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Tuesday, December 11, 2007

A BIG STORM FOR THIS WEEKEND !!! Rain & Snow with Plenty of WIND !

A Weekend Nor'Easter is looking very favorable at this time !

Discussion & Some Thoughts:

A Classic Nor'Easter is setting up for this upcoming weekend. The pattern is prime and the setup is for a "Big Coastal Storm", for the Mid Atlantic and Northeast for Saturday Night into Monday morning. This storm will likely make some big headlines. I'm most concerned with the wind this storm will produce, Sunday into Monday. Those that do get the heavy wet snow, will have serious problems, with Trees coming down along with power lines and outages.

Our storm will originate and slowly develop in the Lower Mississippi Valley, and Gulf States on Friday. Strong High Pressure and a fresh supply of Cold air will also be pressing into the Northern Plains, The G/L and Northeast, during this time. This High is enlongated in an East west orientation, that will allow blocking, and prevent the storm from moving Northeast into the Lakes. This High and Upper Level Pattern, will help keep the flow flattened and zonal to our south. This will cause our storm to move Eastward into the SE States on Friday Night and Saturday.

A large area of Precip will develop, well ahead of this storm, due to overruning, of warm moist air to the south, and cold air being pumped down (Some CAD) from our High to the north. I'm expecting all areas to begin and end as snow, here in the Delaware Valley. At this time, I'm thinking a change over to a mix of Sleet and Rain, is quite possible, from the I-95 Cor. of DCA to NYC and East to the Coastal Plain.

The latest 12Z Operational Runs of the GFS, EURO, and GGEM are all showing a huge hit for the entire M/A and Northeast with this storm. The trends continue to favor a Coastal Low rapidly strengthening just off the M/A Coast near VA/Delmarva Coast by Sunday Morning. The storm then moves NNE and just off the NJ Coast by later Sunday Afternoon, and to near Eastern L.I. by Sunday Evening. This storm really begins to Explode and 500mb Height's Crash over Eastern PA, and NJ, during Sunday Afternoon and Evening. This is when I expect the winds to really pick up and any rain or mixed precip to change back to snow, over parts of NJ, DE and SE PA.

Who get's the Snow, Mix, and Rain ??? This is the Big Question.

The biggest uncertainty now is the precip type, as the exact track of this storm is not etched in stone, and is nearly 5 days away. I will say, the latest trends are looking much better for this storm to stay near or just off the Coast, this opposed to an inland App's track, from previous runs yesterday.

At this time I'd say that RDG, PA and ABE, PA have the best shot at Heavy snowfall and a primary snow event. If this is an all snow event 6" to 12" amounts would be common, If the storm pans out and performs as I'm expecting.

PHL and the Surrounding N & W Suburbs, are looking at a 60% to 75% snow event. It appears a changeover will occur and mixed precip of rain and Sleet, will hold down snow accumulations in the PHL/SJ area's. This would likely occur later Saturday Night into Sunday morning, before changing back to snow during the afternoon.

I still think the front runner of the storm could produce at least "Several Inches" of snow, before any mixing occurs, along with a change back to "Some Accumulating Snow" during Sunday Afternoon and into Sunday Evening.

For Southern NJ and Delaware:
Well guys, can you hear that violin playing in the background ? I'm afraid to say but this could be a big heartbreaker for SJ and DE snow lovers, such as myself. I do think we get some snow on the front end, and backside of this system with "Some Accumulation", but a cold rain or Mixed Precip. will likely rule for about 50% to 60% of this storm.

The downfalls are that the Ocean Water Temps are in the low 40's, and the storm track is somewhat unfavorable, and too close to the Coast. The strength of this system approaching from the South and SW, is also a very critical player. The weaker the system is to our south, then the better off we are here. It would be most favorable for the storm to track about 150 miles further South and East, and for most of the strengening,to take play further north, and Off the DE/NJ Coast. Some of the model and ensemble members, still say there's hope for this to happen. So all South Jersey and Delawarians, hang in there. There's still some hope for a Nice snowstorm, as the Exact track of this storm, is still up in the air.

I think Thursday Night or Friday, is when I'll take my first shot at calling this Storm. Until then Enjoy this Great December 07 Pattern !!!

Some Key Impacts I'm expecting with this Big Weekend Storm !
For the Delaware Valley, The M/A, and The Northeast Regions.

1. Very High Winds for Sunday into Monday of 35 to 45 mph. Gusts to near 60 Mph. can be expected.

2. Coastal Beach erosion from NJ into much of New England.

3. Widespread Snowfall amounts of 1 foot or more from The Central Apps into Interior New England. The exception being the I-95 Cor. and Coastal Plain where amounts will be less, but BOS, MA is game for a nice hit.

4. Downed trees and Power Lines will be common, especially in areas that receive Heavy Wet Snow, most likely from PA/NJ and into New England, where the highest winds are expected.

Take Care,
Ruggie

2 comments:

Anonymous said...

Ruggie I am going backpacking this sat sun on the A.T in Md. The mountain I will be on is south mountain about 1500-1700 ft. How much snow and when do you think it will start. I am leaving Sat morning around 8 am Thanks
john

Anonymous said...

you email me at hiker1252@yahoo.com
john