Issued at 3:24 PM CST, Saturday, February 7th, 2009
Surface Analysis at 21z:
High pressure averaging 1024 mb was centered over Southeast Montana with low pressure averaging 996 mb centered over Western Quebec. Cold front attached to the Quebec low extended from Central Michigan to Central Illinois to Northcentral Missouri. Temperatures along and ahead of this boundary warmed into the 50s, 60s, and 70s Today from Illinois back through Southern Iowa and Missouri. A secondary cold front was analyzed from Central Lake Superior back toward Eastcentral Minnesota. The storm set to hit Minnesota early next week had moved into Northwest Arizona with a 1008 mb surface low centered in that area This Afternoon.
Upper Air Analysis at 21z:
H5 flow was out of the west across the Upper Midwest, but a shortwave heading east-southeast out of North Dakota attm will turn the flow to the northwest for about 12-18 hours. A nice looking storm per water vapor satellite imagery that tracked through Minnesota last night was now over Eastern Canada late Today with 12 hour 500 mb height falls of 120 meters centered over Eastern Ontario and Western Quebec This Afternoon… A big storm was turning southeast through the Southwest U.S. and Southern Rockies This Afternoon with the 500 mb low centered over Central-Southern California. Copious amounts of mid and high level moisture was evident per water vapor satellite imagery over the Southwest U.S. toward the Central and Southern Plains out ahead of this strong storm Today. H85 temperatures around Minnesota at 3 PM Today ranged from +2 to +6 degrees C in Southern Minnesota to -8 degrees C across the North.
Last night’s low pressure system that tracked through Minnesota was a potent one, but it lacked moisture, and as a result it came through mostly on the dry side. Areas of haze and fog did occur though last night into early Today, but as this low pulled east and cold advection developed…The fog and haze burned off leaving behind partly sunny to mostly cloudy skies. A new disturbance heading into the state from North Dakota has been generating some flurries and areas of light snow Today across parts of Northern, Central, and Western Minnesota…But hardly any accumulation has been reported. High temperatures were mostly in the 20s and 30s Today with winds turning into the west or north at 10 to 20 mph along with some higher gusts.
Temperatures around Minnesota at 3 PM ranged from 35 degrees at St Paul to 19 degrees at Hallock to 27 degrees at International Falls to 28 degrees at Two Harbors to 25 degrees at Fergus Falls to 30 degrees at Aitkin to 27 degrees at Cloquet to 30 degrees at Jackson to 34 degrees at Faribault to 37 degrees at Austin.
Upper level disturbance will continue to track east-southeast across the state This Evening and will exit to our east by later in the night. High pressure building in behind this feature will cause skies to clear out at least somewhat across Minnesota Tonight with any flurries or light snow showers in Northern and Central Minnesota ending This Evening. Lows Tonight will be in the single digits and teens with some spots in the North possibly falling a couple degrees below zero. Winds will be out of the west or north around 20 mph or less.
Sunday and Sunday Night:
*Winter Storm Watch* goes into effect late Sunday Night for parts of far Northwest Minnesota and far Western Minnesota. Some cities included in the watch are… Crookston… Moorhead… Hallock… Warren… And Breckenridge.
High pressure will slide to the east of Minnesota during this period while the flow aloft transitions from the northwest back to the southwest. Low pressure will be heading northeast out of the Southwest U.S. during this period with the low by 6 AM Monday forecast to be over Eastern Colorado-Western Kansas. Increasing 850 mb jet of 30 to 45 knots will begin to draw warm and moist air north and northwest into Minnesota by Sunday Night and this will cause precipitation to break out over the Western half of the state at that time. Freezing rain looks to be the main precipitation type Sunday Night over Western Minnesota with the precipitation turning over to rain over Southwest areas of the state. Central and Southern Minnesota could also see some freezing rain develop Overnight Sunday. Look for partly cloudy to sunny skies across the state on Sunday with highs in the 20s and 30s. By Sunday Night, look for increasing cloudiness throughout the state with lows in the single digits, teens, and 20s with rising temperatures into the 30s down South. Winds on Sunday will be out of the south, east, or west at 5 to around 20 mph. Winds Sunday Night will be out of the south or east at 10 to 20 mph.
*Winter Storm Watch* is in effect Monday through Tuesday Afternoon over Northwest and Westcentral Minnesota. Some cities included in the watch are… Roseau… Baudette… Thief River Falls… Fosston… Bagley… Bemidji… Mahnomen… Park Rapids… Detroit Lakes… Fergus Falls… Elbow Lake… And Wadena…
*Winter Storm Watch* is in effect Monday Morning through Tuesday Morning for much of Northern and Northeast Minnesota…
Low pressure will be deepening and turning negatively tilted on Monday as it lifts north-northeast from Eastern Colorado-Western Kansas toward Eastcentral South Dakota Monday Evening…The low is then forecast to reach Eastern North Dakota or Northwest Minnesota by Tuesday Morning. The majority of the forecast models Today are in pretty good agreement on the storm track, with the EURO and more so the NAM forecasting a further south and east storm track…Right now those two models seem to be the outliars. Pressures near the center of the low could drop below 990 mb, possibly as low as 985 mb or so as it heads toward Western Minnesota or the Eastern Dakotas Monday Night-Tuesday Morning.
