/Issued 4:44 PM CDT, Thursday, April 30, 2015/
Average number of tornadoes during the month of May (1989-2013)
Source: National Weather Service; Storm Prediction Center
Minnesota: 6
Wisconsin: 3
*Drought Update as of April 28, 2015*
Source: Climate Prediction Center
Minnesota:
*31% of the state is now in Severe Drought (D2) This is up from 0% last week.
*92% of the state is in Moderate Drought (D1) This is slightly higher than last week.
Population affected by drought: 4,976,928.
Wisconsin:
*48% of the state is in Moderate Drought (D1) This is unchanged from last week.
Population affected by drought: 1,728,588.
Drought severity index ending April 25, 2015
Source: Climate Prediction Center
Anywhere from 2-4″ of rain is needed to end the drought across the Western half of Minnesota.
7-day rainfall forecast valid through Thursday, May 7, 2015. Source, Weather Prediction Center. Still seeing a wetter signal showing up in the long range models with potential for 1.00″+ rain totals in Minnesota and Wisconsin by late next week.
Not a lot of rain with Friday’s cold front as rain totals stay below a quarter inch here in the Northland. Source, 12z WRF-ARW model; TropicalTidbits.com
May climate normals for Duluth, Minnesota – Airport location
Temperature: 51.4 degrees
Precipitation: 3.23″
Snowfall: 0.4″
Astronomical data for May:
Sunrise on the 1st: 5:54 AM CDT
Sunrise on the 31st: 5:19 AM CDT
Sunset on the 1st: 8:18 PM CDT
Sunset on the 31st: 8:53 PM CDT
Weather Summary for April 30, 2015
Location: Northeast Minnesota and Northwest Wisconsin
An upper level low was over the Ohio Valley Today while a cold front tracks east through the Northern Plains, in between these systems was an area of high pressure which covered the Great Lakes and Ontario. We saw mostly sunny to partly sunny skies in the Northland Today with high temperatures ranging from the 40s and 50s near Lake Superior with 60s elsewhere, a few spots in far Western parts of the area even made it into the low 70s. Winds Today were out of the south or east at 5 to 15 mph.
Forecast Discussion for Northeast Minnesota and Northwest Wisconsin
Short Term Forecast – Confidence: Medium to High.
Tonight (April 30)
A cold front will move slowly east out of the Dakotas Tonight. Partly to mostly cloudy skies will be found here in the Northland with a chance for showers mainly after Midnight in Western areas. Low temperatures will be in the 30s and 40s with south or east winds at 5 to 15 mph.
Friday and Friday Night (May 1)
Cold front washes out as it moves east/southeast through the Upper Midwest on Friday — Showers are possible in our area as this boundary approaches, the better chance for a shower looks to be before mid Afternoon Friday with just a slight chance for a lingering shower late Friday Afternoon-Evening.
High temperatures on Friday are tricky and will depend a lot on cloud cover. Right now it looks like most areas will top out in the 50s and 60s with cooler temperatures closer to Lake Superior, however, if clearing becomes more widespread than currently forecast, then temperatures could climb above 70 degrees. Low temperatures Friday Night will be in the 40s and 50s. Winds will generally be out of the south or southwest this period at 10 to 15 mph.
Extended Forecast – Confidence: Medium.
Saturday through Monday (May 2-4)
Saturday still looks dry for most of the Northland but a shower can’t be ruled out in far Northern Minnesota. High temperatures should climb into the 70s but it will be cooler along the North Shore of Lake Superior. Lows Saturday Night will be in the 40s and 50s.
Note: The south/southwest wind doesn’t look particularly strong in the Twin Ports on Saturday, so this may allow a lake breeze to develop below the hill in Duluth and Superior, if that happens then it will be a lot cooler near the immediate lakeshore, but should we see the S-SW wind win out, then will have no problem getting into the 70s in Downtown Duluth and in Superior on Saturday.
Another cold front approaches from the west/northwest for Saturday Night and Sunday. This front looks a bit stronger than the one that moves through on Friday.
The computer models generally agree on the best combination of instability and moisture setting up south/southeast of the Northland on Sunday, but we could still have CAPE values of around 500 j/kg and Lifted Indices down around 0 to -2C especially in East Central Minnesota and Northwest Wisconsin Sunday Afternoon — Dew points in the 50s, and CAPE possibly topping 1000 j/kg are forecast to develop across much of Southern Minnesota into Western Wisconsin Sunday PM and that is where the greatest chance for thunderstorms appears to be, and a few of those storms could be on the strong side. Closer to home, there is a chance for showers and a few thunderstorms on Sunday.
Note: Timing of the frontal passage could change a bit between now and Sunday. If it slows down a bit, then the amount of instability and moisture would likely end up higher in parts of the Northland compared to what the computer models are showing Today. This in turn would lead to a better chance for thunderstorms and possibly a few strong storms in parts of our area.
High temperatures on Sunday are forecast to be in the 60s and 70s, but a few 80s are even possible in Eastern Minnesota and Northwest Wisconsin if we see more sun than clouds for most of the day which doesn’t look very likely right now. Low temperatures Sunday Night will be in the 40s and 50s.
Long Range Forecast – Confidence: Medium.
(May 5-10)
Tuesday (5th) looks dry; after that will have a risk for some rain from the 6th-8th as low pressure and an upper level trough push northeast out of the Rockies and Central Plains. Near to above average temperatures are forecast from the 5th-10th.
5 DAY FORECAST FOR DULUTH AND SUPERIOR
.Tonight… Partly cloudy. Low 34 to 39. Wind east to southeast at 10 to 15 mph.
.Friday… Considerable cloudiness. Showers possible especially before Noon. High 57 to 62 but cooler near Lake Superior. Wind south to southwest at 5 to 15 mph.
.Friday Night… Partly cloudy. Low 42 to 47. Wind southwest at 5 to 15 mph.
.Saturday… Partly cloudy. High 70 to 75 but it may be cooler near Lake Superior.
.Saturday Night… Partly to mostly cloudy. Low 50 to 55.
.Sunday… Partly to mostly cloudy. A few showers or thunderstorms possible. High 68 to 73.
.Sunday Night… Partly to mostly cloudy. Low 43 to 48.
.Monday… Partly cloudy. High 60 to 65.
Normal temperatures for Friday
High: 57
Low: 36
Sunrise Friday: 5:54 AM CDT
Sunset Friday: 8:18 PM CDT
Tim