Updraft: November 23, 2009 Archive

Thanksgiving Travel: Roll the weather dice

Posted at 8:32 AM on November 23, 2009 by Paul Huttner (2 Comments)

Twin Cities NWS graphical forecast indicates snow Wednesday.

Welcome to my weather nightmare.

First of all, it's Thanksgiving. One of the busiest travel weeks of the year. The magnifying glass is on weather this week.

Secondly, we have a very non-traditional storm system to decipher. Twin low pressure systems are spinning through the Upper Midwest this week. The forecast models, and the forecasters, don't like "non-traditional" weather systems. Give us a nice clean Alberta Clipper or panhandle hook any day.

Here are some of the interesting (and challenging) aspects to this week's evolving weather systems.

-Twin lows developing and deepening right over the Upper Midwest.
-Warm air in place through Tuesday, making for a later changeover to snow.
-Models performance can be questionable in these situations. To quote a recently famous military leader; "We don't know what we don't know."
-There are still significant model differences in timing, precip type and location of precipitation.

NAM forecast model shows "twin lows" rotating into Upper Midwest Wednesday.

So here's the early crack at deciphering the weather code this week for holiday travel. Buyer beware, this forecast may change tomorrow.

Monday & Tuesday: Scattered rain, warm enough for all rain except in far northwest Minnesota, where some icing may occur.

Tuesday Night & Wednesday: Rain changes to snow. The GFS model has been leaning toward a period of 24 hours from late Tuesday night to late Wednesday with periods of snow. The NAM pushes everything east into Wisconsin. The European model would seem to favor a quick 12 hour burst moving off to the east.

The trump card in all of this may be unusually warm ground for late November and temperatures just above freezing for most of the day Wednesday. That could mean mostly wet roads, instead of mostly icy roads.

Thanksgiving Day: Colder with snow east of the Twin Cities. Travel could be slippery between the Twin Cities and Chicago. Highs in the mid-30s with a biting wind. This should be a pretty typical Thanksgiving Day weatherwise. We have a white Thanksgiving about one in every three years in the Twin Cities.

Friday & Saturday: More sun, milder with highs into the 40s. The best days for travel!

Sunday: A chance of snow.

Keep an eye on the forecasts this week. Things may change quickly.

PH

Jet Streaming Returns: We want your weather questions!

Posted at 4:41 PM on November 23, 2009 by Paul Huttner

I've had many questions from you wondering where our weekly weather show
"Jet Streaming" has gone. We have some good news to announce!

MPR will air a special edition of Jet Streaming will air on MPR News (KNOW 91.1FM metro) on
Sunday, December 13th at 6pm. The one hour show will feature an outstanding line-up of guests and topics.

We will talk with experts about the developing El Nino and Minnesota's winter forecast. We will talk about the future of weather broadcasting and where advances in weather technology will take us in the next few years. We will also talk about the science of snowflakes, the latest climate change news, and the observable effects of climate change in Minnesota. There will also be special surprise guests who you know and love.

But you are the most important guest! And we need your help.

We'll be answering a series of listener questions about weather and climate. Anything is fair game. We would love to hear you ask your question on the show and answer it personally in the classic MPR style. We may also read your question on the show if you're the shy type.

To help us out, please submit your question here on Updraft, or send me an email at phuttner@mpr.org. I will contact you and arrange to get your question on the show if it seems like the kind of question Jet Streaming listeners would like to hear. We need your questions by December 2nd.

Thanks again for all the support for Jet Streaming. You'll love to hear what we have planned for December 13th!

PH