Wednesday night update on 2/5-2/7 Storm

In what has been an incredible winter thus far, it becomes difficult to really say one storm is more than the others. This one is just another in what has been a long line of tremendous snowstorms since December for areas that don't always see the big ones.

Just to put this winter in perspective. Albany, NY has received 21.1" of snow, approaching 20" below normal. Williamsport, PA is at about 15"...or close to approximately 10" under average. Philadelphia is at 27.8", Atlantic City is at 24.6", Baltimore is at 35.6", and Washington is at 27.3" or roughly 15-25" above normal. It's well known that climatologically, snowfall behaves VERY erratically. Normal snowfall is rarely normal. It's 2-3 seasons of mega snows followed by several low total seasons that make average. This year is turning into one of the mega-snow seasons from southern NJ through DC and most of Virginia.

Enough history. Here are details. The image up top is a water vapor satellite image. It shows basically the amount of moisture in the atmosphere. Notice...the bright greens and purples over the southern US and Mexico...that's the influx of moisture that's literally coming right out of the center of the Pacific Ocean. To use a sports analogy: The southern branch of the jet stream is basically on steroids...and has been for awhile. Thus, you're getting loads of moisture. Couple that with levels of blocking in the atmosphere that have been almost unheard of in the last 20 years for how sustained they've been, and you've got cold air pouring into the Northeast and Mid Atlantic. Cold air + moisture = Fun.

So this storm will continue to lift toward the Northeast, wind itself up and scoot out to sea, somewhere south of Jersey. This means a couple things. First, it means, like the December 19th storm, there will be a tremendously significant cutoff to the northern extent of the snow. In other words, yes, you can go from 2-3" to 12" over the course of 10 miles. Second it means it looks chilly, which means most/all of what falls in many areas will be frozen (snow or sleet).

The next issue we have to address is whether or not the models are right. There are four scenarios. Two involve track, two involve speed. Mix and match for the scenarios. Does this storm pass just south off of Ocean City, MD? Does this pass off the Virginia Capes? Does it scoot out to sea at a steady clip? Or does it get blocked in by a tremendously massive storm in the middle of the Atlantic Ocean that basically blocks the storm's escape route...thus slowing it down and pouring back heavy snow. We simply can't answer these questions yet.

Right now, my feeling is that the storm will pass somewhere off of Ocean City, MD. It won't crawl out to sea, but it won't be in a major hurry either. Therefore, this increases the risk...both for areas north of southern NJ and in terms of maximum totals from Southern NJ back through Virginia.

So with this all in mind, here's my first call map based on today's model runs and trends. Areas north of a line from about Barnegat Light, NJ-Chester, PA-York, PA need to keep a VERY close eye on this. Because even a 20 mile shift in the track or a slightly slower track will mean MAJOR differences in what you see (aka, more snow). Feel pretty confident about what I have in South NJ back through DC. Totals in Virginia will also be dependent on the storm track, but there's an enhanced risk of higher totals north and west of Richmond.


Click to enlarge.

I'll be glad to post another update on Thursday.

Oh, and PS...could be doing this all over again Tuesday or Wednesday next week....albeit with a smaller storm...but still snowy.