3/4/2008 FCST: GA/FL/SC/NC/VA

[Brian Stertz]

The setup looks very favorable for a potentially significant severe wx event to begin Tue. morning and continue into Tue. evening...with what looks to be a very strong LL and deep layer shear, strong kinematics, and decent instability on the forecast for Tuesday. It looks as though a severe squall line will transition eastward from S/E Alabama/W.Georgia/Florida Panhandle during the morning hours with what looks to be a primed and very sheared supercell environment from N.Florida into C/E Georgia, South Carolina, and possibly eventually into C/E North Carolina and S. Virginia as the upper system takes on the neg. tilt and the surface low deepens rapidly. Too early to call an outbreak here, but things do look pretty serious at this point. More tornadoes to add to the already very high 2008 tornado count IF the 00z GFS is close to a good forecast for this event.

 

[Chris Strahan]

upgrading to a Moderate risk today?



MESOSCALE DISCUSSION 0342
NWS STORM PREDICTION CENTER NORMAN OK
0533 AM CST TUE MAR 04 2008

AREAS AFFECTED...PORTIONS OF SC/NC INTO SOUTHEAST VA

CONCERNING...OUTLOOK UPGRADE

VALID 041133Z - 041300Z

A CATEGORICAL MODERATE RISK WILL BE ISSUED WITH THE FORTHCOMING DAY
1 CONVECTIVE OUTLOOK AT 13Z. A PUBLIC SEVERE WEATHER OUTLOOK WILL BE
ISSUED SHORTLY.

AHEAD OF A BROAD CONVECTIVE LINE ACROSS EASTERN TN AND EASTERN
AL/FAR WESTERN GA EARLY THIS MORNING...INCREASING BOUNDARY LAYER
MOISTURE /INTO THE LOWER 60S/ AND DAYTIME HEATING IS EXPECTED TO
CONTRIBUTE TO A WEAK TO MODERATELY UNSTABLE AIRMASS ACROSS THE
PIEDMONT/COASTAL AREAS OF NC/SC AND SOUTHEAST VA THIS AFTERNOON.
WITH THE APPROACH OF THE UPPER SYSTEM CURRENTLY ACROSS AR EARLY THIS
MORNING...INCREASINGLY STRONG FLOW FIELDS WITH ELONGATED LOW LEVEL
HODOGRAPHS WILL SEEMINGLY SUPPORT A RISK FOR A FEW STRONG
TORNADOES/POTENTIALLY WIDESPREAD DAMAGING WINDS ACROSS PORTIONS OF
SC/NC AND SOUTHEAST VA LATER THIS AFTERNOON INTO TONIGHT. FURTHER
DETAILS WILL BE AVAILABLE IN THE FORTHCOMING 13Z DAY 1 CONVECTIVE
OUTLOOK.



Expert forecasters.... care to weigh in?
I just don't see it happening as the heating is going to have a hard time going with cloud cover. Instability is an issue in my book too, but I am willing to hear all opinions on this!



Soooooo anyone in the area want to chase tonight? Not 100% sure I will go.... not sure I am 100% on board with the Mod risk, but if it holds and things look good, It could be a late night!

 

[Mike Johnston]

Chris, I'm catiously optimistic about the setup later today here in South Carolina. The wind fields at all levels look to be very impressive, with RUC showing the surface low gradually deepening through the day on a ENE track to WV, along with a favorable 500/850 mb profile.

I do agree that heating may be the most significant issue. At the current hour here in Charleston, we show 70t / 65td. A stratified cloud deck earlier this morning is giving way to some vertical development, and sun is peeking through now and again - visible satellite shows some partial clearing just south and west of here. On the other hand, the overnight convective band has pushed pretty far ahead of the front and is enroaching from eastern Georgia. We will need at least 3 hours of partial sun here to get temps up to the mid-70's. Moisture's not a problem, lapse rates should be decent later today, but we will need the heating to enhance instability. The Charleston AFD is talking about SB CAPE of 1,000 - 1,500 j/kg, but the RUC runs don't seem as supportive.

At any rate, I'll be spotting locally here if need be. I don't see much point in heading out to chase in the woods as I'm not sure any particular target in the risk area (during daylight, at least) is superior to my current location.

 

[Chris Strahan]

interesting that the spc has increased the size of the mod risk to include all of nc and sc

wonder what they are seeing .... I am in agreement with you there Mike. A big might.

I do think there will be some kind of spin up late late late and destroy some mobile home.. just seems to be the norm for here