Monday, May 4, 2015 3:06 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
May Some Rain Cross Your Path
Narrow Miss for Both 80 and Rain
It was a very warm and increasingly humid weekend, but in St. Cloud, the weather fell short in two key ways. The high each day this weekend made it only to 79 degrees (see 3-day loop of US high temperatures from SUNY-Albany), so we are still lacking our first 80 degree high. Also, there was enough humidity (dew points in the noticeable middle 50's on the NWS: Last 72 hours of St. Cloud Observations) and a front sufficient to trigger a lot of afternoon showers and thunderstorms, but the front came through St. Cloud too early, so we got a great view of the showers to our south and east yesterday afternoon (see infrared loop from College
of DuPage Satellite and Radar Menu). Those storms produced large hail and wind damage from the Twin Cities into southeastern Minnesota, northwestern Iowa and Nebraska. So, we had to settle for some early morning light showers that only produced 0.04 inch in St. Cloud.
The cold front that triggered the storms has now pushed through Minnesota (see NWS
HPC Latest North American zoom-in surface map). Dew points have fallen back into the dry 30's (see NWS
Aviation Center Minnesota map) and temperatures have fallen back into the 40's. We may see a few 30's before the morning rush hour.
Significant Rain Potential from Tuesday Night On
However, this week promises a better chance for significant rainfall across much of Minnesota. The storm in eastern Pacific approaching California (see infrared loop from College
of DuPage Satellite and Radar Menu) will tour the Rockies and the High Plains, moving through the Dakotas and into Manitoba and Ontario by Friday. Ahead of this system, the warmth and moisture that is being pushed southward by yesterday's cold front will have a relatively short trip to get back into Minnesota. That means a chance for showers and thunderstorms beginning mainly tomorrow night and continuing into at least Friday. The first wave happens as the warm and sticky air pushes over the slightly cooler air near the ground tomorrow night into Wednesday. We may see a few scattered showers and thunderstorms as early as tomorrow afternoon, but the best chance will be tomorrow night into Wednesday morning. The warm front from this system may get stuck in central Minnesota, so it will cause showers and thunderstorms to develop near the warm front Wednesday afternoon into Wednesday evening. Then, whatever showers and thunderstorms develop along the cold front in the Plains should move into Minnesota late Wednesday night into Thursday.
On Thursday night and Friday morning, the cold front from this system comes through, bringing another chance of showers and thunderstorms.
Of course, thunderstorm forecasting, even 2-3 days down the road can be iffy. These days will not likely be a complete washout with significant breaks in the storms on Wednesday and possibly Thursday. If we get a good supply of sunshine, temperatures will climb well into the 70's with significant humidity. Thursday is the most likely day to stay cloudy with highs in the lower 70's.
At this point, it looks like cooler weather for the weekend but how cool is uncertain.
Before we get to the rain, we should have a dry 30-36 hours. Look for sunny skies today with highs near 70 and a strong northeast wind. There may still be an elevated fire danger this afternoon. Under partly clear skies, temperatures will again drop into the 40's overnight.
See Forecast Below
Monday 5/4: Mostly sunny, breezy, drier, and not quite as warm. Very high fire danger. High: between 68 and 72. Winds: NE 8-15 MPH. Chance of measurable rainfall: 10%.
Monday Night: Partly clear, breezy, and cool. Low: between 42 and 46. Winds: E 8-15 MPH. Chance of measurable rainfall: 10%.
Tuesday 5/5: Thickening clouds, windy, and not as warm with a chance of a late day afternoon shower or thunderstorm. Not as warm. High: between 62 and 66. Winds: SE 15-25 MPH. Chance of measurable rainfall: 30%.
Tuesday Night: Good chance of showers and thunderstorms. Mild. Low: between 50 and 55. Winds: SE 8-15 MPH. Chance of measurable rainfall: 60%.
Wednesday 5/6: Maybe a lingering morning storm, then mixed sun and clouds, warm, and more humid with scattered afternoon showers and thunderstorms. High: between 75 and 80. Winds: S 10-25 MPH. Chance of measurable rainfall: 50%.
End of "Reasonable" Forecast Certainty
Wednesday Night: Warm and increasingly humid. A chance of a late night thunderstorm. Low: between 58 and 63. Winds: SE 10-20 MPH. Chance of measurable rainfall: 40%.
Thursday 5/7: Showers and thunderstorms possible both in the morning and late in the afternoon. Still breezy and humid. High: between 72 and 77. Winds: S 10-20 MPH, becoming SW 15-30 MPH late. Chance of measurable rainfall: 60%.
Thursday Night: Maybe an evening thunderstorm, then slowly turning less humid and not quite as warm. Low: between 50 and 55. Winds:SW 10-25 MPH evening, W 8-15 MPH late. Chance of measurable rainfall: 30%.
For Entertainment Purposes Only.
Friday 5/8: Partly sunny, breezy, and not quite as humid. A chance of an afternoon brief shower? High: between 65 and 70. Winds: NW 10-20 MPH. Chance of measurable rainfall: 20%.
Extended: Cooler with less chances for showers???
Forecast Confidence (10 - "Know what gas will
cost next week, Bob?"; 0 - "Been a victim of road rage lately, Bob?"): 8 Monday and Monday night, 6 Tuesday through Wednesday, 5 Wednesday night through Thursday night, 4 Friday.
Yesterday's High: 79°F; Overnight Low (through 3 AM): 44°F
St. Cloud Airport 24-Hour Precipitation: 0.04 inch; SCSU Precipitation (Through 3 AM Monday): TBA
Normal Temperatures for May 4 - High: 64°F;
Next Update: Tuesday, May 5, 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.