Widespread showers and thunderstorms developed in an environment aided by diffluence aloft. Although they did not produce severe weather on the 17th, they did produce minor flash flooding along Interstate 35E in the Lewisville area in Denton County.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS FWD wrote it up.
Widespread showers and thunderstorms developed in an environment aided by diffluence aloft. Although they did not produce severe weather on the 17th, they did produce minor flash flooding along Interstate 35E in the Lewisville area in Denton County.
The local office's own words before the first event, 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 the first event at Aug 17, 8:04 AM CST, 1 hour 36 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FORT WORTH TX 904 AM CDT SUN AUG 17 2014 .UPDATE... CONVECTION DEVELOPED OVERNIGHT NEAR YESTERDAY/S MCV LEADING TO AN AREA OF RAIN AND STORMS GENERALLY NEAR THE METROPLEX. THE MORNING BALLOON SHOWS PRECIPITABLE WATER IS WELL ABOVE 2 INCHES...BUT THERE IS A LAYER OF DRIER AIR IN THE LOW LEVELS THAT IS KEEPING THE HEAVY RAINFALL THREAT LOCALIZED BENEATH THE STRONGER THUNDERSTORM CORES. OUTSIDE OF STORMS...A LOT OF THE PRECIPITATION IS EVAPORATING BEFORE REACHING THE GROUND WHICH IS LIMITING RAINFALL RATES AND AMOUNTS. THIS CONVECTIVE COMPLEX WILL CONTINUE OVER THE CENTRAL PARTS OF THE CWA THROUGH THE NEXT FEW HOURS...BUT WILL LIKELY DIMINISH IN COVERAGE AND INTENSITY EARLY THIS AFTERNOON. HOWEVER ADDITIONAL CONVECTION SHOULD POP UP OVER MAINLY THE SOUTHERN ZONES THIS AFTERNOON WHERE STRONGER DAYTIME HEATING WILL OCCUR. HAVE UPDATED TO LOWER HIGH TEMPS WHERE RAINFALL WILL BE MOST PREVALENT THIS MORNING...AND HAVE AMENDED SHORT TERM POPS TO ALIGN WITH RADAR TRENDS AND THE EXPECTED DECAY AND GENERAL SOUTHWARD TRANSITION OF CONVECTIVE ACTIVITY BY AFTERNOON. TR.92 && .AVIATION... /ISSUED 642 AM CDT SUN AUG 17 2014/ /12Z TAFS/ CONCERNS...THUNDER AT THE AIRPORTS THE NEXT 24 HOURS. THE CONVECTIVE TRENDS OVER THE NEXT 24 HOURS IS QUITE A CHALLENGE AND DEPENDS ON SEVERAL SMALL SCALE AND LARGER SCALE FEATURES. THUNDERSTORMS ARE CURRENTLY MOVING THROUGH THE METROPLEX WITH SCATTERED SHOWERS STARTING TO DEVELOP NORTH AND WEST OF THE KACT AIRPORT. HIGH MOISTURE CONTENT IN THE ATMOSPHERE THIS MORNING IS ALLOWING FOR THE SHOWERS AND STORMS TO PRODUCE HIGH RAINFALL RATES RESULTING IN PERIODS OF HEAVY RAIN AND REDUCED VISIBILITIES. SHORT TERM MODELS INDICATE THERE COULD BE A SHORT BREAK IN THE SHOWERS AND STORMS THIS MORNING...BUT THERE ALSO MAY CONTINUE TO BE ISOLATED ACTIVITY THROUGH THE MORNING AS LARGE SCALE LIFT FROM AN APPROACHING SHORTWAVE SPREADS OVER THE REGION. WILL CONTINUE WITH A VCTS MENTION IN THE METROPLEX AND A VCSH MENTION THROUGH THE MORNING HOURS. BETTER CHANCES FOR RAIN/STORMS ARE EXPECTED AGAIN THIS AFTERNOON AND WILL CARRY VCTS INTO THE AFTERNOON HOURS FOR ALL THE TAF SITES. WILL ALSO TEMPO FOR THUNDER FOR MUCH OF THE AFTERNOON AND EARLY EVENING HOURS. ANY THUNDERSTORMS THIS AFTERNOON OR EVENING COULD PRODUCE STRONG WINDS OR DAMAGING DOWNBURSTS AND THE TEMPOS MAY HAVE TO BE UPDATED TO REFLECT THIS. RAIN CHANCES OVERNIGHT WILL SHIFT TO AREAS SOUTH OF INTERSTATE 20 AND WILL CONTINUE WITH A VCSH MENTION OVERNIGHT AT KACT BUT REMOVE THE PRECIPITATION FROM THE METROPLEX TAF SITES. IT IS POSSIBLE THUNDERSTORMS MAY OCCUR OVERNIGHT AROUND KACT BUT THEY SHOULD BE MORE ISOLATED IN NATURE. 