Duluth: Blizzard… Metro: Rain & thunder, then snow

Update 12:15 am:

Radars show bands of showers and embedded T-Storms moving northeast through southern Minnesota. Expect heavy rain, lightning and thunder, and possible hail as the storms move through early this Tuesday morning.

The late model runs are cranking out an incredible 1.84" liquid precip for the Twin Cities with this storm. Most will fall as rain Tuesday, but indications are about .41" could fall as wet snow Wednesday. That could translate into 2" to 4" of wet slushy snow by late Wednesday in the metro.

Late night NAM Cobb method yields 2" to 4" snowfall totals for Metro Wednesday. (Click to enlarge)

Stay tuned.

-Latest Twin Cities radar loop

PH

***Original post 5:35pm Monday***

After a pretty quiet month, the March Lion is set to roar.

A hybrid winter/spring storm looks like it will roar the loudest from North Dakota through northern and central Minnesota into northern Wisconsin. A combination of heavy snow and wind Tuesday night and Wednesday will slam cities and towns including Grand Forks, Fargo, Bemidji, Brainerd, Duluth, Hinckley, Hayward and Rice Lake.

Winter storm warnings are flying for North Dakota, central and northern Minnesota, and northern Wisconsin. Blizzard warnings have been hoisted for Duluth and the North Shore.

The system:

Low pressure is spinning out of the Rockies headed for the Upper Midwest Tuesday. This a good track to bring heavy precip to Minnesota.

Low track across Iowa. (Click to enlarge all graphics)

Thermal profile:

The storm is forecast to track east through Iowa. Milder air with this hybrid winter/spring system will mean the initial waves of precip Tuesday will be mostly rain. As colder air filters in Tuesday night & Wednesday, precip will change over to snow from north to south.

It looks like most of the precip will fall as snow in Brainerd and Duluth (mixing with rain to start), and most will fall as rain ending with some wet snow in the metro.

Timing:

Expect waves of rain to move in after midnight into Tuesday morning and continue on and off as the changeover to snow occurs Tuesday night into Wednesday from north to south.

Thunder?

There could be enough rising air, what meteorologists like to call "upward vertical velocity"... to produce a few thunderstorms Tuesday, especially afternoon & evening.

Severe risk?

SPC has included southwest Minnesota in a slight risk for severe weather. This is the first time this year any part of Minnesota has been included in a severe risk area.

[image]

Welcome to spring.

Rain & Snowfall totals:

The system should deliver widespread rain to southern Minnesota and heavy snow up north.

The NAM model is cranking out as much as 1'+ for the metro and points north.

The band of heaviest snow appears to be setting up from Fargo through Brainerd to Duluth. It looks like 6" to 12" of wet wind driven snow may fall in the heavy snow band. Areas around Duluth could see 12"+!

At this point, I think 1" to 3" of wet slushy snow could fall in the metro Wednesday. The best chance fo 3" will be in the norhtern suburbs.

Flood impacts:

An inch or more of rainfall will have an impact on rising rivers. NWS Hydrology has factored this in to the latest set of river forecasts Monday, and the latest forecasts are here.

Overall most river forecasts were raised between 1 and 2 feet later this week into the weekend.

Stay tuned as our next storm moves into Minnesota.

PH