The latest NAM data is in and it shows the precipitation taping off and ending between 12 and 2 PM in PHL and its immediate suburbs, with just lingering snow showers possible from wrap-around moisture. Winds will pick up.
Surface temperatures are predicted to drop by 2 PM, as well as temperatures in the upper atmosphere.
A changeover to a bit of snow or snow/sleet mix is possible before ending. BUT the thermal profiles still favor a precipitation mix of sleet/rain/snow and upper atmosphere temperatures remain a bit too warm for much snow formation before the precip exits.
Final snowfall/sleet totals won’t be much different than what you see out your window right now. What you see is what you’ll get.
The changeover to sleet, freezing rain and rain has occurred in PHL and the immediate surrounding suburbs and this precipitation type will continue fairly heavy until about 1-2 PM today. What you see is what you’ll get….If you haven’t received heavy snow, you’re not going to.
Winds will pick up with temperatures at or below freezing early, but rising during the morning. Slippery conditions still exist, but roadways may be less impacted than usual with solar insolation through clouds reducing icing on dark asphalt as we approach noontime. A brief changeover to snow at the end of the storm won’t add much accumulation.
When the TV people try to explain what happened to their 10-12 inch forecasts from last night, don’t believe them. The “track of the storm” didn’t change. They simply didn’t interpret the data properly.
The latest GFS data has come in. The GFS has raised the QPF to over 2.50 inches water. It’s a bit colder than the NAM at the surface, but like the NAM, thickness levels rise to be too warm to support snow by daybreak. Slightly more snow possible before a changeover to sleet/rain.
Difficult to nail down the snow totals, but expect it to be in the 4-5 inch range, maybe 6, before a changeover to sleet/rain before daybreak, significantly reducing further snow totals in the immediate PHL area and the immediate surrounding suburbs.
Areas near Reading, Allentown and Lancaster will have the heavy snow that’s been predicted.
A change back to snow will occur before ending about 2 pm, but the heaviest precipitation will have passed us by.
