Updraft: March 9, 2013 Archive

March Madness for meteorologists: rain, freezing rain, snow

Posted at 6:16 AM on March 9, 2013 by Craig Edwards (0 Comments)
Filed under: Forecast models, Freezing rain, Winter storms

Making the transition from winter to spring is about as smooth as a drive down a road pitted with potholes.

A surge of precipitation was tracking through southern Minnesota at daybreak and will be mainly rain in southeast Minnesota, but will transition to snow and freezing rain in northwest Minnesota and the eastern Dakotas. Northeast Minnesota is the most likely to receive accumulating snow.Track the wintry forecast from Duluth at this storm update website.

NOAA's forecast for the probability of snow accumulating six inches or more by 7 a.m. CDT Sunday.

Source:NOAA NCEP

NWS Warnings and Advisories for today into this evening are shown below. Pink shaded area is a warning for freezing rain changing to accumulating snow. The blue shaded area is a winter weather advisory for ice accumulation this morning. The forecast remains a work in progress.

The discussion from National Weather Service meteorologists this morning from the Chanhassen Office included this comment about the confidence of ice accumulation in the area of central Minnesota under a winter storm warning:

THE WINTER STORM WARNING IS QUESTIONABLE AT THE MOMENT. THERE IS FREEZING RAIN OCCURRING IN THE NORTHWEST PERIPHERY...WITH ONE TO TWO TENTHS OF AN INCH OF ICE POSSIBLE. THEN SNOW COMES IN THE AFTERNOON/EVENING. WILL LEAVE THIS WARNING RIDE FOR NOW. WILL LIKELY DO SOME ADJUSTMENT TO COVERAGE/TYPE LATER THIS MORNING.

Probability of ice accumulation of a tenth of an inch today from NOAA NCEP.

Today's forecasted maximum temperatures from the National Weather Service show the mercury climbing well into the 30s in southeast Minnesota and into central Wisconsin.

Ice accumulations may make roadways slick for a time this morning in the metro area, but wet roads are likely later this morning and this afternoon.

Travel with caution as road conditions may vary considerably.

Generous precipitation from the system will put yet another dent in the drought status, although a frozen landscape is likely to result in runoff into ponds, creeks, rivers and lakes. Some minor flooding is possible on roadways due to clogged drains.

This forecast from the NAM sugests the heaviest precipitation will occur through central into northeast Minnesota this afternoon and evening.

Six-hourly precipitation from noon to 6 p.m. CST today.
Source:NOAA/College of Dupage

The Twin Cities metro area, at this time, does not appear to be in a region of heavy rain today. But the forecast remains a challenge.

Radar image shortly before 7 a.m. CST displays a break in the precipitation this morning in central Minnesota.

Radar screen capture at 655 a.m. CST. Source:Weather underground.

Over a third of an inch of precipitation fell in St. Cloud and at the Twin Cities International Airport overnight. I measured 0.38 inches of precipitation in Eden Prairie as of 7 a.m. CST

Craig Edwards