Weekend Looks Fantastic for Fall

This Weekend's Forecast:

Snow in the CT Hills, Snowstorm for Northern New York

It's not even Halloween. The elections are still to come.

...SNOW?

On Tuesday, expect rain showers on/off through out the day. As a large storm winds up to our SE and East during the day, a cold front will pass through the region. Temperatures will become even chillier than previous days. With that, the result is snow. Yes. Be prepared for some rain/snow showers throughout the evening. These rain/snow showers will continue through Wednesday. Don't get too mad about this early showing of snow, as portions of northern New York state will easily pick up a foot!
Forecast Graphic:
GFS Snow Output Graphic:

Nothing much happening

I havent posted in over a month so i figured i would post a quick update on winter weather and the tropics, we have the tropical storm well out in the Atlantic dying as we speak.. So who cares? Not much going on in the nation with winter weather really, so check back during a major snow event or tropical system.

-zackc

Tropical Storm Nana

TROPICAL STORM NANA ADVISORY NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL142008
500 PM EDT SUN OCT 12 2008

...NEW TROPICAL STORM FORMS IN THE EASTERN ATLANTIC...

AT 500 PM EDT...2100Z...THE CENTER OF TROPICAL STORM NANA WAS LOCATED NEAR LATITUDE 16.4 NORTH...LONGITUDE 37.9 WEST OR ABOUT 925 MILES...1485 KM...WEST OF THE CAPE VERDE ISLANDS.

NANA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 7 MPH...11 KM/HR...AND THIS MOTION IS EXPECTED TO CONTINUE OVER THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER GUSTS. WEAKENING IS EXPECTED DURING THE NEXT DAY OR SO...AND NANA IS FORECAST TO BECOME A TROPICAL DEPRESSION TONIGHT OR MONDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 85 MILES...140 KM FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB...29.68 INCHES.

REPEATING THE 500 PM EDT POSITION...16.4 N...37.9 W. MOVEMENT TOWARD...WEST-NORTHWEST NEAR 7 MPH. MAXIMUM SUSTAINED WINDS...40 MPH. MINIMUM CENTRAL PRESSURE...1005 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT 1100 PM EDT.

A cold and stormy November possible

Taking a look at the September 500mb height anomalies, three distinct regions are evident.


I created a time series for the three areas, and sorted the years to find a best match for each one. Using the each time series, I also made a custom series (Area B + Area C - Area A). I took the top 20 (minus 2008 which was first as to be expected) for possible analogs and sorted through them, eliminating El Nino and +AAM years as well as years where the custom data was skewed due to a strong anomaly in only one of the areas but not the rest. The resulting years (in chronological order) were 1949, 1956, 1960, 1961, 1963, 1967, 1972, 1974, 1989, 1995, 1999, 2007.


As you can see, the average of the list of analogs returns a fairly close match to the September 2008 pattern.

Because features in the atmosphere are interconnected to some degree, using the analogs presented, we can get a general idea for the future. Roll forward analogs generally work best in the 25+ day range. This is because before then there is a transitional period during which the signals from each analog are widely spread and average to a weak, blurry signal.


In this case, the October analog average does not have high magnitude anomalies, however November features an node in the analogs. There is a strong signal at this time for +PNA ridging with a trough over the eastern US. In fact 11 of the 12 analogs show below normal heights in the east with the only exception being 1999 during which the mean ridge axis was further east.





The MJO should be into octant 5 of phase space by November 15 to 18, during which time a negative NAO develops. At this point in time, the possibility of a measurable snowfall between the 18th and the 25th is looking good.

Early snow possible!!!!