Saturday, January 19, 2013

Forecast for Sunday, January 20, 2013

A cold front will move through the region on Sunday and this will be followed by a reinforcing arctic front on Monday Evening and Monday Night. A few flurries may accompany the first front on Sunday with increasing wind following the frontal passage. Gusts of 30 to 40 MPH will be widespread across our region. The second cold front will have a bit more moisture to go along with it and a period of light rain or light snow may accompany the frontal passage, especially in the northern portions of our region on Monday Afternoon into Monday Night. It is possible that some scattered coatings of snow may occur in spots where this falls as mostly snow.

Then it is just downright cold and brisk Tuesday, Wednesday, and Thursday. It will be likely be a partly to mostly sunny period with occasional snow flurries or snow showers, especially in the Poconos. High temperatures will be in the mid to upper twenties with colder wind chill values. Low temperatures will be in the single digits in the Poconos to teens elsewhere. Philadelphia’s coldest high temperature in the past two years was 24 degrees and the coldest low temperature was 8 degrees. At this point, we appear to stay above these values during this cold shot.

Friday into Saturday may be the best shot of substantial winter precipitation we have seen so far this winter. But this event is far from certain and it is still several days away which is certainly plenty of time for drastic changes on the model runs. The models have had a hard time this winter so far and I again point out that the models seem to take days that appear colder far out and warm them up as they approach closer in time. The GFS has two low pressure areas depicted with one arriving in our area on Friday and then another, colder system impacting us on Saturday. The European model has one low pressure system which would deliver the main course on Friday and the EURO is cold enough for mostly snow during Friday. For now, this period of time in the seven day forecast features very low confidence.