Backside Anvil

Self portrait with inflow jet.

-Steve

Just one from tonight's chase ...

Shot just east of Panhandle, Texas on Hwy 60 East of Amarillo at sunset.

I'll post later - but I'm running out of adrenaline and very tired. Check back in the morning.

(C) Steve Douglass

Latest weather outlook

NWS STORM PREDICTION CENTER NORMAN OK
0259 PM CDT WED APR 29 2009

AREAS AFFECTED...TX/OK PANHANDLES...SWRN KS

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 291959Z - 292130Z

SEVERE THREAT WILL INCREASE AS ISOLATED TO SCATTERED TSTMS SHOULD
INITIATE ACROSS SERN CO INTO THE TX PANHANDLE. VERY STEEP
LOW/MID-LEVEL LAPSE RATES RESULTING IN MODERATE INSTABILITY WILL
SUPPORT POTENTIAL FOR LARGE HAIL AND DAMAGING WINDS. HOWEVER...WEAK
MID/HIGH-LEVEL FLOW MAY TEMPER THE AMPLITUDE AND AREAL EXTENT OF THE
OVERALL THREAT. THE AREA WILL CONTINUE TO BE MONITORED FOR A
POSSIBLE WW.

RECENT VISIBLE SATELLITE/SURFACE ANALYSIS DEPICT TCU BUILDUPS
INCREASING ACROSS FAR SERN CO NEAR A CYCLONE CENTERED AROUND 30 SE
LAA AND IN PATCHES ALONG THE DRY LINE THAT EXTENDED SWD THROUGH THE
TX PANHANDLE. THE MOST LIKELY AREA OF TSTM INITIATION SHOULD BE NEAR
THE SURFACE LOW WHERE CONVERGENCE APPEARS GREATEST. THIS SHOULD THEN
EVOLVE EWD INTO AN AXIS OF MODERATE TO STRONG INSTABILITY LYING FROM
SWRN KS THROUGH WRN TX WITH MLCAPES OF 2000 TO 3000 J/KG. ALTHOUGH
AREA PROFILER/VWP DATA INDICATE RATHER MODEST MID/HIGH-LEVEL FLOW
BETWEEN BELTS OF STRONGER NRN/SRN STREAM WLYS...VEERED KINEMATIC
PROFILES SHOULD BE SUFFICIENT FOR UPDRAFT ORGANIZATION GIVEN THE
PRESENCE OF STEEP LOW/MID-LEVEL LAPSE RATES. LARGE HAIL AND SEVERE
WINDS WOULD LIKELY BE THE PRIMARY THREATS WITH PERHAPS AN ISOLATED
TORNADO.

Today's Severe Forecast

DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0751 AM CDT WED APR 29 2009

VALID 291300Z - 301200Z

...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE SRN AND CNTRL
PLNS...

...SYNOPSIS...
BROAD BAND OF LOW AMPLITUDE CYCLONIC FLOW WILL PERSIST ACROSS THE
PLNS...S AND E OF ELONGATING UPR LOW OVER THE PACIFIC NW/NRN RCKYS.
THE LOW SHOULD REDEVELOP E INTO THE NRN PLNS TONIGHT/EARLY THU AS
STRONG SPEED MAX NOW ENTERING THE NRN GRT BASIN CONTINUES ENE INTO
WY AND THE DAKOTAS. FARTHER S...A SPEED MAX IN THE WEAKER SRN
STREAM...NOW OVER NW MEXICO/SRN AZ...SHOULD REACH WRN/CNTRL TX BY
EVE...AND LA/AR EARLY THU.

AT THE SFC...EXPECT DIFFUSE WARM FRONT TO CONTINUE REDEVELOPING NWD
ACROSS THE SRN/CNTRL PLNS...WHILE A SEPARATE WARM FRONT EVOLVES MUCH
FARTHER N ACROSS THE NRN PLNS/UPR MS VLY IN ASSOCIATION WITH LEE
CYCLONE IN WRN SD. OVER THE SRN PLNS...A REMNANT FRONTAL
SEGMENT/OUTFLOW BOUNDARY LIKELY WILL PERSIST FOR AT LEAST PART OF
THE DAY INVOF THE RED RVR AND NW TX.

