Snow on Wednesday

The National Weather Service forecast for this storm is completely at odds with the output of the GFS computer models.  The NWS is forecasting a low that tracks close enough to the coast to bring heavy snow inland and a mix/rain along the coast (starting and ending as snow).  The GFS has the storm track far enough offshore that all precip would fall as snow. In fact, the tracks are far enough off shore that NYC would only see a light accumulation. The forecast track could (and will) change between now and Tuesday night. See the "spaghetti chart" for a graphic of each of the "ensemble members" underlying the forecast models. This gives some insight into the large cone of uncertainty around the track.  Tomorrow night we should be close enough to the event to get a more accurate forecast.

NWS forecast for 11021:
Tuesday: A chance of snow, possibly mixing with sleet after 2pm, then gradually ending. Cloudy, with a high near 36. West wind between 7 and 9 mph. Chance of precipitation is 40%.

Tuesday Night: A chance of snow, mainly after 3am. Mostly cloudy, with a low around 28. Southwest wind around 6 mph becoming calm. Chance of precipitation is 40%.

Wednesday: Snow likely before noon, then rain and snow likely between noon and 3pm, then rain likely after 3pm. Cloudy, with a high near 36. Chance of precipitation is 70%. New precipitation amounts between a half and three quarters of an inch possible.

Wednesday Night: Rain and snow likely, becoming all snow after 9pm. Cloudy, with a low around 26. Chance of precipitation is 70%.


GFS 18Z:

Ensemble Means: