Nov 4, 2010: Cold Weekend, Then Much Warmer

The storm has ended for most of the area, as the low pressure continues to move NE and the western end of the rain pushes east, which is already east of NYC. A few showers are still expected tonight, but any shower will be light. A strong trough currently in the north central US will continue to drop south while moving slightly to the east, which will lead to much colder temperatures for Saturday and Sunday, similar to those we saw on Monday and Tuesday, but afterwards a warm spell will likely follow as a southeastern ridge sets up for a few days.

Tomorrow’s Outlook:

Despite mainly cloudy skies and isolated showers tomorrow, temperatures will be slightly warmer than today, with high temperatures in the upper 40s inland, lower to mid 50s in the immediate NYC area, and mid 50s for Long Island/S CT. The best chance of rain will be tomorrow morning in eastern Connecticut/Long Island. A west wind is expected during the day.

Friday Night – Sunday: Cold, Potential Flurries Inland

Friday night will bring a much colder air mass, with low temperatures dropping into the upper 20s to lower 30s inland, lower to mid 30s for the north/west suburbs of NYC, and the upper 30s in NYC. Cloud cover will be present at that time, with lake effect snow expected in western NY/PA, and it is possible that scattered showers fall in the area on Friday night and Saturday, focusing on the northern and western parts of the area. With the temperatures mentioned above, some of these showers could fall as snow showers, especially in Sussex/Orange counties.

Saturday will have high temperatures in the mid to upper 40s inland and upper 40s to lower 50s for the rest of the area, as the strong trough starts to move towards the area, but it won’t be able to advance too far east, and with an approaching low pressure to the west of the trough, it will weaken on Saturday night while slowly shifting east, leading to cold overnight lows similar to those of Monday morning, but not as cold as the temperatures could’ve been if the set up was closer to what was indicated several days ago.

Sunday will see slightly colder high temperatures, in the lower to mid 40s inland and in the mid to upper 40s for the rest of the area. The air mass will start to moderate as the trough weakens, but an approaching storm will keep the cold air around a little longer.

Monday And Tuesday: Still Chilly, Significant Maine Storm

Once the current storm moves out of the region, a train of moisture will set up in the western Atlantic, sending heavy rain from Tropical Storm Tomas to Nova Scotia. While Tomas’ track is uncertain, either an extra-tropical Tomas or another low pressure forming along this boundary will likely start becoming negatively tilted, and will peak in intensity and stall somewhere near Nova Scotia or Maine on Monday. This would bring moderate to heavy rain and some snow to these areas, while the area stays dry with the cold air mass still persisting, but not as cold as it will be on Saturday/Sunday. As the storm starts to exit on Tuesday, the trough will exit the region, leading to a warm spell that will last for several days.

Wednesday – Saturday: Warmer, 60+ Degrees Return

On Wednesday, a weak storm will be present in the Midwest, with a high pressure near the Mid Atlantic, leading to a ridge building across the entire East Coast, with 850 mb temperatures between 10c and 14c. This will lead to much warmer temperatures, with highs likely returning into the 60s for most of the area.

The weak storm in the Midwest will try to pull a trough towards the region, but it will not be strong enough to pull down the trough into the region, leaving high temperatures in the 60s, potentially into the 70s up to the central Mid Atlantic. With the eastern ridge still holding strong, another storm may then form in the central US and head towards the Great Lakes or Midwest, which would lead to even warmer temperatures on Friday, with high temperatures potentially reaching the lower 70s as far north as NYC.

What happens afterwards is still uncertain, but at this time there are two main possibilities. One is that the storm pulls down colder air, but the cold air will not be able to reach all the way to the coast, and another storm but further east will be able to push the cold air further east. The other possibility, suggested by the ECMWF, is that the ridge holds steady in the East, and the third storm would also track through the Midwest. As this is still in the longer range, there is still a lot of uncertainty, and it is possible that other solutions could be introduced for this time frame. Stay tuned for more details on this time frame.

Leave a Reply