Saturday, May 21, 2011

5/21/11: Saturday's Weather Report

Issued at 4:56 PM CDT, Saturday, May 21st, 2011

Rainfall totals from Friday Night and Saturday Morning...Ending around 6 AM CDT Today.  Source:  NWS Duluth, MN.

Brainerd, MN:  0.55"
4 miles south of Bruno, MN:  0.30"
12 miles north of Isle, MN:  0.87"
3 miles northeast of Nisswa, MN:  0.67"
Dixon Lake, MN:  0.20"

WEATHER HEADLINES:

-Periods of rain continuing into Monday
-Scattered thunderstorms Tonight and Sunday
-A couple strong storms possible Sunday Afternoon for parts of the area
-Cool/drier weather takes over after Monday and persists into the middle of the week

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

Low pressure of 996mb was centered in extreme Northwest South Dakota as of 4 PM CDT Today.  A rather large area of rain has been lifting north across our area Today, as of late Afternoon the majority of the steadier rainfall has pushed into far Northern Minnesota through the Arrowhead and down through portions of Northwest Wisconsin.  Clearing has worked it's way into Southern areas This Afternoon and the atmosphere was becoming moderately unstable late Today across Central and Southern Minnesota where scattered severe thunderstorms have been developing west of the Twin Cities.  Highs Today were in the 50s and 60s with 40s near Lake Superior.  Winds Today were out of the southeast or east at 5-15 mph with some higher gusts.

Today's Upper Level Analysis:

500mb low and trough covered the Northern/Central Plains and Upper Midwest per RUC model analysis and water vapor satellite imagery.  Several impulses are rotating around the 500mb low and are helping to generate waves of showers and thunderstorms in parts of South Dakota, Nebraska, Iowa, and Minnesota This Afternoon.

Tonight:

Low pressure will drift into South Dakota with an occluded front pushing north through our area.  An area of rain will end by mid-Evening in far Northern-Northeast Minnesota with a few late night showers possible for these same areas.  Elsewhere, expect scattered showers and thunderstorms with the greater risk for a few storms around the Brainerd Lakes area, east to Pine county Minnesota, and in Northwest Wisconsin.  The best instability will remain south of our area Tonight, but CAPES are forecast to climb to 500-1000 j/kg in Southern areas Tonight with Lifted Indices of zero to -2 degrees C.  Lows Tonight will be in the 50s to around 60 degrees with 40s near Lake Superior.  Winds Tonight will be out of the south or east under 20 mph.

Sunday and Sunday Night:

Low pressure of 994-996mb in Eastern South Dakota Tomorrow Morning will move E-NE into Central Minnesota Sunday Afternoon, then into Northcentral Wisconsin by late Tomorrow Night.  A strong upper level low will also lift E-NE out of the Northern Plains and into the Upper Midwest during this period.  Good lift will be found out ahead of this storm, and this should lead to periods of showers in our area for Sunday and Sunday Night. 

Thunderstorms are also expected Sunday and Sunday Evening for Northwest Wisconsin and Eastcentral Minnesota with a spotty thunderstorm risk for Northern Minnesota Sunday Afternoon.  CAPES of 500-1000 j/kg will be in place Sunday Afternoon in Northwest Wisconsin into portions of Northern-Eastern Minnesota with Lifted Indices of -1 to -3 degrees C.  A 60-80 knot SW mid level jet will be found on the southeast side of the surface and upper level low while a 25 to 35 knot southerly low level jet will develop ahead of the low in Northwest Wisconsin and Eastern Minnesota. 

The greatest risk for possible severe weather for Sunday Afternoon and Evening will be south of our local area.  But Northwestern Wisconsin...Especially along and south of a line from Grantsburg to Spooner to Park Falls have an isolated severe thunderstorm risk with large hail and damaging winds being the main threats.  Storms that form in Northcentral and Eastern Minnesota should stay below severe limits Tomorrow, but a few strong storms may develop with a risk for some quarter to half inch size hail.

Partly sunny to mostly cloudy skies are expected on Sunday with highs in the 60s and 70s but it will be cooler near Lake Superior.  Lows Tomorrow Night will be in the 40s and 50s.  Winds will be out of the south, east, or north under 20 mph.

Note:  Areas of fog will be found through Sunday Night especially near Lake Superior.  Some of the fog could be dense at times.

Note:  Rainfall totals by Monday should be in the 0.50-1.50" range in Northern Minnesota and Northwest Wisconsin with localized higher amounts possible.

Extended Forecast:

Low pressure will exit to our east-northeast on Monday with a cold front dropping south across our area.  A lingering risk for rain will continue on Monday with dry weather returning from Monday Night into Wednesday.  High temperatures for Monday and Tuesday will be in the 50s and 60s with lows Monday Night and Tuesday Night in the 30s and 40s.  Note:  There could be some patchy frost Tuesday Night and Wednesday Night in some parts of our area.

5 DAY FORECAST FOR DULUTH/SUPERIOR

.Tonight...  Areas of fog and drizzle.  Overcast with scattered showers.  Low 45 to 50.  Wind east to southeast at 5 to 15 mph.

.Sunday...  Areas of fog and drizzle.  Mostly cloudy with occasional showers.  Isolated thunderstorms also possible.  High 60 to 65 but cooler near Lake Superior.  Wind east to southeast at 10 to 15 mph.

.Sunday Night...  Areas of fog and drizzle during the Evening.  Mostly cloudy with occasional showers.  Isolated thunderstorms possible early.  Low 45 to 50.  Wind east at 10 to 15 mph, becoming north to northwest Overnight.

.Monday...  Mostly cloudy.  Occasional showers.  High 57 to 62.

.Monday Night...  Decreasing cloudiness.  Low 35 to 40.

.Tuesday...  Partly cloudy.  High 55 to 60 but cooler near Lake Superior.

.Tuesday Night...  Partly cloudy.  Low 35 to 40.

.Wednesday...  Partly cloudy.  High 60 to 65 but cooler near Lake Superior.

Normal temperatures for Tomorrow

High:  66
Low:  42

Sunday's Pollen Forecast:

Tree:    Moderate
Grass:  None
Weed:  None

Sunrise Tomorrow:  5:26 AM CDT
Sunset Tomorrow:   8:45 PM CDT

Tim