Sunday, June 13, 2010

6/13/10: Sunday's Weather Report

Issued at 6:19 PM CDT, Sunday, June 13th, 2010

Weather History:

On this date in 1987... A record high temperature of 87 degrees occurred at Duluth, MN.

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

Some subtle changes took place Today, the most notable one was that surface winds have shifted to an off-shore direction near Lake Superior, wind speeds were also much calmer Today near Lake Superior compared to what they've been like recently. Otherwise our area continues to be an unsettled pattern with plenty of low level moisture still in place with late day dewpoints mostly in the 50s to around 60 degrees with PWS ranging from 1.00"-1.40" over all but far Northern Minnesota. Some cold air aloft (H5 temperatures -13/-16 degrees C) and pockets of lift across Northcentral-Northeast Minnesota combined with some weak 500 mb height falls (30 meters/12 hours) led to some scattered showers Today with some brief heavy downpours occurring in spots, especially around the Iron Range Cities. Mostly cloudy skies were found across our area Today, but there is some clearing working S-SE into far Northwest-Western portions of our area late Today as some drier air begins to advect southeast from Northwestern Minnesota. High temperatures Today were mainly in the 60s across Northern Minnesota and Northwest Wisconsin with 850 mb temperatures as of 6 PM ranging from +8/+11 degrees C. Winds Today were calm or northerly in direction under 15 mph. Surface map early This Evening featured high pressure of 1020-1022 mb which extended from Southeast Saskatchewan Province south to Wyoming. A stationary front was draped across the Central Plains.

Today's 500 mb analysis:

W/SW flow aloft prevailed across the Upper Midwest Today. An upper level trough covered the Rockies with an 80-100 knot core of upper level winds extending from Northern New Mexico to Eastern Colorado to Western Nebraska per RUC model analysis. A rather potent upper level low was sagging south out of Western Ontario-Eastern Manitoba Province late Today per water vapor satellite imagery. An unusually strong upper level jet of 100-120 knots was found out ahead of this upper low Today from far Northern Minnesota and Northern Lake Superior through Central Ontario Province.

Tonight:

Partly-mostly cloudy skies will be found across Northern Minnesota and Northwest Wisconsin with areas of fog possible later in the night. Scattered showers should end This Evening in Northeast Minnesota and over Southern-Southeast areas of Northwest Wisconsin. Lows Tonight will be in the 40s and 50s with winds either calm or northerly in direction under 12 mph.

Monday and Monday Night:

It appears that most of Monday will be dry across our local area, then rain chances will increase from southwest to northeast by Monday Night as the upper level low off to our northwest Today drops south through the Northern Plains while some moisture streams north into the Upper Midwest out ahead of that feature. Partly-mostly cloudy skies are expected on Monday with highs in the 60s to around 70 degrees but it will be cooler near Lake Superior. Lows Monday Night will be in the 40s and 50s with mostly cloudy skies. Winds during this period will be out of the east at 10-20 mph.

Extended Forecast:

Upper level low will be tracking east-northeast through Minnesota on Tuesday before exiting to our E/NE Tuesday Night-Wednesday. Areas of rain and rain showers will affect most of our area from Tuesday into Tuesday Night as this system moves through. Isolated thunderstorms are also possible Tuesday Afternoon, but the threat for convection is fairly low the way it looks now due to extensive clouds and precipitation which will limit the amount of warmth and instability around our area. Highs on Tuesday will only be in the 50s and 60s with lows Tuesday Night in the 40s and 50s. Note: Areas of fog will likely develop once again near Lake Superior beginning Monday Night and lasting into late Tuesday. Wednesday and Wednesday Night look dry at this time as the upper low from Tuesday exits to our northeast by mid-week while a brief ridge of high pressure builds east into the Upper Midwest behind that system. Highs on Wednesday will be in the 60s and 70s with lows Wednesday Night mainly in the 50s.

Thursday into Friday will see a rather strong area of low pressure push northeast through the Dakotas...Passing well to our northwest late this week. A warm front and cold front attached to this low will push through our area from Thursday into Friday Morning. A 25-35 knot low level jet is forecast to be in place ahead of this system which will bring another surge of low level moisture north into our area. Right now the GFS model has dewpoints surging into the 60s on Thursday across our area with 850 mb td's of +12/+16 degrees C. Instability also looks rather impressive Thursday/Thursday Night across our local area per GFS model with CAPES from 1000-2500 j/kg. There will be a risk for showers and thunderstorms late this week as this storm moves through. If the current model projections hold-up, then there may be a risk for some severe weather across portions of Minnesota sometime Thursday or Thursday Night.

5 Day Forecast for Duluth/Superior

.Tonight... Partly to mostly cloudy. A brief shower possible before 10 PM. Patchy fog late. Low 47 to 52. Wind variable under 12 mph.

.Monday... Partly to mostly cloudy. High 60 to 65 but cooler near Lake Superior. Wind becoming east at 10 to 20 mph.

.Monday Night... Mostly cloudy. Showers possible along with areas of fog. Low 48 to 53. Wind east at 10 to 20 mph. Chance of rain 40%.

.Tuesday... Mostly cloudy. Showers at times. Areas of fog. High 56 to 61. Chance of rain 60%.

.Tuesday Night... Mostly cloudy. Showers at times, mainly during the Evening. Areas of fog. Low 48 to 53. Chance of rain 50%.

.Wednesday... Partial sunshine. High 65 to 70.

.Wednesday Night... Partly cloudy. Low 50 to 55.

.Thursday... Showers or thunderstorms possible. Partly sunny. High 67 to 72. Chance of rain 30%.

Normal High Temperature Tomorrow 71 degrees

Normal Low Temperature Tomorrow 48 degrees

Tim