Oct 4, 2011: Cold Ends; 80+ Degrees To Return

Last night, the cutoff low started to move towards New England, producing light to moderate rain over Long Island and southern Connecticut which brought between 1/4 and 1/2 inch of rain to those areas. With mostly cloudy to cloudy skies, today brought chilly temperatures, though temperatures were warmer than expected, with high temperatures reaching the mid 60s from NYC and further west, and the lower to mid 60s in Long Island and southern Connecticut.

As the low pressure drifted into New England today, the rain finally exited the area today, marking the start of a long stretch of dry weather; the next chance of rain will not be until the end of next week. Warmer temperatures will briefly return tomorrow, with high temperatures reaching the 70s across the area, though a colder air mass will return for Thursday and Friday, with frost likely in the interior parts of the area. The cold will only be brief, however, as a significantly warmer air mass will spread into the region, resulting in much warmer temperatures, passing the 80 degree mark in parts of the area.


Tomorrow's Outlook:

As the cutoff low moves towards Nova Scotia while intensifying, it will pull a strong cold air mass into the Northeast. The cold will not quickly enter, however, and ahead of the cold surge, a brief warm up is expected during the day on Wednesday. With a breezy NW wind expected, gusting up to 25-30 mph, high temperatures will peak in the upper 60s to lower 70s inland, lower to mid 70s in the immediate NYC area, and the lower 70s across most of Long Island and southern Connecticut.


Thursday - Friday: Cold, Frost Likely

The cold air mass previously mentioned will move into the Northeast on Wednesday night through Friday. This will bring much colder temperatures into New England, but with the low pressure well to the northeast of the region, over Newfoundland, the cold will focus over the Northeast, with the NYC area on the western edge of the cold. Meanwhile, a strong high pressure will move into the Northeast, providing the region with a stretch of sunny skies and dry conditions. The clear skies and light winds will result in overnight radiational cooling, which will likely result in frost in the interior parts of the area.

Thursday will bring sunny skies across the area with colder high temperatures, reaching the lower 60s inland, lower to mid 60s in the immediate NYC area, and the upper 50s to lower 60s across most of Long Island and southern Connecticut. Cold temperatures are expected for Thursday night, with low temperatures dropping into the mid to upper 30s across most of northern NJ, SE BY and southern Connecticut, except for the immediate north/west suburbs of NYC, which should stay in the lower 40s. Long Island will likely see lows in the upper 30s to lower 40s, with lows in the mid to upper 40s in NYC. The cold air mass will moderate on Friday, with highs reaching the mid 60s from NYC and further west, and the lower to mid 60s in Long Island and southern Connecticut.


Next Weekend - Next Week: 80+ Degrees Return

As the high pressure settles over the region, the clockwise motion around the high pressure will bring a warm west wind into the region, with a much warmer air mass in the west/central US shifting east to cover the entire eastern half of the United States by Saturday and Sunday. Temperatures will slightly warm up on Saturday, reaching the mid 70s in the immediate NYC area. Sunday will be the warmest day, however, with west winds, sunny skies, and 850 mb temperatures near 14-16 degrees celsius. These conditions will bring high temperatures into the upper 70s across most of the area, with lower 80s expected in the immediate NYC area, which is at least 10-15 degrees above the average for this time of the year. It is not out of the question that parts of the immediate NYC area may get close to or reach the 85 degree mark in the warmer case scenario.

The pattern setting up for next week includes a negative PNA, with a trough over the west coast. Along with the -PNA, however, a neutral NAO is expected. Typically, a positive NAO would be needed for the entire East Coast to see the warmth persist. With the neutral NAO in place, a trough will affect parts of New England around early-mid next week, which will bring cooler temperatures further north, but the warmth will persist over the NYC area, with temperatures staying around the mid 70s, which is still nearly 10 degrees above average.

By the second half of next week, however, the high pressure will likely weaken and start to drift further east. Meanwhile, tropical developments are possible over the Gulf of Mexico, where the next tropical system of this year's hurricane season may develop and move towards the US coast. There is a lot of uncertainty on this time frame, but the potential is there for widespread rain to return into the region late next week into next weekend associated with this potential tropical disturbance. Stay tuned for more information on the longer range.