Severe Weather Event...South

[jeff]

Significant outbreak of severe weather expected from E TX to GA over the weekend.

Today:

Severe thunderstorms will be possible by late afternoon along a surface front in C to NE TX. Parameters are favorable for supercells with main threats being large hail and damaging winds. Cap greatly increases southward so the seavere threat should be limited to C, N, and NE TX overnight.

Saturday:

Powerful trough begins to eject into TX with strong WAA over most of the Gulf coast. LLJ of 45-55kts will transport 60-65 degree dewpoints as far north as N MS. Impressive dynamics coupled with strong insolation will make for a very rough afternoon and evening from E TX to AL.

Clusters of dangerous supercells will develop within the warm sector. Shear profiles are favorable for all severe modes including long tracked tornadoes.

Air mass over E TX into LA will become very unstable by mid afternoon with high CAPE and high shear in place. Storms will develop along the advancing cold front from near Shreveport. LA to Conroe, TX and move eastward. These storms may form into a line producing widespread wind damage and hail damage. Supercells with a distinct tornado threat will continue to develop well ahead of this line over LA, MS, and AL.

This is a dangerous situation especially since it is a hoilday weekend and some may not be as aware as usual.

My next update will be early to mid afternoon

JL

[Brent]

SPC has a moderate risk out and says violent, long-track tornadoes are possible.

[Anonymous]

Yeah-what bad timing for a severe weather event on a holiday weekend-Is indeed possible if not likely to happen--hope people take heed to the warnings that are issued and stay safe!

[chadtm80]

[jeff]

Early afternoon Update.

TX:

Strong surface heating and continued weak WAA is increasing instability south of stalling cool front from N of KAUS to near KSHV. Air mass is becoming unstable from Temple to Lufkin N into the NW LA where cumulus field has developed. With continued heating and approach of an upper level disturbance thunderstorms should erupt by late afternoon over NC and NE TX along and ahead of the surface boundary. Deep layer shear, steep lapse rates, and CAPE of 1700-2200 J/kg will support supercells with splits. Main threat will be very large hail and high winds with tornadoes a lesser threat.

Thunderstorms will continue and increase after dark over N LA and AR as LLJ increases into the region and surface front moves back north due to lee of the Rockies pressure falls. Severe hail will be the main threats overnight.

Saturday:

Active severe weather day with potentail for a few high end events. Surface low pressure will form during the early afternoon due to upper level trough ejecting into W TX. Surface low should track from near KVCT to C LA into NW MS by early Sunday morning. Warm sector over SE TX, LA, MS, and AL will be very unstable by late afternoon with CAPES of 2000 +, low LI's, and strong deep layer shear. Capping will be strong over SE TX and S LA where it is questionable if the CINH can be broken. Further N and E over N LA, MS, and AL, clusters of supercells will develop with day time heating as low level WAA increases ahead of appraoching surface low. Shear profiles are favorable for supercells with large hail. Threat of tornadoes will be minimal early then increase greatly toward evening and overnight over LA, MS, and AL as low level shear increases and winds abck due to approaching surface low.

West:

Storms MAY develop by late afternoon near surface low over SE TX, however this threat is strongly related to cap intensity and moisture availablility. Air mass will be very unstable, but stout cap may keep convection from developing. As the surface low tracks into C LA during the evening hours, thunderstorms should develop along and ahead of the advancing front/ trough axis. Storms will go severe with large hail, high winds, and tornadoes. Supercells will continue to develop within WAA regime over MS, AL, and FL pand. during the night ahead of the surface low and likely squall line. Long tracked supercells with the potentail for a few violent tornadoes will be possible overnight Saturday into early Sunday. Greatest tornado risk appears to extend from SC LA across SC and C MS into S and C AL. This area is favored for nocturnal tornado outbreaks, and past events have resulted in numerous deaths and injures.

JL

[Wnghs2007]

What about Sunday...For areas like Alabama, Georgia, Tennessee, and the Carolinas? With that dry slot coming thru and the nam showing a possible for Severe thunderstorms what do you guys think?

[Brent]

What about Sunday...For areas like Alabama, Georgia, Tennessee, and the Carolinas? With that dry slot coming thru and the nam showing a possible for Severe thunderstorms what do you guys think?

