3/6 - 3/7 Event is it this seasons last gasp?

[superjames1992]

CMC is an oh hell no!  hahah

 

Looks colder than last run to me. (not that it still doesn't largely suck)

 

[deltadog03]

Ya. Y'all might still be ok. Why do I have a feeling the doc is gonna come in and prescribe cliff diving? Lol

[superjames1992]

Ya. Y'all might still be ok. Why do I have a feeling the doc is gonna come in and prescribe cliff diving? Lol

 

I don't know.  It can't possibly be any worse than the inland runner at 12z!

 

BTW, the GGEM argues for a changeover to snow for a period from just west of GSO down towards Gastonia with 850s dropping below 0C for a period.  Unfortunately, not much precip makes it into this area as the LP tracks well offshore.  Surface temperatures are in the low 30s.  Of course, a warm nose elsewhere would totally screw it, but it does look a little better than the 12z run in that regard.

[deltadog03]

Now batting, #1, the Doc!!

[superjames1992]

The western ridge is pumping up a little more early on.

[deltadog03]

prolly gonna look different this run vs 12z run.  Energy looks diff through hr 84

 

HR96 a lot different on how its handling energy not only for our storm, but also in NE.

[mackerel_sky]

Now batting, #1, the Doc!!

Going down like A-rod.

[superjames1992]

The storm looks faster this run... so far.  The HP is a little further NW, so it may slide out to sea slower, but further N isn't necessarily good, either.

 

The storm looks like it's going to be weaker this run, so I wouldn't expect the 993 mb beast in the Gulf that ran inland last run (recall that the 12z Euro sent the low through SW GA and into central SC).  This should give us an off-shore solution, at least.

 

We've got a 1008 mb LP just south of Mobile, AL at hr 114.  Looks a tad colder than last run.

 

Yep, a lot different... the low pressure is roughly west of Cedar Key, FL at hr 120... just a couple hundred miles off last run.  It's also 11 mb weaker.  Temperatures are colder so far.  I don't think it's going inland.

[superjames1992]

Looks like snow to ice for N NC.

 

Huge ice storm for GSO down towards CLT.  Well, 850s are 0C at GSO, so who knows... maybe it's snow.  Lots of precip.  WAY colder.  Surface temperatures are in the mid-20s!

 

Looks like GSO, INT remain below freezing for the duration, basically.  CLT makes it to 32.  Major winter storm.  RDU starts with ice, but changes over after a few hours.  Upstate SC gets some icing, as well.

[deltadog03]

This run is def. colder and looks better, but The ull is trending weaker, and CAD is slower/weaker to get in there.   Based on all that has been seen today, I really don't know about any CAD outside of WNC.  The ull is always a crapshoot, but more and more I feel like that is NOT going to produce.  Could be a thin narrow band that does with the deform.  T-3" over N and NE ga and up to 7 in the upstate and W and C do pretty well with this look... AGain, thats just the clown maps.  This solution ****honestly****** looks pretty good of what I think is going to happen.

[superjames1992]

The Euro clown shows 11-12" here.  I'll drink to that.

 

Yes, that's definitely overdone, but it's a big daddy event with a lot of precipitation.  I'd speculate a lot of sleet, though if temperatures were just a tad colder, it's predominantly a snowstorm.

 

5.6" for RDU and 6-7" or so for CLT.  Those might reflect the amount of liquid equivalent that falls as wintry precipitation, at least.  Maybe... if the clown has any use at all.

 

This run might imply ZR into a decent portion of NE GA.  Surface temperatures reach 33-34 in a lot of places and if the Euro is warm-biased at the surface in these situations, that could potentially be ice.

 

One thing to note is that precip doesn't even make it to Roanoke and the HP hangs on for awhile.  That's a massive change from last run with the low was slower, very strong, and ran inland and crushed DC, NYC, etc. with a rainstorm.  Of course, it's last run was way different than any prior run and I didn't really expect that to hold.

 

I'd say to take this run with a grain of salt for now... but if it holds at 12z we might have something.  I also thought the Canadian was a little better tonight.

[superjames1992]

Nice improvement tonight in the 00z Euro ENS mean.  The HP sticks around longer and the LP is quicker than the 12z mean.  Nice combination!  At hr 120, the HP is centered over New England while the low pressure is around Gainesville, FL.  The 12z Euro ENS mean had the HP off the coast of Maine by this time and the LP was further west around Panama City.  By hr 132, there is what appears to be a decent consensus for a low pressure centered approximately 150 miles to the ESE of Myrtle Beach and by hr 144, it is approximately 150 miles east of Cape Hatteras.

