Thursday, June 23, 2016

June 23, 2016: Pleasant tonight; Back up around 80 with comfy dew points on Friday; 3 weak tornadoes and 1 strong tornado (EF-0 to EF-2) in the Northland this past Sunday

/Issued 8:04 PM CDT, Thursday, June 23, 2016/

Showers and thunderstorms are possible on Saturday -- A few of these storms could be strong to severe across the Northland but how much severe weather we get will depend on the timing of key frontal boundaries as well as the amount of clearing and warming that can occur during the afternoon hours.  Stay tuned!  Source, Storm Prediction Center.

Friday's thunderstorm outlook.  Source, Storm Prediction Center.  Slight risk of severe thunderstorms (Yellow area on map) in much of North Dakota and far northwest Minnesota.

Low temperature forecast for tonight.  Source, National Weather Service Duluth, Minnesota.

High temperature forecast for Friday.  Source, National Weather Service Duluth, Minnesota.

Tornado summary for June 19, 2016 -- Updated as of June 22, 2016
Source:  National Weather Service Duluth, Minnesota

Note:  4 confirmed tornadoes on June 19, 2016 including one strong tornado (EF-2 rating)  The other three tornadoes were weak with an EF-0 to EF-1 rating per NWS.

Tornado #1:  southwest Cass County Minnesota

Rating:  EF-0
Estimated peak wind:  65 mph
Path length:  2 miles, estimated based on reports
Path width:  50 yards
Fatalities:  0
Injuries:  0

Start date:  June 19, 2016
Start time:  6:13 PM CDT, estimated
Start location:  7.5 miles north of Staples, MN

End date:  June 19, 2016
End time:  6:17 PM CDT
End location:  8 miles east-southeast of Staples, MN

Tornado #2:  Placid Lake

Rating:  EF-2
Estimated peak wind:  120 mph
Path length:  3.5 miles
Path width:  730 yards, 0.4 miles
Fatalities:  0
Injuries:  2

Start date:  June 19, 2016
Start time:  7:11 PM CDT
Start location:  2 miles south-southwest of Deerwood, MN

End date:  June 19, 2016
End time:  7:19 PM CDT
End location:  1 mile east-southeast of Bay Lake, MN

Rainfall report for June 22, 2016
Source:  National Weather Service Duluth, Minnesota;

Duluth, MN (Airport)  0.37"
Hibbing, MN:  0.30"
Hayward, WI:  0.99"
3 E of Wright, MN:  0.23"
8 S of Bigfork, MN:  0.17"

Cass Lake, MN:  0.52"
12 N of Grand Rapids, MN:  0.20"
Togo, MN:  0.24"
Duluth, MN (NWS)  0.43"
Floodwood, MN:  0.57"

Butternut, WI:  0.50"
Park Falls, WI:  0.34"
9 SE of Webster, WI:  1.01"
Superior, WI:  0.36"
Cloquet, MN:  0.26"

Saginaw, MN:  0.49"
Two Harbors, MN:  0.15"
Silver Bay, MN:  0.21"
Hill City, MN:  0.65"

Weather Summary for NE Minnesota and NW Wisconsin
Date:  June 23, 2016

A near perfect early summer day under a sunny to partly cloudy sky.  Highs were in the mid 70s to 80 degrees with dew points only in the mid 40s to mid 50s.  Winds today were variable in direction at around 10 mph.

Forecast Discussion for NE Minnesota and NW Wisconsin

Confidence:  High.

Tonight:  Clear to partly cloudy with lows in the 50s to around 60 degrees, a few 40s can't be ruled out in the typical cold spots.  Winds turn to the south/southwest at around 10 mph.  An area of high pressure settles over the Upper Midwest tonight resulting in tranquil weather conditions.

Friday:  South winds develop as high pressure moves over the Great Lakes while low pressure heads into the northern Plains -- A warm front attached to that low will move into western Minnesota by daybreak Saturday.  Mainly dry during the day with highs in the 70s and 80s, just a touch more humid tomorrow with dew points in the 50s to lower 60s.  Showers and thunderstorms are possible late Friday night as a moist advection pattern along with a 30+ knot low level jet develops east of the low pressure system moving into the Dakotas.  Elevated instability will also climb tomorrow night so a few strong to marginally severe thunderstorms can't be ruled out mainly across north central Minnesota.  Lows Friday night will be in the 60s with 50s along the North Shore of Lake Superior.  South or southeast winds are expected at 10 to 20 mph.

...Extended Forecast...

Confidence:  Medium.

An area of low pressure is forecast to deepen from 1001mb to around 992mb on Saturday as it lifts northeast into Manitoba Province.  Attached to this low will be a warm front and cold front, both those boundaries will pass through the Northland on Saturday -- Showers and thunderstorms are expected to develop at times through Saturday evening as this system moves through.  

Note:  A few strong to severe thunderstorms remain possible Saturday in northeast Minnesota and northwest Wisconsin but there is uncertainty on the amount of clearing/heating that can take place during the afternoon, if convection and cloud cover is persistent most of the day, then that would probably mean a lesser chance for severe storms in our area.  Interesting to note that the CIPS analog guidance is targeting central and eastern Minnesota more than northern Minnesota for possible severe weather on Saturday, also the longer range HopWRF model has the greatest severe potential mainly before 5 PM in Minnesota before things shift east into Wisconsin, in other words it might be an early show meaning the afternoon hours would have the greater potential for severe weather (If any develops) compared to the evening hours.  Things will probably change a bit by Saturday so just stay tuned to later updates.

Breezy but still mild weather on Sunday as deep low pressure passes north of Minnesota -- Could be a few showers or thunderstorms during the afternoon-evening.

High temperatures on Saturday will be in the 70s and 80s with cooler temperatures around Lake Superior.  Highs on Sunday will be in the 70s and 80s with 60s in northern Minnesota.

Forecast for Duluth and Superior

Tonight - Mostly clear.  Low 55 to 60.  Wind variable around 10 mph.

Friday - Partly cloudy.  High 76 to 81.  Wind south at 10 to 15 mph.

Normal temperatures for Friday

High:  73
Low:  52

Sunrise Friday:  5:15 AM CDT
Sunset Friday:   9:07 PM CDT