Tuesday, February 17, 2015

February 17, 2015 Weather Report - Dangerous wind chills/bitterly cold Tonight and Wednesday; Watching Friday's snow chances along with slightly warmer temps late this week

/Issued 4:05 PM CST, Tuesday, February 17, 2015/

Keeping an eye on Friday for a possible light snow event in northeast Minnesota and northwest Wisconsin.  The culprit is a clipper low which is forecast to hug the Ontario/Minnesota border on Friday.  This system should bring widespread light snow to the Northland on Friday, but only minor accumulations are anticipated at this time (Half inch to 2" amounts)

NWS hazards map.  Light blue=Wind Chill Advisory.  More information at this link:  http://forecast.weather.gov/wwamap/wwatxtget.php?cwa=dlh&wwa=wind%20chill%20advisory

Pattern change coming?

The maps below are from the CFS model (12z run from February 17, 2015)  Shown is the temperature anomaly with blues indicating below average temperatures and orange/red colors indicating warmer than average temperatures.  

Look what happens in these two maps.  The first map is valid through February 22.

Note:  Keep an eye on the white circled area.

March 9-14.

Weather Summary for February 17, 2015
Location:  northeast Minnesota and northwest Wisconsin

Arctic air has returned! Skies were partly to mostly cloudy in the area Today with temperatures ranging from around zero to the single digits above.  Winds were out of the west or northwest at 5 to 15 mph with higher gusts.  3 PM weather map featured low pressure of 1006mb over far eastern Ontario with high pressure averaging 1028mb building SSE out of western Saskatchewan.

Forecast Discussion for northeast Minnesota and northwest Wisconsin

Short Term Forecast - Confidence:  High.

Tonight (February 17)

An upper level trough with 500mb height falls of 90-120 meters will continue to settle south into the Upper Midwest Tonight as mid level heights range from around 498-504 meters.  Scattered snow showers and flurries will be found over the area especially before Midnight.  Model guidance has shown weak snow squall parameter values as the upper trough moves overhead Tonight, so there could be a few brief heavier snow showers but they won't last very long.  Snowfall accumulations Tonight should remain less than an inch.  The bigger story will be the cold as low temperatures fall into the single digits, teens, to 20s below zero.  Winds will be out of the west or northwest at 10 to 15 mph.

Wednesday and Wednesday Night (February 18)

Arctic high pressure will build into the Upper Midwest this period.  Clear to partly cloudy skies will be common with highs on Wednesday ranging from around zero to the single digits below.  Lows Wednesday Night will be in the teens and 20s below with 30s below possible in the traditional cold spots.  Winds will be out of the northwest at 10 to 15 mph.

Extended Forecast - Confidence:  High.

Thursday through Saturday (February 19-21)

High pressure moves off to the east on Thursday, expect dry weather with highs in the single digits below to single digits above zero with lows Thursday Night in the single digits, teens, and 20s below.

A low pressure system is forecast to move southeast and track along the Ontario/Minnesota border on Friday before exiting to the east/southeast Friday Night/Saturday.  This system could bring some snow to the Northland on Friday with possible 1-2" accumulations the way it looks now.  Dry weather returns on Saturday.  It will warm up a bit on Friday with highs in the single digits and teens, lows Friday Night will mainly be in the single digits.  Highs on Saturday will be in the single digits and teens.

Long Range Forecast - Confidence:  High.

(February 22-27)

Another shot of arctic air is expected on the 22nd-23rd, followed by possibly another shot sometime around the 24th-25th...But after that it finally looks like the extreme cold will ease up, however temperatures remain below average through the 27th way it looks now.  A light snowfall event is possible around the 23rd-24th.


Timing:  Midnight Tonight until Noon CST Wednesday

.Tonight...  Frigid.  Snow showers and flurries This Evening.  Partly to mostly cloudy.  Low 10 below to 15 below.  Wind west to northwest at 10 to 20 mph.  Dangerous wind chills as low as 35 below developing late.

.Wednesday...  Very cold.  Mostly sunny.  High 2 below to 3 above.  Wind northwest at 10 to 15 mph.  Dangerous wind chills as low as 35 below during the Morning.

.Wednesday Night...  Frigid.  Mostly clear.  Low 13 below to 18 below.  Wind northwest at 5 to 15 mph.

.Thursday...  Mostly sunny.  High 0 to 5.

.Thursday Night...  Partly to mostly cloudy.  Low 10 below to 15 below.

.Friday...  Light snow possible with light accumulations.  Mostly cloudy.  High 11 to 16.

.Friday Night...  Mostly cloudy.  Snow showers or flurries possible.  Low 2 to 7.

.Saturday...  Partly sunny.  High 10 to 15.

Normal temperatures for Wednesday

High:  25
Low:    7

Sunrise Wednesday:  7:08 AM CST
Sunset Wednesday:   5:38 PM CST