A Trip Down Memory Lane: December 26-27, 2010

Got that summertime sadness?

There is not much, weather wise, to talk about for at least the next two weeks. So lets take a look back at one of the most memorable blizzards to strike the NYC Metro area.

December 27, 2010.

Here was the final snow map for the Boxing Day Blizzard:



This impressive storm dropped 10+ inches of snowfall from North Carolina all the way up into Maine. As you get into NJ, there are widespread 1-2 feet snow amounts and, locally, 30+ inches of snow in northeast NJ and parts of southern NY state.

Here is a close up of the northeast:



What was the most essential factor that put this storm together? The -NAO.



An NAO in a negative state brings positive heights into Greenland which allows the jet stream to dip and create a trough along the eastern U.S. This creates an arctic flow of air to filter into the eastern U.S. Now, compare the graphic above created by TWC with the 500mb map the day of 12/27/10...



You see that huge trough in the eastern U.S. with low heights extending all the way down into Florida? That is a very amplified pattern of a +PNA, -NAO, and -AO. This looks very much like the TWC graphic. The -NAO allows two bundles of energy to come together which ultimately develops a powerful Nor'easter, in this case known as the "Boxing Day Blizzard" or in my own terminology, a "Godzilla."

Here are a series of my favorite images or gifs of this historical snowstorm:


























And here are some gifs...

http://cimss.ssec.wisc.edu/goes/blog/wp-content/uploads/2010/12/101226-27_g13_wv_anim.gif

http://www.erh.noaa.gov/okx/SOO/case_studies/12262010/sfcir.gif

http://synoptic.envsci.rutgers.edu/riggi/101226_27_kdix.gif

http://www.erh.noaa.gov/okx/SOO/case_studies/12262010/500mb.gif

Have a nice night,

-Frank

Exactly How "Cool" Will It Get?

By now, we should all be aware of the pattern change that has taken place last week which has ridden the insanely hot temperatures and unbearable humidity. I blogged about it HERE on July 15th...

The biggest reason for this pattern change is due to the abnormally strong PV, or Polar Vortex, this time of year.

The positive heights in the north-central Atlantic, northern Canada, and Greenland...have created an unusual blocking pattern for the commencement of August. Temperature departures relative to average will be between -1 and -4 over the next 10 days or so in the northeastern U.S. and mainly the northern half of the Mid-Atlantic. 

A zoomed in view into the eastern U.S. shows the negative temp. departures from normal nicely. 

In terms of high temperatures, we will be talking mainly 70's (it actually never got out of the 60's today around the Tri-State area due to clouds and rain). Low temps will get into the 50's. Northwestern sections of the of I-95 could see cooler readings, but for the most part, 70's which is still impressive for what are supposed to be the "dog days of summer." 

One thing to also keep in mind is with the battle of positive and negative height anomalies fighting around the mid-section of the country and eventually into the northeast, it could spark the threat for storms to develop. Think of it as a "friction" between the two. It could be enhanced along a front which would develop ahead of the PV that will be situated in southern Canada as it moves on east. 

All in all, 1st half of August should be expected to be cooler than normal with periods of rain at times. The tropics should continue to remain quiet until the 15th. Afterwards, it is beginning to look like fair game for this season to really start picking up as dry air begins to dissipate in the Atlantic. Stay tuned! 

Enjoy your weekend, 

-Frank Paparatto