 

850s are considerably colder than the last run, as well.  NW NC is cold enough to start out as snow on the means.  I'm not a huge fan of trying to use means to determine SN lines, though, as a few members can severely skew the mean one way or another (a massively amplified ensemble member that warms an area's 850 mb temperature up to 10C would have a large effect, for example).  The shift from last run is positive and that's the main thing.

[KChuck]

Interesting post from NWS RAH this morning covering tomorrow's time period. See http://mobile.weather.gov/index.php?lat=36.13&lon=-80.08#forecaster_reasoning .

WINTER STORM WATCH ISSUED FOR THE NORTHERN NC PIEDMONT - INCLUDING

PERSON...GRANVILLE...VANCE...AND WARREN COUNTIES - FOR MON AND

MON NIGHT.

...TEMPERATURES WILL DROP AS MUCH COLDER AIR SURGES IN BEHIND THE FRONT... WHICH

WILL CROSS THE AREA IN BACKDOOR FASHION FROM NORTH TO SOUTH. A 40-50KT SOUTHWESTERLY LLJ WILL FEED MOISTURE OVER THIS SHALLOW SURFACE LAYER... AND THE RESULTING WARM NOSE IS INDICATED WITH AN IMPRESSIVE INVERSION ON MODEL FORECAST SOUNDINGS. AS TEMPERATURES DIP BELOW

FREEZING... THIS WILL SET THE STAGE FOR A CHANGE OVER TO A POTENTIALLY BRIEF PERIOD OF FREEZING RAIN... FOLLOWED BY SEVERAL

HOURS OF SLEET DURING THE AFTERNOON.

Then for Thurs nite...

ATTENTION WILL THEN TURN TO A WAVE THAT NWP GUIDANCE HAS INDICATED

WILL LIFT OUT OF THE GULF OF MEXICO AND UP THE SOUTHEAST COAST MID-

LATE WEEK. THE OPERATIONAL EC AND EC ENSEMBLE MEAN STILL FAVOR THE

DEVELOPMENT OF A CLOSED MID LEVEL LOW IN THE SOUTHERN STREAM AND

RESULTANT SLOWER SURFACE CYCLONE PROGRESSION UP THE SOUTHEAST COAST...WHILE THE GFS AND ASSOCIATED ENSEMBLE MEAN INDICATE LESS STREAM SEPARATION AND A MORE PROGRESSIVE SYSTEM. DESPITE THIS MODEL SPREAD AND ASSOCIATED FORECAST UNCERTAINTY...THE FAVORED TIMING FOR PRECIPITATION IN CENTRAL NC REMAINS IN THE LATE THU-EARLY FRI TIME FRAME...AND THROUGHOUT FRI IF THE SLOWER EC SOLUTIONS VERIFY.

GIVEN THE FAVORED MILLER "A" PATTERN OF CYCLOGENESIS...WITH STRONG CLASSICAL CAD - PARTICULARLY EARLY IN THE EVENT - THERE SHOULD BE A NARROW TRANSITION ZONE FROM RAIN TO WET SNOW...WITH THE LATTER...OR

AT LEAST A MIX...FAVORED OVER THE CLIMATOLOGICALLY-FAVORED WESTERN PIEDMONT BEFORE THE PARENT HIGH WEAKENS/RETREATS BY FRI. THIS VERY MOISTURE-LADEN SYSTEM DEFINITELY BEARS WATCHING.

BUFR FORECAST SOUNDINGS AND SREF PLUME DIAGRAMS SUGGEST THAT FIFTEEN HUNDREDTHS TO PERHAPS AS MUCH AS ONE QUARTER INCH OF THE LIQUID EQUIVALENT PRECIPITATION WILL FALL AS SLEET. WHEN FACTORING

IN AN ASSOCIATED SLEET WATER EQUIVALENT OF 4:1...SLEET ACCUMULATIONS OF ONE HALF INCH OR GREATER ARE LIKELY NEAR THE VA

BORDER...WHICH NECESSITATES THE ISSUANCE OF A WINTER STORM WATCH FOR THESE AREAS. THIS TRANSITION TO SLEET WILL TAKE PLACE RAPIDLY AS THE COLD AIR SURGES SOUTHWARD. SOME SNOW MAY MIX IN DURING THE EVENING HOURS AS THE WARM NOSE DROPS TO NEAR FREEZING...BUT THIS POTENTIAL IS SHORT-LIVED AS MIDLEVEL DRYING OVERTAKES THE AREA. A WINTER WEATHER ADVISORY WILL LIKELY BE NEEDED FOR LARGER PORTION...IF NOT ALL OF CENTRAL NC...AS WE MOVE WITHIN 24 HOURS OF THIS EVENT.

