Winter Storm Warning: 1″ to 2″ tonight; 3″ to 8″ Saturday night & Sunday

-Update 10pm Friday-

A few metro snow totals now trickling in.

MPX: Lakeville [Dakota Co, MN] trained spotter reports SNOW of M1.2 INCH at 09:30 PM CST --

-Updated 6:30pm Friday-

PRELIMINARY LOCAL STORM REPORT

NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN

612 PM CST FRI DEC 07 2012

0600 PM SNOW WINTHROP M1.0 INCH

SIBLEY CO, MN TRAINED SPOTTER

STILL SNOWING. VISIBILITY ABOUT TWO MILES.

Two snow systems for Minnesota next 48 hours

System #1 Tonight 1" to 2" in metro ending late tonight

Rush hour snow affected PM rush in some areas

MNDOT trafic cam at I-35 & Co. Rd. 42 show snow & slick highways in south metro

Image: MNDOT

-Latest Twin Cities radar loop

1st snowflakes have arrived at weather lab in west metro. Expect snow coverage increase in metro next 1-2 hours. twitter.com/MPRweather/sta...

— MPR Weather (@MPRweather) December 7, 2012

Image: Caltech

System #2 Bigger winter storm for most of Minnesota Saturday night & Sunday

3" to 8" likely in the metro by Sunday evening

6" to 12"+ likely for much of northern Minnesota by Sunday night

Winter Storm Warning includes most of Minnesota from Morris to the metro into northern Minnesota

-Twin Cities NWS multimedia briefing here

Image: Twin Cities NWS

Here comes "winter"

Finally.

The season's 1st major winter storm will roll into Minnesota with significant, even heavy snow Saturday night & Sunday.

The appetizer rolls in Friday PM & evening.

Here's the latest on the 2 systems.

System #1) The first snow system is favoring the southern half of Minnesota, basically from the metro south to the Iowa border.

Light to moderate snow is moving in from South Dakota, where visibilities have dropped as low as 1/2 mile at times. Snow will overspread the metro this afternoon, and may be a factor for PM rush hour, especially the tail end and tonight.

A general area of 1" to 2" is likely, with some 3" totals possible south of the metro.

Most of the snow should end by midnight.

System #2) Season's 1st Winter Storm for metro & much of southern Minnesota.

We've been talking about snow this weekend for a week in the weather lab. The models really locked onto growing snowfall totals Thursday, and by last night's (0z) run it was clear we had a significant winter storm approaching Minnesota.

Here's a breakdown of the weekend system.

System: A fairly strong "inverted trof" of low pressure moving in from the Pacific Northwest.

Timing: Snow should begin in western Minnesota by 6pm Saturday, and spread east into the metro between 9pm and midnight.

Duration: Snow should last in the metro until about noon Sunday. That would be aboue 12 to 15 hours of snow of varying intensity.

Moisture: Various models are printing out between .28" (Euro) to .53" (GFS) to .60" (NAM)

Snowfall Totals: The models estimate about a 13:1 snow:liquid ratio with this system. That would translate to an overall snowfall range of 3" to as much as 8" for the metro. I think most of the metro may end up between 3" and 6"...with the best chance of 7" to 8" in the north metro.

Image: Iowa State University

The heaviest snow with this system will be north of the metro. I could see 6" to 12" including St. Cloud, Brainerd, Iron Range, Duluth and the North Shore by Sunday evening.

There's still some time and a few more model runs before Saturday's snow event...and thing could still change. At this point it looks like we'll see a nice coating of white around here by Sunday PM.

We're big boys and girls and used to snow in Minnesota, but this will be the first big snow for the metro so do expect some slick roads and snow covered travel this weekend.

Let it snow!

PH