Tuesday, September 30, 2014 6:00 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
Welcome Back to October
We had October-like weather earlier in September but yesterday marked an abrupt return to the chilly conditions. The cold front went through on Sunday evening (see 24-hour loop of WPC North Central surface maps), so temperatures were falling into the morning hours (see NWS: Last 72 hours of St. Cloud Observations). Our high temperature for yesterday was a near-average 63 degrees, but that was reached at 1 AM. The highest temperature during the day was a chilly 58 degrees. Throw in the clouds and the wind and it felt a lot cooler. After skies cleared out overnight, temperatures were headed for the middle to upper 30's in much of central Minnesota (see UCAR
Minnesota surface chart loop). In St. Cloud and some areas, there were leftover low clouds and some spotty drizzle, keeping temperatures in the 40's. Still, this morning will likely be the coolest morning St. Cloud has seen since September 16's low of 38 degrees.
We have one last weather system approaching us from the southwest. That is the well-developed "comma cloud" coming out of Colorado early this morning (see infrared loop from College
of DuPage Satellite and Radar Menu). The high clouds from this system are already moving into Minnesota. However, a relative lack of moisture is confining most of the rain showers to the northern portion of the low from Colorado into Canada (see radar loop from College
of DuPage Satellite and Radar Menu). This system will have trouble getting its rain through the cooler air over us, so we will get through the bulk of the day with that spotty drizzle this morning and just a lot of clouds through the afternoon. Temperatures will only be able to recover to the upper 50's to near 60.
Our best chance of showers and thunderstorms will come this evening as the storm pushes northeastward through the Dakotas and into southern Canada (see NWS HPC Short-Range forecast map). The worst thunderstorms with some risk of severe weather will stay in central and eastern South Dakota.
Tomorrow, the cold front from this system will come through. We'll start off the day cloudy, but could see some afternoon sunshine. There will also be a slight chance of a late day shower. Tomorrow will be our warmest day of the next several with a high around 70 degrees.
By Thursday, the switch in the upper-air steering winds to a more northwest-to-southeast direction (see water vapor loop from College
of DuPage Satellite and Radar Menu) will be complete. Much cooler air will be moving in. We'll have a lot of instability clouds in the afternoon with perhaps a few scattered showers. Temperatures will stay in the lower 60's with a strong northwest wind.
Much cooler air will push in on Thursday night. We may see a few light rain showers overnight into Friday morning. But, the big change will be the chilly air with highs staying in the lower half of the 50's Friday and Saturday. A clear night looks to be on tap for Friday night, so that will be our next threat of frost. Some of the colder spots around the area could see their first hard freeze (lows of 28 or lower) of the season.
Slightly warmer air will build in on Sunday, pushing highs back into the 60's, but another cool surge could knock highs back into the 50's for early next week.
Despite the coolness of today and yesterday, September will finish with well-above average temperatures. Through yesterday, the average temperature was 61.5°F, 2.8°F above average. Despite the huge early month rain, September has produced a total of 4.05 inches, 0.68 inch above average.
See Forecast Below
Ground and Air Travel
Tuesday 9/30: Cloudy with some spotty morning drizzle, then mostly cloudy the rest of the day, breezy, and cool. High: between 55 and 60. Winds: SE 10-20 MPH. Chance of measurable rainfall: 10%.
Tuesday Night: Breezy and mild with showers or thunderstorms likely, especially during the evening. Low: between 52 and 56. Winds: SE 10-15 MPH with higher gusts in storms. Chance of measurable rainfall: 70%.
Wednesday 10/1: Some morning sunshine, then some afternoon clouds with a slight chance of a shower or thunderstorm. Noticeable humidity. High: between 67 and 72. Winds: SW 10-20 MPH. Chance of measurable rainfall: 20%.
End of "Reasonable" Forecast Certainty
Wednesday Night: Partial clearing, breezy, and turning cooler and drier again. Low: between 45 and 50. Winds: NW 5-15 MPH. Chance of measurable rainfall: 10%.
Thursday 10/2: A sunny start, then rapidly clouding up by early afternoon. Occasional afternoon showers, breezy, and cooler. High: between 62 and 66. Winds: NW 10-20 MPH. Chance of measurable rainfall: 40%.
Thursday Night: Partly to mostly cloudy, breezy, and cooler. A chance of a rain showers towards morning. Low: between 40 and 45. Winds: W 5-10 MPH. Chance of measurable rainfall: 30%.
Friday 10/3: Fast forward to Halloween. Cloudy with perhaps an early rain shower, then partly sunny, windy, and much cooler. High: between 50 and 55. Winds: NW 15-25 MPH with higher gusts. Chance of measurable rainfall: 30%.
For Entertainment Purposes Only.
Friday Night: Partly clear and cooler. A good chance of frost. Low: between 28 and 34. Winds: NW 5-10 MPH. Chance of measurable rainfall: 10%.
Saturday 10/4: Sunny, not quite as windy, but continued cool. High: between 52 and 56. Winds: WNW 10-20 MPH. Chance of measurable rainfall: 10%.
Saturday Night: Partly to mostly cloudy. A shade warmer. Low: between 35 and 40. Winds: NW 5-10 MPH. Chance of measurable rainfall: 10%.
Sunday 10/5: Sunny and a little more seasonable. High: between 60 and 65. Winds: NW 5-10 MPH. Chance of measurable rainfall: 10%.
Extended: Cooler than average weather pattern continues into next week.
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, 7 Tuesday, 6 Tuesday night and Wednesday, 5 Wednesday night through Friday, 3 Friday night and Saturday, 2 Sunday.
Yesterday's High: 63°F (set at 1 AM); Yesterday's Daytime High: 58°F; Overnight Low (through 6 AM): 43°F
St. Cloud Airport Rainfall (Since 3 AM Monday): 0.11 inch; SCSU Rainfall (Since 3 AM Monday): 0.13 inch
Normal Temperatures for September 30 - High: 65°F;
Next Update: Wednesday, October 1, 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!
Are you interested in studying meteorology? If so,
go to the Earth and Atmospheric Sciences Department home page.