Updraft: February 8, 2013 Archive

Monitoring our weekend storm; NYC to Boston to be blasted by blizzard

Posted at 6:37 AM on February 8, 2013 by Craig Edwards (11 Comments)
Filed under: Blizzard, Winter 2012-13

Forecast model disparity continues, but confidence is growing for a major winter storm to take aim at Minnesota, the eastern Dakotas and northwest Wisconsin.

Paul's been talking about the model differences on the track of the low pressure that will determine the locaton in the upper Midwest that is likely to be buried in heavy snow Saturday night and Sunday.

Twenty years ago I would have been more confident about snow in east central Minnesota, but evidence of decadal warming says not so fast. It appears that relatively mild air is forecast to push as far north as the Twin Cities on Sunday morning and produce a wintry mix.

The National Weather Service has already hoisted a variety of Winter Storm Watches for Minnesota and the eastern Dakotas.

As travel from New York City to Boston is brought to a standstill in the next 36 hours, our focus is on the developing storm in the Four Corners area of the southwest US.

IR satellite image from NOAA GOES at 545 a.m. CST

Enhanced clouds/colder cloud tops indicated in blue.

I''ll toss out this text issued out of the Boston NWS Office this morning to give you an idea what is ahead for the folks in the Northeast. Statement issued at 439 a.m. EST.

* ACCUMULATIONS...SNOW ACCUMULATION OF MORE THAN 2 FEET.
* TIMING...LIGHT SNOW WILL DEVELOP BY THIS MORNING...BECOMING
HEAVY LATE IN THE DAY INTO THE EVENING COMMUTE. THE HEAVIEST
SNOW...ESPECIALLY FOCUSED ALONG THE I-95 CORRIDOR... WILL FALL
TONIGHT INTO SATURDAY.

* IMPACTS...BLIZZARD CONDITIONS AND DANGEROUS TRAVEL. WHITEOUT
CONDITIONS ARE ANTICIPATED AS ROADS BECOME SNOW COVERED BY THIS
EVENINGS COMMUTE. STRONG NORTH-NORTHEAST WINDS ARE ANTICIPATED
WITH GUSTS UP TO AROUND 60 MPH...RESULTING IN BLOWING AND
DRIFTING OF SNOW. DAMAGE TO TREES AND STRUCTURES ALONG WITH
SCATTERED POWER OUTAGES ARE ANTICIPATED.

* WINDS...NORTHEAST 30 TO 40 MPH WITH GUSTS UP TO 70 MPH.

The European Model continues to favor a track that has the highest potential to keep the precipitation snow or a snow/sleet and rain mix.

Source:College of Dupage. Model presents surface pressure pattern at 6 p.m. CST Sunday and temperatures around 5 thousands feet in degrees Celsius.

Forecasters at NOAA NCEP project a track that also favors a path through Iowa on Sunday.

Source:NOAA and College of DupageGFS model places the center of the low in southern Iowa on Sunday at 6 p.m. CST with temperatures into the middle 30s in southeast Minnesota.

I examined the vertical profile from the GFS model forecast for Sunday evening and it predicts a cold rain or a wintry mix for the Twin Cities. You'll just have to stay tuned for updates.

NOAA's forecast of snowfall of 8 inches or more on Sunday and Sunday night looks to be a good prediction based on current model data.

Tracking a developing winter storm for the upper Midwest

Posted at 12:37 PM on February 8, 2013 by Craig Edwards (2 Comments)
Filed under: Blizzard, Winter 2012-13, Winter storms

It's tempting to start tossing out snowfall predictions with the weather system forecast to arrive in the upper Midwest Saturday night. Not a single snow flake has yet to form to our southwest, thus I'll stall on predicting snow amounts for a specific location.

There is no reason, at this time, to make adjustments to the forecast reasoning that was posted this morning. The latest model runs still suggest the best chance for the highest snowfall totals to be northwest of the Twin Cities.

The model ensemble tracks for the center of the surface low are clustering in southern Minnesota on Sunday. Heaviest snow most often falls to the north and northwest of the track of the surface low. Temperatures in southeast Minnesota are likely to reach the lower 30s on Sunday. Precipitation could fall as a cold rain in Rochester.

Source:NOAA

Forecasters might be weighing the more southerly track of the European model by placing the red triangle in Iowa, well south of the ensemble output for Sunday. If the European model verifies, the Twin Cities could experience mostly snow, versus a wintry mix.

The National Weather Service has posted a Winter Storm Watch for the Dakotas through much of Minnesota in western Wisconsin for Sunday. Some locations in western Minnesota could experience near blizzard conditions.

Source:NWS

Here's the latest thinking on the probability of snow accumulating 6 inches or more on Saturday night and Sunday from NOAA NCEP/HPC issued Friday afternoon:

Quiet weather is in store through Saturday morning. Travel is likely to become hazardous after dark on Saturday.

Craig Edwards