Tuesday, March 15, 2011

3/15/11: Tuesday's Weather Report

Issued at 4:31 PM CDT, Tuesday, March 15th, 2011

Weather Headlines:

*Mild temperatures to continue through the weekend
*Rain chances return for some areas Wednesday Afternoon-early Friday
*Storm threat late this weekend through the middle of next week

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

A weakening trough was moving east through Minnesota Today with low pressure of 1002mb centered in Northern Ontario Province.  A narrow band of light precipitation (about 50-75 miles wide) lasting generally around an hour affected portions of our area Today, the majority of the precipitation that fell came down as rain, but there was some wet snow and perhaps a bit of sleet mixed in from time to time in a few locales.  Sunshine increased This Afternoon west and southwest of the Iron Range and this has helped in causing temperatures to warm into the middle 40s to around 50 degrees...Mostly cloudy skies continued in Northwest Wisconsin and Eastern-Northeast Minnesota with temperatures generally in the middle 30s to around 40 degrees.  Winds Today were out of the south or southwest at 5-15 mph with a few higher gusts.

Today's Upper Level Analysis:

Water vapor satellite imagery indicates a westerly 500mb flow covering the Upper Midwest Today with an upper level low moving east into Northwestern Ontario Province.  500mb trough was in place over the Ohio Valley and Central-Eastern Great Lakes with an upper level low churning E/NE through Kentucky.  An impressive upper level jet >130 knots stretched from the Central Pacific (north of Hawaii) to the Western U.S. with an upper level low covering the Northeast Pacific.

Tonight:

Light rain along and east of a line from Ashland to Hayward to Birchwood, Wisconsin will come to an end before 8pm with dry conditions for these areas by mid-Evening.  The rest of our area will be dry through the night under partly to at times mostly cloudy skies.  There could be some fog later Tonight thanks to Today's rainfall and snowmelt, but a west to southwest wind up to 15 mph may prevent much fog from forming.  Lows Tonight will be in the 20s to around 30 degrees.

Wednesday and Wednesday Night:

A cold front will be centered to our north while another cold front moves east out of the Northern Plains.  A 35-50 knot southwesterly low level jet will develop ahead of this system and this could lead to some showers by Wednesday Afternoon or Wednesday Night, generally in Northern Minnesota.  High temperatures Tomorrow will be in the 30s and 40s with lows Tomorrow Night in the 30s.  Winds will be out of the south or southeast at 10-20 mph on Wednesday with winds out of the north, south, or west at around 20 mph or less Tomorrow Night.

Extended Forecast:

Thursday/Thursday Night (March 17th)  Cold front settles south/east through our area with a wave or two of low pressure heading E/NE out of the Western High Plains.  Eastcentral Minnesota and Northwest Wisconsin could see some rain at times Thursday-early Friday and there's even a slight chance for a thunderstorm in Northwest Wisconsin, although a better risk for a few thunderstorms will be found across the South halves of Minnesota and Wisconsin...These areas will be north-northeast of an elevated mixed layer which will support widespread 70 and 80 degree high temperatures in the Central Plains on Thursday.  High temperatures on Thursday in Northern Minnesota and Northwest Wisconsin will be in the 30s and 40s, but some 50s are possible in Northwest Wisconsin.  Lows Thursday Night will be in the 20s and 30s.

Friday and Friday Night (March 18th)  Looks fairly quiet during this period in Northern Minnesota and Northwest Wisconsin with highs in the 30s and 40s with lows in the 20s.

This weekend through the middle of next week will feature a large and deep upper level trough over the Western U.S. with an upper level ridge centered in the Southeast U.S.  Broad southwesterly flow will become established across the Plains due to the ridge to the southeast and trough out west.  It's likely that at least one low pressure system will eject out of this upper trough and affect the Upper Midwest with some rain late this weekend and early next week (March 20th-21st)  The computer models Today are trending somewhat weaker with this first low, and are trending stronger with a secondary low coming out of the Rockies Tuesday-Wednesday of next week (March 22nd-23rd)  This secondary low could become a major player in terms of giving us wind, rain, snow or ice sometime around the middle of next week.

5 Day Forecast for Duluth/Superior

.Tonight...  Partly cloudy.  Patchy fog possible late.  Low 25 to 30.  Wind southwest at 10 to 15 mph.

.Wednesday...  Partly sunny.  High 40 to 45 but turning cooler near Lake Superior.  Wind southwest, becoming east to southeast at 10 to 20 mph.

.Wednesday Night...  Mostly cloudy.  Showers possible early.  Low 30 to 35.  Wind south to southeast at 10 to 20 mph.

.Thursday...  Mostly cloudy.  Showers possible.  High 40 to 45.

.Thursday Night...  Mostly cloudy.  Low 27 to 32.

.Friday...  Mostly cloudy.  High 38 to 43.

.Friday Night...  Partly cloudy.  Low 22 to 27.

.Saturday...  Partly cloudy.  High 40 to 45.

Normal temperatures for Tomorrow

High:  34
Low:  16

Sunrise Tomorrow:  7:20 AM CDT
Sunset Tomorrow:   7:15 PM CDT

Tim