Philly Memorial Day Weekend Weather Outlook

Warm, spring-like weather has been conspicuously absent for much of May.   However,  a late spring and more summer-like pattern is evolving in the Atlantic, where a Bermuda high pattern is expected to establish itself over the next few days into the weekend.

Warmer temperatures and higher humidity is expected for Memorial Day Weekend.  It is  unknown whether the Bermuda high will be strong enough to fend off showers and thunderstorms that are depicted to develop to our west, south and north.

Right now, the GFS model is keeping us dry through the weekend, from Saturday through Monday.   But the model trend has been for a weakening of the high pressure dome which may allow showers to sneak in if the trend continues.

So it looks to be a nice weekend here in Philly and at the NJ shore, but it wouldn’t take much for that forecast to go bust.

Sunday Weather Update

Yesterday’s rain did occur mostly in the (late) afternoon, but the models didn’t exactly hit a home run with the forecast.  (The precip was further north and west for most of the day than previously expected.)

Such is the case with upper level closed low forecasts– the exact placement of the precipitation maxima are difficult to forecast.

Today’s forecast accuracy will also be affected by the same situation.   The GFS initialized LAMP forecast has a continued chance of showers here for much of the day.   The NAM initialized HRRR forecast has the upper low pivoting the moisture away from us, with most of the rain in MD and DE  during the afternoon.

The HRRR did well yesterday, so we’ll see if the rain stays mostly to our south in the afternoon.

Weather… and Other Things 'Up in the Air'