Tuesday, September 2, 2014 3:30 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
Quieter, September-Like Temperatures For Most of the Next 7 Days
Drying Out After Weekend Deluge
The Labor Day Weekend ended up producing most of an average August dose of rain. The St. Cloud Airport had 3.14 inches of rain since late Thursday night with a widespread 2-5 inches in much of central Minnesota. As noted in my my St. Cloud August and meteorological summer weather summary, both the growing season (since April 1) and the calendar year rainfall rank as the third heaviest on record through the end of August.
Drier air did work its way into Minnesota after the morning thunderstorms finished yesterday. Dew points finally dropped back into the more comfortable 50's during the day (NWS: Last 72 hours of St. Cloud Observations), a big contrast to those oppressive 70-degree dew points on Sunday. There were a few isolated showers that did pop up in the afternoon. A storm in west central Minnesota produced penny-sized hail with a few hail stones of quarter-size in Alexandria and Gull Lake.
The drier weather will continue today with those morning clouds clearing out and highs again in the 70's to perhaps near 80.
More Storms Late Tomorrow Through Early Thursday
Showers and thunderstorms are back in the forecast from tomorrow afternoon into Thursday. By tomorrow morning, the pump of more humid air over the top of the cooler air near the ground will likely produce showers and thunderstorms across Iowa and Missouri in the early morning. We will likely see the high clouds from that system early in the day. However, as the front to our south (see NWS
HPC Latest North American zoom-in surface map) returns northward as a warm front, there will be a better chance of showers and thunderstorms developing in the middle to late afternoon. There is a threat of severe weather in central and southern Minnesota late tomorrow afternoon into tomorrow evening. Large hail and damaging winds are the primary threats, but there could even be a tornado or two right along the afternoon position of the warm front. Those storms will be possible tomorrow night as the sticky air really shoves into Minnesota and again as the cold front from this system pushes through during the daylight hours of Thursday morning. That means there is more potential for some heavy rainfall.
Canadian Air Means Drying Out and Cooling a Bit Through the Weekend
However, the weather pattern is changing to a drier one, so the quieter weather will resume the second half of Thursday and continue through the weekend and into next week. The steering winds (seen on the water vapor loop from College
of DuPage Satellite and Radar Menu) have shifted to a more west-northwest to east-southeast pattern, instead of coming from the west or southwest. That means it will be much harder for the really sticky air that we saw on Saturday and Sunday to move into Minnesota. Instead, we will see a series of air masses from the Canadian Prairie Provinces. Our current air mass is warm enough to produce highs from the upper 70's to perhaps lower 80's today through Thursday. However, the next Canadian air mass to push in for Friday will likely drop highs to around 70 degrees on Friday and in the low to middle 70's for the weekend. Clear nights will produce low temperatures in the 40's, levels we've only seen once (July 17) since mid-June.
See Forecast Below
Ground and Air Travel
Tuesday 9/2: Sunny in the morning, some high clouds in the afternoon, continued seasonably warm and dry. High: between 75 and 80. Winds: SW 8-15 MPH. Chance of measurable rainfall: 10%
Tuesday Night: Partly clear, breezy, and not quite as cool. Low: between 55 and 60. Winds: SW 5-12 MPH. Chance of measurable rainfall: 10%.
Wednesday 9/3: Increasing clouds with a good chance of showers and thunderstorms in the middle and late afternoon. High: between 74 and 78. Winds: SE 10-15 MPH. Chance of measurable rainfall: 20% in the morning, 50% in the afternoon.
Wednesday Night: A good chance of showers and thunderstorms, much warmer and uncomfortably humid. Low: between 65 and 70. Winds: SW 5-12 MPH. Chance of measurable rainfall: 50%.
Thursday 9/4: A good chance of early showers and thunderstorms, then clearing by midday, breezy, and becoming less humid. High: between 77 and 82. Winds: becoming WNW 10-20 MPH. Chance of measurable rainfall: 50% in the morning, 20% in the afternoon.
Thursday Night: Mostly clear, breezy, cooler and drier. Low: between 48 and 54. Winds: NW 8-15 MPH. Chance of measurable rainfall: 0%.
Friday 9/5: Sunny, breezy, and cooler. High: between 68 and 72. Winds: WNW 8-15 MPH. Chance of measurable rainfall: 0%.
End of "Reasonable" Forecast Certainty
Friday Night: Partly clear and continued cool. Low: between 46 and 52. Winds: W 5 MPH. Chance of measurable rainfall: 0%.
Saturday 9/6: Morning sun, some afternoon clouds, breezy, and a bit more seasonable. High: between 72 and 76. Winds: WNW 8-15 MPH. Chance of measurable rainfall: 0%.
Saturday Night: Clear and cool. Low: between 45 and 50. Winds: W 5 MPH. Chance of measurable rainfall: 0%.
Sunday 9/7: Continued sunny and dry. High: between 72 and 76. Winds: SW 5-15 MPH. Chance of measurable rainfall: 0%.
For Entertainment Purposes Only.
Extended: Dry weather continues early next week with slow warming. Next chance of storms not until Tuesday????
Forecast Confidence (10 - "Know what gas will
cost next week, Bob?"; 0 - "Been a victim of road rage lately, Bob?"): 8 Tuesday and Tuesday night, 7 Wednesday through Friday, 5 Friday night through Sunday, 3 early next week.
Yesterday's High: 78°F; Overnight Low (through 4 AM): 60°F
St. Cloud Airport Rainfall (Since 7 AM Monday): None (3.14 inches since Friday); SCSU Rainfall (Since 7 AM Monday): None (2.84 inches since Friday)
Normal Temperatures for September 2 - High: 76°F;
Next Update: Wednesday, September 3, 2014 8:00 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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go to the Earth and Atmospheric Sciences Department home page.