I think supercells are a definite possibility. SPC has a huge slight risk out on Day 3.

[jeff]

What about Sunday...For areas like Alabama, Georgia, Tennessee, and the Carolinas? With that dry slot coming thru and the nam showing a possible for Severe thunderstorms what do you guys think?

I think supercells are a definite possibility. SPC has a huge slight risk out on Day 3.

I think the overall severe threat will continue into Sunday especailly over C/S GA, N FL and then late into the Carolinas. Overall tornado threat may be decreased, however hail and wind threat should continue with advancing MCS/ squall line. Highest tornado threat appears to be over N FL, into SC GA and extreme W SC. We are getting out to Day 3 so timing could have some impact as peak heating could gets things cooking further N, but I am not confident on where parameters will be located this far out along with convective delopments late Saturday.

[Brent]

My HWO:

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BIRMINGHAM AL
130 PM CST FRI MAR 25 2005

ALZ011>015-017>050-261330-
AUTAUGA-BARBOUR-BIBB-BLOUNT-BULLOCK-CALHOUN-CHAMBERS-CHEROKEE-
CHILTON-CLAY-CLEBURNE-COOSA-DALLAS-ELMORE-ETOWAH-FAYETTE-GREENE-HALE-
JEFFERSON-LAMAR-LEE-LOWNDES-MACON-MARENGO-MARION-MONTGOMERY-PERRY-
PICKENS-PIKE-RANDOLPH-RUSSELL-SHELBY-ST CLAIR-SUMTER-TALLADEGA-
TALLAPOOSA-TUSCALOOSA-WALKER-WINSTON-
130 PM CST FRI MAR 25 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE COUNTIES SERVED BY THE
NATIONAL WEATHER SERVICE OFFICE IN BIRMINGHAM.

.DAY ONE...(THIS AFTERNOON AND TONIGHT).

NO HAZARDOUS WEATHER IS EXPECTED.

.DAYS TWO THROUGH SEVEN...(SATURDAY THROUGH THURSDAY).

A VIGOROUS EARLY SPRING STORM SYSTEM WILL DEVELOP RAPIDLY TONIGHT
AND EARLY SATURDAY...MOVING EASTWARD ACROSS THE MISSISSIPPI RIVER
LATE SUNDAY. A WARM FRONT WILL LIFT NORTHWARD INTO THE TENNESSEE
RIVER VALLEY SATURDAY AFTERNOON PLACING CENTRAL ALABAMA IN THE
DANGEROUS WARM SECTOR OF THIS SYSTEM FOR 24 HOURS OR MORE. STRONG
TO SEVERE THUNDERSTORMS WILL MOVE ACROSS THE AREA LATE SATURDAY
AFTERNOON AND CONTINUE THROUGH THE MID MORNING HOURS ON SUNDAY.
DAMAGING WINDS...LARGE HAIL...AND TORNADOES WILL ALL BE
POSSIBLE IN ASSOCIATION WITH THESE STORMS. AT THIS TIME...THE
GREATEST THREAT FOR TORNADOES LOOKS TO BE LATE SATURDAY NIGHT INTO
EARLY SUNDAY MORNING. ANY OUTDOOR ACTIVITIES ON EASTER MORNING WILL
LIKELY BE THREATENED.

ON SUNDAY...PARTIAL CLEARING WILL RESULT IN DESTABILIZATION DURING
THE AFTERNOON HOURS. DRIER AIR FILTERING INTO THE REGION WILL
LIKELY RESULT IN ANOTHER ROUND OF STORMS...ALONG WITH AN INCREASED
WIND AND HAIL THREAT. STORMS ON SUNDAY AFTERNOON SHOULD BE OF THE
MORE ISOLATED VARIETY.

THE STORM PREDICTION CENTER HAS A MODERATE RISK FOR SEVERE WEATHER
FOR MOST OF CENTRAL ALABAMA ON SATURDAY THROUGH SATURDAY NIGHT...
AND A SLIGHT RISK ON SUNDAY.

STAY TUNED FOR FUTURE UPDATES...OUTLOOKS AND STATEMENTS REGARDING
THIS DEVELOPING SEVERE WEATHER EVENT.

.SPOTTER INFORMATION STATEMENT...

