Alert archive / Texas / Special Weather Statements in 2012

Special Weather Statement, NWS Fort Worth, TX

July 20, 2012Denton County, Jack County, Wise County, Texas

NWS Fort Worth, TX issued this special weather statement at Jul 20, 2012, 4:36 PM CDT for Denton County, Jack County, Wise County, Texas. It was in force for 24 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 20, 2012, 4:36 PM CDT (21:36 UTC)
Expired
Jul 20, 2012, 5:00 PM CDT
In force
24 min
Issued by
NWS Fort Worth, TX

Counties Denton County, TX, Jack County, TX, Wise County, TX

The radar

The Dallas/Ft Worth radar (KFWS), 59 km from the middle of the area, began a volume at 21:35 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 nearest sounding before it

Fort Worth, TX (KFWD), launched 12:00Z, 9.6 hours before the alert went out and 32 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-pSkew-T log-p diagram, Fort Worth, TX at 12:00Z on 2012-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1010 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Fort Worth, TX at 12:00Z on 2012-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
1010 J/kg
Mixed-layer CIN
-172 J/kg
Mixed-layer LCL
1582 m above ground
0-6 km bulk shear
7 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
88 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

The text

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

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What forecasters said that day

The local office's own words before this special weather statement went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Fort Worth, TX wrote its last area forecast discussion before this special weather statement went out at Jul 20, 3:47 PM CDT, 49 minutes earlier.

Area forecast discussion, Jul 20, 3:47 PM CDT, 49 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
347 PM CDT FRI JUL 20 2012

.DISCUSSION...
A SOUTHWESTWARD MOVING MESOSCALE CONVECTIVE VORTEX HAS HELPED
GENERATE ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON BETWEEN
ARCHER CITY AND GREENVILLE. THIS ACTIVITY WILL MOVE SOUTH
SOUTHEAST AND IS EXPECTED TO DISSIPATE AROUND SUNSET. HAVE
EXTENDED MENTION OF ISOLATED SHOWERS AND THUNDERSTORMS INTO THE
EVENING HOURS NORTHEAST OF A BRECKENRIDGE TO ATHENS LINE. WILL
KEEP AN EYE FOR POTENTIAL DAMAGING DOWNBURST WINDS WITH THESE
STORMS.

ANOTHER CONCERN IS THE HEAT. TEMPERATURES CLIMBED INTO THE 100 TO
106 DEGREE RANGE ALONG AND NORTH OF I-20...WITH MID 90S TO 101
DEGREES TO THE SOUTH. HEAT INDEX VALUES HAVE RISEN TO AROUND 105
DEGREES FROM WACO THROUGH THE METROPLEX AND GAINESVILLE EASTWARD THIS
AFTERNOON. HIGH TEMPERATURES AND HEAT INDEX VALUES TOMORROW WILL
BE SIMILAR. HAVE ISSUED A HEAT ADVISORY FOR DALLAS...TARRANT...DENTON
AND COLLIN COUNTIES THROUGH SATURDAY EVENING. OVERNIGHT LOWS WILL
BE IN THE UPPER 70S TO AROUND 80 IN THE METROPLEX...BUT THE REST
OF THE EASTERN TWO-THIRDS OF NORTH TEXAS WILL HAVE LOWS IN THE MID
TO UPPER 70S. IT IS BORDERLINE BUT WITH MID 70S IN MANY OF THOSE
AREAS...WE JUST DECIDED TO JUST GO THE AFOREMENTIONED COUNTIES. A
WEAK BACKDOOR FRONT IS EXPECTED TO COOL TEMPERATURES A FEW DEGREES
FOR SUNDAY. IF THIS SLIGHT COOLING DOES NOT OCCUR...THE HEAT
ADVISORY WILL NEED TO BE EXTENDED BOTH IN AREA AND TIME.

HAVE KEPT THE VERY WARM/HOT AND DRY FORECAST FOR SUNDAY THROUGH
NEXT WEEK. THERE MAY BE SOME LOW RAIN CHANCES SUNDAY AND MONDAY
ACROSS THE SOUTHEAST OR EASTERN ZONES...BUT FOR NOW HAVE JUST
PLACED 10 PERCENT POPS WITH NO SHOWERS/THUNDERSTORMS MENTIONED.

58

&&

.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX  81 105  80 102  78 /  10  10   5   5  10
WACO, TX              77 101  76  99  75 /   5  10  10  10  10
PARIS, TX             76 101  75  99  74 /  10  10  10  10  10
DENTON, TX            77 104  76 101  76 /  10  10   5   5  10
MCKINNEY, TX          78 103  77 100  75 /  10  10  10   5  10
DALLAS, TX            82 105  80 102  79 /  10  10  10   5  10
TERRELL, TX           77 103  76 100  75 /  10  10  10  10  10
CORSICANA, TX         77 102  77  99  75 /  10  10  10  10  10
TEMPLE, TX            75 100  75  99  74 /   5  10  10  10  10
MINERAL WELLS, TX     74 101  75 100  73 /  10  10   5   5  10

&&

.FWD WATCHES/WARNINGS/ADVISORIES...
HEAT ADVISORY UNTIL 8 PM CDT SATURDAY FOR TXZ103-104-118-119.

