Cold deepens; Friday snow chance trending south

Arctic cold front sweeps south Wednesday

Snowy dusting possible with frontal passage

-6 forecast low temp in the metro Thursday morning

1st sub zero reading this winter?

January 18th - current latest sub zero on record at MSP

0 number of winters without a sub zero temperature in the metro

3" to 6" model snowfall range for southern Minnesota Friday

Weather forecasting is looking through the windshiled at what's ahead

Climate is what you see in the rearview mirror

"Information is not knowledge." - Albert Einstein

"Technology" is a fancy word for "tool."

The art of weather forecasting:

As we head into a potentially snowier weather pattern, I'm reminded and humbled that forecasting snowfall is among the most difficult forecasts a meteorologist has to make.

It's also one of may all time favorite things to do.

There's a lot of weather information out there. In fact there may be too much weather information, and not enough really good weather information.

There are at least 21 different forecast modles that are put into "ensembels." The reality? Most of them are wrong to some degree on precise forecasting of geographic coverage and snowfall totals.

Sometimes a forecaster is better off just using one or two modles, and knowing their biases.

Food for thought as we head into what passes for our snowy season in Minnesota this winter.

Cold deepens:

You can feel it in the air. This cold is slowly strengthening it's grip on Minnesota.

Ground? Frozen solid. Mild sunny day in the 40s and 50s? Not anytime soon.

This will be bone chilling, tree cracking cold. It's what we expect each winter in Minnesota.

Sub Zero Thursday:

All indications are we'll set a new record for the latest sub zero reading on record Thursday morning, January 19th, 2012.

It could be close Wednesday as temps make a run at zero overnight tonight and again before midnight Thursday.

Any chance that we'll see a winter without sub zero temps has left the building.

More from the Twin Cities NWS & MN Climate Working Group:

Will the Twin Cities Tie a Record for the Latest Below Zero Temperature?

"The likelihood of witnessing a below zero temperature across southern Minnesota and west central Wisconsin during any given winter is very good indeed. There has NEVER been a winter where temperatures failed to drop below zero.

In the Twin Cities, the least number of below zero days was 2 back in the winter of 2001-2002. As of January 16th, the temperature has not dropped below zero at Minneapolis/St. Paul International Airport this winter. January 18th is the latest date during the winter season that the Twin Cities has experienced its first below zero temperature (back in 1889).

In addition, Mankato has yet to see a temperature below zero this winter as of January 16th. The least number of below zero days for a given winter in Mankato was 6 back in the winter of 1982-1983.

St Cloud, Albert Lea and Eau Claire have already seen below zero days this winter. As of January 16th, St. Cloud. Eau Claire, and Albert Lea have all dropped below zero 2 times.

A seasonable cold snap will affect the region through Saturday morning. This could bring below zero readings to portions of the area that haven't seen sub zero temperatures yet this season.

If the temperature at the Minneapolis/St. Paul International Airport drops below zero Wednesday morning (January 18th), it will tie the latest sub zero reading on record (since 1871).

If not, a new "latest subzero reading" will likely be set the following morning (January 19th). Low temperatures are forecast to be close to zero at the airport Wednesday through Saturday morning."

Speaking of the Minnesota Climate Working Group, let me take a moment give thanks and appreciation for the excellent work they do. This dedicated group of professionals keeps the books for a vast variety of Minnesota weather records. The incredibly detailed data is valuable to so many sectors of our economy. You can count agriculture, commerce, tourism and of course media outlets among the many who benefit from their work.

Spend a few minutes (or hours!) sifting through this vast treasure trove of data. You'll see why it's one of my favorite resources for Updraft and our daily weather chats on MPR!

Snowy Friday?

Here's a 72 hour heads up that we could see significant snow in southern Minnesota Friday.

Two of our primary forecast models (GFS and NAM) bring in a snow system Friday.

Early indications are the heaviest snow band could lay out south of the metro, but the metro could see plowable snow Friday if current model tracks hold.

The system appears to have the potential for dumping 3" to 6" of fresh snowfall. Now where that will fall is the big question. It's too early to pinpoint metro totals, but stay tuned as a more active snow pattern kicks into high gear.

You may want to fire up the snow blower, dig the shovel out of the back of the garage and stock up on driveway salt.

I'm just sayin'!

PH