Sunday, May 14, 2017

Gusty east winds continue tonight near Lake Superior. Showers/T-storms possible late tonight; A few strong-severe storms possible Tue

/Issued 3:03 PM CDT, Sunday, May 14, 2017/

Monday's severe weather outlook.  Source:

Tuesday's severe weather outlook.  Source:

Tonight's low temperature forecast.  Source:

Monday's high temperature forecast.  Source:

Forecast storm track is the black line on map.

Temperature departure map for the week of May 7, 2017.  Source:

Precipitation departure map for the week of May 7, 2017.  Source:

Temperature and precipitation report for Duluth, Minnesota (Airport location)

May 7-13, 2017

High temperatures

5/7:  53 F/-7 degrees below normal
5/8:  56 F/-4 degrees below normal
5/9:  71 F/+11 degrees above normal
5/10:  71 F/+10 degrees above normal
5/11:  65 F/+4 degrees above normal
5/12:  72 F/+11 degrees above normal
5/13:  63 F/+1 degree above normal

Low temperatures

5/7:  32 F/-6 degrees below normal
5/8:  33 F/-5 degrees below normal
5/9:  39 F/Normal
5/10:  44 F/+5 degrees above normal
5/11:  38 F/-1 degree below normal
5/12:  36 F/-4 degrees below normal
5/13:  37 F/-3 degrees below normal

Total precipitation:  Trace
Normal:  0.70"
Departure:  -0.70" below normal

Note:  It's been a while since we had some rain here in Duluth.  May 3rd was the last time with measurable rain (0.01" accumulation)  The last significant rainfall was on May 1st with 0.52".

Weather Synopsis

A much stronger wind off Lake Superior developed today which has kept afternoon temperatures in the mid 40s to mid 50s near Lake Superior while inland locations have warmed into the 60s to lower 70s.  Note:  Even warmer temperatures farther south this afternoon with temperatures in the 80s across the south half of Minnesota.  Low level moisture has been increasing today with dew points in the mid 40s and low 50s in central/southern Minnesota with drier air/lower dew points continuing over most of the Northland today.  There is a warm front which stretches from west central to south central Minnesota this afternoon and this boundary separates the warmer/slightly more humid airmass along and south of it to a drier airmass north of that front.

-The focus for tonight will be that aforementioned warm front which was west/south of the Northland today -- A warm and moist advection pattern will occur in our area tonight (Or to the north of that front) with a fairly weak low level jet ~20 knots helping to advect deeper moisture up into our area with PWATS increasing to 0.70-1.10" during the night.  Elevated instability will also be on the increase tonight with CAPE in the 250-850 j/kg range pushing into our area tonight.  Should see scattered showers and thunderstorms develop across parts of the Northland especially from later this evening and through the overnight hours.  Note:  The potential for severe weather is very low, but a few of the storms could become strong enough to produce small hail along with some lightning and heavy downpours later tonight.

-The warm front Monday will likely get pushed a little more to the south due to the possible convection that forms north of that front tonight.  This warm front is then forecast to slowly lift north/east Monday night and Tuesday.  Additional rounds of showers and thunderstorms are expected to develop along and north of that boundary especially Monday night and Tuesday but a few showers could also develop at times Monday especially over northwest Wisconsin.  Note:  At the moment the greatest chance for any stronger thunderstorms in the Northland looks to be on Tuesday as this is when the greatest instability, favorable winds aloft and strong wind shear sets up across parts of the Northland.  Heavy rainfall is also possible Monday night into Tuesday with the moist airmass in place.

For the Twin Ports of Duluth and Superior

*Stays windy tonight under partly to mostly cloudy skies.  Scattered showers and thunderstorms are possible especially after midnight.  Lows in the lower 40s.  East winds at 15 to 25 mph with higher gusts.

*Mainly dry during the day Monday.  Partly to mostly cloudy.  Not as windy as Sunday but an easterly wind continues at 10 to 20 mph.  High 60 to 65, but 40s and 50s closer to Lake Superior.

Normal temperatures for Monday

High:  62
Low:   40

Sunrise Monday:  5:33 AM CDT
Sunset Monday:   8:37 PM CDT