Tuesday, September 28, 2010

9/28/10: Tuesday's Weather Report

Issued at 3:04 PM CDT, Tuesday, September 28th, 2010

Weather tidbits:

*65 degree high temperature on Monday, September 27th, 2010 at Duluth, Minnesota was the warmest high temperature since September 12th when the high temperature was 68 degrees.

*9/27/10 marked only the 6th time this month with an above normal high temperature at Duluth, Minnesota.

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

Plenty of clouds persisted throughout the day in Northwest Wisconsin back through Eastern and Northeastern Minnesota while skies started to clear out This Afternoon over Northern Minnesota.  High temperatures Today ranged from the upper 40s to middle 50s near Lake Superior with mid 50s to lower 60s for the rest of our area.  Winds Today were out of the east, south or north under 20 mph.  Surface map as of 2 PM featured high pressure of 1014 mb centered over Central Ontario Province with low pressure of 998 mb centered in Southeast Ontario Province with low pressure of 1000 mb centered along the Saskatchewan-Manitoba Province line.

Today's Upper Level Analysis:

Water vapor satellite imagery reveals a rather amplified weather pattern in place across the U.S.  A strong jet stream >110 knots was in place from the Central Pacific through Central Canada with a N/NW 500 mb flow covering the Upper Midwest while a large upper level ridge of high pressure covered the Western U.S. while an upper level low was in place over the Eastern Great Lakes/Ohio Valley region.

Tonight:

High pressure will be centered to our north/east while low pressure stays off to our northwest.  A cold front attached to this low should be entering western parts of our area toward dawn.  Warm advection will be in full swing Overnight with 850 mb temperatures of around +6 degrees C This Afternoon increasing to +8/+14 degrees C later Tonight as southerly winds develop out ahead of this low pressure system.  Partly-mostly cloudy skies will be found in our area Tonight with lows generally in the 40s, but a few locales could slip into the 30s depending on sky conditions.  Winds Tonight will be out of the east or south under 20 mph.

Wednesday and Wednesday Night:

Low pressure will move into Central Ontario Province during this period with a cold front attached to this low pushing southeast through our area on Wednesday which will also be accompanied by a rather potent disturbance and cold temperatures aloft (500 mb temps around -15 degrees C) Partly sunny-mostly cloudy skies are forecast for Tomorrow with scattered showers or isolated thunderstorms with dry conditions returning Wednesday Night under partly-mostly cloudy skies.  No severe weather is expected on Wednesday due to a limited amount of moisture and instability, but some brief heavy downpours, occasional lightning strikes and wind gusts up to 30-35 mph are possible in the strongest activity.  Highs Tomorrow will be in the 50s and 60s, but a few southern locales could reach 70 degrees.  Lows Tomorrow Night will be in the 40s.  Westerly winds from 10-25 mph are expected during this period.

Extended Forecast:

Dry weather is forecast in Northern Minnesota and Northwest Wisconsin Thursday and Thursday Night
with highs in the 50s to lower 60s with lows in the 30s and 40s.  The 500 mb flow will amplify beginning on Friday and continuing through the weekend with a sharp northerly flow developing over the Great Lakes/Upper Midwest with strong high pressure around 1035 mb building east from the Northern Plains.  A few showers are possible on Friday throughout our area with mainly dry conditions then expected for Saturday, although a few lake effect rain showers could develop along the South Shore of Lake Superior, mainly affecting the counties of Bayfield, Ashland and Iron in Northwest Wisconsin.  Highs on Friday will be in the 50s with some northern areas possibly holding in the 40s.  Lows Friday Night will be in the 30s to around 40 degrees.

5 Day Forecast for Duluth/Superior

.Tonight...  Mostly cloudy with some clearing developing.  Low 40 to 45.  Wind southeast around 12 mph.

.Wednesday...  Variable cloudiness.  A few showers or isolated thunderstorms developing.  High 62 to 67.  Wind west at 15 to 20 mph.

.Wednesday Night...  Partly to mostly cloudy.  Low 40 to 45.  Wind west at 10 to 20 mph.

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

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

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

.Friday Night...  Mostly cloudy.  Low 35 to 40.

.Saturday...  Variable cloudiness.  High 48 to 53.

Normal High Temperature Today 60 degrees
Normal Low Temperature Today 41 degrees

Tim