Wednesday, March 9, 2011

3/9/11: Wednesday's Weather Report

Issued at 3:33 PM CST, Wednesday, March 9th, 2011

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

Low pressure of 1008mb was centered over Southern Lake Michigan (just east of Chicago, Illinois) as of 3 PM.  This storm was just too far southeast of our area to give us any snow Today, the exception to this was in portions of Northwest Wisconsin where some snow did fall Today with a couple inches of accumulation, especially in parts of Sawyer and Price counties.  There's been a few flurries and pockets of light snow at times in parts of Northcentral Minnesota due to a weakening disturbance, but little accumulation has occurred.  Otherwise the big story Today was the overcast skies with north or east winds under 15 mph, although winds were stronger near Lake Superior with gusts up to 25 mph.  High temperatures Today were mainly in the 30s.

Today's Upper Level Analysis:

500mb trough dominated the Northern-Central Plains and Upper Midwest per water vapor satellite imagery with a vigorous area of low pressure pushing northeast across the Great Lakes.  The southern portion of this storm led to a severe weather outbreak yesterday and Today with a preliminary severe weather count at 128 including 22 tornadoes from the Arklatex through the deep South.

Tonight:

Low pressure heads into Eastern Michigan with high pressure moving east from the Northern Plains.  Partly to mostly cloudy skies will be found in our area Tonight with areas of light snow and flurries ending This Evening.  Up to another inch of snow could accumulate in parts of Northwest Wisconsin, but most areas will have little if any accumulation.  Lows Tonight will be in the teens and 20s with north or east winds becoming north-northwest under 20 mph.

Thursday and Thursday Night:

Upper level trough scoots off to the east with an upper level ridge building in from the Northern Rockies and Northern Plains.  High pressure passing through the Upper Midwest will result in dry weather across our area with high temperatures on Thursday in the 30s to around 40 degrees with lows Thursday Night in the teens and 20s.  North or west winds will become south or southwest Tomorrow Night, wind speeds will be under 20 mph.

Extended Forecast:

A vigorous upper level low/trough will dig S-SE across the Northern Plains and Upper Midwest from Friday Afternoon through Saturday with a surface low tracking E-SE through the Red River Valley and Northern Minnesota Friday Night before exiting to our east on Saturday.  Southwesterly low level jet will increase to 30-45 knots out ahead of this system on Friday with strong warm air advection occurring in the Upper Midwest with 850mb temperatures of +2 to +8 degrees C.  High temperatures on Friday will be in the 30s and 40s in Northern Minnesota and Northwest Wisconsin with some 50s possible farther west and south.  Lows Friday Night will be in the 20s and 30s.

The risk for snow or rain will increase a bit Friday Night and Saturday with any rain switching over to snow late Friday Night or Saturday Morning.  The forecast models continue to struggle with this system, but the trend Today has been to lower the expected precipitation/snowfall totals which makes sense since it is a clipper type low.  The potential still exists for a 1-3" snowfall Friday Night and or Saturday for Northern Minnesota with an inch or less expected for Northwest Wisconsin and Eastcentral Minnesota.  Saturday will feature some gusty winds as cold air advection flows in on northwesterly breezes which could reach 25 mph.  Highs on Saturday will occur early in the day when 20s and 30s will be common, thereafter expect falling temperatures to the teens and 20s.  Lows Saturday Night will be in the single digits and teens.

For the most part the Upper Midwest will be influenced by a zonal 500mb flow next week with a couple low pressure systems and cold fronts pushing through the Upper Midwest.  There could be some showers of snow or rain at times next week as those systems move through, but nothing too significant is expected at this time.

5 Day Forecast for Duluth/Superior

.Tonight...  Considerable cloudiness.  Low 18 to 23.  Wind northeast at 10 to 20 mph, becoming north to northwest.

.Thursday...  Partly cloudy.  High 35 to 40.  Wind northwest at 10 to 15 mph.

.Thursday Night...  Partly cloudy.  Low 18 to 23.  Wind becoming south around 12 mph.

.Friday...  Partly cloudy.  High 38 to 43.

.Friday Night...  Mostly cloudy.  Snow or rain possible late.  Low 25 to 30.

.Saturday...  Snow showers or flurries possible.  Up to 1" accumulation possible.  Mostly cloudy.  High 30 to 35 with falling temperatures.

.Saturday Night...  Partly to mostly cloudy.  Low 8 to 13.

.Sunday...  Partly cloudy.  High 25 to 30.

Normal temperatures for Today

High:  31
Low:  14

Sunrise Tomorrow:  6:32 AM CST
Sunset Tomorrow:   6:07 PM CST

Tim