There’s going to be a tremendous amount of warm air and moisture surging north into Minnesota out ahead of this storm system on Monday with 850 mb temperatures expected to get into the +2 to +6 degree C range over most areas of the state through late Monday Night. PWATS are expected to climb into the .50″-.75″ range as well which is very high for this time of year around Minnesota. This moisture surge will he propelled by a potent low level jet out of the south at 35-55 knots.
For Monday…Look for freezing rain possibly mixed with some sleet or rain across Western Minnesota while any freezing rain down South turns over to rain during the Morning. Freezing rain and possibly some sleet should spread into Central, Eastern, and Northern Minnesota during the day with the precipitation possibly becoming all rain over Central and Eastern Minnesota.
For Monday Night…Look for freezing rain, sleet, or rain across Western and Northern Minnesota while mainly rain falls from Central to Eastern to Southern Minnesota. The bulk of the precipitation after Monday Evening should shift out of Southern Minnesota as the mid level dry slot helps to shut off the precipitation down in that area. There still is a potential for a few thunderstorms Monday Afternoon or Evening over the Southern half of Minnesota thanks to some weak instability that will rotate north-northeast around the deep low off to the west. Any severe weather should remain south of Minnesota though the way it looks now.
For Tuesday…Look for a mix bag of precipitation in the form of wet snow, sleet, freezing rain, and possibly some rain over Western, Central, and Northern areas of the state with precipitation likely turning over to some wet snow and snow flurries as heights fall and colder air works in aloft as the upper level low tracks into Minnesota and the Dakotas. Any precipitation that lingers into Tuesday shouldn’t be as heavy though the way it looks now.
The potential exists for one quarter inch or more of ice accumulations from early Monday through Tuesday Morning from Western through Northeast Minnesota… Total snowfall amounts by late Tuesday could reach 1 to perhaps 2 inches in Northern and Western Minnesota.
Ice could accumulate enough to cause some power outages and possibly down some trees around the areas of the state I mentioned above.
In addition to the ice potential, there remains the possibility for some flooding in areas that see rain early next week. Snow depths per Air Force observations indicate that Southwest Minnesota has no snow left on the ground as of Friday Evening, but snow depths range from 2″ to 5″ across the South half of the state with up to 10″ of snow still left on the ground in Southeast Minnesota…Rain falling on top of this will run-off since the ground is still frozen…This could lead to some flooding, especially near rivers and streams as well as in low lying areas and poor drainage areas. Snow depths are greater the farther north you go in Minnesota, so if temps warm enough to melt any ice that was to accumulate, and rain falls on top of this…Then, flooding could creep north and west into other parts of the state early next week.
High temperatures around Minnesota will be in the 30s and 40s on Monday with some 20s lingering near Lake Superior. Lows Monday Night will hold steady from the day’s high temperatures. Then on Tuesday look for highs to be in the 30s and 40s with some 20s possible Northwest. Lows Tuesday Night will be in the teens, 20s, and 30s.
Forecast for Duluth/Superior:
*Winter Storm Watch* now in effect from Monday Morning through Tuesday Morning.
.Tonight… Mostly cloudy This Evening with skies becoming mostly clear late. Low 10 to 15. Wind northwest to west at 10 to 20 mph.
.Sunday… Mostly sunny. High 25 to 30. Wind west to southwest at 10 to 20 mph.
.Sunday Night… Increasing cloudiness. Low 10 to 15. Wind southwest at 10 to 15 mph, becoming east.
.Monday… Freezing rain or sleet developing… High 27 to 32. Chance of precipitation 40%.
.Monday Night… Freezing rain, sleet, or rain along with areas of fog. Low 27 to 32 with slowly rising temperatures. Chance of precipitation 100%.
.Tuesday… Light freezing rain or rain possible in the Morning with a few rain or snow showers in the Afternoon. High 32 to 38. Chance of precipitation 50%.
.Tuesday Night… A few flurries possible. Mostly cloudy. Low 15 to 20.
4 PM Thompson Hill Observation:
Current Temperature: 29.7 degrees
Dewpoint: 19 degrees
Wind: NW at 6 mph G 14 mph
Max Temperature Today: 34.5 degrees
Max Humidity Today: 94%
Min Temperature Today: 27 degrees
Min Humidity Today: 66%
Normal High Temperature Tomorrow 22 degrees
Normal Low Temperature Tomorrow 3 degrees