Wednesday, January 7, 2009

A Pattern Change to Much Colder Weather Is On The Way ! The First Snowfall Of The 2009 New Year Looks More Promising for Saturday & Again Next Week.

Wednesday: 1/07/2009:
Discussion & Some thoughts into next week.
For the Delaware Valley and M/A States.

Turning much Colder towards Mid-Month, as snow threats increase. This all starts Saturday, and again on Tuesday, from Clipper Systems.

An Overrunning/Deep Southern System, and a much bigger snow threat comes later next week, as "Broad Based/Full Latitude Trough" settles in to the Central and Eastern CONUS during the week. This new pattern brings the Coldest Air mass of the 2008-2009 Winter Season.

So here we go folks, it's time to get the 2008-2009 Winter Season going. All prime factors for the Delaware Valley and M/A States are now gradually falling into place as forecasted. We now have Climatology on our side, The Ocean Water temps are in the Upper 30's to near 40. Key Teleconnections with a more favorable Pattern, are soon to kick in with a big change to Colder weather, and some much better snow chances as we head into next week. Earlier in the week I mentioned a snow threat for this upcoming weekend (Saturday) This event appears to be another minor event with some snow and mixed precip. At this time I'm thinking we have a shot at some accumulations.

A rather strong Clipper system and it's associated Cold front, will be swinging through our region for Saturday and Saturday evening. A good consensus I'm using for the track of this storm, is across the lower Midwest Friday, to Southern OH/WV on Saturday AM, then to near the DE/NJ coast later Saturday afternoon. This track is most favorable for accumulating snowfall near Philly and points north, with some snow and mixed precip, over PHL/DE/ and Southern NJ.

My best estimate at this time, is for periods of snow to move in later Friday night and early morning on Saturday, this snow will continue into Saturday afternoon with a more steady period of accumulating snow towards mid-day and the early afternoon hours. Snow could be mixed with some rain over parts of DE and Southern NJ as temps will be marginal in the upper 30's for a short time. A burst of snow is also possible with the strong cold front and Cold Air advection which follows during the afternoon and early evening hours on Saturday.

A general 1" to 3" of snow is possible for the entire Delaware Valley, includes: (SE PA, Southern/Central NJ, and Northern DE, for Saturday. All snow ends towards evening, then turning windy and much colder Saturday night and Sunday.

2" to 4" amounts are possible: From the Lehigh Valley/Pocono's, and into NW NJ.

Much Colder and windy weather follows from Saturday Night into Sunday. The cold weather continues into Monday and Tuesday, and yet another Clipper system approaches for Monday Night and Tuesday, with more snow possible. The Coldest air mass of this winter season will then follow, for the middle and end of next week.

I'll have much more on these threats later on, but I'm confident that a much colder pattern and snow chances will increase for next week, starting with the Clipper on Tuesday and a bigger threat possible towards the end of next week. We're on our way Folks !

Take Care,

Some verification and an update for a previous call:
Please see the link below from my writeup on Dec 23, 2008. I had some thoughts for Jan 1-15 and the pattern, which see to be on target so far. I mentioned the first week of January will be stormy and active, but the second week is where the teleconnections and pattern change really kicks in for the M/A/ Snow chances will be best in this time frame. I think this still has a shot to verify and some Arctic Air ans snow chances are looking good for next week.

Some Mid-Range thoughts into the New Year 2009:
January 1st thru 15th.
(A quote from my Dec 23 writeup) Below

The first week of January we continue an active and stormy pattern for much of the Eastern US. I look for the jet stream and the overall pattern to gradually change. More persistent cold and a trough in the East will return, and snow chances for the Mid-Atlantic States will increase during this first week.

I'm more confident that the second week of January is where the pattern change and Neg NAO signal become more established. It's between the 5th and 15th of January where I'm thinking we see our first real shot at a snowstorm in the M/A States and Delaware Valley regions. Stay turned as I'll have better details, and more updates on these changes as we draw closer to the New Year.

Take Care,


Anonymous said...



Saturday is a very close call for SJ and we would be more like 1" in the 1" to 3" chances at this point.

The 12Z EURO run was much warmer than the 00Z Run. The 12Z GFS has trended colder with a more southern track to near Delmarvia. Also shows quick intensification near the coast and just offshore. This puts us in better QPF's and a colder solution.

To sum it up the latest GFS is 1" to 3" of mainly snow for SJ and the latest EURO run is rain with some snow and less QPF's. Which would leave SJ with maybe a coating. The Bad news is the EURO is usually correct and better model in this range.

Time to track and hope things look better with the model runs tomorrow.

Take Care,

Anonymous said...



The models are showing a rather moisture starved system for Tuesday (light snow or snow showers), but Very cold air with an Arctic front and a deep trough follow.(This system for Tuesday needs to be watched closely, as the models could be underplaying this potential as well).

Later in the week, I think we have a more impressive snow threat and a better system. The models are hinting on this, but IMO are too weak with the surface features vs the Upper level pattern. I'll keep an eye on it.