences
Saint Cloud State University
Earth and Atmospheric Sciences Department
Saint Cloud and Vicinity Forecast
Major Storm, But Major Rainfall Just Misses St. Cloud
The strong low pressure system did cloud us up Saturday afternoon with persistent clouds from Saturday night through this morning. However, the bulk of the rainfall stayed just to the east of St. Cloud. Southern, east central and northeastern Minnesota have picked up a widespread half-inch plus of rain and even Little Falls had nearly half an inch with the Brainerd area getting three-quarters to an inch. St. Cloud only saw .18 inch Saturday night and Sunday morning with generally 0.10 to 0.25 inch in a swath of central Minnesota. The 2.12 inches in St. Cloud since the start of the year is now only about half of the 4.28 inch average.
Overnight, another wave of major rainfall parked across eastern Minnesota (see radar loop from College
of DuPage Satellite and Radar Menu) It was in the Twin Cities around midnight, but is now only affecting the Arrowhead and southeastern Minnesota (see (see NWS
Upper Mississippi Valley radar loop). This wave of rain is still being produced by leftover thunderstorms on the northwestern flank of low pressure system number 1, now pushing through Missouri (see water vapor loop from College
of DuPage Satellite and Radar Menu). The moisture has been pulled north and west of the main low pressure system (see infrared loop from College
of DuPage Satellite and Radar Menu), but then has been stopped by the second low pressure system, which has spent the past day pushing from Manitoba into the eastern Dakotas and western Minnesota. That trailing system will dominate our weather for the next couple of days.
Cold Low to Produce Cold, Windy, Showery Weather Through Tomorrow
As the new low pushes into Minnesota this morning, it will tend to sweep the southern low's rain off to the east. However, that trailing low is associated with a pocket of really cold air aloft. Note from yesterday's visible satellite loop (see College
of DuPage Satellite and Radar Menu and wait through the "dark" hours), how many clouds popped up in Manitoba and the Dakotas, all of which began Sunday with clear skies. That's because the huge difference between ground temperatures and temperatures at 18,000 feet above the ground allowed a bunch of cumulus clouds and some instability rain showers. That will be our weather trend today.
We will have those mostly cloudy skies today. However, by the middle of the afternoon, some of those clouds will be able to build up enough to produce some occasional rain showers. The temperatures aloft will be cold enough to even produce snow showers. Look for a mixture of rain and snow showers this afternoon. These showers will continue through the evening hours with the colder temperatures giving us a better chance of seeing snow make it to the ground. These showers will be on and off and only briefly heavy in spots, but a coating of snow from one of them might be possible. There could end up being an inch or two in the Arrowhead with more significant snow possible in northern Wisconsin and the Michigan Upper Peninsula.
If you were counting on the late week weather to resume with highs in the 70's, you're going to have to go somewhere else this week. The cold air associated with the back low will dominate Minnesota and much of the Great Lakes into the Northeast this week. High temperatures will remain stuck in the 40's, typical of about a month ago. Also, the northwest winds have really cranked up overnight with gusts as high as 32 MPH (see NWS: Last 72 hours of St. Cloud Observations). These winds will increase today to speeds of 20-35 MPH with gusts over 40 MPH. The National Weather Service has issued a wind advisory for most of central, west central, and south central Minnesota between 11 AM and 7 PM. Vehicles traveling on north-south roads could easily be shoved, and it will worse, of course, along Hwy. 23.
Tomorrow will be a near repeat of today, except that the chance of afternoon rain and snow showers will be a little. Highs will continue to be stuck in the middle 40's.
Cool Week On Tap With the Return of Sunshine
The old low will slowly push into eastern Canada by the middle of the week, which will finally allow the development of clouds to ease off. The return of sunshine for the second half of the work week will allow highs to moderate enough to brush 50 degrees on Wednesday and Friday and climb into the 50's on Thursday. The strong northwest winds will continue at 10-20 MPH each day, but ease off a bit each night. Those lighter winds, however, will allow low temperatures to drop into the 20's.
The stalled pocket of cold air near the US-Canadian border will keep the main west-to-east storm track to our south. So, while areas of even California to Texas to the Carolinas pick up some rain, we will be high and dry once we get rid of the upper level low by mid-week.
See Forecast Below
Wind Advisory 11 AM-7 PM Monday
Monday 4/20: Cloudy, blustery, and much cooler. Occasional afternoon rain or snow showers. High: between 42 and 46. Winds: NW 20-30 MPH with gusts of 40-50 MPH. Chance of measurable precipitation: 50%.
Monday Night: Cloudy, breezy, and colder. A chance of an occasional snow shower. A coating of snow on grass is possible by morning. Low: between 32 and 36. Winds: NW 10-25 MPH. Chance of measurable snowfall: 40%.
Tuesday 4/21: Cloudy, not quite as windy, and continued cold. A chance of a rain or snow shower. High: between 42 and 46. Winds: NW 10-25 MPH. Chance of measurable precipitation: 40%.
Tuesday Night: Cloudy evening, partial clearing possible late. Still breezy, and colder. Low: between 24 and 28. Winds: NW 8-15 MPH. Chance of measurable precipitation: 10%.
Wednesday 4/22: Sunny, breezy, and not quite as cold. High: between 45 and 50. Winds: NW 10-25 MPH. Chance of measurable precipitation: 10%.
Wednesday Night: Clear, light winds, and colder. Low: between 20 and 25. Winds: NW 5 MPH. Chance of measurable precipitation: 10%.
Thursday 4/23: Sunny, breezy, and not quite as cold. High: between 50 and 55. Winds: NW 10-20 MPH. Chance of measurable precipitation: 10%.
End of "Reasonable" Forecast Certainty
Thursday Night: Partly clear and continued cool. Low: between 24 and 28. Winds: NE 5-10 MPH. Chance of measurable precipitation: 10%.
Friday 4/24: Sunny, and a shade cooler. High: between 45 and 50. Winds: NE 5-15 MPH. Chance of measurable precipitation: 10%.
For Entertainment Purposes Only.
Friday Night: Clearing, less windy, and continued cool. Low: between 24 and 28. Winds: NW 5-15 MPH. Chance of measurable snowfall: 10%.
Saturday 4/25: Partly clear and not quite as cold. High: between 52 and 56. Winds: NW 5-15 MPH. Chance of measurable snowfall: 10%.
Extended: Transition back to warmer than average the following week.
Forecast Confidence (10 - "Know what gas will
cost next week, Bob?"; 0 - "Been a victim of road rage lately, Bob?"): 8 Monday through Tuesday, 7 Tuesday night, 6 Wednesday through Thursday, 5 Thursday night and Friday, 3 Friday night and Saturday.
Yesterday's High: 54°F; Overnight Low (through 3 AM): 39°F
St. Cloud Airport 24-Hour Precipitation: 0.18 inch; SCSU Precipitation (Through 3 AM Monday): TBA
Normal Temperatures for April 20 - High: 59°F;
Next Update: Tuesday, April 21, 2015 8:00 AM (or as needed)
Ground and Air Travel
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.