Alert archive / Texas / Mesoscale Discussions in 2005

Mesoscale Discussion 596

April 19, 2005Harmon County, Oklahoma; 19 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2005, 5:07 PM CDT for Harmon County, Oklahoma; 19 counties in Texas. It was in force for 83 min.

The area

The outline as issued.

The facts

Issued: Apr 19, 2005, 5:07 PM CDT (22:07 UTC)
Expired: Apr 19, 2005, 6:30 PM CDT
In force: 83 min
Issued by: the Storm Prediction Center

Counties Harmon County, OK, Baylor County, TX, Callahan County, TX, Childress County, TX, Coke County, TX, Cottle County, TX, Fisher County, TX, Foard County, TX, Hardeman County, TX, Haskell County, TX, Jones County, TX, King County, TX, Knox County, TX, Nolan County, TX, Runnels County, TX, Shackelford County, TX, Stonewall County, TX, Taylor County, TX, Throckmorton County, TX, Wilbarger County, TX

The radar

The Dyess AFB radar (KDYX), 82 km from the middle of the area, began a volume at 22:09 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 164Apr 19, 5:30 PM CDT

The nearest sounding before it

Fort Sill, OK (KFSI), launched 12:00Z, 10.1 hours before the alert went out and 235 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 156 J/kg
Mixed-layer CIN: -339 J/kg
Mixed-layer LCL: 930 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 349 m²/s²
0-3 km storm-relative helicity: 507 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
ACUS11 KWNS 192207
SWOMCD
SPC MCD 192207 
TXZ000-OKZ000-192330-

MESOSCALE DISCUSSION 0596
NWS STORM PREDICTION CENTER NORMAN OK
0507 PM CDT TUE APR 19 2005

AREAS AFFECTED...PORTIONS W3-CENTRAL/NW TX...EXTREME SWRN OK

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 192207Z - 192330Z

SEVERE TSTM DEVELOPMENT IS POSSIBLE THROUGH 20/00Z WITHIN CORRIDOR
LOCATED ALONG AND ABOUT 50 NM E OF SFC DRYLINE...FROM CDS/HOLLIS
AREAS SWD TOWARD SJT.  DAMAGING HAIL AND GUSTS ARE POSSIBLE FROM
SUPERCELLS.  WW MAY BE REQUIRED.

AIR MASS HAS LOST ALMOST ALL SBCINH ACROSS THIS REGION...BASED ON
MODIFIED RUC SOUNDINGS AS WELL AS CLUMPS OF TCU NOTED IN VIS
IMAGERY.  DEEPEST CONVECTIVE TOWERS ATTM -- AND MOST PROBABLE AREA
FOR FIRST CONVECTIVE INITIATION -- IS OVER PORTIONS
KNOX/HASKELL/STONEWALL COUNTIES TX.  AIR MASS IS FAVORABLY
BUOYANT...WITH MOIST SECTOR SFC DEW POINTS MID-UPPER 50S F
CONTRIBUTING TO MLCAPES AROUND 2000 J/KG.  AS MIXING WEAKENS
SOMEWHAT...DEW POINTS MAY RISE INTO LOWER 60S F AS OBSERVED AOA 50
NM E OF SFC DRYLINE.  EXPECT LITTLE MOTION BOTH OF DRYLINE AND OF
TSTMS THEMSELVES...THEREFORE SEVERE THREAT IS NARROW IN ZONAL
EXTENT.  MODIFIED RUC HODOGRAPHS YIELD 0-1 KM AGL SRH 150-175
J/KG...THOUGH SIGNIFICANT WEAKNESSES ARE EVIDENT IN FLOW PROFILES IN
2-4 KM LAYER.

..EDWARDS.. 04/19/2005

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

ATTN...WFO...FWD...OUN...SJT...LUB...AMA...MAF...

32380067 34120042 34950026 34909991 34439929 34059912
33579900 32709913 31979947 31639993 31480024 31490057
31700073

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 19, 5:30 PM CDT	Severe Thunderstorm Watch	SPC	Harmon, Jackson, Tillman	6 hr
Apr 19, 5:49 PM CDT	Mesoscale Discussion	SPC	Beckham, Ellis, Greer, Harper, Roger Mills, Woodward	116 min
Apr 18, 9:09 PM CDT	Mesoscale Discussion	SPC	Childress, Cottle, Floyd, Foard, Hall, Hardeman and 1 more	96 min
Apr 19, 3:55 PM CDT	Mesoscale Discussion	SPC	Crockett, Edwards, Irion, Menard, Pecos, Reagan and 7 more	95 min
Apr 19, 6:10 PM CDT	Severe Thunderstorm Watch	SPC	Dimmit, Edwards, Kinney, La Salle, Maverick, Real and 4 more	5 hr

Nearby

Mesoscale Discussions in Texas, 2005 Mesoscale Discussions in Oklahoma, 2005 Every mesoscale discussion in 2005

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.