Thursday, November 8, 2012

High Impact Snowfall Event for North Plains

I am forecasting a High Impact event for the Northern Plains in the next 5 days, as a major winter weather event hits the region.

What is a High Impact event?

•Heavy precipitation
•Property and Life threatened
•Major travel disruptions

I am anticipating over a foot of snow hitting Montana into the northern part of North Dakota. This could get pretty extreme, especially for rural areas that may see their roads covered, possibly for a long period of time.

Farther to the south, amounts from a half foot to 12'' are likely, as lesser effects of this High Impact event are felt, yet still remain disruptive to travel.

Keep up to date on the latest weather conditions. Make sure you have proper provisions, possibly to use for an extended period of time if your roads are unplowed for an extended period of time.


East Asia Confirming Thanksgiving Storm Worries

Latest model forecasts are confirming my suspicions that Thanksgiving could get pretty messy for the Plains, Midwest, Ohio Valley and Great Lakes. Let's take a look.

This is the 500mb height anomaly forecast from the 18z GFS Ensembles. As you can see, the US is relatively uninteresting at this time period of November the 13th. However, take a look over at East Asia in the upper left hand corner of the image above. A very strong storm system is being forecasted to be digging in to East Asia at this time. The reason why this is so significant is that there is a correlation between weather in East Asia and weather in the East US, approximately 6-12 days later. Keep that in mind as we look at the next image.

This is the 500mb forecast for November 24 at the very end of the GFS' forecast period. This is a good 11 days following the deep East Asian trough. In this forecast, a very strong storm system is being predicted to hit the Northeast and southern Canada, about the same region where the East Asian correlation comes into play. Do you see what's going on here?

If you take another look at yesterday's Thanksgiving post (click here), you'll see how the MJO is moving in to a favorable position for cold and wet weather across the East US in the Thanksgiving Day time period. I also mentioned how the LRC was indicating that a strong storm system would hit the Plains, Midwest and Great Lakes in this time frame.

I guess you could say it's all coming together.

With a possible 1-2 day lag on the above forecast, I am putting out the call that Thanksgiving will be stormy in the Plains, Midwest, Great Lakes regions, possibly extending in to the Northeast as East Asia confirms my fears of such a messy situation playing out in these regions. More updates will follow as I get more information on this system.