Thursday, November 18, 2010

Nov 18, 2010: Stormy And Colder Thanksgiving Potential

Note: The 5-Day Forecast was updated for the immediate NYC area only.

-----------------------------------------------------------

Today started out as a mostly sunny day but clouds increased later on in the day, with high temperatures peaking in the mid 50s inland, mid to upper 50s in the immediate NYC area, and in the mid 50s for Long Island/S CT. An isolated shower was reported across parts of the area, but for the main part no more than a trace of rain was recorded.

Tomorrow will turn much colder for the area, with Saturday slightly warming up and Sunday cold again, with temperatures warming up for early next week. Afterwards, however, indications are that the pattern could get stormier, leading to a potentially stormy Thanksgiving day, then cold Thanksgiving weekend.


Tomorrow's Outlook:

Mostly sunny skies are expected for the area tomorrow, along with a north wind turning west. As a colder air mass reaches the area, with 850 mb temperatures near -6c, temperatures will be much colder tomorrow, with highs in the lower to mid 40s inland, mid to potentially upper 40s in Long Island/S CT, and in the mid to upper 40s for the immediate NYC area.

Looking across the rest of the Mid Atlantic and Northeast, cold temperatures will be in control, with high temperatures in central/northern Maine below freezing. Places such as Virginia will see highs in the mid 50s.


Weekend Outlook: Warmer Saturday, Cold Sunday

On Saturday, a weak low pressure in southern Canada will move into Maine, leading to light snow in that area, with the storm pushing out the trough and briefly bringing a warmer air mass. This will lead to high temperatures in the lower to mid 50s inland and in the mid to upper 50s for the rest of the area with a SW wind expected.

The storm's cold front will then push through for Saturday night, bringing a much colder air mass into the Northeast with the area in the bondary of the cold temperatures of the north and warmer temperatures to the south. Overnight temperatures on Saturday night should be very cold, in the lower to mid 20s inland, mid 20s to lower 30s for the north/west suburbs of NYC and southern CT, and mid to upper 30s in NYC.

Sunday will be another cold day for the area, especially further north, with high temperatures in the lower to mid 40s inland and in the mid to upper 40s for the rest of the area.


Monday - Wednesday: Mild Start To The Week

On Sunday night, a weak low pressure in the Midwest moving northeast into Canada will push the cold air out of the region, with a high pressure near Maine moving towards the Southeast coast. As a result, Monday will be warmer for the area, with high temperatures generally in the mid to upper 50s with a SW wind expected. Meanwhile, a low pressure will be organizing close to where the first one will on Sunday, and will move NE.

On Tuesday, a high pressure is expected off the SE coast, however with a -NAO, this will be blocked from becoming a widespread warm spell. A cold front related to the second storm will approach the area, bringing a risk of showers into Tuesday night. Meanwhile, a strong polar air mass will be dropping into the Midwest, bringing sub-zero temperatures to those areas, and a low pressure could form near Colorado that may be the makings of the next storm to affect the area.

The cold front will bring colder temperatures into the area for Wednesday, however the cold air mass will not be able to advance much further east due to the next developing system.


Thanksgiving Weekend: Stormy, Then Much Colder

As mentioned over the last several days, there is the potential for a storm to affect the region during Thanksgiving day, potentially lasting into Friday. Yesterday, some models hinted at strong suppression and snow potential, however this seemed unlikely, and the models are now showing an inland track. Given that this is in the longer range, there are likely to be some changes, but with a generally warm SE and a strong cold air mass in the north central US, I am thinking at this time that this storm could track inland, somewhere near the Great Lakes or the Northeast, pulling in a warmer air mass into the area for Thursday or Friday depending on the timing. The models are also hinting at the storm making an energy transfer to a low off the New England coast, and this potential will be watched.

Whether the west or east track verifies, this storm could be a potentially strong one, with large impacts, including thunderstorms and potentially severe weather to the south of the storm, strong winds, and potentially heavy snow to the northwest of the storm. Behind the storm, the strong cold air mass could be directed at the region, and with a strong -NAO and a moderating -PNA, there is the potential for much colder temperatures to affect the area during the weekend. Stay tuned for more details on this time frame.

2 comments:

  1. Would be very interesting to see what happens if energy is transferred off to coast...can't wait for another potential storm on 28th

    ReplyDelete

Appropriate and subject relevant comments are welcome. Comments that are non-weather related or contain arguments with no legitimate reasoning to back up their claims are not tolerated and will be moderated and deleted.