ACTIVATION OF STORM SPOTTERS AND EMERGENCY MANAGEMENT PERSONNEL IS
NOT EXPECTED THROUGH TONIGHT BUT WILL LIKELY BE NEEDED SATURDAY
AFTERNOON THROUGH EASTER SUNDAY.

[Skywatch_NC]

Chad, your post is blank...at least I don't see anything.

*UPDATE*

Okay, now I see it...don't know what happened earlier.

[jeff]

SPC MCD out of C TX. Visible images show Cu enhancement along and south of stalled frontal boundary in very warm air mass.

Isolated severe thunderstorms will develop in the next several hours as increasing moist and heating weaken a strong capping inversion.

Supercells with very large hail and damaging winds will be the main threats. Low level inflow is very weak, but should increase after dark allowing some storms to survive into NE and E TX. Thunderstorms should continue to increase through the night over N and NE TX ahead of lead S/W and on the nose of an intensifying LLJ.

[CYCLONE MIKE]

Jeff, what are your thoughts about when and how severe the weather could get tomorrow for the SE part of LA. The Baton Rouge/ New Orleans areas specifically? Thanks.

[PTrackerLA]

Jeff, what are your thoughts about when and how severe the weather could get tomorrow for the SE part of LA. The Baton Rouge/ New Orleans areas specifically? Thanks.

Add to that the Lafayette area. NWS is only giving us a 40% chance of rain, seems like most of the weather will stay north of here.

[jeff]

Complex of severe thunderstorms has developed this evening over C TX WNW of Austin along and just N of surface cold front which is starting to lift northward.

SPC has watchboxed a large part of C and N TX through the early morning hours.

Storms are elevated above the surface resulting in mainly a large hail threat although there was an earlier tornado warning. Shear profiles support storm organization through the overnight across C, N, and NE TX. Increasing LLJ late this evening will likely support additional development. Cap intensity greatly increase south of the current activity over SC and SE TX where SB convection would be possible, enhance most storms should stay along and N of the surface boundary.

Main threat will be very large hail and a few damaging winds gust.

[jeff]

Nasty supercell on south end of convective complex over C TX heading for metro Austin area.

Cells appear to the moving slightly right of the mean flow which is always a bit worrying. Cells are also feeding on very unstable air mass over SC and C TX with no convection to their south. Will be interesting to see how far ESE this cell will be able to make it. Its track likely determines the N edge of significant CINH.

[jeff]

Jeff, what are your thoughts about when and how severe the weather could get tomorrow for the SE part of LA. The Baton Rouge/ New Orleans areas specifically? Thanks.

I think the mod risk is a good bet for SE LA (New Orleans). This area should be closer to the better dynamics and track of the surface low. Areas across SC LA will have a large cap to overcome, although it probably will be broken by late afternoon or early evening. Overall coverage should increase from the coast inland as better dynamics and moisture will be found in those locations.

[jeff]

New WW posted for SE TX through 200am.

Complex of severe thunderstorms over C TX moving more ESE than expected into untapped instability.

I still have questions with regard to cap intendity, but it is clearly not as strong as indicated on the KCRP evening sounding.

Large hail and an isolated tornado threat is possible with the southern cell heading for KAUS.

[Shoshana]

We're seeing the lightning to our west.... (we're in Austin) no tornado watches or warnings, now it's Severe Thunderstorm Warning ... large hail, 70 mph winds.

Off to secure the stuff outside.

And shutting down the 'puter...

'shana

[jeff]

Interesting radar loop from C TX.

Frontal boundary clearly evident from C Travis County ENE to northern Lee County. W moving boundary over E Lee county. Fast northward moving boundary (maybe seabreeze) moving north just north of I-10. Boundaries appear to be on a collision course SE of Austin over the next few hours. Hard to say how the current complex just W of Austin will react to all this.

It should be noted that cap intensity increases toward SE TX and radar trends are showing an overall weakening trend.

We shall see how this all plays out

[Portastorm]

I'll tell you how its playing out in Travis County .... we just had a severe thunderstorm roll through north Austin with pea-sized hail at my house. Larger golf ball size hail further south towards downtown. Radar at 9:50 p.m. is showing a possible tornado in eastern Travis County moving east.

Fast moving storms but they pack a punch!