Palmetto Proving Grounds

Talkweather.com is an awesome form to follow...

The further south the low goes, the better chance for snow everywhere north of it. Low pressure sucks in colder air from the north, so if the low goes north we get rain, if it goes south we get snow, if it slows down and goes offshore right about the GA/SC line, we get lots of snow.

As soon as the nws starts mentioning snow rhe models shift the l to far south. Curious to see if this nam run is going to send it to miami.

SHORT TERM /THURSDAY THROUGH SATURDAY NIGHT/…
AS OF 315 AM WEDNESDAY…SOME COMPELLING CHANGES IN MODEL GUIDANCE
POINT TO AN EVENT OF HISTORIC PROPORTIONS OVER THE PIEDMONT OF THE
CAROLINAS FOR CHRISTMAS DAY. THE ECMWF HAS BEEN REMARKABLY
CONSISTENT FOR THE PAST THREE DAYS WITH A SOUTHERN TRACK OF A
DEVELOPING LOW ACROSS THE DEEP SOUTH/NRN GULF COAST ON SATURDAY AND
SATURDAY NIGHT. THE GEM GLOBAL HAS MORE OR LESS BEEN FOLLOWING THAT
LEAD. FINALLY…ON THIS MODEL CYCLE…THE GFS…WHICH HAS BEEN A
FASTER NORTHERN HOLDOUT…IS ON BOARD WITH MOVING THE MAIN LOW
PRESSURE CENTER SLOWLY ALONG THE NORTHERN GULFMEX COAST ON CHRISTMAS
DAY. ON THE ONE HAND…THIS HAS RAISED CONFIDENCE THAT OUR MOSTLY
WHITE FORECAST FOR THE WEEKEND IS ON THE RIGHT TRACK. ON THE OTHER
HAND…CONFIDENCE IN THE GFS IS WEAKENED WITH ITS MAJOR DEPARTURE.
CONFIDENCE WILL GROW FURTHER IF THE OPERATIONAL GFS KEEPS WITH THE
SLOWER SOLUTIONS OF THE ECMWF AND GEM. NO MATTER WHICH MODEL HAS THE
BETTER TRACK…ALL THE MODELS NOW FEATURE PARTIAL THICKNESS VALUES
THAT FAVOR ALL SNOW OVER THE MAJORITY OF THE FORECAST AREA. FORECAST
SOUNDINGS LACK A WARM NOSE…SO IT LOOKS LIKE A RAIN/SNOW PROBLEM.
THE ONLY LOCATIONS THAT WOULD MIX OR CHANGEOVER TO RAIN WOULD BE
ROUGHLY SOUTH OF A LINE FROM HARTWELL TO ANDERSON AND LAURENS. TEMPS
SHOULD BE WELL BELOW THE GUIDANCE WITH THIS SCENARIO. WITH MUCH OF
THE PRECIP TYPE ISSUES OUT OF THE WAY…THE FORECAST BECOMES MORE OF
A TIMING AND QPF PROBLEM…THE GFS STILL BEING 6-12 HOURS FASTER
WITH ONSET BETWEEN MIDNIGHT AND SUNRISE CHRISTMAS DAY. THE SLOWER
ECMWF WOULD HAVE ONSET AFTER SUNRISE TO NOON SATURDAY. WITH THE GFS
ON BOARD…THE FORECAST IS BLEND OF THE GFS AND ECMWF FOR TIMING.
POP RAMPS UP FROM CHANCE TO LIKELY MAINLY SATURDAY MORNING AND
AFTERNOON. IN AN EFFORT TO REIN IN THE EXCITEMENT…THE QPF
GENERALLY FOLLOWS THE LOWER AMOUNTS ON THE GFS…WHICH STILL GIVES
US A UNIFORM 3-5 INCHES OF SNOW ACROSS THE FORECAST AREA SATURDAY
AND SATURDAY NIGHT…WITH THE EXCEPTION OF ELBERT…ABBEVILLE…AND
GREENWOOD COUNTIES THAT STAY ON THE WARM SIDE OF THE RAIN-SNOW LINE.
IT SHOULD BE NOTED THAT THE SLOWER AND STRONGER ECMWF HAS PLENTY OF
SUPPORT FOR ITS SOLUTION. IF THAT MODEL WERE TO VERIFY…WE WOULD
HAVE A MAJOR WINTER STORM MOVING UP THE COAST OF THE CAROLINAS
SATURDAY NIGHT AND SUNDAY…AND THE PIEDMONT WOULD STAND TO GET UP
TO DOUBLE WHAT IS CURRENTLY FORECAST. EITHER WAY…IF WE CONSIDER A
WHITE CHRISTMAS TO BE ONE INCH ACCUMULATION ON CHRISTMAS DAY…THAT
HAS NOT HAPPENED IN THE AREA FROM GREENVILLE (1963) TO CHARLOTTE
(1947) IN NEARLY 50 TO 60 YEARS. IF THIS FORECAST WORKS OUT…IT
COULD BE AN EVENT THAT WILL BE TALKED ABOUT FOR THE REST OF OUR
LIVES. THE POTENTIAL DOWNFALL WOULD BE IF THE SYSTEM SLOWS DOWN EVEN
MORE…IN WHICH CASE THE BULK OF THE SNOW WOULD FALL ON SUNDAY. STAY
TUNED!