[wncweather]

I am looking for rain starting out then transitioning over to some sleet and freezing rain in my area and maybe some snow before it's all said in done.  I do however think the freezing rain will be the biggest concern for the foothills right now.

[BullCityWx]

Looks like a ton of sleet here.

[Mark Dee]

Given the ice / snow threat up north, with this Gulf of Mex extratropical low, equally in concern, the severe wx convective risk to mariners over the eastern Gulf and west coast of Florida may be significant on Thursday, then crossing the state thereafter.

 

 

DAY 4-8 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0323 AM CST SUN MAR 02 2014

VALID 051200Z - 101200Z

...DISCUSSION...
...FLORIDA PENINSULA AND KEYS -- D5/THU...
THE CONSENSUS AMONGST THE LATEST GLOBAL MODEL GUIDANCE AND RELATED
ENSEMBLE SOLUTIONS CONTINUES TO BOLSTER CONFIDENCE THAT SEVERE
THUNDERSTORMS COULD BE POSSIBLE FOR THE FLORIDA PENINSULA AND KEYS.
PRESENT INDICATIONS ARE THAT THIS POTENTIAL WOULD BE MAXIMIZED ON
D5/THU. THIS WILL OCCUR AS THE BASE OF A SHORTWAVE TROUGH DIGGING
OVER THE PLAINS EVENTUALLY OVERLIES AMPLE LOW-LEVEL BAROCLINICITY
OVER THE GULF OF MEXICO...BREEDING STRONG CYCLOGENESIS OVER THE GULF
FOR THE MIDDLE OF THIS WEEK. THE DEEP MERIDIONAL FLOW COMPONENT
WITHIN THE ENSUING WARM SECTOR WILL TRANSPORT ABUNDANT TROPOSPHERIC
MOISTURE/HIGH BOUNDARY-LAYER THETA-E POLEWARD.

STRONG UNIDIRECTIONAL WIND PROFILES WITHIN THE WARM SECTOR MAY
FOSTER ONE OR MULTIPLE SQUALL LINES CROSSING THE PENINSULA AND
KEYS...WITH DAMAGING WINDS AND PERHAPS A FEW TORNADOES OF CONCERN.
WHILE BUOYANCY WILL LIKELY BE LIMITED BY ONLY MODEST MID-LEVEL LAPSE
RATES...THE OVERLAP OF A WARM/MOIST BOUNDARY LAYER WITH STRONG
LOW-LEVEL/DEEP SPEED SHEAR COULD ENHANCE THE SVR POTENTIAL. THIS
WOULD ESPECIALLY BY THE CASE IF A STRONG MID-LEVEL DRY INTRUSION
COILS AROUND THE SRN SEMICIRCLE OF THE PARENT DEEP EXTRATROPICAL
CYCLONE ENHANCING POTENTIAL INSTABILITY...AS SOME MODEL SOLUTIONS
INDICATE.

HOWEVER...THE DELINEATION OF ANY AOA-30-PERCENT SVR THUNDERSTORM
PROBABILITIES HAS BEEN WITHHELD AT THIS TIME OWING TO STILL-ONGOING
DIFFERENCES AMONGST VARIOUS MODEL SOLUTIONS REGARDING THE DETAILS OF
THE CYCLOGENESIS PROCESS AND THE RELATED EVOLUTION OF BUOYANCY AND
WIND FIELDS. SHOULD MODELS CONTINUE TO CONVERGE ON A SOLUTION
SUPPORTING AN ENHANCED SVR THREAT...PROBABILITIES MAY BE NEEDED IN
SUBSEQUENT OUTLOOKS.

