Jump to content
  • Member Statistics

    17,608
    Total Members
    7,904
    Most Online
    Vesuvius
    Newest Member
    Vesuvius
    Joined

Feb 25-26 Discussion/pbp


Wow

Recommended Posts

A great ouuput in WNC. The NAM continues to love the SW NC mountains, Nothern Upstate and southern foothills with heavy rates of snow..

 

This is a lot better run for the northern foothills/mountains and NW Piedmont, too.  The 18z NAM was kind of scant there (0.25-0.5" QPF).  Now, GSO is on the cusp of 0.75" QPF, which is solid, and the entire area is 0.50-0.75".

 

CR, I hear you about cutting back on totals, but with this setup, it doesn't seem that far out of the question to see this kind of QPF (maybe it's overdone in that band from RDU northward, though compaction and ratios would mean that's not going to add up 10:1 as snow, anyways).

Link to comment
Share on other sites

  • Replies 3.8k
  • Created
  • Last Reply

WPC, having the heaviest snowfall forecasts so far, has been tossing the NAM FWIW...good weenie runs but I wonder when it will start to back off the precip if it does?

 

Disco from 4pm:

"THIS SHOULD RESULT IN A POTENTIALLY DECENT DYNAMIC COOLING REGIME FROM NRN GA/ERN TN THROUGH NC/SRN VA AND PERHAPS FARTHER NORTH. THIS ENTIRE FCST SOUND FAIRLY STRAIGHT FORWARD... HOWEVER A DECENT AMOUNT OF SPREAD EXISTS WITH THE GUIDANCE. THE CLEAR TREND OVER THE PAST 24 HRS IS A CONTINUE TREND TO THE NORTH WITH THE EXTENSION OF THE DEVELOPING PRECIP SHIELD. THE 12Z NAM/09Z SREF MEAN ARE AN ACTUAL CLEAR OVER-AMPLIFIED SOLUTION... WHILE THE GFS/ECMWF ARE MORE SUBDUED. WPC BOUGHT THE NORTHWARD TREND BUT REMAINED CONSERVATIVE IN RELYING CLOSE TO THE GLOBAL DUO OF THE GFS/ECMWF THROUGHOUT. THIS MEANS DRAWING SNOW FARTHER NORTH INTO PARTS OF THE TN VALLEY/APPALACHIANS AND MID-ATL REGION. THIS FCST REMAINS FLUID ESPECIALLY THURS FOR A REGION SUSCEPTIBLE TO ANY WINTER WEATHER INVOLVING AN ACTIVE SRN STREAM... PLENTY OF MOISTURE AND ARCTIC AIR."

Very reasonable.

Now we wait for the GFS to come in and say warm and dry.

Link to comment
Share on other sites

No doubt James! Also, heavy rates should limt any rain at the onset...

 

This is a lot better run for the northern foothills/mountains and NW Piedmont, too.  The 18z NAM was kind of scant there (0.25-0.5" QPF).  No, GSO is on the cusp of 0.75" QPF, which is solid, and the entire area is 0.50-0.75"/

 

Once again the NAM drops over 1.25 here. It would be nice if the others agreed!

Link to comment
Share on other sites

Regarding whether or not KATL is mainly rain, does anyone recall the great 3/24/1983 snow? KATL got the heaviest snow since 1940. From what I was told by someone in Cobb county, nobody expected it to be snow. It turned out to be a mainly very wet snow with huge flakes. I wasn't in ATL to experience it. Could this end up similar? Opinions?

I was a senior in high school here in upstate South Carolina when that storm occurred.  One of the things I remember is that it occurred on a Friday and like today's event, we had a little teaser on the Wednesday before.  Not saying this event is even close to that one but an interesting coincidence.  Huge flakes, got over 10" here while just down the road in Anderson, not a flake.

Link to comment
Share on other sites

Wow! What a run! For once I'm sitting pretty. Nam kills north georgia! I'm nervous though! Great run for Cumming north.

I woud like my chances where you are, the NAM is likely still too far north by a bit, its now maybe within 30 miles of the RGEM on NGA snow totals, if the RGEM comes south this gets interesting for N ATL

Link to comment
Share on other sites

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE PEACHTREE CITY GA

909 PM EST TUE FEB 24 2015

.UPDATE...

BASED ON THE 18Z RUN OF NAM/GFS...HAVE MADE ADJUSTMENTS TO THE

TEMPERATURE TREND FOR WEDNESDAY WITH HIGHS TEMPS COMING IN THE

MORNING ACROSS NORTH GA...THEN WITH THE ONSET OF PRECIP...LOWERING

TEMPS. THIS WILL ALSO AFFECT PTYPE. WITH THE COLDER TEMPS...BASED

ON TEMPS WET BULBING DURING THE AFTERNOON WITH THE PRECIP...HAVE

MADE THE TRANSITION OF RAIN/SNOW MIX TO ALL SNOW BY MID AFTERNOON

MOST AREAS IN THE WARNING. THE SOUTHERN TIER OF THE WARNING WILL

STILL HAVE MOSTLY A RAIN/SNOW MIX UNTIL LATE AFTERNOON WHERE IT

WILL TRANSITION OVER TO ALL SNOW.

Link to comment
Share on other sites

That future cast run is troubling..  a shift NW by about 50 miles and most of Wake gets blanked.

It's not going to shift NW by that much. What happened is their crappy model shifted to what all the other models have been saying all day. We have not had a significant north shift today, if anything, it's been a little bit south at times and weaker, but not much.
Link to comment
Share on other sites

Everybody is all giddy about the RAH area on that run, but NGa looks to do amazingly well. Wondering about the sudden cut off into SC and then the strip around RAH!? Is there a transfer or something? Just can't see how it stops like that in GA

You've got overrunning and then the coastal takes over. There will be a precip min somewhere. Robert's map shows that. Impossible to say exactly where, but it'll happen.

James, I hear what you're saying but I want to see other guidance come in with 1+" amounts. Until there's a consensus there, I think the NAM is too high, as usual. Still, it's a nice hit!

Link to comment
Share on other sites

I woud like my chances where you are, the NAM is likely still too far north by a bit, its now maybe within 30 miles of the RGEM on NGA snow totals, if the RGEM comes south this gets interesting for N ATL

it's a touch colder than the 18z run but I still can't help but think the nam is too warm aloft and indeed heavy precip will keep temps from warming aloft as much as it keeps insisting. this run actually drops 850s below 0 initially then by around hour 23 moves them just above 0 again. What is worrisome to me about this is that it does right in the middle of very intense precip rates. In fact the nam is actually showing a little dynamical cooling taking place way to the south over south georgia/southern sc with the blob of heaviest convection.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...