On paper from 5000 to 1000 feet this is a snow storm but at the surface we could have a battle of snow vs. rain. It does look like a burst of precip from 8pm to 1am in the Baltimore-Washington Area....9pm to 3am in the Philly Area... Midnight to 7am in the NYC and southern New England area. The further north you go the better chance of snow.
I still think it will be just cold enough to get a period of moderate wet snow late Wednesday night so lets look at the raw numbers top to bottom first and than put together an early forecast.
THE LEHIGH VALLEY (LEHIGH-NORTHAMPTON-UPPER BUCKS)
Allentown sits further north of the LOW and will more than likely be wet snow at this point. It may start as rain...rain/snow mix but should change over to wet snow for 6-8 hours and it could get moderate at times according to the GFS and NAM.
NAM .62" liquid....... surface temps 30-28 degrees......Thickness 534-533
850mb/5000 ft temps 22 degrees. All levels point to all snow 5-7"
GFS .45" liquid........ surface temps 32-28 degrees ...Thickness 538-534
850mb/5000 ft temps 26 degrees. All levels point to all snow 4-6"
GFS NEW .38" liquid...... surface temps 32-30 degrees ...thickness 537-535
850mb/5000 ft temps 26 degrees. Wet snow for now with a light rain start.
MY OUTLOOK RIGHT NOW: Periods of snow Wednesday night with several inches possible right now. The run today is BIG!
PHILADELPHIA & SOUTH TO WILMINGTON DE EAST TO CHERRY HILL
Philadelphia once again sits on the I-95 dividing line and where the temps sits from the surface to 1000 feet will decide how this plays out. That 1000 feet is about as high as the tallest buiding in Philly...the comcast tower.
I buy into some rain and snow in the early evening but on paper it sure wants to change over to wet snow late Wednesday night.
GFS .92" liquid.... surface temps 35-29 falling thickness 541-535
850mb/5000 ft temps 29-25. It's rain to snow but a wet snow for sure.
GFS (NEW) .44" liquid surface temps 34-32 falling thickness 540-537
850mb/5000 ft temps 29-27. A bit colder in the wet snow zone.
NAM .78" liquid... surface temps 32-30 thickness 536-534
850mb/5000 ft temps 25-23. light rain to wet snow at this point.
MY OUTLOOK RIGHT NOW.....Well you can't over look that the temps at 5000 ft easily support snow and even down to 1000 feet it will snow. So far it's a quick storm with moderate to heavy wet snow.
I just took a look at the GFS for the weekend....it's cold and snowy for many from DC to Boston as another nor'easter pops off the coast. It's a developing situation right now so we'll see how the Euro comes in. The pattern is so so ripe for this nor'easter pattern the next few weeks.
Hey Rob, I recently moved from Harleysville PA to Pennsburg PA. I am at the crosshairs of four counties; Montgomery, Bucks, Lehigh, and Berks. I am in the most northern tip of Montgomery County. When you forecast for areas, should i pay attention to the lehigh/allentown/quakertown totals? Thank you.
Rob...when you say Upper Bucks....does that include Doylestown? Doylestown is always in the in-between forecast areas of Philly/Lower Bucks and Upper Bucks/Lehigh Valley. Technically, Doylestown is in Central Bucks, but only 8 miles or so southeast of Quakertown.