[notice]Note: Blog updates are suspended this week, check next post for more information. The next update will be posted on Friday, 10/18/13.[/notice]
An inactive pattern continues into this week; other than scattered showers on Thursday and Friday, no significant rain event is in sight over the next 7-9 days. Temperatures will generally remain above average this week, gradually cooling down into the weekend and next week but with colder temperatures likely to struggle persisting over the region.
This Week: Generally Dry, Mild; Late Week Showers
As the high pressure that was in place gradually exits, temperatures will slightly warm up tomorrow, with highs expected to return into the upper 60s to low 70s for most. Increased cloud cover is expected on Wednesday into Thursday as a storm system approaches the region but generally misses the area, with isolated showers possible towards eastern Long Island/CT during the day on Wednesday and rain from the cold front brushing northwestern parts of the area overnight; rain totals are generally expected to remain below 0.1 inch, locally up to 1/4 inch inland. High temperatures on Wednesday are again expected to reach the upper 60s to low 70s for most, as with Thursday but with more widespread low 70s in the immediate NYC area. The main uncertainty in the forecast is a strong shortwave trough that moves through on Thursday night into Friday morning; while at this time, no significant precipitation is expected, a wave of light to perhaps moderate rain could affect the area on Thursday night, with up to 1/4 inch possible. More information will be posted on this possibility with Wednesday’s forecast update. Drier conditions will return for Friday with more sunshine and highs in the 65-70 degree range for most.
Weekend – Next Week: Cooling Down
Towards next weekend, a more significant pattern change will unfold as strong ridging develops towards the northeast Pacific Ocean and western US, along with blocking near Greenland, which helps to set up a trough axis near the central US with a more significant cold air mass reaching the US for the first time since late September. Temperatures will cool down towards average across much of the region, although the core of the cold air and coldest anomalies are expected to remain west; with the high pressure placement south of the area, leading to a west-southwest flow both at the surface and up to the mid-upper levels, the cold air masses will initially struggle to move into the region before being removed, and eventually the colder temperatures are likely to spread in towards the last week of the month, but may be relatively short lasting. As such, I am siding warmer with a delayed entrance to the cold air than the model guidance at this time.
The first surge of cooler air takes place on Sunday and Monday, with 850mb temperatures falling to near zero Celsius. After another partly sunny day on Saturday with highs likely in the 65-70 degree range for most, cooler temperatures are expected for Sunday and Monday, but with continued west-southwest winds, temperatures are not expected to end up much below average, likely in the mid 50s-low 60s range for highs, and the 30s inland and 40s near the coast for lows. These temperatures, despite only being slightly below average, are still expected to be the coolest so far this fall. A brief warm up is expected early-mid next week ahead of the next frontal passage, which is when the next widespread rain potential may take place, with a stronger trough and colder temperatures possible towards late next week and next weekend, even if only for a brief period of time.
<< October 11 | October 12 | October 13 | October 14 >>
Sunday, October 13 Observations:
With a Canadian high pressure building into the region and a continued northeast wind, temperatures cooled down into the mid 60s across the area, ending up cooler in the eastern half of the area compared to locations further west; dry conditions continued again as the coastal low was suppressed entirely south of the region. The highest temperature was 68 degrees in Somerset, NJ and JFK airport, and the lowest high temperature was 62 degrees in Montauk, NY and New London, CT.