Oct 5, 2012: Rain Returns This Weekend

Forecast Highlights:

- Cold front comes through Saturday, chilly rain on Sunday
- Colder start to week, frost possible inland
- Brief warm up towards mid next week with showers possible
- Another cool down expected by late next week

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The 5-Day Forecast has been updated for the area tonight.
 
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Weekend Outlook: Warm, Then Cold and Rainy

A cold front currently entering the region will move through the area during the late afternoon and evening hours on Saturday, bringing a much colder air mass behind it. Another warm day is expected ahead of the cold front with temperatures rising into the low to mid 70s inland and the mid to upper 70s across the rest of the area. Parts of NE NJ may reach and/or slightly pass 80 degrees. Breezy winds are expected, starting from the SW and turning west as the cold front comes through. Most of the shower activity is expected to dissipate before reaching the area, although scattered showers are still possible by the late afternoon and evening hours especially north and west of NYC.

Some locations will experience a relatively sharp drop in temperatures following the front in the late afternoon and evening, especially towards NW NJ/SE NY and the Hudson Valley, where temperatures should drop from the low 70s to the 50s, then gradually cooling overnight to reach the upper 30s to low 40s. The rest of the area should see more of a gradual drop in temperatures, eventually dropping into the mid to upper 40s for most locations with upper 40s to low 50s in NYC.

A weak coastal low will develop along the cold front and quickly move northeast, setting up for a chilly rain event on Sunday into Sunday night. The model guidance has trended drier with this wave, with at least 1/4 to 1/2 inch expected. Most of the showers are expected after the late morning/early afternoon hours through the rest of the day into the early overnight hours. Temperatures will peak early in the day, reaching the low to mid 50s inland and the mid to upper 50s across the rest of the area. Parts of Long Island may reach the low 60s before the rain begins. The showers will last through the early overnight hours, towards 10 PM-1 AM, with overnight lows dropping into the mid to upper 30s inland and the low to mid 40s for the rest of the area except for NYC, in the mid to upper 40s.


Next Week: Cold, Warmer, Then Colder

The current pattern will continue through the majority of next week with a persistent trough over Canada and a strong block off the coast of the western US keeping the central and eastern US generally colder than average. Chilly temperatures will stick through Monday, with highs in the mid 50s inland and the upper 50s to low 60s across the rest of the area. Drier conditions are expected with partly sunny skies. Cold overnight lows are expected again, similar to those of Sunday night although perhaps a degree or two warmer. Heights will rise on Tuesday and Wednesday ahead of a shortwave moving towards the Great Lakes, with highs returning into the low to mid 60s on Tuesday and the mid to upper 60s on Wednesday.

A cold front will move through the region on Wednesday, producing some showers followed by another round of cold temperatures. Temperatures on Thursday are expected to cool back down into the upper 50s to low 60s for most of the area, with mid 60s possible in the immediate NYC area, although at this time it appears that the coldest temperatures will come down behind another shortwave on Friday. The GFS and ECM especially show a strong blast of cold air, with temperatures dropping into the 20s for lows across the Northeast with widespread 30s across the area. While these two models may be a bit overdone with the intensity of the cold, which is a typical bias this far out, this time frame will be watched for the potential of the first widespread frost event of the fall.


Long Range Update: Warming Up

A strong rex block feature off the western US coast will begin to break down by late next week as lower heights return to Alaska and the pattern becomes less amplified. Following the late week to early weekend cool spell, a moderation in the current pattern is expected with the eastern half of the US warming up, although New England should continue to see chilly temperatures. There is uncertainty regarding the duration and extent of this warmer pattern, although this warmer period, along with exactly how cold next week turns out to be and what happens by the end of the month, should ultimately determine whether October ends up warmer or cooler than average.