Sept 6, 2013: Warmer Temps, Rain Return Next Week

[notice]The 5-Day Forecast page has been extended with an experimental 7-day forecast. More information can be found here.[/notice]

Forecast Highlights:

gfs_namer_144_850_temp_mslp_precipA chilly air mass is currently present over the region, with mainly clear skies and chilly temperatures observed this morning and chilly highs expected today. A similar cool down will repeat for Sunday night and Monday, but with the pattern trending warmer for mid next week, when a warmer and more humid air mass will make a brief return, followed by a frontal passage towards Tuesday when the next risk of widespread showers and thunderstorms is likely. A brief cool down may follow, but with indications pointing to a warmer mid-late September pattern.


<< September 4 | September 5 | September 6 >>

Thursday, September 5 Observations:

9.5.13A strong but moisture starved cold front moved through the area on Thursday morning, bringing a much cooler and drier air mass from the north, with a breezy north wind and mostly to partly sunny skies observed across the area. A temperature gradient set up from interior regions to the coast, with highs in the low-mid 70s inland, mid to upper 70s in northern NJ and southern CT, and the upper 70s to low 80s in NYC and Long Island. The highest temperature was 82 degrees in JFK airport, and the coolest high temperature was 70 degrees in Port Jervis, NY.



Today – Monday: Chilly Today, Warmer Weekend, Then Chilly Again

A fluctuating temperature trend will unfold over the next four days as the pattern aloft ranges from a strong trough, to a brief surge of a warmer air mass, to another quick yet strong trough. A broad Canadian high pressure will move through the area today, resulting in mainly sunny skies, light NW winds, and highs reaching the upper 60s to low 70s inland and the low to mid 70s for the rest of the area. The cool air mass aloft will be quick to move out, with 850mb temperatures warming up from nearly 4C this morning to 10C tonight, but with mostly clear skies and radiational cooling to result in another chilly night, with lows falling into the low to mid 40s inland, upper 40s to low 50s in the north/west suburbs of NYC, southern CT and Long Island away from the coast, and mid 50s in NYC and the immediate coast. As the high pressure shifts east of the area, a southwesterly wind will return for Saturday with mostly sunny skies and warmer temperatures returning, peaking in the mid to upper 70s across the area, reaching 80 degrees near NYC.

A scenario quite similar to that of Thursday and today will repeat again on Sunday-Monday, as a strong cold front moves through the area on Sunday ahead of a strong yet quick moving trough entering the region overnight into Monday, bringing another brief round of much cooler temperatures. Partly sunny skies are expected on Sunday with isolated thunderstorms possible with the frontal passage in the early afternoon, especially north of NYC, with a breezy NW wind at 10-15 mph and temperatures peaking in the mid 70s inland, upper 70s in northern NJ, south CT and Long Island, and the low-mid 80s near and southwest of NYC. As the high pressure builds in, clearing skies and decreasing winds are expected with lows similar to those of this morning, in the low 40s inland, mid to upper 40s in north/west suburbs and southern CT, upper 40s-low 50s in LI, and low-mid 50s in NYC and the coast. Mainly sunny skies are expected on Monday with highs in the upper 60s-low 70s inland and the low-mid 70s elsewhere.


Tuesday – Friday: Warmer Temps, Humidity, Storms Return

Monday’s high pressure will shift east on Tuesday, setting up for a southwest wind and warmer temperatures, repeating tomorrow’s forecast as today’s high pressure exits to the east, with highs returning into the mid to upper 70s. Unlike this weekend, however, there will not be another strong incoming trough. A pattern change will begin to develop in North America as strong troughing lifts out of eastern Canada and into Greenland, allowing for a shortwave in the northwestern US to track east into the region and amplify, shifting ridging into the eastern US as well, bringing a warmer and more humid air mass into the region as 850mb temperatures climb into the 16-18C range and dew points return into the mid-upper 60s.

Partly sunny skies are expected on Wednesday with highs reaching the low to mid 80s across the area, with humidity increasing overnight as lows struggle to fall below the 65-70 degree range. A cold front is expected to move through on Thursday; there is some uncertainty regarding the amplification and timing of this trough, with some changes in the outlook possible, although highs are likely to reach the low 80s again on Thursday with increased cloud cover and scattered showers and thunderstorms associated with the frontal passage. A brief cool down is likely for next Friday and Saturday, with temperatures possibly similar to those of today. More information on the longer range pattern, including a likely warmer pattern beyond next weekend, will be posted with a medium-long range outlook later today.

Leave a Reply