Saturday, September 5, 2015 8:12 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
I Always Wanted A Steam Bath for Labor Day
Last Batch of Storms This Morning, Much More to Come
Another Round of Storms Overnight With Flooding Possible
Yet another batch of storms were triggered over Minnesota overnight (see infrared loop from College
of DuPage Satellite and Radar Menu) by a storm that was in northwestern Mexico two days ago (see water vapor loop from College
of DuPage Satellite and Radar Menu). Even though the storms kept moving, there was nearly half an inch of rain in the St. Cloud area (0.46 inch Airport, 0.42 inch SCSU). Those storms have pushed off into Wisconsin (see
Upper Mississippi Valley radar loop), but there continues to be a good flow of moisture all the way from the leftovers of Tropical Storm Kevin moving into west Mexico through New Mexico and Colorado. That next system will push through the Dakotas and Minnesota tonight, so we will have another shot at showers and thunderstorms developing late this afternoon and continuing most of the night. Given the tropical moisture over us with dew points hovering around 70 or even higher (see NWS
Aviation Center Minnesota map), there is the possibility of some heavy rainfall. The best chance of some localized flooding (since the ground is wetter) is across eastern North Dakota and northwestern and north central Minnesota, but we could end up with some locally heavy downpours as well. There may be a chance of some straight line damaging winds as well.
More Risk of Flooding in Tomorrow's Storms...Maybe Some Wind Damage?
The cold front from the Washington State storm will finally drag through Minnesota tomorrow evening. We will have a lot of lingering clouds and a few showers and thunderstorms tomorrow morning from the late night activity. But, as the cold front moves through, there will be an afternoon wave of showers and thunderstorms. The upper-level winds will be a bit stronger than today, but I don't anticipate getting as much sunshine as we've seen the past couple of days.The NWS Storm Prediction Center has most of Minnesota in a slight risk of severe thunderstorms, but the lesser amount of sun should keep the threat to the possibility of straight line damaging winds and heavy downpours. It is also possible that the bulk of the storms redevelop whereever the Saturday night storms end up, robbing some momentum from the afternoon storms. So, there isn't a great chance of severe weather.
Once again, the main threat will be the possibility of some heavy downpours producing localized flooding.
Steam Heat Through Sunday Evening
The high humidity of the past three days will continue through tomorrow. Today, I do expect a fair amount of clouds to develop this afternoon, so I expect high temperatures to be a shade cooler than yesterday (note that temperatures were considerably cooler in North Dakota yesterday than on Thursday when Bismarck and Pierre broke 100 degree), but temperatures in the middle 80's with stifling 70's dew points will feel quite oppressive. Tomorrow, I expect even less sunshine, so highs will likely stay around 80 degrees or a little above. Lows overnight will be no cooler than the upper 60's and perhaps stay in the 70's.
Actual September Weather by Monday
When do we get relief from the heat and, especially, the humidity? When the main storm in Washington moves through the Canadian Prairie Provinces, some of the much cooler air seen in Alberta and Saskatchewan (60's, 50's and even some 40's for highs yesterday) will start drive into the Northern Plains. That kind of cold will stay out of the US, but we will be much more comfortable Monday into the early part of next week. Highs will stay in the 70's with dew points much more comfortable. Th
The storm track won't be far away, so we could see a chance of showers Monday night and possibly Wednesday, but it will no longer be July into October.
Confidence Level: "I Will Still Have Dandruff Tomorrow"
Saturday 9/5: Mixed clouds and sun, breezier, very warm and still steamy. A chance of scattered late day showers and thunderstorms. High: between 84 and 88. Winds: S 10-20 MPH. Chance of measurable rainfall: 20% rest of the morning, 40% in the afternoon.
Saturday Night: Sticky with showers and thunderstorms likely. Heavy downpours and straight line damaging winds are possible. Low: between 67 and 72. Winds: S 10-20 MPH. Chance of measurable rainfall: 70%.
Sunday 9/6: Lingering morning showers and thunderstorms, then mostly cloudy, breezy, and continued oppressively humid. A chance of late day showers and thunderstorms. High: between 80 and 85. Winds: S 10-25 MPH. Chance of measurable rainfall: 50%.
Confidence Level: "The Twins Will Finish Above .500"
Sunday Night: Showers and thunderstorms ending evening, then clearing, cooler and less humid late at night. Low: between 55 and 60. Winds: becoming NW 10-20 MPH late. Chance of measurable rainfall: 30%.
Monday 9/7: Sunny to partly cloudy, breezy, drier, and more seasonable. High: between 74 and 78. Winds: N 8-15 MPH. Chance of measurable rainfall: 10%.
Confidence Level: "The Cat Will Not Sit on My Grading"
Monday Night: Partly clear with a chance of showers and thunderstorms. Low: between 55 and 60. Winds: SE 5-10 MPH. Chance of measurable rainfall: 30%.
Tuesday 9/8: Partly sunny, warm, and dry. High: between 74 and 78. Winds: NW 8-15 MPH. Chance of measurable rainfall: 10%.
Extended: Chance of storms again Wednesday????
Forecast Confidence (10 - "Know what gas will
cost next week, Bob?"; 0 - "Been a victim of road rage lately, Bob?"): 7 Thursday, 6 Thursday night and Friday, 5 Friday night and Saturday, 4 Saturday night and Sunday, 3 Sunday night and Monday.
Yesterday's High: 89°F; Overnight Low (through 7 AM): 72°F
St. Cloud Airport 24-Hour Precipitation (through 7 AM Saturday): 0.46 inch; SCSU Precipitation (Through 7 AM Saturday): 0.42 inch
Normal Temperatures for September 5 - High: 75°F;
Next Update: Sunday, September 6, 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.