Feels like March; winter storm watch begins Sunday evening

This is the second day of our second January thaw.

Friday afternoon highs are expected to reach 40 degrees or higher in much of southern and central Minnesota.

Our average high temperature in the Twin Cities metro area is only 24 degrees this time of year, and our average high temp doesn’t hit 40 degrees until March 13.

Seeing the melting snow might make snow lovers cringe, but flakes are in the forecast late this weekend into Monday.

Minnesota highs are expected to be mostly in the 30s this weekend.

Winter storm watch

There’s the potential for substantial snow Sunday evening through Monday from southwestern Minnesota through the Twin Cities metro area and into western Wisconsin.

A winter storm watch has been issued for those areas:

National Weather Service Twin Cities

Areas of freezing rain and sleet are also possible.

Here are some details of the watch:

URGENT – WINTER WEATHER MESSAGE
National Weather Service Twin Cities/Chanhassen MN
404 AM CST Fri Jan 19 2018

…Heavy snow Sunday night into Monday across Central Minnesota
and northern Wisconsin…

.A winter storm will bring a band of moderate to heavy snow late
Sunday evening. There may be a brief break in the snow early
Monday morning, but snow should increase again by mid morning with
snowfall totals of 5 to 8 inches possible by the time the storm
exits the region Monday evening. At this point, the snow will fall
from Mankato through St Paul Minnesota toward Ladysmith Wisconsin.

A wintry mix with freezing rain is possible south of the heavy
snow band. This could lead to slick roads as well. Winds will be
on the order of 20 to 30 mph which will also cause some blowing
and drifting. The track of the heaviest snow will likely change
as the forecast is updated over the next couple of days, but at
this point be prepared for difficult driving conditions if you
have travel plans across central or southern Minnesota and western
and northern Wisconsin.

MNZ060>063-066>070-073>078-082>084-091-WIZ014>016-023>025-027-
191815-
/O.NEW.KMPX.WS.A.0002.180122T0000Z-180122T2100Z/
Hennepin-Anoka-Ramsey-Washington-McLeod-Sibley-Carver-Scott-
Dakota-Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-
Blue Earth-Waseca-Martin-Polk-Barron-Rusk-St. Croix-Pierce-Dunn-
Chippewa-
Including the cities of Minneapolis, Blaine, St Paul, Stillwater,
Hutchinson, Gaylord, Chaska, Shakopee, Hastings, Redwood Falls,
New Ulm, St Peter, Le Sueur, Faribault, Red Wing, St James,
Mankato, Waseca, Fairmont, Osceola, Rice Lake, Ladysmith, Hudson,
River Falls, Prescott, Menomonie, and Chippewa Falls
404 AM CST Fri Jan 19 2018

…WINTER STORM WATCH IN EFFECT FROM SUNDAY EVENING THROUGH
MONDAY AFTERNOON…

* WHAT…Heavy snow with some mixed precipitation possible. Plan
on difficult travel conditions, including during the morning
commute on Monday. Total snow accumulations of 5 to 8 inches and
minor ice accumulations are possible.

* WHERE…Portions of northwest and west central Wisconsin and
central, east central, south central, southeast and southwest
Minnesota.

* WHEN…From Sunday evening through Monday afternoon.

* ADDITIONAL DETAILS…Winds gusting as high as 25 to 30 mph will
cause patchy blowing and drifting snow.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

A Winter Storm Watch means there is potential for significant
snow, sleet or ice accumulations that may impact travel. Continue
to monitor the latest forecasts and be prepared for difficult
driving conditions if you have travel plans.

The forecast models

Since Thursday, forecast models have shifted the heaviest snow band southward.

The Twin Cities metro area is now included in the prime area for substantial snow.

Here’s the National Oceanic and Atmospheric Administration’s Global Forecast System model for Sunday through Monday evening:

NOAA GFS precipitation rate (mm/hour) Sunday through Monday evening, via tropicaltidbits

The color chart to the right of the loop refers to the precipitation rate (mm per hour), not to the amount of precipitation.

The GFS model shows some double digit snow totals in southern and east-central Minnesota. late Sunday into Monday:

NOAA GFS snow totals from Sunday through Monday evening, via tropicaltidbits

It’s likely to be a wet snow, so the snow to water ratio could be closer to 7 to 1 than the 10 to 1 ratio used in the snow graphic above.

A 7 to 1 ratio would lower the snow totals.

Snow amounts in southeastern Minnesota are especially tricky to forecast with this storm, since warm air might keep the southeast in rain or a mix of rain/freezing rain and snow Sunday night followed by a changeover to mostly snow on Monday.

Here’s the snowfall generated in the latest run of the Canadian forecast model:

Canadian GEM forecast model snow totals Sunday through Monday evening, via tropicaltidbits

The Canadian model has also shifted the heavy snow band southward since yesterday.

The latest run of the European Centre for Medium-Range Weather Forecasts (ECMWF) model gives the Twin Cities about one-half inch of precipitation late Sunday through Monday:

ECMWF forecast for Minneapolis, via Norwegian Met Institute

Here’s the conversion of those 13.4 millimeters of precipitation to inches:

With about one half inch of water in the snow, it would translate to about 5 inches of snow if you use a 10 to 1 snow to water ratio.

Don’t be alarmed by the temperatures in the European Centre forecast, they’re in degrees Celsius.

We’ll monitor changes in the forecast models and give you updates as we get closer to Sunday evening.

Updated weather information can be heard on the Minnesota Public Radio Network, and you can read about weather updates on the MPR News live weather blog.

Snow deficit

Minneapolis-St. Paul International Airport has recorded only 12.9 inches of snow this snow season:

NWS Twin Cities

Our official Twin Cities snow total is running 16.1 inches below our average to this point in the season.

NOAA’s snow depth map shows very little snow on the ground in west-central and southwestern Minnesota:

NOAA

Snow lovers will appreciate the fresh blanket of snow that’s expected from Sunday evening into Monday.

There’s already plenty of snow on the ground in northern Minnesota.

Programming note

You can hear my live weather updates on Minnesota Public Radio at 7:49 a.m. Thursdays and Fridays, and at 7:35 a.m., 9:35 a.m. and 4:35 p.m. each Saturday and Sunday.