Issued at 3:35 PM CDT, Friday, July 29th, 2011
*6th WARMEST JULY TO DATE AT DULUTH, MINNESOTA*
Source: NWS Duluth, MN.
6th warmest July to date at Duluth, Minnesota. Through July 28th, the average temperature is 69.6 degrees.
Warmest July thru the 28th: 71.7 degrees in 2006
2nd warmest: 71.4 degrees in 1921 and 1881
4th warmest: 70.7 degrees in 1936
5th warmest: 70.4 degrees in 1878
6th warmest: 69.6 degrees in 2011
-Isolated showers/thunderstorms for Southern areas Tonight
-Severe risk Saturday-Saturday Evening
-Dry push for most areas on Sunday
-Next threat for showers/thunderstorms occurs early next week
Forecast Discussion for Northeast Minnesota and Northwest Wisconsin
A weak boundary was over Central Minnesota Today and a few showers and thunderstorms have been developing at times near that front from Central Minnesota to Northwest Wisconsin while Northern areas have stayed dry. Partly to mostly sunny skies covered our area Today with high temperatures generally in the lower to middle 80s with dewpoints ranging from the low 50s in the Arrowhead to around 60 degrees elsewhere. Winds Today were out of the west or southwest under 20 mph.
Today’s Upper Level Analysis:
A near zonal flow (west-east) was in place over the Upper Midwest while a large upper level high pressure ridge continues to bake areas from the Rockies through the Central-Southern U.S. into the Eastern U.S. per RUC model analysis.
Isolated showers or thunderstorms are possible before 10PM, especially along and south of a Brainerd to Moose Lake to Butternut line. Severe weather is not expected This Evening, but brief downpours and occasional lightning strikes are a possibility. The rest of Tonight should be dry in our area with lows in the 50s and 60s. Winds will be out of the south, west or east under 15 mph.
Saturday and Saturday Night:
S-SW 850mb jet of around 30 knots will develop in our area on Saturday out ahead of a southeastward moving cold front. Moisture and instability will both be on the increase ahead of this boundary with dewpoints getting into the 60s to around 70 degrees with PWS of around 1.25″. CAPE is forecasted to reach the 1500-3500 j/kg range with Lifted Indices from -3 to -8 degrees C. A strong disturbance will track east, but stay well to our northwest during this period but the southern flank of the energy off that disturbance coupled with the cold front approaching the Upper Midwest should result in the formation of scattered showers and thunderstorms across Northern and Eastern Minnesota and Northwest Wisconsin especially from Saturday Afternoon into Saturday Evening.
Wind shear will be present ahead of this front with around 30-40 knots of 0-6 KM and EFFECTIVE BULK SHEAR while SW winds at 850mb turn W-NW at 500mb. A 90 knot jet streak will be located to our northwest, around the Manitoba Lakes region with a 60 knot jet streak off to our southwest in South Dakota. 1KM Helicity is forecast to be around 150 m2/s2 Saturday Afternoon-Evening with 1KM EHI values of around 1-2.
There is a threat for some severe thunderstorms Saturday Afternoon and Evening across most of the area with large hail and damaging wind being the main threats along with locally heavy rainfall and dangerous lightning. The tornado potential is fairly low, although one can’t be ruled out especially in Northcentral Minnesota late Saturday Afternoon or early Saturday Evening.
Highs Tomorrow will mainly be in the 80s with lows Tomorrow Night in mainly in the 60s. Southwest winds are expected on Saturday with southwest or northwest winds Saturday Night…Wind speeds during this period will be at or less than 20 mph.
Cold front should clear Eastcentral Minnesota and Northwest Wisconsin Sunday Morning, this boundary will then stall out somewhere in Southern or Central Minnesota for Sunday Afternoon into early Monday. A push of drier and more stable air will move into our area behind this cold front and this should keep our area dry for Sunday and Sunday Night with the threat for showers/thunderstorms staying south of our area. Highs on Sunday will be in the 70s and 80s with dewpoints dropping into the 50s for most areas. Lows Sunday Night will be in the 50s and 60s. Another cold front looks to pass through the Upper Midwest sometime early next week, in the Monday Night-Tuesday time frame. A round of showers and thunderstorms may accompany this system for early next week.
5 DAY FORECAST FOR DULUTH/SUPERIOR
.Tonight… Partly cloudy. Low 60 to 65. Wind west at 10 to 15 mph, becoming southeast.
.Saturday… More humid. Partly sunny. Showers and thunderstorms possible. High 82 to 87. Wind south to southwest at 10 to 20 mph. Chance of rain 50%.
.Saturday Night… Humid. Showers and thunderstorms possible. Mostly cloudy. Low 62 to 67. Wind southwest at 10 to 20 mph becoming west Overnight. Chance of rain 60%.
.Sunday… Partly sunny. Less humid. High 80 to 85.
.Sunday Night… Mostly clear. Low 58 to 63.
.Monday… Partly cloudy. High 77 to 82.
.Monday Night… Showers or thunderstorms possible. Mostly cloudy. Low 60 to 65. Chance of rain 30%.
.Tuesday… Showers or thunderstorms possible, mainly early. Mostly cloudy. High 80 to 85. Chance of rain 30%.
Normal temperatures for Today
High: 77 degrees
Low: 56 degrees
Saturday’s Pollen Forecast:
Sunrise Tomorrow: 5:46 AM CDT
Sunset Tomorrow: 8:43 PM CDT