[MCD] SWOMCD

Fri Apr 21 09:21:44 UTC 2006

ACUS11 KWNS 210913
SWOMCD
SPC MCD 210913 
TXZ000-211115-

MESOSCALE DISCUSSION 0599
NWS STORM PREDICTION CENTER NORMAN OK
0413 AM CDT FRI APR 21 2006

AREAS AFFECTED...PORTIONS S-CENTRAL/SE TX.

CONCERNING...SEVERE THUNDERSTORM WATCH 230...

VALID 210913Z - 211115Z

QUASI-LINEAR CONVECTIVE COMPLEX HAS EVOLVED FROM PREVIOUSLY BROKEN
BAND OF DISCRETE CELLS AND...AS OF 845Z...EXTENDED FROM SRN FRINGES
SAT METRO AREA NEWD TO NRN BRAZOS COUNTY.  MOST VIGOROUS CONVECTION
SHOULD CROSS AREA FROM VCT THROUGH HOU.  ALTHOUGH A FEW ELEVATED
TSTMS MAY DEVELOP OVER REINFORCING OUTFLOW POOL...SEVERE THREAT
SHOULD BE RELATIVELY MEAGER WITH SUCH ACTIVITY...AND WW MAY BE
CLEARED FROM NW-SE AS MCS MOVES BY.  PROSPECTIVE PATH OF MCS --
TOWARD MIDDLE-UPPER TX COAST -- MAY REQUIRE WW SOON.

AIR MASS AHEAD OF THESE TSTMS...ACROSS SE TX...APPEARS FAVORABLE FOR
MCS TO MOVE GENERALLY ESEWD DURING NEXT FEW HOURS...PRODUCING
OCCASIONAL HAIL.  DAMAGING GUSTS ALSO ARE POSSIBLE IN MIDDLE-SRN
PORTION OF MCS...WHERE NEAR-SFC STABLE LAYER IS SHALLOWEST...AND
MOST PENETRABLE BY STRONG-SEVERE DOWNDRAFTS.  SFC MESOANALYSIS SHOWS
QUASISTATIONARY BAROCLINIC BOUNDARY FROM NEAR SABINE/NEWTON COUNTY
LINE WSWWD NEAR IAH...THEN APPROXIMATELY 50 N VCT...BEFORE BEING
OVERTAKEN BY SRN PORTION OF MCS.  MODIFIED RUC SOUNDINGS SHOW LIFTED
PARCELS S OF BOUNDARY ARE SFC-BASED OR NEARLY SO.  HOWEVER...THESE
PARCELS ARE RESTRICTED FROM ASCENT BY CAPPING IN 750-850 MB
LAYER...WHICH INCREASES WITH SRN EXTENT.  LLJ HAS INCREASED TO 40 KT
S OF MCS...PER CRP VWP TRENDS. MCS MAY BACKBUILD SLGTLY AMIDST
FAVORABLE STORM-RELATIVE INFLOW AND MUCAPES AROUND 1500 J/KG.
HOWEVER...ANTICIPATE MAJORITY OF ACTIVITY WILL RESULT FROM FORCED
ASCENT TO LFC...ALONG THAT PORTION OF OUTFLOW EDGE IN AND S OF SFC
FRONTAL ZONE.

..EDWARDS.. 04/21/2006

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...HGX...FWD...CRP...EWX...

29209947 29429891 29749811 30259751 30649699 30799663
30509549 29649502 28729562 28109671 28009752 28399917
28529971 28610000 28830010 28920006 29029989 