Nov 11, 2011: Warmth To Return Tomorrow

Behind last night's cold front, the ridge over the region was replaced by a strong trough, with partly sunny skies and windy conditions observed today. With the trough in place, colder high temperatures were observed, only peaking in the mid to upper 40s inland, upper 40s to lower 50s in the immediate NYC area, and the lower 50s across most of Long Island and southern CT. Wind gusts ended up in the 30-40 mph range across most of the area as expected.

This trough is only making a brief appearance in the area, however, as a stronger ridge will build back into the region tomorrow and on Monday, bringing well above average temperatures across the region once again. A cold front will approach the area on Tuesday, bringing showers to the area especially between the afternoon and the overnight hours, and while colder temperatures will return behind the front along with drier conditions, the pattern will remain unfavorable for any sustained cold to develop in the northern US.


Tomorrow's Outlook:

With the trough moving out, 850 mb temperatures will warm up, passing the zero degree celsius mark. With a breezy SW wind expected along with mostly sunny skies, surface temperatures will warm up as well, reaching the mid 50s across most of the area, with a few upper 50s possible in parts of the immediate NYC area. Wind gusts are expected to reach the 20-30 mph range across most of the area.


Next Week: Warming Up, Some Rain, Then Colder

The current pattern with a strong -PNA, going off the charts, as well as an east based -NAO, is unfavorable for cold setting up over the northern US, and this appears to be the case once again, as another trough dropping into the western US will result in a ridge building into the region once again for Sunday and Monday. This will bring mostly sunny skies on Sunday with highs in the upper 50s to lower 60s across the area, and partly to mostly cloudy skies across the area on Monday with highs in the lower to mid 60s across most of the area. Parts of the immediate NYC area may reach the upper 60s if there is enough sunshine, which would end up nearly 15 degrees above the average high temperature for this time of the year.

A cold front will approach the region on Monday. Yesterday's models were faster with the front, with the GFS bringing it through on Monday, although today's models trended slower, and are now in agreement with showing the front moving through on Tuesday night. As a result, temperatures will remain in the lower to potentially mid 60s across most of the area on Tuesday with showers expected between the afternoon and overnight hours. Light to moderate rain is likely to fall across most of the area, although no significant rainfall amounts are expected.

Behind this front, cooler temperatures will gradually return. High temperatures are likely to cool down into the lower to mid 50s across most of the area between Wednesday and Friday, and one of these days may end up with temperatures in the mid 40s to lower 50s although the exact timing is uncertain, depending on a potential weak low pressure in the Northeast that some models show on Thursday. This potential low pressure won't bring more than a few rain showers to the area, although it would bring slightly warmer temperatures on Thursday with colder temperatures on Wednesday and Friday. This cold spell will not be sustained as well, and another ridge could build again by next weekend with warmer temperatures. Stay tuned for more information on the outlook for next week.


Longer Range: Will The Cold Set Up?

Over the last several days, there have been indications that a more sustained cold pattern could build towards the end of the month. The PNA, although currently very negative, is shown to trend closer to neutral, allowing for a weaker ridge in the eastern US, with a trend towards a slightly negative NAO in the longer range and the MJO trending towards phases 1-2, as well as building strong cold air in western Canada. There are more indications, however, that the pattern may not change as early, with the Pacific pattern potentially remaining unfavorable for strong cold dropping into the US through the rest of November, and there are already some similarities appearing compared to the winter of 2001-2002, which brought very little snow to the NYC area. I am not expecting this winter to end up nearly as snowless as that winter did, and a cold and snowy December is still a reasonable possibility, although the possibility that a colder pattern may fail to materialize for December cannot be ruled out. Stay tuned for more information on the longer range with updates over the next few days. The outlook for December will be discussed in more details with my final winter outlook, which will be posted on Sunday, 11/20.