Monday, September 27, 2010

9/27/10: Monday's Weather Report

Issued at 4:14 PM CDT, Monday, September 27th, 2010

Weather tidbits:

*Low temperature of 31 degrees at the Duluth Airport on Sunday, September 26th, 2010 was the first time since May 10th, 2010 with a minimum temperature of 32 degrees or lower.

*Last year's first freezing (32 degrees) low temperature occurred on October 8th at Duluth, Minnesota compared to September 26th this year.

Low temperature report for Monday, September 27th, 2010.  Source:  NWS Duluth, Minnesota.

Hayward WI:  33 degrees
Sky Harbor MN:  32 degrees
Two Harbors MN:  34 degrees
Silver Bay MN:  28 degrees
Superior WI:  34 degrees
Embarrass MN:  22 degrees
Floodwood MN:  28 degrees
Butternut WI:  30 degrees
Upson WI:  30 degrees
Gordon WI:  30 degrees
Spooner WI:  31 degrees
Solon Springs WI:  33 degrees

Low temperature report for Sunday, September 26th, 2010.  Source:  NWS Duluth, Minnesota.

Duluth MN:  31 degrees
International Falls MN:  34 degrees
Hibbing MN:  27 degrees
Ashland WI:  28 degrees
Hayward WI:  27 degrees
Two Harbors MN:  28 degrees
Silver Bay MN:  25 degrees
Grand Marais MN:  25 degrees
Ely MN:  25 degrees
Crane Lake MN:  28 degrees
Eveleth MN:  28 degrees
Aitkin MN:  32 degrees
Cloquet MN:  30 degrees
Superior WI:  28 degrees
Siren WI:  29 degrees
Bruno MN:  29 degrees
Embarrass MN:  22 degrees
Floodwood MN:  28 degrees
2 miles south of Tower MN:  28 degrees
7 miles northwest of Two Harbors MN:  26 degrees
Butternut WI:  31 degrees
Danbury WI:  32 degrees
Solon Springs WI:  29 degrees

Weather History:

*On this date in 1987...  A record high temperature of 83 degrees occurred at Duluth, Minnesota.
*On this date in 1991 and previous years...  A record low temperature of 27 degrees occurred at Duluth, Minnesota.

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

A not so dry front after all.  A cold front has moved into Eastern Minnesota late This Afternoon.  Enough moisture with dewpoints in the 40s to around 50 degrees combined with PWS around 0.80" in combination with some lift provided by a 110 knot jet streak over the Red River Valley of Minnesota caused some showers and thunderstorms over the North half of Minnesota This Morning which moved into Northeast-Eastern Minnesota and Northwest Wisconsin This Afternoon.  Dangerous lightning strikes and brief heavy downpours have been the main risks from these storms Today.  Favorable LAPSE RATES >6.5 c/km and cold temperatures aloft -14 degrees C also contributed to these surprise storms Today.  High temperatures Today ranged from the lower to middle 50s in far Northeast Minnesota with 60s to lower 70s for the rest of our area.  Winds Today were out of the south, west or north under 20 mph.

Today's Upper Level Analysis:

Northwest flow aloft covered the Upper Midwest Today per water vapor satellite imagery and RUC model analysis.  A large upper level low was in place from the Ohio Valley through the Southeast U.S. while a massive upper level ridge of high pressure prevailed over the Western U.S.


A fairly strong disturbance and cold front will exit Northeast Minnesota and Northwest Wisconsin This Evening.  A few showers in eastern parts of Northwest Wisconsin and also in the Arrowhead of Minnesota will come to an end This Evening, otherwise for Tonight expect partly to mostly cloudy skies with the potential for a few lake effect rain showers Overnight, generally from Bayfield through Ashland and Iron counties in Northwest Wisconsin.  Lows Tonight will be in the 40s with some 30s in northern areas.  Winds will shift to the north in all locations at 10-20 mph.

Tuesday and Tuesday Night:

High pressure will stretch from Central Ontario Province south to the Upper Midwest on Tuesday before it shifts off to our south/east by Tuesday Night.  Partly-mostly cloudy skies are expected on Tuesday with the possibility for a few lake effect rain showers during the Morning along the South Shore of Lake Superior, possibly also affecting areas west toward the Twin Ports.  Highs Tomorrow will be in the 50s with 60s from the Brainerd Lakes and areas west-northwest.  Winds Tomorrow will be out of the north/east under 20 mph.  Partly cloudy skies are forecast Tuesday Night with lows in the 30s and 40s with variable winds turning to the south.

Extended Forecast:

Low pressure averaging 991 mb will move across Central Canada on Wednesday with a cold front and a potent upper level disturbance/upper trough pushing south/east through the Upper Midwest.  This appears to be a similar setup to what happened Today, so a few showers and perhaps even a late season thunderstorm cannot be ruled out across Northern Minnesota and Northwest Wisconsin on Wednesday.  Highs will be in the 50s and 60s, but a few southern areas could approach 70.  Lows Wednesday Night will be in the 30s and 40s with any showers ending early in the Evening.  Dry weather is on tap for Thursday and Thursday Night with highs in the 50s to lower 60s with lows in the 30s to lower 40s.  Looks like the pattern will amplify late this week or this weekend with a northerly flow aloft developing across the Great Lakes/Upper Midwest.  A couple of chilly Autumn days are possible if this pattern develops, and there might even be a few lake effect rain showers from Friday Night into Saturday Night along the South Shore of Lake Superior, some of these rain showers could mix with ice pellets or snow flakes at night or during the early Morning hours especially if the long range models are correct by showing 850 mb temperatures lowering to -4/-7 degrees C by Saturday.

5 Day Forecast for Duluth/Superior

.Tonight...  Partly to mostly cloudy.  Low 40 to 45.  Wind west at 5 to 15 mph, becoming north at 10 to 20 mph.

.Tuesday...  Partly sunny.  Showers possible early.  High 53 to 58.  Wind northeast at 10 to 20 mph.

.Tuesday Night...  Partly cloudy.  Low 37 to 42.  Wind variable at 5 to 12 mph.

.Wednesday...  Variable cloudiness.  Afternoon showers or thunderstorms possible.  High 60 to 65.  Chance of rain 20%.

.Wednesday Night...  Partly to mostly cloudy.  Low 40 to 45.

.Thursday...  Partly sunny.  High 55 to 60.

.Thursday Night...  Mostly clear.  Low 40 to 45.

.Friday...  Mostly cloudy.  High 50 to 55.

Normal High Temperature Today 61 degrees
Normal Low Temperature Today 41 degrees