AM model run update 9:30am:
The latest NAM model run Thursday morning cranks out .97" of liquid equivalent for the metro Saturday. That may be high...but if it verifies that would produce in well excess of 9" of snow!
The latest trends indicate this could be a major winter storm with 6" to 12+" snowfall accumulations and winds over 25mph somewhere near the metro Saturday!
It's still early and a lot can change between now and Saturday, but as we say in the weather biz...stay tuned!
The 2010-'11 snow season is off and running with a bang.
Another clipper is racing through Minnesota today. This one is a "mini-clipper" and will bring just nuisance snowfall under an inch (and a little freezing drizzle) to most of southern Minnesota today as it zips along to the east. Northern Minnesota and Wisconsin may see a bit more snow...with 2" to 4" possible north of Hinckley and Duluth, and east into Wisconsin.
Milder today & Friday: Today's weather system will drag some milder air briefly into the Upper Midwest for our mildest temps so far in December. Temps could top out in the lower 30s today...with 20s Friday.
The warmest reading in the Twin Cities so far this December is 25 degrees, back on December 4th.
Next system Saturday:
I don't know what it is about Saturdays in the metro...but 3 of the past 4 weekend have featured a Friday night-Saturday snow system...and it looks like the next two weeks may continue the trend.
The forecast models are spinning up another potent snow system Saturday. The low is forecast to develop ahead of an arctic outbreak, and track into the southern half of Minnesota overnight Friday into Saturday. There is still some question as to how far south the system may track....but it looks powerful enough to crank out a band of 4" to 8"+ (and maybe as much as 10+") in the heaviest snow band.
In some ways this system looks much like the super clipper of last weekend, with the best chance for heavy snow just south of the metro. The metro is still on the northern edge of the system at this time....but stay tuned for forecast updated tonight and Friday for the possibility of heavy snow from the metro south Friday night & Saturday.
Snowiest start to winter in nearly 20 years:
If you think the snow is piling up early, you're right. We've shoveled 16.7" away from our driveways around Twin Cities Airport sine the snow began to fly this season. That's the second highest snowfall tally this early on record. At the NWS office near Prince's Paisley Park studios in Chanhassen, a whopping 22.9" has fallen so far.
The only year with more snow to date was 1991...the year of the Halloween Mega Storm.
La Nina to blame?
The latest monthly El Nino Southern Oscillation (ENSO) Diagnostic's Discussion is hot off the presses today. (And yes, my name is Paul Huttner and I'm a weather geek)
The headline is that La Nina (cooler than average ocean temperatures) persists in the tropical Pacific. This could be one reason we are off to a snowy pattern in 2010-11. While there is no discernable link to snowier winters in La Nina years in sotuhern Minnesota, there is a statisitacal correlation to more snow in nuch of the northern USA, inclding northern Minnesota.
Here's the verbage from NOAA's CPC.
"Likely La Niña impacts during December 2010-February 2011 include suppressed convection over the central tropical Pacific Ocean, and enhanced convection over Indonesia. Impacts in the United States include an enhanced chance of above-average precipitation in the Pacific Northwest, Northern Rockies (along with a concomitant increase in snowfall), Great Lakes, and Ohio Valley. Below-average precipitation is most likely across the southern states, extending into the Mid-Atlantic region. An increased chance of below-average temperatures is predicted for the northernmost western and central states, and a higher possibility of above-average temperatures is forecast for much of the southern and central U.S. (see 3-month seasonal outlook released on November 18th, 2010)."
So far the winter season winter is going according to the La Nina plan in the Upper Midwest.
Prolific Lake-effect in Wisconsin & Michigan's U.P.
Check out some of the snow totals from this week's prolific lake-effect snow event on the south shore of Lake Superior. Anywhere form 15" to 30+" has fallen with the season's first big arctic outbreak just east of the Apostle Islands.
That loud cheer you heard was my kids jumping up and down at the thought of big snow for the weekend !