HURRICANE FLORENCE COMMENTARY

The flooding and devastation brought by Hurricane Florence continues in the Carolinas.

I wanted to just weigh-in on the forecasting aspect of the storm.  I haven’t heard very much credit given to the real meteorologists, mathematicians, and scientists that developed such remarkable computer models of the earth’s atmosphere.

The computer models did incredibly well with the precipitation forecast and early/late track of this storm and its remnants.   Possibly the best I’ve seen in recent years.

The new GFS-FV3 model, still in trial mode (to replace the current GFS and become operational in January 2019), also did very well.

While the intensity forecasts are generally unreliable, and were off  with this storm, (it luckily hit the coast as a category 1 instead of the previously forecast category 3-4), the rest of the forecast was very impressive.

Thank you to the National Weather Service and their scientists!

 

WEEKEND WEATHER FORECAST

Hurricane Florence continues on its forecast track in the Carolinas.

Philadelphia will be far enough away from the general circulation of the storm to escape most of the effects over the weekend. It will be breezy on Saturday with winds from the east.  High surf and windy conditions for the Jersey shore.

Partly to mostly sunny skies for Saturday and especially Sunday according to the National Blend of Models (NBM) while the GFS has a bit more cloudiness of Saturday with a chance of light showers late in the afternoon in Delaware.  Highs near 80.

An easterly flow will keep humidity in place with dewpoints in the mid to upper 60s.

GFS Model
GFS Model forecast for Saturday afternoon

 

On Sunday, mostly sunny, occasional clouds,  is forecast.  Dewpoints drop a bit in the afternoon.  High 81.

Heavy rain (1-2 inches) is predicted by the ECMWF (European) and the GFS for Monday night through Tuesday in our area as the moisture remnants of Florence move up into our area.

 

HURRICANE FLORENCE UPDATE- THURS

The latest models continue with hurricane Florence hitting north Carolina, somewhat further south than predicted earlier in the week.  The path southward and then into the US continues to be forecast.

Another change is a decrease in anticipated intensity.  While intensity forecasts are even less reliable than hurricane track forecasts, the latest show Florence to approach as a category 2-3 hurricane and reduce quickly to a category 2.  This is less severe than forecast earlier in the week.

Current tracks (various models) as of Thursday morning.

predicted tracks graphic
Various model predicted tracks as of 8AM Thursday.

The anticipated lingering of the storm along the coast for 24 hours will still result in major wind damage and severe flooding  despite the decrease in intensity level.

The forecast for the Philadelphia area still calling for dry conditions over the weekend.  The cloud shield from the storm may result in overcast conditions.  The statistical models suggest that the remnants of the hurricane will result in heavy rains sometime in the  late Monday  to early Wednesday time frame in our area.

 

WEEKEND WEATHER OUTLOOK- HURRICANE FLORENCE

There’s increasing agreement among the hurricane/tropical models that Florence will approach the North Carolina coast and linger, perhaps for 36 hours before either turning slightly southward or inland.  Prolonged high winds and heavy rain is in store for NC.  A bad situation.

GFS forecast
GFS Forecast for Sat 2 PM

For our neck of the woods, the various models have windy conditions for Cape May to Atlantic City with winds 30-40 mph with some higher gusts.  A mix of some sun and clouds.  The statistical models show the possibility of intermittent showers too.

For Philadelphia, north and west, mostly sunny to partly cloudy conditions and no showers for the weekend, based on the GFS (although the statistical models maintain a low chance of showers.). This is consistent with the subsidence that occurs a certain radius from a hurricane.   It’s not clear how far away the cloud circulation from the hurricane may extend.  Overall, Philadelphia may not experience much of anything until Monday or Tuesday with the remnants of what will be a tropical storm then passing over us.

As with any hurricane, the anticipated track is known to change considerably, so forecast changes are likely.  But based on current models, this is what to expect.

Storm Forecasts & Other Things "up in the air".