Saturday, December 3, 2011

My Delaware Valley Forecast for Dec 3rd - Dec 9th. Big Changes to follow Folks !

Issued Saturday 12-3-2011
Delaware Valley Forecast and Discussion.
For Saturday 12-3 through Friday 12-9

The promised pattern change is on the way, but first this very old and present pattern will give the heat misers one more stretch of mild weather. Then old man winter comes a knocking later in the week. We start the weekend out on a chilly note today, but Mostly Sunny, with Highs only near 50.

High Pressure moves off the M/A coast tonight, but expect one more cold night with lows in the 30's. The return flow around this High, will bring a Southwest flow of milder air for both Sunday and Monday. Both days will remain dry, with moderating temperatures. Highs on Sunday will be in the Upper 50's and even milder on Monday, with Highs in the low 60's. Expect Partly Sunny Skies both days. Lows in the Upper 30's to mid 40's.

As we get into the middle of the week, things turn wet, but remain quite mild. A strong but slow moving cold front will be approaching the region from the Midwest on Tuesday and Wednesday. Ahead of this front a SW flow of mild and increasingly moist air will take over. Some light rain will move in during Tuesday afternoon and continue into much of Wednesday. Highs both days will be near 60 and lows in the 40's.

A weak area of low pressure will develop along this front and move NE during Tuesday into Wednesday. As this occurs a more steady period of rain is likely from Later Tuesday night into Wednesday morning, then this steadier rain should taper off to some showers during Wednesday afternoon and evening before ending.

Finally our slow moving cold front reaches the coast later in the day on Wednesday, as the colder air filters in behind the front during Thursday. It's at this point the pattern change really begins and it's effects will result in seasonably cold weather for later in the week. Windy and colder weather takes hold to close out the week, with highs only reaching the Upper 40's on Thursday and low to mid 40's on Friday.

Next weekend into the following week is where we get progressively colder as the pattern change gets underway ! I've been advertising this for some time now, with the promised changes coming between the 5th and 15th of this month. The entire H5 pattern is beginning to change now further west and in the Pacific, and the results will be felt here in the east after the 7th. A progressively colder weather pattern with continue into at least mid month as a large PV sets up in Central Canada and moves slowly east. This will place a large trough over the Central and Eastern US resulting in much colder weather. Though this will not be bitter cold air, I do expect temps to average below normal between the 10th and mid-month.

For now, this is where I take this call, but it does appear this colder pattern will be sticking around for a while and no signs of any big warm ups in the mid and longer range after this pattern changes around the 8th. The question of does it snow during this time, continues to be ask. It's too early to determine for sure, but with this pattern change, we should get cold enough that some mixed precip, and or minor snow events, can't be ruled out. I'll tackle this with more thoughts later in the week, with a new post and update !

Take Care,


Happy Elmer Fudd said...

Thank You ..Good it's not bitterly cold yet cause its rabbit season. !!!!

Well Red said...

Hi John - DO you see the rain pushing out of here by the weekend of the 10th? I have been hearing reports of a "noreaster" possibly next weekend with the cold setting in.... any thoughts on that?


There's a s/w and second stronger cold front coming down with clipper type system towards next weekend. Some mischief is possible. Could transfer to Miller B for New England and wrap up there. Probably to far north for us M/A folks but some wintry precip can't be ruled out and even colder air drilling behind this system. Like I said too early for details, but has potential with new pattern. Will have more on this later in the week.