...SRN PLNS...
LOOSELY-ORGANIZED MCS NOW OVER NW TX/SW OK SHOULD CONTINUE GENERALLY
E THROUGH THE MORNING...WITH NEW CELL DEVELOPMENT MOST LIKELY ON ITS
SRN AND SERN FLANKS. RELATIVE WEAKNESS IN THE 700-500 MB FLOW
LIKELY WILL LIMIT STRENGTH/LONGEVITY OF INDIVIDUAL STORMS. BUT
GIVEN QUALITY OF MOIST INFLOW /PW AROUND 1.40 INCHES/ AND LOW LVL
SHEAR ASSOCIATED WITH 40+ KT LLJ...POTENTIAL WILL REMAIN FOR
EMBEDDED LEWPS/SMALL BOWS WITH WET MICROBURSTS AND MARGINALLY SVR
HAIL.

SW OF THE MCS...STRONG SFC HEATING SHOULD OCCUR THIS AFTN ALONG AND
S OF TRAILING OUTFLOW BOUNDARY/LINGERING WARM FRONTAL SEGMENT OVER
NW AND W CNTRL TX. COMBINATION OF HEATING WITH RICH BOUNDARY LAYER
MOISTURE AND STEEP MID LVL LAPSE RATES SHOULD BOOST SBCAPE TO AOA
2500 J/KG. MAX SFC TEMPERATURES SHOULD OCCUR JUST ABOUT THE TIME
THAT LEADING EDGE OF PREVIOUSLY-MENTIONED SRN STREAM SPEED MAX
OVERSPREADS THE REGION. WITH 500 MB WSWLY FLOW INCREASING TO AOA 40
KTS...SETUP SHOULD PROVE FAVORABLE FOR DEVELOPMENT OF DISCRETE
SUPERCELLS. THESE COULD PRODUCE A FEW TORNADOES...IN ADDITION TO
VERY LARGE HAIL AND LOCALLY DMGG WINDS THROUGH EARLY TONIGHT.

...CNTRL PLNS...
SFC-BASED INSTABILITY WILL ALSO INCREASE OVER THE CNTRL PLNS TODAY
AS HEATING OCCURS ALONG AXIS OF LOW LVL MOISTURE RETURN WITH LLJ.
THE GREATEST DESTABILIZATION SHOULD OCCUR ALONG WRN EDGE OF THE LLJ
IN WRN KS...WHERE HEATING WILL BE MAXIMIZED BENEATH EML. FARTHER
N...DESTABILIZATION MAY MAXIMIZE ALONG DEVELOPING COLD FRONT/TROUGH
IN WRN/CNTRL NEB AND S CNTRL SD. FORCING FOR ASCENT SHOULD REMAIN
WEAK AS REGION WILL LIE S OF GRT BASIN SPEED MAX AND N OF JET STREAK
AFFECTING THE SRN PLNS. BUT LOW LVL CONVERGENCE ALONG LEE
TROUGH/DRY LINE IN KS...ALONG COLD FRONT IN NEB...AND NEAR TRIPLE
POINT IN SD...SHOULD SUPPORT SCTD AFTN/EVE STORMS. SOME OF THESE
COULD BECOME WEAK SUPERCELLS OR AT LEAST SUFFICIENTLY SUSTAINED TO
YIELD LARGE HAIL/LOCALLY DMGG WIND AND PERHAPS A TORNADO.

FARTHER E...STRONG TSTMS WILL ALSO BE POSSIBLE ALONG WARM FRONT
SEGMENT OVER THE LWR MO VLY...WHERE MOISTURE WILL INCREASE ALONG LLJ
ON ERN FRINGE OF EML. RELATIVELY WEAK LARGE SCALE FORCING FOR
ASCENT AND LIMITED SFC HEATING SHOULD LIMIT ASSOCIATED SVR THREAT.

...AR/TN VLY...
SFC HEATING INVOF DIFFUSE WARM FRONT AND/OR ON ERN FRINGE OF CLOUD
SHIELD ASSOCIATED WITH OK/TX MCS SHOULD YIELD A FAVORABLE
THERMODYNAMIC ENVIRONMENT FOR AFTN STORMS OVER PARTS OF AR AND THE
TN VLY GIVEN A NWD SURGE OF MOISTURE ON ERN SIDE OF SRN PLNS LLJ.
HOWEVER...REGION WILL BE WELL REMOVED FROM STRONGER FLOW ALOFT...
AND MID LVL LAPSE RATES WILL REMAIN WEAK. THUS...OVERALL SVR THREAT
SHOULD BE LOW.

..CORFIDI/SMITH.. 04/29/2009