&&

85/58
Hazardous weather outlook, Jul 20, 3:32 PM CDT, 1 hour 4 minutes before
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE FORT WORTH TX
332 PM CDT FRI JUL 20 2012

TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-211145-
MONTAGUE-COOKE-GRAYSON-FANNIN-LAMAR-YOUNG-JACK-WISE-DENTON-COLLIN-
HUNT-DELTA-HOPKINS-STEPHENS-PALO PINTO-PARKER-TARRANT-DALLAS-
ROCKWALL-KAUFMAN-VAN ZANDT-RAINS-EASTLAND-ERATH-HOOD-SOMERVELL-
JOHNSON-ELLIS-HENDERSON-COMANCHE-MILLS-HAMILTON-BOSQUE-HILL-NAVARRO-
FREESTONE-ANDERSON-LAMPASAS-CORYELL-BELL-MCLENNAN-FALLS-LIMESTONE-
LEON-MILAM-ROBERTSON-
332 PM CDT FRI JUL 20 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH TEXAS.

.DAY ONE...TONIGHT.

ISOLATED THUNDERSTORMS ARE POSSIBLE NORTH OF A GRAHAM TO ENNIS
TO CANTON LINE THIS AFTERNOON. IF A STRONG STORM WERE TO
DEVELOP...IT COULD PRODUCE DAMAGING DOWNBURST WINDS.

A HEAT ADVISORY IS IN EFFECT FOR TARRANT...COLLIN...DALLAS AND
DENTON COUNTY.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY.

THE HEAT ADVISORY FOR TARRANT...COLLIN...DALLAS AND DENTON COUNTY
WILL CONTINUE THROUGH 8 PM SATURDAY.

.SPOTTER INFORMATION STATEMENT...
LIMITED SPOTTER ACTIVATION MAY BE REQUESTED NORTH OF A GRAHAM TO
ENNIS TO CANTON LINE THIS AFTERNOON.

In the hours before

Special weather statement, Jul 20, 3:46 PM CDT, 50 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
346 PM CDT FRI JUL 20 2012

TXZ104-105-119-120-202115-
DALLAS TX-HUNT TX-ROCKWALL TX-COLLIN TX-
346 PM CDT FRI JUL 20 2012

...SIGNIFICANT WEATHER ADVISORY FOR...
  COLLIN COUNTY
  NORTHEASTERN DALLAS COUNTY
  SOUTHWESTERN HUNT COUNTY
  ROCKWALL COUNTY

AT 346 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
STRONG THUNDERSTORM 7 MILES SOUTHEAST OF MCKINNEY...MOVING SOUTH AT 5
MPH.

CITIES IN THE PATH OF THIS STORM INCLUDE ALLEN...ANNA...CADDO
MILLS...FAIRVIEW...FARMERSVILLE...FATE...FRISCO...GARLAND...
GREENVILLE...HEATH...LOWRY CROSSING...LUCAS...MCKINNEY...MURPHY...
PARKER...PLANO...PRINCETON...PROSPER...RICHARDSON...ROCKWALL...
ROWLETT...ROYSE CITY...SACHSE AND WYLIE.

VERY HEAVY RAIN AND WIND GUSTS TO 50 MPH ARE LIKELY WITH THIS STORM.

LAT...LON 3333 9635 3311 9608 3284 9620 3284 9630
      3281 9630 3284 9669 3301 9685 3319 9684
      3339 9671
TIME...MOT...LOC 2046Z 349DEG 6KT 3314 9654
Special weather statement, Jul 20, 4:02 PM CDT, 34 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
402 PM CDT FRI JUL 20 2012

TXZ101>103-202130-
DENTON TX-JACK TX-WISE TX-
402 PM CDT FRI JUL 20 2012

...SIGNIFICANT WEATHER ADVISORY FOR...
  DENTON COUNTY
  JACK COUNTY
  WISE COUNTY

AT 402 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
STRONG THUNDERSTORM 8 MILES WEST OF DENTON...MOVING SOUTH AT 10 MPH.

VERY HEAVY RAIN AND DAMAGING WIND GUSTS TO 55 MPH ARE LIKELY WITH
THIS STORM.

CITIES IN THE PATH OF THIS STORM INCLUDE ALVORD...ARGYLE...AUBREY...
BARTONVILLE...BOYD...BRIDGEPORT...BRYSON...CHICO...COPPER CANYON...
CORINTH...CORRAL CITY...CROSS ROADS...DECATUR...DENTON...DOUBLE
OAK...FLOWER MOUND...HACKBERRY...HEBRON...HICKORY CREEK...HIGHLAND
VILLAGE...JACKSBORO...JUSTIN...KRUGERVILLE...KRUM...LAKE DALLAS...
LEWISVILLE...LITTLE ELM...NORTHLAKE...PILOT POINT...SANGER...SHADY
SHORES...THE COLONY...COTTONDALE...RAY ROBERTS PARK ISLE DU BOIS AND
LAKE LEWISVILLE.

