Quiet For Now

For the last week the Northstate has been bombarded by long lived troughing on the west coast which tapped into deep tropical moisture.

(last week)

A strong blocking high in the North Central Pacific pushed cold air down from the Arctic region allow for a very strong upper level low to sit and spin just off the coast of California,Oregon and Washington.

(next week)

The next 5-7 days the blocking high will shift closer and closer to the West Coast. This will set up a strong northwest jet ending any chance for rain, mainly just a gusty north wind event on Sunday.

Let's Take a Look at the Teleconnections.

PNA

For the last month the PNA oscillation as been quite negative.  Which typically signals a blocking high in the North Central Pacific and in the fall/winter a better chance for a stormy pattern on the West Coast.  You'll notice now the shift is from negative to neutral ending our month long block.

AO

The AO is the measurement of how wavy an active the Jet Stream is in the Fall and Winter.  The more negative the better chance for strong troughs to dive down into the lower 48.  So we are forecasting a strong negative AO.  Yet it looks like the Rockies and east will see most of this cold air.

NAO

NAO is a good signal for blocking in the North 

Atlantic.  Typically in the Fall/Winter a strong negative NAO means a blocking high over Greenland which then allows for troughing over the East.

Next Week

So there you go, a fairly cold air outbreak next week for a good chunk of the US minus the West Coast.  Strong oscillations except for the weakening of PNA.

Until some of the blocks shift and we see the MJO pick back up, the Northstate looks quiet the next 1-2 weeks.