Sunday, August 12, 2012

Official 2012-2013 Winter Forecast Release Date

Mark your calendars!

The release date of The Weather Centre's Official 2012-2013 Winter Forecast will be Saturday, September 8, at 12:00 PM central time.

I will begin work on this forecast tomorrow. It may surpass the last forecast update in terms of amount of work put into it, but this will be an exciting forecast!

Andrew

Transformation into Positive PDO May Be Occurring

http://www.bom.gov.au/products/IDYOC059.shtml
A difference in temperature anomalies between June and July shows a cooling pattern now occurring in portions of the Northern Pacific, as well as a warming trend being observed on the Canadian and Alaskan coast, typical to what would be seen in a positive PDO.

http://jisao.washington.edu/pdo/
A warm phase, or positive PDO, is characterized by a cool North Pacific, as well as a warm coast of western Canada and southern Alaska. Also of interest is the warm anomalies in the Equatorial region and ENSO monitoring area. That said, it can be said that a positive PDO has a correlation with El Nino's. That does not mean that every El Nino has a positive PDO, but typically, they can occur together.
On the other hand, a cool phase of the PDO contains warm temperature anomalies spread across the North Pacific, as well as a cool Gulf of Alaska coast. Additionally, cool temperature anomalies are found in the ENSO monitoring area, showing a correlation between a negative PDO and La Nina.

A positive PDO typically brings about a warm and dry spell in the Northwest, which indicates a ridge of high pressure is in the area. Additionally, cool and wet conditions are found in the Southeast, showing that many disturbances move through the area during the October - March period.
You can find more effects in other areas in response to the PDO by clicking here.

Andrew

Great Lakes 4-8 Degrees Above Normal; Winter Lake-Effect Snows May Be Intense

Latest analysis of sea surface temperature anomalies in the Great Lakes show that the Lakes are 4 to 8 degrees (c) above normal, with some areas even warmer than that.

This winter will be composed of an El Nino, which should bring some variant temperatures across the Eastern US. If an arctic outbreak can come out of this winter, and keep hold for several days, the lake effect snow machine could go hard. Considering many areas get above 100 inches thanks to lake effect snow, I can see those same areas getting as much as another 7 feet or more, should a few arctic outbreaks pump those lake effect snows into action.

These snows could very well be helped if we see a repeat of the strong storm system we saw a few days ago in the Great Lakes region that produced gusty winds and dropped temperatures to unseasonably cool levels. If that happens again, the lake effect snows will only pile on more and more.

Andrew