NY NJ PA Weather Forecasts

The latest satellite trends clearly show clouds breaking up to the west and clearing skies on the way.  For the rest of the day, expect partly cloudy skies to develop as the last showers and thunderstorms pull away from Long Island this afternoon.

By this evening, the forecast area will be in between disturbances, which will mean dry conditions through the evening hours.  

Another strong disturbance will develop over the eastern Great Lakes on Thursday morning and move through the forecast area on Thursday evening with wide spread showers and thunderstorms.  The thunderstorm complex will develop much the same way as the thunderstorm complex from this morning, and may lead to another episode of heavy rainfall for the forecast area.

The majority of the severe weather today will be focused over the central Plains to the mid Mississippi Valley and over the Tennessee Valley.  A series of disturbances will enhance the cold front in these locations to produce showers and thunderstorms.  An MCS currently over Kansas will also enhance the frontal boundary at the surface over these locations.  The mid and upper level disturbances will enhance vertical speed and directional shear, which will lead to a favorable environment for isolated tornadoes, large hail, wind gusts over 65 mph, and heavy downpours.

Another strong disturbance will move through New England and the northern Mid Atlantic through the day with showers and thunderstorms.  The main threat from these thunderstorms will be the very heavy rain with rainfall amounts over an inch possible in many locations.

An area of heavy rainfall is moving through western Connecticut, the southern Hudson Valley, New York City, and much of western Long Island this morning and will continue to move through the rest of Connecticut and Long Island over the next several hours.

This rainfall is associated with a strong mid level disturbance moving through New England in response to a developing upper low to the north of the region.  Rainfall amounts from this area of showers and thunderstorms have ranged from 0.5″ to 1.5″ based on doppler radar estimates.  

Heavy rain can be expected through out the five boroughs of New York City, the southern Hudson Valley, Connecticut, and Long Island through the morning.  Rainfall amounts will range from 0.5″ to 2″ with locally higher amounts.  Urban flash flooding will be possible from these thunderstorms and significant reduced visibility.  Use caution if driving in these thunderstorms.

The model guidance from 00Z and 06Z has some very interesting signals for the middle of the month and perhaps a few clues for the next few months.

Both model guidance, and most so the GFS, continues to portray a pattern of a ridge in the western United States and a large trough in the East.  Meanwhile, a strong ridge develops over the Caspian Sea to such a strong extent that the GFS literally connects the two ridges and would produce a cross polar flow from Siberia to the Eastern United States.  If this was winter, a lot of people would be screaming arctic cold and so on.  

However, what this potential pattern shows is that I think we can expected much of the rest of August to remain near to below normal in temperatures and near to above normal in precipitation.  While the West will bake under a strong ridge, a series of cold fronts will bring Fall like conditions to much of the East coast, especially by the middle of Augusts.  

I know I’ll get this question, so I’ll answer it now.  What does this mean for the winter?  Well, the fact that this pattern is already showing up does give me a clue that the atmosphere will be for conducive for a west ridge/east trough pattern.  However, I still think we are a little too far off to make a defined winter forecast.  Is this pattern showing up more and more?  Yes.  That certainly helps in defining the pattern overall.  However, we are over 100 days away from even the first significant cold front of the season (30’s and 40’s for highs) and a lot can change between now and then.

The general forecast discussion is updated and ready to be viewed.  A few thoughts about today’s forecast.

1. The low pressure discussed yesterday seems to be forming a little bit more to the east, which should spare much of the forecast area of the effects of this developing low pressure system.

2. The upper trough through the next 7 days will send several disturbances through the area, but not rainfall every day.  

3.  Don’t expect any hot conditions for at least the next 15 days as the hottest 850 MB and surface temperatures remain over the Plains and Rockies.