Severe Wx Threat Mid Week

[sparky]

OK have noticed that several wx offices to my west including BMX is mentioning the threat of strong/severe wx in the wednesday/thursday time frame. I have read that 500mb winds could reach 100kts. at 500mb. Jeff what is your take on this event? I see a straight line wind threat but if i am right we may have a tornado threat as well depending on the ammount of instability and time of day it passes.

[jeffl]

Decent severe weather event setting up for mid to late week.

Strong upper air forcing along with a powerful disturbance will create very favorable conditions for severe weather from EC TX Wednesday to AL on Thursday. A 60kt low level jet below a 120kt mid level jet will create much energy within the air column. Capping will be a problem along the coast with better profiles inland. Instability may also be lacking. The main question in GA will be how much the SE US ridge gives. There may be enough ridging still in the SE US to cause the storms to weaken as they move into GA.

Given the wind energy a long lived damaging squall line appears the most likely with the possibility of rotating supercells ahead of the main line over N LA, N MS, and N AL. CAPE may be limited to the 1500J/KG range, but the impressive dynamics should overcome the limited instability. Helicity values near 300m^2/S^2 could produce a few strong tornadoes.

I have serious question over GA, as I think the ridge will maintain enough influence to weaken the line as it moves east and the best upper support shifts toward the Great Lakes.

[michaelwmoss]

That might make it more likely for my area:




548
ACUS02 KWNS 110652
SWODY2
SPC AC 110651

DAY 2 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1251 AM CST TUE JAN 11 2005

VALID 121200Z - 131200Z

THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 25 SW
GLS 45 NE CLL 45 ENE DAL 40 SSW TUL 25 NW CNU 20 ESE STJ 35 ENE LWD
OTM 20 NNW BRL 35 SW PIA 10 SSW MVN 35 NNE MKL 30 WSW CBM 40 E MCB
40 SW HUM.

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE LOWER AND
MID MS VALLEY...

AN UPPER-LOW CURRENTLY LOCATED NEAR THE COAST OF NRN CA WILL OPEN
AND ACCELERATE QUICKLY ESEWD ACROSS THE ROCKIES AND INTO THE PLAINS
BY THE DAY 2 PERIOD. MOISTURE ADVECTION WILL INCREASE AHEAD OF THE
APPROACHING SYSTEM AS A STRONG LOW-LEVEL JET DEVELOPS ACROSS NORTH
TX AND OK EARLY IN THE PERIOD. A PACIFIC FRONT WILL ORGANIZE AND
MOVE EWD INTO THE SRN PLAINS LIKELY REACHING ECNTRL OK AND ECNTRL TX
DURING THE AFTERNOON. A BAND OF FOCUSED ASCENT AHEAD OF THE UPPER
TROUGH COMBINED WITH SFC HEATING SHOULD PROVIDE INSTABILITY AND LIFT
FOR RAPID STORM DEVELOPMENT ALONG AND AHEAD OF THE FRONT DURING THE
LATE AFTERNOON ACROSS MO...SE KS AND NRN AR. THE STORMS SHOULD
QUICKLY EXPAND SWD ACROSS ERN OK...NE TX AND LA DURING THE EVENING
HOURS AS THE BAND OF ASCENT OVERTAKES THE FRONT CAUSING SQUALL-LINE
DEVELOPMENT.

FORECAST SOUNDINGS FOR 00Z THU ACROSS WRN AR SHOW ABOUT 70 KT OF 0-6
KM SHEAR WITH ABOUT 1000 J/KG OF MLCAPE. THIS SHOULD BE SUFFICIENT
FOR SCATTERED SEVERE STORMS. A PLUME OF STEEP MID-LEVEL LAPSE RATES
ASSOCIATED WITH THE UPPER-TROUGH WILL PUNCH QUICKLY NEWD ACROSS OK
INTO SE KS...SW MO AND WRN AR BY THE EARLY EVENING. STORMS THAT
FORM NEAR THE EDGE OF THIS PLUME ALONG THE WEST EDGE OF THE HIGHER
INSTABILITY WILL HAVE A POTENTIAL FOR LARGE HAIL. DUE TO STEEP
LOW-LEVEL LAPSE RATES AND STRONG LOW-LEVEL SPEED SHEAR...WIND DAMAGE
WILL ALSO BE POSSIBLE AS STORMS INITIATE ACROSS SE KS...NE OK...MO
AND AR. THE WIND DAMAGE THREAT SHOULD CONTINUE AND EXPAND SWD ACROSS
NE TX...SE OK AND LA AS THE SQUALL-LINE ORGANIZES DURING THE
EVENING. A TORNADO THREAT WILL ALSO EXIST WITH ROTATING CELLS UPON
INITIATION AND WITH EMBEDDED SUPERCELLS AS THE SQUALL-LINE
ORGANIZES. THE SEVERE WEATHER THREAT SHOULD CONTINUE EWD REACHING
WRN IL...WRN TN AND WRN MS BY LATE IN THE PERIOD.

..BROYLES.. 01/11/2005

What do you all think? Hail and wind mostly? Maybe some Tornadoes when the storms first start developing?

[michaelwmoss]

Indeed it is. I will be broadcasting soon overnight about the current severe weather. You can catch the stream at:

http://radio24.nhcwx.com:8024/listen.pls

[michaelwmoss]

Will be streaming again here shortly due to Tornado Warnings In The SouthEast

http://radio24.nhcwx.com:8024/listen.pls

[ticka1]

We had thunderstorms roll through around 1:30 a.m. - rained close to an inch - woke me up LOL...good line of storms came through with winds - oh was the wind blowing.

[BaytownWeatherWatcher]

We had thunderstorms roll through around 1:30 a.m. - rained close to an inch - woke me up LOL...good line of storms came through with winds - oh was the wind blowing.

I didn't hear a thing. I slept through it all.

[ticka1]

Lucky you BWW - wish I could of slept through it. The thunder and lightning woke me up LOL......

[BaytownWeatherWatcher]

Lucky you BWW - wish I could of slept through it. The thunder and lightning woke me up LOL......

Usually I wake up when a storm comes through...I must have been very tired!

[sparky]

got A LOT rain here and we had some wicked looking clouds around 5:30 yesterday evening evidently whatever was over us built up and formed a stronger squal line that hit and spawned some toranadoes. One in particular, hit Laurens South Carolina which is roughly about an hour and fifteen minutes from me. The high school and a tire plant were damaged according to local news reports.

[sparky]

here is a pic of some of the clouds just ahead of the squall line in Jefferson County Alabama. I know just clouds but this caught my eye saw the same set up here that later spawned tornadoes to the east of me in South Carolina.