On this last day of 2013 we reached a high of 38 at Philly Int'l, which is three off of the average high; we did have a mixture of sunshine and clouds with even some snow showers pushing through in the late afternoon. Officially it was recorded as a trace of snow AND rain(you melt down the snow to get the water equivalent....so it wasn't much!) so the total precipitation for the year is 55.88"(14.35" above average)! It's not a record of course as the wettest year on record is 64.33" set back in 2011.
New Year's Day will feature high pressure on top of the area and a light westerly wind, BUT highs will just be in the middle 30s; high pressure pushes offshore(which means there's no blocking) as a cold front moves across the Great Lakes AND a low moves up the Eastern Seaboard. Remember how I just said there's no blocking in place....
This leads to two "rounds" of precipitation as these storms will not phase (come together) in time around here; Thursday will start off as a snow-to-rain scenario across most of the region EXCEPT for higher elevations where the temperature will stay below freezing as a coastal low pushes to the northeast. The second "round" will be from the front itself Thursday night into Friday morning as cold air pushing in will allow for light snow to fall with minor accumulations(1-2"). I am remembered of the similar scenario of February 8th 2013 where two systems didn't phase in time with the coastal low moved quickly to the northeast while the front was only across Ohio! Granted it did eventually phase at night and provided Southern New England with one to two FEET of snow!
Behind these systems will be very cold air as temperatures during the day will just be in the 20s on Friday, but the issue will be Friday night as the heart of the cold air will be on top of us. Lows will get down in the lower and middle single digits(and that's not even factoring a wind chill!); now how quickly we get down to near record lows will be something to watch as records go from 12:00am-11:59pm. So...
Record low for
Friday, 1/3: -3 set in 1879
Saturday 1/4: 2 set in 1918
That's all for now and you can check out the 7-day forecast any time at www.scottderekwx.com/forecast.html.