Better for it to be modelling too south than modelling too north at this point.

Yeah, that is about a foot of snow from Orangeburg north, hahahhaa.

Flurries would make a white Christmas as far as I'm concerned. You take what mother nature will give you in SC. That being said COME ON SNOW!!!!

Raleigh Weather Examiner

I would think that Northern Gville co and western NC would have the best bets for SIGNIFICANT snowfall, correct?

Man I hope we get some snow.

Not necessarily. Greenville and upstate SC are funky. Pretty much bet on the NC mts getting some snow, but the largest amounts could easily be in the eastern NC piedmont, East of I-77, along I-40 Raleigh/G-boro, etc. That frequently happens. The Raleigh area and eastern NC get a good deal more snow than upstate SC, despite the fact that upstate SC is at a higher altitude, closer to the mts and frequently cooler.

If the Low passes through GA, midlands of SC and offshore around Charleston, upstate gets hammered.

CA Wave Initializes Today
Alex brought up a critical point this morning when she mentions that the upper-level enegy responsible for our Christmas storm (a large part of it) moves over an area of much beteer diagnostics later today. Upon inspection of the NAM and GFS over the last 3 runs, they have all kept that energy weaker than what is actually going on with it as it reaches the coast. This tells me the actual progress of the storm energy will be somewhat slower than the NAM & GFS (GFS notoriously not as good with southern stream, Pacific energy).

It’s a good model in a one-flow pattern… but, this split flow is making the GFS jump around and we have all seen that with it’s track as it has gone from a TN/KY track to a Cuban Missile diver in 3 days! There is literally zero reason right now to trust the GFS. It’s flip flopping around like nobody’s business and that’s a sure sign it’s having problems initializing the Pacific Wave coming into California today. As much as a lot of people would love for the much strong Euro to be right though, it’s hard to jump on the most extreme solution… and not justified at this point. But, the consistency of the Euro is very hard to ignore. HPC, NWS and some very accurate meteorologists are trusting it right now, so I see no reason to think the GFS and NAM are still playing catch-up, but asthis Pacific energy makes it onto shore today, I think we will start having a much better idea what solution has the best chance of playing out over the next 24-hours. Snow, or no snow, HPC pointed out the other day that the European forecast model has an high verification rate at initializing Pacific-stream energy.

Again, proceed with caution is the best route to take since we are dealing with the critical timing or two jetstreams of energy. That timing may or may not work out for us, but we should know one way or the other pretty soon.

Andy Wood