..COHEN.. 03/02/2014

[burrel2]

I know it’s the 84 hour NAM, but I like the looks of it.  The key piece to watch, imo, is that northern piece in SE Canada/Northeast US.  The GFS has that piece retrograding back west and merging with the piece over central Canada. That causes our parent high to weaken.  If we can get that piece to generate a surface low off the northeast coast, it will help lock in a stronger high pressure for CAD.  The NAM appears to be doing just that.  

 

The euro is unlike the GFS in that it keeps that piece moving east, and thus sets up excellent confluence for a CAD high pressure, but it doesn’t generate much of a cyclone from it and consequently our high pressure starts to slide off the coast later in the event.  

[burrel2]

Here you can see where the GFS is merging those two pieces in Canada and thus messes up the confluence in the Northeast.  

 

Note: The GFS is the only model doing this; that I am aware of.

[mackerel_sky]

I know it’s the 84 hour NAM, but I like the looks of it. The key piece to watch, imo, is that northern piece in SE Canada/Northeast US. The GFS has that piece retrograding back west and merging with the piece over central Canada. That causes our parent high to weaken. If we can get that piece to generate a surface low off the northeast coast, it will help lock in a stronger high pressure for CAD. The NAM appears to be doing just that.

The euro is unlike the GFS in that it keeps that piece moving east, and thus sets up excellent confluence for a CAD high pressure, but it doesn’t generate much of a cyclone from it and consequently our high pressure starts to slide off the coast later in the event.

So the low off of Maine will not let the high slide east as quickly?

[burrel2]

Here you can see the Euro keeps that piece of energy moving east, but it is so dampened out that it doesn’t generate much of a low pressure out in the Atlantic; consequently, our high pressure starts to slide off the coast sooner than we would like.  

 

Edit: I added the wrong image on the first try; it has since been changed

[burrel2]

So the low off of Maine will not let the high slide east as quickly?

 

That is my assumption.  I’ll add that all of my comments should be taken with a grain of salt; as I’m just a model watching weenie.  Maybe some other people can chime in their thoughts on my assumption?

[Tacoma]

Here you can see where the GFS is merging those two pieces in Canada and thus messes up the confluence in the Northeast.  

 

Note: The GFS is the only model doing this; that I am aware of.

GSP says they are not going with the GFS.  they to said something to this effect but its an outlier that the trends have been favoring the euro for the possible snowstorm at the end of next week.  gsp is leaning toward a winter storm next week 6-7 in they're lingo. from I85 north though confidence is low right now.

[burgertime]

The GFS is bringing that low over the lakes which is killing any real chance of cold air. We badly need a solution like the 84 NAM had.

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[deltadog03]

GFS isn't going to work in CAD areas...the high is weaker and way out of potion and the low coming through the lakes screws that up.

[burgertime]

GFS isn't going to work in CAD areas...the high is weaker and way out of potion and the low coming through the lakes screws that up.

Gotta hope the good doc comes in with a better solution or our coach may turn into a pumpkin at midnight. I said it before but I really don't think anyone does well in the SE on this one without an ULL.

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[Tacoma]

GSP is calling the storm next week a classic Miller A, so if we can get the cold air close by, but with all the snow pack to the north of the carolinas it won't take much to drag the cold air down into the storm plus maybe the storm itself will produce its own cold air to a certain degree.   MAYBE  

[mackerel_sky]

GFS isn't going to work in CAD areas...the high is weaker and way out of potion and the low coming through the lakes screws that up.

Still 4 days out, and that low has appeared and disappeared every couple of runs, and it's the GFS. Gives me a little hope that GSP is not going with GFS, and Euro coming back to a colder solution last night was a plus! Today's 00z Euro will be interesting to see.

[Brick Tamland]

Wow, what a difference the Euro was last night. Looks like central NC can have a couple of chancces for fun this week.

[deltadog03]

Gotta hope the good doc comes in with a better solution or our coach may turn into a pumpkin at midnight. I said it before but I really don't think anyone does well in the SE on this one without an ULL.

Sent from my HTC One

I am beginning to agree with you for sure.  The ULL has even been trending *hittier every consecutive euro run as well.  I think the CAD areas of N and W NC could do ok with some CAD stuff with the initial, but the ULL may not do anything but be pretty and give some rain for *Most areas.

[Tacoma]

guys it doesn't take much for a wet snowfall.  i've seen it happen at 34/35 degrees quite a few times when the mtns. received a foot of snow.  then again all the conditions have to be just right.  Maybe next week we can get this scenario.