Sunday, February 22, 2015

Second Round of Harsh Arctic Air Flowing Southward

The second round of intense cold air in under a week is on the way for millions in the Northern United States.

Tropical Tidbits
Click images to enlarge
The above image shows the latest GFS model forecast for Monday morning. On this chart, we see temperatures in the negative-teens across Wisconsin, Illinois, Minnesota, Iowa, Michigan, Indiana, and Ohio. The most intense cold is projected to hit northern Wisconsin and southwestern Michigan, but that doesn't take away from the cold in the other aforementioned areas.

Tropical Tidbits
The GEM model, with its notorious cold bias, agrees with the GFS model. Here, we see a swath of bone-chilling cold in southern Minnesota and Iowa, where temperatures are forecasted to approach -30 degrees. This is more than likely overdone, but the general trend of very cold temperatures similar to the GFS stands in Wisconsin, Illinois, Michigan, Indiana, Ohio, and even into the Dakotas.

Other model guidance, mainly the NAM model, is favoring a warmer solution than the two depicted above. It comes out to the GFS/GEM models and their ensembles, against the NAM/SREF models/ensembles. The National Weather Service appears to be favoring the NAM model / warmer forecast, even though morning observations in the Dakotas and Minnesota support a more GFS-like evolution. Regardless of what happens, another very cold morning is in store tomorrow.

To summarize:

- Another bout of harsh Arctic air is on the move south.
- Temperatures could drop into the negative-teens in some spots.
- Uncertainty still exists with how cold it will get.



Anonymous said...

Great, will there be any discussion on when the vortex may be breaking down any time soon?

Anonymous said...

This really bits! Any end in all? When? March looking to warm up? I have never gained so much weight in my life as I have this winter! I can't take the cold, this kind of cold we've been having! You know, its times like this that I wish Al Gore was right & we really were in Global warming at least it'd be warm! Where is that crazy guy anyway? I'd really like an explanation of what he thinks now!!
Thank you Andrew for keeping us in the know! Please for the love of God tell us when we can expect warm "Spring"!!
Thank you!

Anonymous said...

Forecasts show a -PNA and a +AO at the end of this week, for how long nobody knows. The MJO is all over the place.

Anonymous said...

Hi Andrew,
With the negative PNA and positive AO, could we be seeing a pattern change? The MJO does start become a little more coherent.