Friday, July 23, 2010

7/23/10: Friday's Weather Report

Issued at 3:46 PM CDT, Friday, July 23rd, 2010

*2 tornadoes reported in Western Minnesota on Thursday, July 22nd, 2010 per Storm Prediction Center.

The first tornado was reported at 5:45 PM CDT, 6 miles Northeast of Bemidji, Minnesota (Beltrami County)

The second tornado was reported at 8:05 PM CDT, 4 miles South of Brandon, Minnesota or west of Alexandria, MN (Douglas County)

Rainfall reports from Thursday, July 22nd, 2010 from Northern Minnesota. Source: NWS Duluth, MN.

Koochiching County:

International Falls MN: 0.91"

Littlefork MN: 1.19"

Cass County:

Cass Lake MN: 0.27"

St. Louis County:

Hibbing MN: 0.14"

Cook MN: 0.43"

Kabetogama MN: 1.04"

3 miles East of Orr MN: 0.94"

Forecast Discussion for Northeast Minnesota and Northwest Wisconsin

Today's Weather:

Low pressure (1002) mb was centered near Thunder Bay Ontario Canada as of mid-Afternoon. A stationary front stretched from Central Wisconsin to Southeast Minnesota to Northern Iowa. This boundary seperates extremely unstable and muggy air along and south of that boundary with much more stable and drier air north of that boundary. Partly-mostly cloudy skies covered our local area Today with high temperatures in the 70s to lower 80s with Afternoon dewpoints ranging from the mid 50s to low 60s with PWS of 0.90"-1.10". Winds Today were out of the northwest or west around 20 mph or less. A secondary area of low pressure (1006 mb) was centered in Southwest South Dakota This Afternoon with a cold front across the Western Dakotas. This next low pressure disturbance has been generating scattered strong-severe thunderstorms Today over portions of Western-Southern North Dakota and Northern South Dakota.

Today's Upper Level Analysis:

(5700 meter) upper level low was centered over far Northeast Montana late Today per water vapor satellite imagery with movement toward the south/east. West-southwest flow aloft was in place over the Northern Plains and Upper Midwest This Afternoon out ahead of this digging upper low/upper level trough. A plume of deep tropical moisture consisting of dewpoints in the 70s to around 80 degrees and PWS from 1.30"-2.30" covered much of the Plains into Southern parts of the Upper Midwest as well as the Central-Southern Great Lakes Today per water vapor satellite imagery, this plume of deep moisture helped trigger the exceptional rainfall totals that led to some serious flooding last night in Milwaukee, Wisconsin.

Tonight:

A warm front will develop well to our south while low pressure heads east out of Southern South Dakota and into Southern Minnesota Overnight. Extremely unstable and tropical air will continue to sit south of our local area Tonight where numerous strong to severe thunderstorms will erupt Tonight with a threat for heavy rain and areas of flooding. In our local area, expect some rain showers spreading from west to east through the night with isolated thunderstorms possible mainly in Southern areas. Partly-mostly cloudy skies will cover Northern Minnesota and Northwest Wisconsin Tonight with lows in the 50s and 60s. Winds will be out of the north, northwest, or east under 20 mph.

Saturday and Saturday Night:

Low pressure with it's warm front and cold front will exit to our south/east early Tomorrow Morning, this will then be followed by the potent upper level low and it's pool of cold air aloft which was over the Northern Rockies This Afternoon, this 500 mb low will reach the Upper Midwest on Saturday and will likely cause scattered showers and isolated thunderstorms across our area. The threat for showers will end across our area Saturday Evening as the upper low starts to exit our area to the east with high pressure starting to build in from the Northern Plains. Partly sunny-mostly cloudy skies are forecast on Saturday with highs in the 60s and 70s. Skies will become partly cloudy Saturday Night with lows in the 50s, but some 40s can't be ruled out in the typical cool spots. Winds during this period will be out of the north or northwest at 10-20 mph.

Extended Forecast:

High pressure moves southeast of our area Sunday and Monday which will cause winds to swing around to the south. Temperatures will warm into the 70s and 80s in Northern Minnesota and Northwest Wisconsin on Sunday with mainly 80s expected for Monday. Lows Sunday Night and Monday Night will be in the 50s and 60s. A cold front will move through our area most likely from Monday Night into Tuesday Night, this boundary combined with a moist and somewhat unstable airmass in place ahead of the front should lead to a risk for a few showers or thunderstorms sometime early next week.

5 Day Forecast for Duluth/Superior

.Tonight... Partly to mostly cloudy. Scattered showers possible, mainly after Midnight. Low 56 to 61. Wind northwest at 5 to 15 mph becoming northeast. Chance of rain 40%.

.Saturday... Considerable cloudiness with scattered showers, isolated thunderstorms also possible. High 70 to 75. Wind north at 10 to 20 mph. Chance of rain 50%.

.Saturday Night... A few showers possible early. Becoming partly cloudy. Low 53 to 58.

.Sunday... Partly cloudy. High 78 to 83.

.Sunday Night... Mostly clear. Low 57 to 62.

.Monday... Partly cloudy. High 82 to 87.

.Monday Night... Partly cloudy. Low 60 to 65.

.Tuesday... Showers or thunderstorms possible. Partly sunny. High 80 to 85. Chance of rain 30%.

Normal High Temperature Today 77 degrees

Normal Low Temperature Today 55 degrees

Tim