Thursday, October 27, 2011

Snowmageddon Saturday In the Making?!?

Today's 18z NAM has just come in and it is truly spectacular.
We are poring over the NAM and have gathered a few eye-popping images from the run.
The following images are from Hour 54.
First, we have to watch temperatures. With any coastal storm comes the risk of too warm temperatures that may create a rain situation instead of snow. At this time, it appears temperatures should be cold enough for the situation to be a snowy one. Below is the precipitation map from the same hour.
Take a look at that! This low is projected to be very intense, and a huge bulk of high precipitation arriving in the coastal area of the Northeast- where temperatures may be cold enough for snow. Be sure to check back in as the situation unfolds and we get more images of the NAM (snowfall, etc.)

Energy for Upcoming Northeast Snow Currently in Ohio

The energy for the upcoming snowfall in the Northeast is currently in the Indiana/Ohio region and strengthening. Areas of yellow, red and darker colors are the lower pressures on this 500 mb chart. Areas with relatively low amounts of yellow are typically experiencing nicer weather.
This energy currently in the Ohio region will continue to move eastward, come into contact with the Atlantic Ocean, and produce snowfall. Below are current estimates from the NAM model of snowfall within 3 hour time frames.

9 hour forecast snow accumulation

12 hour forecast snow accumulation
Total snowfall should remain in the 2-6 inch range.

Final Winter Forecast comes out November 5th!

The FINAL 2011-2012 Winter Forecast will be Released November 5th at 12:00 PM CDT for the national forecast.

Regional times are as follows:

Nationwide Winter Forecast Release: 12:00 PM CDT
Southwest Winter Forecast Release: 12:10 PM CDT
Southeast Winter Forecast Release: 12:20 PM CDT
Northeast Winter Forecast Release: 12:30 PM CDT
Midwest Winter Forecast Release: 12:40 PM CDT
Northwest Winter Forecast Release: 12:50 PM CDT
South Central Plains Winter Forecast Release: 1:00 PM CDT

0z ECMWF Back to Bombing Out on Northeast for Weekend Storm

For all you snow lovers in the Northeast, I am happy to report that this morning's ECMWF model run has trended back to its original solution from a couple days back. That is, the ECMWF now bombs out the storm while on the coast. ('Bombing out' is a term used for when a low pressure system rapidly drops central pressure and gains strength. Typical occurrence with coastal storms.)
The HPC, which provides some of its own winter graphics, shows the highest reasonable (at least 40%) amount of snowfall possible at 1 inch for much of the Northeast and 4 inches for northern New Jersey.
This probably will not be a huge storm, but there may be a coating of snow on the grass or pavement.