Sunday, May 22, 2016

May 22, 2016 - Extreme fire danger today in northeast Minnesota; Keeping an eye on Monday's thunderstorm chances; Future radar for Monday included in this post

/Issued 11:34 AM CDT, Sunday, May 22, 2016/

Fire danger ratings map for May 22, 2016.  Source, MNDNR.

Extreme fire danger across a large part of Minnesota today.

Elevated fire risk in all of the Northland today (Orange shaded area on map)  Source, Storm Prediction Center.

Red Flag Warning in effect through early this evening for northern Minnesota (Pink shaded area on map)  Source,; National Weather Service.

More information at the link below.

Red Flag Warning --

Last week's temperature departure map -- Below average temperatures in all but far northwest Minnesota and around the head of Lake Superior.

Last week was a dry one! This week should be a little wetter.

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

May 15-21, 2016

High temperatures:

5/15:  60 F/-2 degrees below normal
5/16:  56 F/-6 degrees below normal
5/17:  61 F/-2 degrees below normal
5/18:  68 F/+5 degrees above normal
5/19:  70 F/+7 degrees above normal
5/20:  73 F/+9 degrees above normal
5/21:  80 F/+16 degrees above normal

Low temperatures:

5/15:  28 F/-12 degrees below normal
5/16:  37 F/-4 degrees below normal
5/17:  35 F/-6 degrees below normal
5/18:  38 F/-3 degrees below normal
5/19:  40 F/-2 degrees below normal
5/20:  44 F/+2 degrees above normal
5/21:  43 F/+1 degree above normal

Total precipitation:  0.03"
Normal:  0.73"
Departure:  -0.70" below normal

Future radar for Monday, May 23, 2016 per 12z WRF-NSSL model;

The leading edge of the deeper moisture could set off a few showers/thunderstorms in parts of the Northland Monday morning.

New thunderstorm development could take place across central Minnesota Monday afternoon roughly during the 1-3 PM time frame according to the 12z WRF-NSSL computer model.

It will be another day of warm temperatures and low humidity values across the Northland with southerly winds in the 10 to 20 mph range with higher gusts possible during the afternoon-evening hours.  High temperatures today will be in the 70s to lower 80s.

Much cooler temperatures will be found closer to Lake Superior due to a somewhat stronger lake breeze today, high temperatures will likely hold in the 50s and 60s today from Superior to Downtown Duluth and up along the North Shore of Lake Superior -- The wind coming off Lake Superior will also keep the fire danger somewhat lower today along the North Shore due to the cooler and somewhat more humid airmass coming off Lake Superior.

...Looking ahead to Monday's thunderstorm chances in northeast Minnesota and northwest Wisconsin...

A cold front over the northern Plains will move slowly toward the east through Monday.  Moisture will be on the increase out ahead of this front thanks to a strengthening S/SW low level jet of 30-45 knots tonight and Monday morning -- Dew points in our area are expected to climb into the 55-65 degree range on Monday with PWATS well over 1.00" along with 850mb dew points of around +12C or higher.  So we will have the moisture available for convection but other ingredients are not as impressive tomorrow.

-Mid level lapse rates are expected to be at around 6.0 c/km.

-Bulk shear values generally around 20-30 knots (Kinda weak)

-CAPE will generally be in the 500-1000 j/kg range although it is possible that will have pockets of higher instability upwards of around 1500 j/kg but that will depend on how much clearing/heating can take place after Monday morning.

-Low level jet at around 25-35 knots Monday afternoon with mid level winds generally around 30 knots.

-Upper level winds >70 knots over the Red River Valley, a lot of times thunderstorms like to form southeast of where the axis of stronger winds aloft are located so that would put the Northland in a decent location for convection on Monday.

Bottom line:  I do expect scattered showers and thunderstorms in northeast Minnesota and northwest Wisconsin on Monday with lightning and heavy downpours being the primary hazards but small hail and gusty winds will also be possible in the strongest storms.

The potential for severe thunderstorms (1.00"+ diameter hail and or winds of 58 mph or stronger) doesn't look very high for tomorrow but a storm approaching severe levels is certainly possible either Monday afternoon or evening (2 PM-10 PM time frame)