Friday, August 13, 2010

8/13/10: Friday's Weather Report

Issued at 8:40 PM CDT, Friday, August 13th, 2010


Local Storm Reports in Eastcentral Minnesota and Northwest Wisconsin from Thursday Evening, August 12th, 2010. Source: NWS Duluth, Minnesota.

*9:00 PM CDT 8/12/10: Thunderstorm Wind Damage. Pine City MN (Pine County) Pine County Sheriff Dispatch reports large tree blocking the Intersection of Knob Road and Rolling Hills Road.

*9:00 PM CDT 8/12/10: Thunderstorm Wind Damage. 7 miles West-Southwest of Pine City MN (Pine County) Power lines down near the Grasston area. Trees down blocking Highway 70 and County Road 1.

*9:33 PM CDT 8/12/10: Thunderstorm Wind Damage. 4 miles West of Danbury WI (Pine County) 3" diameter trees down.

9:40 PM CDT 8/12/10: Thunderstorm Wind Damage. Siren WI (Burnett County) Sporadic trees down across county.

9:56 PM CDT 8/12/10: Thunderstorm Wind Damage. Danbury WI (Burnett County) Power lines down.

10:23 PM CDT 8/12/10: Thunderstorm Wind Damage. Minong WI (Washburn County) Washburn County Sheriff reports trees down in Minong.

2:53 AM CDT 8/13/10: Non-thunderstorm wind gust of 45 mph. Pine River MN (Cass County)

Here are some rainfall totals in Northwest Wisconsin and Eastcentral Minnesota from Thursday Night, August 12th, 2010. Source: NWS Duluth, MN.

10 miles South-Southeast of Superior WI (Douglas County) 2.35"

Trade Lake WI (Burnett County) 3.50". Some road washouts. Trade Lake water level is rising and the Trade River is at bankful.

1 mile South-Southwest of Grantsburg WI (Burnett County) 2.48"

2 miles Northwest of Stone Lake WI (Washburn County) 1.31"

11 miles West-Northwest of Spooner WI (Burnett County) 2.20"

1 mile Southwest of Hinckley MN (Pine County) 4.20"

6 miles West of Sandstone MN (Pine County) 1.65"

3 miles North-Northeast of Siren WI (Burnett County) 2.30"

8 miles West of Trego WI (Washburn County) 1.50"

8 miles West-Northwest of Minong WI (Washburn County) 1.85"

Here are some additional rainfall reports across Northern Minnesota and Northwest Wisconsin from Thursday Night, August 12th, 2010. Source: NWS Duluth, MN.

Duluth MN: 0.57"

Brainerd MN: 0.89"

Ashland WI: 0.76"

Hayward WI: 1.31"

4 miles East of Island Lake MN: 0.43"

Bruno MN: 1.00"

12 miles North of Isle MN: 0.98"

Floodwood MN: 0.49"

5 miles Southwest of Brainerd MN: 0.76"

Madeline Island WI: 0.42"

5 miles Northwest of Washburn WI: 0.45"

Gordon WI: 1.28"

Butternut WI: 0.40"

Gurney WI: 0.48"

Sarona WI: 1.21"

Tornado reports Thursday Evening (8/12/10) in Western Minnesota. Source: Storm Prediction Center.

*5:52 PM CDT 8/12/10: Tornado. 1 mile South-Southwest of Louisburg MN (Lac Qui Parle County)

*6:05 PM CDT 8/12/10: Tornado. Bellingham MN (Lac Qui Parle County)

*6:22 PM CDT 8/12/10: Tornado. 1 mile North of Louisburg MN (Lac Qui Parle County)

*6:24 PM CDT 8/12/10: Tornado. 3 miles West of Dawson MN (Lac Qui Parle County)

Note: An additional 5 reports of tornadoes occurred This Afternoon in far Southern-Southeastern Minnesota.

