Bolaris: Weather madness Thanksgiving week
It's weather madness. We could set record highs today as balmy southwest winds will send the thermometer into the 70s, with the record for Philadelphia standing at 71.
Then snow is still possible for Thanksgiving - yes, snow just days after those highs.
First, let's get to the start of the week. Tuesday will be nice with no rain and a decent amount of sunshine. Temps will be seasonably cool in the lower 50s.
After that it looks like our goose is cooked, or should I say turkey. Computer models as of early this morning were showing a storm system that will develop off the Carolina coast and race northward. As it does, the storm will intensify rather rapidly.
But that's all the models agree on now. The two most used computer models, the Global Forecasting Model (GFS) and the European Forecasting Model (EFM) are in different camps.
The GFS calls for the grinding out of a colder and snowier day Wednesday into Wednesday night. It's indicating snow amounts of 6 inches for Philly along the I-95 corridor, as well as the surrounding suburbs, including interior Southern New Jersey and North Delaware.
Camp Euro leans towards a track closer to the coast, with a more intense but a milder push of ocean maritime air getting interjected into the storms. That circulation would keep it more on the wetter side from Philly and all points south and east.
Keep in mind, computer guidance is just that - guidance. It should not be used as the "Bible" in putting out a forecast.
My early forecast outlook is a blend of the models and perhaps of more importance, climatology, based on the time of the year and past atmospheric similar set-ups. Also I look at the overall weather global phase. The NAO (North Atlantic oscillation) is in the positive phase which usually leads to a lesser chance of significant snow as a colder blocking pattern is not present.
Other significant factors that would have me believe less in the way of snow is simply we have no cold air already in place for the start of the storm. An Arctic high pressure feed is missing from northern New England, the Atlantic Ocean is still relatively mild during this time of the year. Lastly, even when we do see a changeover to snow, ground temps will still be above freezing meaning that any snow that falls should melt upon surface contact until we reach freezing.
Here's my forecast:
-Wednesday: In the city, a cold rain arrives by morning. It could mix at times with a little sleet and wet snow flakes. But I'm not anticipating any accumulating snow during daylight hours. High temp - 38.
-Wednesday night: A changeover to snow is likely, and could be a slushy accumulation, especially on grassy surfaces. Low of 32.
-Thanksgiving: Dry and cold, 40 degrees.
For Southern New Jersey & Northern Delaware:
-Wednesday: Cold rain, high of 39.
-Wednesday night: Rain, changing back to snow before ending. Light slushy accumulation with possible low of 32.
-Thanksgiving: Dry and cold, 42.
Northwest suburbs:
-Wednesday: Rain, occasionally mixing with sleet and snow, changing to all snow by later in the day or early evening. High 35.
-Wednesday night: Snow accumulations likely in northern Montgomery and northwest Chester counties. In upper Bucks County, we could reach warning levels. Five inches of snow would justify a winter storm warning. it's too close to call at this time. Low of 29,
-Thanksgiving: Dry and cold, with a high of 38.
This weather surgeon general reminds you that this forecast could be hazardous to your health. Go to weathersavior.com for continuing updates.