Sept 10, 2011: First Taste Of Fall Next Weekend

Note: The 5-Day Forecast page was updated only for the immediate NYC area tonight. An update late tomorrow morning will update the forecast for the rest of the area as well, including an updated Tropics forecast.

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Today was another partly cloudy and mainly dry day across the area today, as temperatures reached the upper 70s to lower 80s across the entire area. Other than a few spotty showers across the region, today was dry, and the same is expected for tomorrow except that temperatures will be colder due to an ESE wind. Temperatures will warm up again by early-mid next week, reaching the mid 80s in parts of the immediate NYC area on Tuesday which is above the average for this time of the year, but the warmth will not last much longer as a strong cold front will move through, bringing the first true taste of fall next weekend.


Tomorrow's Outlook:

Sunday will bring mostly cloudy skies across the area, but other than a few spotty showers, most of the area is expected to stay dry. A southeast/ESE wind will bring colder temperatures than those of today, only reaching the lower to mid 70s in NW NJ/Orange county, mid to upper 70s in the immediate NYC area, and the lower to mid 70s in Long Island and southern Connecticut.


Monday - Wednesday: Warming Up Ahead Of Cold Front

The clod cover from Sunday should decrease on Monday to partly cloudy skies, though an isolated shower still cannot be ruled out. Due to the increased sunshine, shift in wind direction to the SW, and warmer temperatures aloft, Monday will bring warmer temperatures than those of Sunday, reaching the upper 70s inland, upper 70s to lower 80s in the immediate NYC area, and the mid to upper 70s in Long Island/S CT. Tuesday will continue with the warming trend, with temperatures in the upper 70s to lower 80s inland, lower to mid 80s in the immediate NYC area, and the upper 70s to lower 80s in Long Island/S CT.

A strong cold front will move through the region on Wednesday, which will push the warmth out. The front is expected to move through late enough in the day to keep temperatures warm during the day on Wednesday, similar to those of Monday. The latest models have trended significantly drier for this front, and some fail to show any precipitation in the area. For tonight's forecast, I kept a risk of scattered thunderstorms, but widespread heavy thunderstorms are unlikely from this front.


Thursday - Sunday: First Taste Of Fall

While the front on Wednesday will push the warmth out, the cold will not move in until Thursday night. As a result, Thursday will bring partly sunny skies with colder temperatures, reaching the upper 60s inland, lower 70s in the immediate NYC area, and the upper 60s to lower 70s in Long Island/S CT. A few mid 70s may be possible in the immediate NYC area. At that time, a strong trough will move into the region, with 850 mb temperatures below 0 degrees celsius covering much of the Great Lakes. This cold air mass will shift to the southeast, covering the region on Friday and Saturday. With a high pressure moving into the Northeast, dry conditions are expected for Friday, and high temperatures will be chilly, only reaching the lower to mid 60s inland and the mid to upper 60s in the immediate NYC area, Long Island and southern Connecticut.

By Friday night and the weekend, however, there is some uncertainty. While most of the models show the high pressure starting to move out with dry conditions staying in place, the latest GFS runs have trended towards showing a coastal low pressure developing around Friday night/Saturday, which would bring mainly cloudy skies and potentially showers into the area, with high temperatures potentially staying below the 60 degree mark. This is only a new trend which started showing up on one model, and it will be watched in case it becomes more likely. Should the original scenario where the high pressure sticks around verify, temperatures on Saturday will still be chilly, with high temperatures in the lower to mid 60s across most of the area, and low temperatures in the lower to upper 40s across most of the area except for NYC. Stay tuned for more information on this cool spell and the forecast for next weekend.