Category Archives: Weather Forecasts

Philly Weekend Weather Forecast

A departing up air trough will allow high pressure to build in from the north this weekend.

The instability and resultant cloudiness w’ve had this week as a result of this upper trough will also diminish, and we’ll see more sunshine with continued pleasant temperatures. (Average high temp for this week is about 78 degrees.)

Sat 5/30: Mostly sunny. Pleasant. High 78.
Sun 6/1: Sunny and pleasantly cool. High 77.

Just a note that the long range models have yet another cool and unsettled period for us in a few weeks.



Philly Summer Climate Outlook 2014

The big question that comes up this time of year is whether we will have a hot or cool summer, which is more a question of climate forecasting than weather forecasting. That said, I always like to give climate forecasting a shot. My winter forecast of colder than normal with above normal ice and snow did pretty well. Here’s my take on the upcoming summer–

Three things stand out this summer- the beginning of an El Niño Pacific cycle, the beginning decline in the solar maximum (whose peak sunspot number been lower than several previous cycles), and the continued tendency of the jet stream to dip down as it has been doing for the past 10 months.

The El Niño usually results in wetter conditions for our area and the low solar maximum combined with the continued jet stream dip tendency suggests cooler than average temperatures.

This doesn’t mean that we won’t get hot periods during the summer; that’s what summer is all about. But the my general feeling is that this summer may be cooler than average with above normal precipitation.

Saturday Weather Update

Saturday 8 PM Forecast Map

Last night’s showers that interrupted the Phillies game were forecast to occur, but the chances were low probability.  Low probability clearly doesn’t mean no probability.  The showers were the result of an upper air cyclonic flow and a cool pool of cold air aloft, resulting in  instability and lift.

Today’s NAM model continues with the possibility of instability showers developing between 2 PM and 7PM. —-  expected to be widely scattered and somewhat more numerous in central NJ.

In fact, the NAM lifted index is forecast to be somewhat more unstable today, so scattered showers are likely, although not every area will see them.