Wednesday, September 12, 2012

Long Range Cold Weather Is Forecasted By ECMWF

The new 12z ECMWF is forecasting two separate cold outbreaks to strike the Northern US over the next 10 days, with the first occurring September 18, and the second hitting on the 22nd.

As shown above, the freezing line that points out below 32-degree temperatures will be south of northern Minnesota and North Dakota, indicating a sharp chill is on the menu for those regions. Additionally, on the second cold outbreak, the cold air should spread farther south and out in all directions over the north central US.

Because this is long range, my confidence in this scenario is reduced. However, the Arctic Oscillation is expected to plummet into negative territory in the next week or two, a signal that cold air can move south from Canada.