Category Archives: Updates


The experimental US Navy COAMPS-TS did a great job at predicting the movement of Hurricane Dorian. It looks like the Navy is tracking several other tropical storms/disturbances and they haven’t released an update on Dorian since early Monday morning.

(I can only guess that their experimental modeling work needs to share computer resources with modeling of other tropical storms.)

Nonetheless, this is the latest COAMPS-TS track available, which is  similar to previous predictions with this model. The storm is not expected to directly hit the Florida coast.   It’s current predicted track is remarkably similar to that posted this past Friday.The vast majority of the other major models have similar tracks for Dorian, as of Monday afternoon.


Hurricane Dorian continues to confound forecasters as the forecast track and  predicted intensity keeps changing.

Rather simplistically, I’ve hung my hat on one of a multitude of hurricane models, the COAMPS-TS, based on its low 24 hour error margin.

The latest COAMPS-TS just available has moved the track further westward again, closer to the track that it had forecast Thursday evening.

18z COAMPS-TS forecast for Dorian

We’ll have to see if the next runs of the GFS and ECMWF models move in the same direction.

As for our weather in Philadelphia, Sunday is looking better with a mix of periods of clouds and periods of sun, especially from Philadelphia and eastward.  (The same strengthening of high pressure that will be giving us some sun tomorrow is likely the same feature that has moved Dorian’s forecast track to the west again.)

Sunday will be rain-free until evening here.

Clouds are expected to move in later Sunday.  Scattered showers appear likely Sunday night and on Monday.



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There has been a significant change in the likely track of Hurricane Dorian.  The US Navy COAMPS-TS and the European ECMWF were the first to pick up on this changed track.  The GFS has joined the pack with this likely change in track.

Here’s the current COAMPS-TS track and intensity forecast:

00z Navy COAMPS model forecast for Hurricane Dorian

(The COAMPS is known to have a northeasterly bias, so this track may be over-done slightly in northeasterly directional movement. )

The current likely landfall area, based on the latest GFS, is near the border of Georgia and South Carolina.


As for our Philadelphia weather, Saturday continues to look good with mostly sunny skies.   Some cloudiness may sneak in late in the day.

Sunday is still looking mostly cloudy, with some sunny breaks possible.  The models keep us dry in Philadelphia and east into NJ, however the models also show significant areas of vorticity (upper air disturbances) that may wring out showers. (Currently NOT shown by the models.)

Monday is currently looking like a mix of sun and clouds, more humid, still dry during the day. The models again appear to be ignoring the vorticities that often bring some scattered showers.



Last Updated

The weekend weather forecast is looking better and better. Last night’s models have reduced their forecast for the amount of cloudiness both Saturday afternoon and Sunday afternoon.   (Still expect some cloudiness, according to the NAM.)

Any precipitation will be during the night time hours.  Monday is looking sunny as well. Enjoy!