USCAPEWEATHERAF

I am already sick of the events turning from snow to mix to rain. Had enough rain now. Everyone else in SNE is over at least 20", I am stuck as usual way behind at 1.2" of total snow. I know climatologically speaking I am not in a great place for snow until at least DEC 20th, so I should be grateful for 1.2" now, but I need my hunger fix.

weak precipitation right now, it is almost like sleet, but our surface temp is 31F.

Man it is accumulating quickly and temp dropped to 31F, with 1.75 mile visibility at the Chatham Municipal Airport.

I am snowing now, light snow, temp of 32F, dew point of 27F, calm wind. Pressure is at 1020mb.

Dew point depressions still high, around 12F, temp of 30F and dp of 18F. The precip will start over the Cape between 9z and 12z tomorrow.

Temp of 31F, dew point of 18, Temp/DP depression of 13F. Some dry air overhead.

We have a powerful shortwave in the southern stream, it is headed right for the area, and I know I will turn to rain. I really wish this winter does not follow this pattern and instead we get a real coastal snowstorm track pattern going in early to mid January.

12z CMC is a monster offshore, ocean storm with no impacts on the East Coast other than some waves. We need a faster phase between the streams.

It is the H7 and H85 lows that screw the area if we wanted all snow event, the centers cut across the region which is why the eastern areas torch to rain.

I have been watching that arctic shortwave try and bridge the southern stream and the northern stream for the Tuesday storm. However, most models have it as its own system, we need that arctic PV piece to dig more south into the OH Valley.

The models appear to be allowing that large piece of arctic shortwave energy to eject southeast from the main PV low over central Canada which is speeding up in the latest runs to the storm for Tuesday. In fact, I would suffice to say, that the arctic trough is allowing the progress of the Tuesday system to slow down more each run as it catches it and amplifies the flow over the Eastern Seaboard. This shortwave could eventually catch the system entirely and phase within the southern stream disturbance.

I personally have not liked the Tuesday storm from the start. I want that trailing polar/arctic shortwave energy to phase with the extra southern energy left behind the Tuesday system and allow for our own monster coastal storm to develop on Wednesday. It won't be a long duration event, there is no true blocking present even if transient. Problem is sometimes the models can't catch onto the intensity of the shortwave or speed of transit when it is less sampled.

OSU, that model has no idea what the hell it wants that energy to do next week. If we get a more amplified arctic jet, we will see some impacts from that potential coastal system. Southern energy is not pulled in or phased with the arctic shortwave and we get a near miss.

Simply, forecasting the weather is never perfect. In fact, the unpredictable nature of the weather is what fascinates those of us, who love the weather. The extremes, the puzzles that nature provides. What does allow a storm like Juno, NEMO, JONAS, or even Neptune form and impact us with such tremendous ferocity, I personally still put the Blizzard of 2005 ahead of JUNO, we received 35" of snow in my front yard from that storm. Now what I want to discuss with the viewers is simply the overall synoptic landscape of the weather patterns evolving next week. Right now the Saturday storm looks definite, and I would say we are at the 65% threshold that Cape Cod and SNE will receive a flooding rainstorm. The phase of cold air and the sub-tropical moisture connection is lacking and therefore not a cause for concern. The storm on Tuesday looks like at least a 55% probability for precipitation, question becomes, eventual track of the system. Now, there is a caveat next week that could change the outcome of the Tuesday storm, or become a storm on its own. A large piece of the Polar Vortex that moves south very slowly I might add, out of northern Canada and the Arctic Circle, which is why I know the arctic jet is present. The 12z NAM and GFS have slightly altering scenarios at 84 hours, and that is as far as the NAM goes, so any further is pointless. At 84 hours, the NAM is weaker and less amplified in the arctic jet over central/southern Canada. The GFS is actually more amplified, but the southern energy is too far ahead of the arctic shortwave to have much of a chance to phase. EURO is showing this energy as well, but the models are at odds at location and intensity of the shortwave and how it influences our phantom coastal around 100-120 hours out at this time. Still a lot of details to try and iron out which brings us to the biggest potential of the season to date around the first few days of Christmas week. Around the December 22-25th period, models have been hinting at a potential monster coastal nor'easter developing. The details and the impact that it will happen have yet to be determined. We have a lot of time left before that is even discussed more than at random at this time. So for the timeline I have written below, our certainty is this weekend, this late afternoon into Saturday, a major rainstorm, BUF could see a foot of snow. The further out in time, the more uncertain we are. Thanks for reading. 1.) Friday/Saturday December 13-14th, 2019 - rainstorm 2.) Monday evening/Tuesday morning December 16-17th, 2019 - mixed precipitation event, mainly rain for Cape Cod 3.) Wednesday potential coastal storm, not given yet, potential impacts snow and wind 4.) Following Monday into Wednesday December 23-25th, 2019 - Super Storm type nor'easter, potential for all impacts.

What that arctic shortwave energy that the models are starting to latch onto behind the Tuesday system. GFS has dug southeast the last two cycles.

It is still used

No I am not worried, I am staying home.

Kevin, it was rain for everywhere, the storm occluded all within the southern stream, with no phase or interaction with the northern stream, there was no cold air connection, which is what we need to keep the arctic high north of the area.

18z GFS looks like a monster rainstorm for Christmas week, no real phase in time with the northern stream and the high moves east.

The pieces that bring together the 12z GFS super bomb are on the CONUS around a week from today, the 19th of DEC. That is when the phantom southern stream energy makes its way into the RAOB fields of CA. The polar vortex lobe of energy is still in central Canada, so we don't know how strong that energy will be. Oh and the 18th system has a new wrinkle from the 18z GFS, the northern stream tries to dig in last minute.

The major timing in the models for the day 10-11 storm is when the PV is trying to split at hour 144, the ridging in the west and in the arctic tries to smash the PV low but it doesn't split and instead gets shoved into the Northeastern US. Just something to monitor the next 10 days. Oh and the EURO has no southern impulse of significance like John (TyphoonTip) said.

** Final Snow Observation: Location: Harwich, MA - 12:45 pm EST, snow ended. Snow total (2.20"), season total to this date: 3.40"

Hey Scott, there is some interesting bands developing to the southwest of the Vineyard, could be convective banding developing and the precip shield south of MVY and ACK seem to be pivoting from south to more northward then the front to the west. Interesting, maybe feeling the shortwave and a surface low is developing?

3-6" seems reasonable for the whole SE MA region.

That is awesome, bodes well for SE MA and the CC region.