LAT...LON 3345 9798 3343 9797 3344 9764 3340 9684
      3300 9684 3313 9843 3347 9842
TIME...MOT...LOC 2102Z 342DEG 9KT 3322 9726
Special weather statement, Jul 20, 4:20 PM CDT, 16 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
420 PM CDT FRI JUL 20 2012

TXZ104-119-202145-
DALLAS TX-COLLIN TX-
420 PM CDT FRI JUL 20 2012

...SIGNIFICANT WEATHER ADVISORY FOR...
  SOUTHWESTERN COLLIN COUNTY
  NORTHERN DALLAS COUNTY

AT 419 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
SEVERAL STRONG THUNDERSTORMS ACROSS PORTIONS COLLIN AND DALLAS
COUNTIES...MOVING SLOWLY SOUTH.

DAMAGING WIND GUSTS TO 55 MPH ARE LIKELY WITH ANY OF THESE STORMS.

LAT...LON 3319 9647 3298 9649 3298 9652 3264 9652
      3287 9696 3299 9703 3299 9685 3332 9683
TIME...MOT...LOC 2119Z 337DEG 7KT 3292 9666
Special weather statement, Jul 20, 4:36 PM CDT, 0 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
436 PM CDT FRI JUL 20 2012

TXZ101>103-118-202200-
DENTON TX-JACK TX-TARRANT TX-WISE TX-
436 PM CDT FRI JUL 20 2012

...SIGNIFICANT WEATHER ADVISORY FOR...
  DENTON COUNTY
  JACK COUNTY
  NORTHERN TARRANT COUNTY
  WISE COUNTY

AT 436 PM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED
STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 12 MILES WEST OF
JACKSBORO TO 11 MILES NORTHWEST OF TROPHY CLUB...MOVING SOUTH AT 20
MPH.

WIND GUSTS TO 55 MPH AND VERY HEAVY RAINFALL ARE LIKELY WITH THESE
STORMS.

CITIES IN THE PATH OF THESE STORMS INCLUDE ARGYLE...AURORA...AZLE...
BARTONVILLE...BOYD...BRIDGEPORT...BRYSON...CHICO...COLLEYVILLE...
COPPER CANYON...CORINTH...CORRAL CITY...DECATUR...DENTON...DOUBLE
OAK...EAGLE MOUNTAIN...FLOWER MOUND...GRAPEVINE...HACKBERRY...
HASLET...HEBRON...HICKORY CREEK...HIGHLAND VILLAGE...JACKSBORO...
JUSTIN...KELLER...KRUM...LAKE DALLAS...LEWISVILLE...LITTLE ELM...
NORTHLAKE...PECAN ACRES...PELICAN BAY...ROANOKE...SHADY SHORES...
SOUTHLAKE...THE COLONY...TROPHY CLUB...BOONSVILLE...COTTONDALE AND
LAKE LEWISVILLE.

LAT...LON 3331 9725 3315 9684 3300 9686 3299 9704
      3289 9704 3287 9755 3299 9755 3302 9842
      3342 9841
TIME...MOT...LOC 2136Z 007DEG 20KT 3316 9837 3305 9735

The office that day

Everything else NWS Fort Worth, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 20, 2:57 PM CDTHeat AdvisoryFWDCollin, Cooke, Dallas, Delta, Denton, Fannin and 16 more53 hr
Jul 20, 3:46 PM CDTSpecial Weather StatementFWDCollin, Rockwall29 min
Jul 20, 4:02 PM CDTSpecial Weather StatementFWDDenton, Jack, Wise28 min
Jul 20, 4:20 PM CDTSpecial Weather StatementFWDCollin25 min
Jul 20, 4:46 PM CDTSpecial Weather StatementFWDCollin, Dallas, Rockwall29 min
Jul 20, 4:56 PM CDTSpecial Weather StatementFWDJack, Young34 min
Jul 20, 5:08 PM CDTSpecial Weather StatementFWDKaufman37 min
Jul 20, 5:34 PM CDTSpecial Weather StatementFWDPalo Pinto, Young26 min
Jul 20, 5:37 PM CDTSpecial Weather StatementFWDDallas, Tarrant23 min
Jul 20, 5:42 PM CDTSpecial Weather StatementFWDParker33 min
Jul 20, 5:50 PM CDTSevere Thunderstorm WarningFWDDallas, Tarrant25 min
Jul 20, 6:05 PM CDTSpecial Weather StatementFWDDallas, Tarrant25 min
Jul 20, 6:14 PM CDTSpecial Weather StatementFWDJohnson31 min
Jul 20, 6:17 PM CDTSpecial Weather StatementFWDParker28 min
Jul 20, 6:25 PM CDTSevere Thunderstorm WarningFWDDallas24 min
Jul 20, 6:38 PM CDTSpecial Weather StatementFWDDallas, Johnson, Tarrant37 min

Nearby

Special Weather Statements in Texas, 2012Every special weather statement in 2012

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.