Thursday, April 21, 2011

4/21/11: Thursday's Weather Report

Issued at 4:37 PM CDT, Thursday, April 21st, 2011

30 day outlook for May 2011 issued by the Climate Prediction Center, Thursday April 21st, 2011.

For Duluth, MN:

33% chance for below normal temperatures with equal chances for above normal, below normal, or normal precipitation.

90 day outlook for May-July 2011 issued by the Climate Prediction Center, Thursday, April 21st, 2011.

For Duluth, MN:

40% chance for below temperatures with equal chances for above normal, below normal, or normal precipitation.

Weather History:

On this date in 1990:  A record high temperature of 76 degrees occurred at Duluth, Minnesota.
On this date in 1991:  A record low temperature of 18 degrees occurred at Duluth, Minnesota.

Weather Headlines:

*Rain or a mix of rain/snow develops Tonight
*Main brunt of this next storm arrives Friday Afternoon and continues into early Saturday
*Accumulating snow could develop for parts of our area Friday Night
*Easter weekend looks pleasant with Sunday being the warmer day of the two

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

One of the nicer days we have seen in a while as high pressure pushed off to our east causing southerly winds across our area.  High temperatures Today were in the middle 40s to lower 50s which is within a few degrees of average for late April.  Mostly sunny skies during the Morning gave way to increasing clouds during the Afternoon as low pressure heads through the Central Rockies, this low brought some rain to the Eastern Dakotas and parts of Southcentral Minnesota Today and this area of rain is northeast bound late This Afternoon.

Today's Upper Level Analysis:

Southwest flow aloft has developed in the Upper Midwest Today as another potent upper level low/upper trough progresses east through the Pacific Northwest, Northern/Central Rockies.  A lead disturbance out ahead of the main system was moving E/NE across the Northern Plains and Upper Midwest Today.  Quite a temperature contrast is in place which will help energize this storm system.  Afternoon temperatures ranged from the 80s and 90s across Texas to the 30s in portions of North Dakota.

Tonight:

Low pressure will pull out in the Western High Plains and Southcentral Plains with high pressure centered well to our east.  Southerly flow between the high and low will draw increasing amounts of moisture north into our area Tonight and this combined with a disturbance moving east out of the Northern Plains will cause some rain which will spread southwest to northeast from mid-Evening through the Overnight hours.  The majority of the precipitation that falls Tonight should be in the form of rain, but with 850mb temperatures hanging around -2 degrees C there might be some wet snow that mixes in with the rain, but little or no accumulation of snow is expected for Tonight.  Lows will mainly be in the 30s with skies turning overcast along with south or east winds under 20 mph.

Friday and Friday Night:

Low pressure heads northeast out of the Central Plains while a secondary low moves E/NE out of South Dakota.  Accompaning this low will be an upper level low/upper trough which will move into our area Friday Night.  Sufficient moisture and lift already in place will cause a more meaningful bout of precipitation in Northern-Eastern Minnesota and Northwest Wisconsin from Friday Afternoon through Friday Night.  This system will be quite dynamic and this may help in pulling down enough cold air behind the low to turn the rain over to a period of snow Friday Evening/Overnight in portions of our area.  If this change over occurs early enough, then it's possible that a 1-3" band of snow could affect parts of Northeast Minnesota and Northwest Wisconsin by early Saturday Morning.  Highs Tomorrow will be in the 30s and 40s with lows Tomorrow Night generally in the 30s.  Winds will be out of the east on Friday at 10-20 mph with north or east winds Friday Night at 10-20 mph.

Note:  Precipitation totals between Tonight and Friday Night will be in the one quarter to one half inch range for Northcentral, Eastcentral, and Northeast Minnesota with a quarter inch or less for Northern Minnesota.  Northwest Wisconsin can expect between one half to one inch of precipitation.

Extended Forecast:

Low pressure moves into Eastern Canada on Saturday with any lingering rain or snow showers in our area ending during the Morning hours.  The rest of Saturday into Sunday look dry at this time as high pressure builds into the Upper Midwest.  Highs on Saturday will mainly be in the 40s with lows Saturday Night in the 30s.  Sunday's high temperatures should reach the 50s with even an outside shot at 60 degrees in a few locales as southwest winds develop.  Lows Sunday Night will be in the 30s.  The next threat for rain moves in Monday Night or Tuesday and lingers into Wednesday, still plenty of model differences for next week, however, so things could change.

5 Day Forecast for Duluth/Superior

.Tonight...  Light rain developing between 9-11 PM with occasional light rain Overnight.  Mostly cloudy.  Low 33 to 36.  Wind east to southeast at 5 to 15 mph.

.Friday...  Mostly cloudy.  Drizzle possible at times with steadier rain developing after 3 PM.  High 36 to 40.  Wind east at 15 to 25 mph.

.Friday Night...  Rain or a mixture of rain and snow.  Low 31 to 34.  Wind east to northeast at 15 to 20 mph, becoming north Overnight.

.Saturday...  A few rain or snow showers possible during the Morning, becoming partly sunny.  High 45 to 50.

.Saturday Night...  Partly cloudy.  Low 30 to 35.

.Easter Sunday...  Partly sunny.  High 52 to 57.

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

.Monday...  Partly cloudy.  High 53 to 58.

Normal temperatures for Today

High:  52
Low:  31

Sunrise Tomorrow:  6:09 AM CDT
Sunset Tomorrow:   8:06 PM CDT

Tim