Friday, January 7, 2011

1/7/11: Friday's Weather Report

Issued at 4:11 PM CST, Friday, January 7th, 2011

January climate stats for Duluth, Minnesota (Airport location)

Average monthly temperature:  8.4 degrees
Normal precipitation:  1.12"
Normal snowfall:  19.6"

Lake effect snow storm to continue through Saturday Night along the South Shore of Lake Superior.

*LAKE EFFECT SNOW WARNING*

Lake effect snow warning is now in effect until 12 AM CST Saturday Night.  This includes the Northwest Wisconsin counties of Bayfield...Ashland...and Iron.  Lake effect snow showers, heavy at times will persist in the warning area through Saturday Night.  Some cities that will be affected include:  Port Wing WI...Bayfield WI...Washburn WI...Grand View WI...Drummond WI...Ashland WI...High Bridge WI...Upson WI...Gile WI...Hurley WI...and Montreal WI.

Main impacts:  Visibilities as low as one quarter mile at times in heavy snow.  Hourly snowfall rates of 1-2" in some areas.  Total snowfall accumulations of 6-12" are expected by Saturday Night in the warning area with localized amounts approaching 20" possible, especially in Ashland and Iron counties.  Snow accumulations thus far have ranged from 6.5" at Montreal, WI (Iron county) to 2.0" at Gile, WI (Iron county)

A lake effect snow warning means significant amounts of lake effect snow accumulations are expected that will make travel very hazardous or impossible.  It is common for lake effect snow accumulations and snowfall rates to vary greatly over very short distances.  Some locations may receive one to several inches of snow per hour for a period of several hours.  Strong winds are likely to cause blowing and drifting snow.  Near zero visibility may occur in the heaviest snow showers.  If you must travel be aware that you may become stranded and that it may take many hours for help to arrive.  Keep a winter survival kit in your vehicle, including a flashlight, food, and water.  Let someone know your travel route and expected time of arrival and have a working cell phone in case you become stranded.

Weather history:

On this date in 2003:  A record high temperature of 46 degrees occurred at Duluth, Minnesota.

Weather headlines:

*Cold weather through next week
*Two snow systems worth monitoring, one early next week, the second late next week
*Siberian outbreak possible late next week or next weekend

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

Strong low pressure of 991 mb was centered in Eastern Upper Michigan late This Afternoon with high pressure of 1020 mb in Eastern Saskatchewan Province.  Cold northerly winds with plenty of clouds and scattered light snow showers and flurries with accumulations under 1" were found in our area Today on the backside of this system with heavier lake effect snow affecting the South Shore of Lake Superior from Douglas county, east through Iron county.  High temperatures Today were in the single digits to around 10 above zero which is about 5-10 degrees below average for early January.  Winds Today were out of the north or west at 10-20 mph.

Today's Upper Level Analysis:

500mb troughs covered the Northeast Pacific/Northwest Canada.  Another upper level trough was moving into the Southwest U.S.  A large 500mb trough was in place from Eastern-Central Canada, south through the Plains, through the Eastern U.S. with an upper level low covering the Eastern Great Lakes.  A corridor of strong upper level winds (110-140 knots) was in place from the Northern Plains to Southern Missouri, east through the Carolinas per RUC model analysis.

Tonight through Saturday Night:

Surface and upper level low will continue to churn to our east while high pressure remains to our west.  Scattered flurries will come to an end This Evening, otherwise partly to mostly cloudy skies will be found in our area Tonight and Tomorrow with clear to partly cloudy skies Tomorrow Night.  Lake effect snow will continue along the South Shore of Lake Superior, although the threat should end by late Tonight or Saturday Morning for Douglas county (south-east of the city of Superior)  Total snowfall accumulations for Douglas county will range from 1-3", again this would be south-east of the city of Superior.  Low temperatures Tonight and Saturday Night will be in the single digits, teens, and 20s below zero with highs Tomorrow in the single digits to lower teens.  North or west winds under 20 mph will persist during this period with lowest wind chills of 15 below to around 30 below zero Tonight and Tomorrow Morning, and perhaps again Tomorrow Night.

Extended Forecast:

Sunday and Sunday Night look dry with highs in the single digits and teens with lows in the single digits, teens, and 20s below zero.  The period from Monday through Tuesday of next week will feature a slow moving upper level low pressure system which is expected to drop south/east out of the Western High Plains, an inverted trough will extend north of that 500mb low and will be the focus for a persistent area of snow from the Dakotas through parts of Minnesota with several inches of accumulation expected.  At this time it looks like the bulk of the heavier snow (4+" totals) will setup west-south of our local area, however, the potential does exist for a couple inches of snow early next week, especially from the Brainerd Lakes toward Pine City, and possibly into portions of Northwest Wisconsin.  Surface winds could also veer toward the east early next week, depending on how this system evolves, if that happens and with cold air in place, then some lake effect snow showers could develop along the North Shore of Lake Superior...including the Twin Ports.  High temperatures on Monday will be mainly in the teens with lows Monday Night in the single digits below to around 10 above zero.

Latest long range model runs suggest some sort of a low/s to develop over the Rockies or Plains out ahead of a massive dome of arctic air which will develop in Western-Central Canada late next week.  There could be some snow for the Upper Midwest late next week, followed by a bitter blast for next weekend that could be accompanied by life threatning wind chills.  Certainly a period to keep an eye on during the next several days.

5 Day Forecast for Duluth/Superior

.Tonight...  Light snow showers or flurries early, otherwise partly to mostly cloudy.  Low 5 below to 10 below.  Wind north to northwest at 10 to 20 mph.  Lowest wind chills of 15 below to 25 below zero.

.Saturday...  Partly cloudy.  High 7 to 12.  Wind northwest at 10 to 15 mph.

.Saturday Night...  Partly cloudy.  Low 10 below to 15 below.  Wind west to northwest at 5 to 15 mph.

.Sunday...  Partly cloudy.  High 8 to 13.

.Sunday Night...  Partly cloudy.  Low 3 below to 8 below.

.Monday...  Partly sunny.  Flurries possible.  High 13 to 18.

.Monday Night...  Mostly cloudy.  Flurries possible.  Low 5 to 10.

.Tuesday...  Mostly cloudy.  Flurries possible.  High 15 to 20.

Normal temperatures for Today:

High:  17
Low:  -1

Tim