Christmas Mega Storm 2009: Here it comes

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Twin Cities NWS painting heavy snowfall and ice potential through Saturday.

This could be the biggest snowstorm in at least 10 years for many parts of Minnesota.

The major winter storm is moving into Minnesota late today and tonight. If you have travel plans within Minnesota, it will be best to arrive at your destination by 9pm tonight.

Here are the latest forecast trends and snowfall amounts with the storm.

-The big picture is remarkably consistent, as it has been all week. Expect snow in most of Minnesota, mixing with sleet and ice in the southeast quarter of the state, from tonight into Saturday.

-It appears precip will remain all snow during the entire storm north and west of the Twin Cities.

-Prolonged ice storm conditions may occur Thursday for southeast Minnesota, including Rochester and Winona.

-The Twin Cities should see snow beginning this evening. The snow may change to sleet and ice Christmas Eve, before changing back to all snow Christmas Day.

-The big, slow moving low will stall through Saturday just southeast of Minnesota. This will produce a long duration snow event of 48 to 60 hours for many areas.

-It appears the heaviest snow will fall in a band along 40 miles either side of Highway 23 in Minnesota. This includes Marshall, Redwood Falls, Willmar, St. Cloud, Brainerd, Hinckley, and Duluth. These areas could see 15″ to 20″+ by Sunday, with some totals approaching 30″ possible.

-From Mankato to the Twin Cities, a mix of freezing rain on Christmas Eve could reduce snow amounts slightly. Anywhere from 12″ to 18″+ is likely in the Twin Cities by Sunday. If the precip remains all snow in the metro, there could be over 20″ in some areas, especially in the west and northwest metro. In areas that see several hours of sleet and freezing rain on Christmas Eve, snowfall totals cloud be as little as 7 inches. This is most likely in the east metro.

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Overnight Cobb output suggests a potentially lower snow total for Twin Cities Airport of near 8 inches. This reflects the change to freezing rain on Christmas Eve.

-Look for a possible significant ice storm in southeast Minnesota, along with 6″ to 12″ of heavy wet snow by Sunday.

This storm may set both daily and storm snowfall records for many areas of the state. If we get 16″ in the metro, it will equal the biggest single storm snowfall in over 10 years. We recieved 16″ in March of 1999.

The bottom line is regardless of eventual snowfall totals, travel conditions will be difficult to impossable in much of Minnesota over the next several days. Hopefully you can arrive at your holiday destination and just enjoy the snow. This should be a great holiday for kids of all ages who love playing in and looking at big snow.

Here are some links to keep track of updated weather conditions today.

Travel safe and have a great Holiday!

-Twin Cities NWS storm page

-Twin Cities radar loop

-Sioux Falls NWS

-La Crosse NWS-Des Moines NWS

-Duluth NWS

-Grand Forks NWS

-Latest Midwest surface map

-Cobb snowfall output for Twin Cities MSP airport

-Twin Cities Christmas snowfall records

-Top 11 all-time Twin Cities snowfall records

PH

  • Steve

    Is the Cobb model run which predicts the change to a rain/sleet mixture considered a more or less reliable computer model? If you had to pick a favorite model for this storm which would you consider to be most accurate?

    Thanks for the updates and the science behind them!

  • http://www.twoevils.org/ April King

    The bottom line is regardless of eventual snowfall totals, travel conditions will be difficult to imposable in much of Minnesota over the next several days.

    While I do find a portmanteau of impossible and imposing to be highly amusing, I think you probably just meant “impossible” there. :)

  • Paul Huttner

    Hi Steve:

    Great question!

    The Cobb technique can be run on any model out put such as NAM, GFS etc.

    It’s funny but different models handle different storms in different ways. One might be better with one storm etc.

    I do think it’s looking more likely that we’ll mix in with some sleet/freezing rain tomorrow. The Twin Cities will be right on the razor’s edge for the ice/snow line, bfore going back to all snow Christmas Day.

    This could literally be one of those storms where we have a huge range in total snowfall across the Twin Cites from west to east.

    Maybe 7 or 8″ with ice east, and as much as 15″ to 18″ west. How’s that for a crazy forecast??

    Either way it’s going to be a big mess, no matter how much snow actually falls in the end.

    My buddy Craig Edwards will take over for a while this afternoon and good friend Mark Seeley will chime in tomorrow morning. I’ll be back tomorrow PM.

    Enjoy!

    PH

  • Vince

    Lower snow totals for the airport is good. But is freezing rain any better for airplanes taking off and landing on Christmas Eve?

    P.S. Awesome blog!

  • Tim Arnold

    Can you comment on the model runs for Duluth MN? It looks like the NAM models predict an incredible amount of smow. I assume the NAM models take into account the lake effect snows and the GFS models don’t. Any comment?

  • Jerry

    Given the magnitude and duration of this storm, as well as the number of people whose travel plans will be affected by this storm over the holiday, it would be nice if MPR ramped up the frequency of its check-ins with its meteorologists on the air.

    Thanks for the information and all your hard work – it’s got to be a sacrifice on your part to be spending so much time on this rather than with your family during the holidays.