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

A complicated convective set-up was certainly in place during the past 24 hours across our local area. An area of extreme instability which was over Iowa and portions of Southern Minnesota/Eastern South Dakota on Thursday never was able to push this far north, but enough instability was in place around our area, and that combined with plenty of upper level support in the form of a couple of disturbances in conjunction with an upper level trough shifting east into the Upper Midwest along with several weak surface boundaries led to the formation of shower/thunderstorm complexes which targeted Southern parts of our area, or generally along and south of a line from Bemidji to Silver Bay Minnesota from Thursday Night into Today. Numerous reports of wind damage occurred from these fast moving lines of thunderstorms as they tracked through Central-Eastern Minnesota and Northwest Wisconsin last night and Today. Extremely heavy rainfall also occurred due to the high levels of moisture in the air, in fact rainfall totals per Duluth Doppler Radar have been as high as 2-6" from Pine County Minnesota, east through most of Northwestern Wisconsin. This led to some flooding last night and Today. As of This Evening, the threat for heavy rainfall/severe weather has been shifting south/east out of Northwest Wisconsin as a surface trough pushes into Northcentral Wisconsin. A weak cold front continued to move east through the Western half of Minnesota early This Evening, but no precipitation was occurring near that boundary.

High temperatures across our area were in the middle 70s to lower 80s Today with partly sunny-overcast skies. Dewpoints were in the 60s and 70s with winds out of the south, east or north around 20 mph or less.

This Evening's Upper Level Analysis:

Upper level trough number one was pushing E-NE across the Upper Midwest/Western Great Lakes/Western Ontario Province This Evening per water vapor satellite imagery while a second and more potent upper level trough digs south-east into the Northern Rockies.

Rest of Tonight:

Skies will become partly cloudy in Northern Minnesota and Northwest Wisconsin with areas of fog. Any lingering showers or thunderstorms will end by 11 PM in Iron/Price Counties Wisconsin. A weak cold front will pass through our area for the rest of Tonight, but no additional rain is expected as that front moves through. Lows Tonight will be in the 50s and 60s with winds out of the southwest under 15 mph.

Saturday and Saturday Night:

A vigorous upper level trough will move from the Northern Plains to the Upper Midwest during this period while a new cold front takes shape while pushing south/east through the Upper Midwest. Enough moisture should be in place (dewpoints from 58-65 degrees, PWS around 1.00") along and ahead of the front/upper trough to produce a risk for scattered showers in Northern Minnesota and Northwest Wisconsin from mid or late Saturday Afternoon into Saturday Night. There is also a risk for thunderstorms during that same time period as CAPES climb to around 1000 j/kg while Lifted Indices decrease to around zero/-3 degrees C. Severe potential looks low at this point because of the limited instability, but a strong mid level jet from the SW at 40-60 knots combined with an upper level jet >70 knots will push into the Upper Midwest on Saturday which could result in a few stronger storms that would be capable of producing damaging winds late Saturday Afternoon or Saturday Evening...Right now this threat looks greatest along and east of a line from Hinckley Minnesota to Bayfield Wisconsin.

Partly-mostly cloudy skies are forecast Tomorrow and Tomorrow Night with highs in the 70s and 80s with lows generally in the 50s. Winds during this period will be out of the southwest or west at 10-25 mph.

Extended Forecast:

A cooler and less humid weather pattern will take over across the Upper Midwest from Sunday through next Tuesday as a strengthening upper level low passes east through Central Canada while a northwest flow aloft develops over the Upper Midwest. A few showers can't be ruled out from time to time from late this weekend into early next week, especially in Northern Minnesota. High temperatures will be in the 60s and 70s with lows in the 40s and 50s for Sunday and Monday.

5 Day Forecast for Duluth/Superior


.Tonight... Partly cloudy with areas of fog. Low 60 to 65. Wind southwest around 12 mph.

.Saturday... Partly to mostly sunny. Late Afternoon showers or thunderstorms possible. High 80 to 85. Wind southwest to west at 15 to 20 mph. Chance of rain 20%.

.Saturday Night... Showers or thunderstorms possible during the Evening. Variable cloudiness. Low 55 to 60. Wind west at 10 to 20 mph. Chance of rain 40%.

.Sunday... Partly sunny. High 70 to 75.

.Sunday Night... Partly to mostly cloudy. Low 50 to 55.

.Monday... Variable cloudiness. High 65 to 70.

.Monday Night... Partly cloudy. Low 47 to 52.

.Tuesday... Partly sunny. High 65 to 70.

Normal High Temperature Tomorrow 75 degrees

Normal Low Temperature Tomorrow 54 degrees