NAM Model showing weak high pressure keeping the weather fair on Tuesday.

A ridge of high pressure in the mid levels of the atmosphere is building in this morning, and will continue to do so throughout the day on Tuesday. The result will be pleasant weather, with clear skies and high temperatures in the low 60's. Winds will be out of the northwest behind a weak cold front that passed the area late Monday Night into Tuesday morning. The winds could be a bit breezy and gusty, mostly during the afternoon. It's a result of what is technically called "cold air advection" or "CAA". Behind a cold front, northwest or west winds usher in a new and cooler airmass, and the advection of this air behind a temperature boundary can often bring some moderate wind gusts. Tuesday will be no different. Low temperatures overnight Tuesday Night into early Wednesday Morning will likely dip into the middle 40's once again, as clear skies and light winds will allow for favorable radiational cooling conditions. However, by early Wednesday morning (possibly even the pre-dawn hours) clouds will begin to increase, owing to a system developing to the west of our area. This system looks to provide a very complicated scenario during the second half of the week. Keep reading for all of the details.

THE FORECAST...
Today (Tuesday): Mostly sunny, with a high near 64. Northwest winds 10 to 15 mph.
Tonight: Partly cloudy, with increasing clouds late. Low near 48. Northwest winds 5 to 10 mph.

LATE WEEK EVENT COULD PROVE TROUBLESOME (AND CHILLY):

NAM Model showing potential for some frozen precip in the interior Thursday evening. Notice the surface temps in the 30's(left) and moderate precip (right) Also notice warmer temps near the coast & city.

 The pleasant weather of the beginning of the week will become somewhat of a distant memory as we approach Wednesday, and continue through Thursday. A strong gradient in the mid levels of the atmosphere will develop across the Northeast by the end of the week, and the gradient will eventually extend down towards the surface in the form of a well defined frontal boundary, which will settle near the area by Thursday morning. This frontal boundary will serve as a "highway" for low pressure and moderate to heavy precipitation to develop at the surface, as a strong disturbance moves over the boundary in the mid and upper levels of the atmosphere. Such a development would most certainly bring a threat of moderate to heavy precipitation to the forecast area, beginning on Thursday and continuing through Thursday evening. 


Making the situation more complicated is the intrusion of significant cold air which is expected behind the cold front. This will bring colder temperatures into the system on Thursday, and the potential would exist for some frozen precipitation (yes, we're serious) in the higher elevations and the distant interior. Such an event would be isolated and likely confined to the higher elevations, but it's definitely worth mentioning. To be clear, we aren't expecting anything frozen in the city or immediate suburbs, but if you live in Northwest NJ or the higher elevations of Connecticut or Southeast New York, you may want to keep a very close eye on this system for the potential for snow as the system winds down Thursday Night. 


Either way, behind the front, we're expecting some of the coldest air so far this fall. This weekend looks to provide more dramatics, as the boundary settles offshore. Forecast models are beginning to hint at the potential for a nor'easter developing along the front on Saturday. We'll keep you updated during the week as we get a better idea of what's going to transpire.


Article written by JH. Published October 25th, 2011 at 12:04am. Looking for a forecast? See New York Metro Weather's Long Range Forecast for the upcoming work week, or view our Technical Forecast Discussion for the more serious weather enthusiasts. Also, check out our new Forecast Overview tab. For up to the minute details on forecasts, watches, warnings, and alerts, follow us on Twitter and Facebook.