82/JLD && .PREV DISCUSSION... /ISSUED 346 AM CDT SUN AUG 17 2014/ MORE CHALLENGES LIE AHEAD TODAY INTO MONDAY AS NORTH TEXAS REMAINS UNDERNEATH WEAK DIFFLUENT MID LEVEL FLOW ALOFT. THERE ARE MANY FEATURES ALOFT TO NOTE. AN UPPER HIGH CONTINUED TO BE CENTERED OVER ARIZONA WHILE A STRONG SHORTWAVE WAS MOVING SOUTHEAST OVER THE MID MISSISSIPPI VALLEY. A VORTICITY AXIS TRAILED SOUTHWEST FROM THIS DISTURBANCE INTO OKLAHOMA AND THE TEXAS PANHANDLE. IN ADDITION...A TUTT LOW REMAINED OVER THE WESTERN GULF OF MEXICO. MEANWHILE...THE ENVIRONMENT REMAINS VERY MOIST WITH PWATS EXPECTED TO BE BETWEEN 1.8 AND 2.2 INCHES THROUGH MONDAY. AT THE SURFACE THERE WAS A WEAK LOW NEAR THROCKMORTON WITH AN OUTFLOW BOUNDARY SLIDING SOUTHEAST ACROSS OUR WESTERN COUNTIES. ALSO...A MESOSCALE VORTEX /MCV/ WAS NOTED ON REGIONAL RADARS TRACKING EAST ACROSS THE RED RIVER VALLEY EARLY THIS MORNING. HOW EACH OF THESE FEATURES AFFECTS THE FORECAST THROUGH TONIGHT IS UNCERTAIN...BUT WE CERTAINLY HAVE TO ACCOUNT FOR ALL OF THEM. PER CURRENT WEATHER TRENDS...IT APPEARS THE HRRR/RAP AND WRF EAST MODELS HAVE THE BEST HANDLE ON THINGS WITH THE TX TECH WRF A PLAUSIBLE SECONDARY OPTION. THE CONVECTIVELY-INDUCED MCV ALONG THE RED RIVER VALLEY WILL BE THE MAIN FOCUS THIS MORNING AND WILL CARRY LIKELY RAIN CHANCES FROM DFW NORTHEAST TOWARD PARIS. THIS AFTERNOON WILL BE MORE CHALLENGING REGARDING HOW THINGS PLAY OUT. DAYTIME HEATING...OUTFLOW BOUNDARIES...SUBSIDENCE BEHIND THE MORNING MCV AND THE VORTICITY AXIS ALL COULD PLAY ROLES ON CONVECTIVE EVOLUTION. WE HAVE PLACED HIGHEST RAIN CHANCES ALONG AND JUST SOUTH OF I-20 FOR THIS AFTERNOON AS THE OUTFLOW BOUNDARY STALLS. SUBSIDENCE BEHIND THE MORNING MCV SHOULD BE MORE NEGLIGIBLE ACROSS THESE AREAS AS WELL. ACQUIRED POPS WERE LOWERED INTO THE CHANCE CATEGORY DUE TO THE AFOREMENTIONED UNCERTAINTY. CURRENT THINKING IS THE OUTFLOW BOUNDARY SETS UP THIS AFTERNOON JUST SOUTH OF I-20. SHOWERS AND STORMS THAT DEVELOP WILL BE SLOW MOVERS WITH ONLY WEAK WEST-NORTHWEST FLOW ALOFT. LOCALIZED VERY HEAVY RAINFALL AND FLOODING IS HIGHLY POSSIBLE DUE TO THE VERY MOIST ATMOSPHERE IN PLACE. THE BULK OF THE RICHER MOISTURE WILL BE ELEVATED...THOUGH LOW LEVELS ARE SLIGHTLY MORE MOIST TODAY VERSUS YESTERDAY. ENOUGH DRY AIR ALOFT WILL EXIST FOR PRECIPITATION LOADING AND LOCALIZED DOWNBURST WINDS ONCE AGAIN WITH STRONGER STORMS. WE WILL FOCUS BEST RAIN CHANCES SOUTH OF I-20 TONIGHT INTO MONDAY AS THE VORT AXIS PROGRESSES THROUGH THE AREA AND WHERE SURFACE BOUNDARIES ARE LIKELY TO SET UP. LOCALLY HEAVY RAINFALL AND FLOODING WILL CONTINUE TO BE A CONCERN. AT THIS TIME...HEAVIER RAINS ARE NOT EXPECTED TO BE WIDESPREAD AND WE DO NOT ANTICIPATE ISSUING ANY FLOOD OR FLASH FLOOD WATCHES. SUBSIDENCE BEGINS TAKING HOLD LATER MONDAY NIGHT INTO TUESDAY...AS THE VORT AXIS SLIDES OVER AND EVENTUALLY EXITS THE AREA. ENOUGH RESIDUAL MOISTURE WILL RESIDE FOR ISOLATED AFTERNOON/EVENING STORMS ON TUESDAY AND HAVE LET THAT RIDE IN THE FORECAST. BY WEDNESDAY...THE UPPER HIGH SLIDES EAST IN RESPONSE TO AN UPPER LEVEL TROUGH DEEPENING OVER THE FAR WESTERN U.S. THE UPPER HIGH WILL STRENGTHEN AND ANCHOR OVER THE SOUTHEAST U.S FOR THE LATTER HALF OF THE WEEK INTO NEXT WEEKEND. NORTH TEXAS WILL BE UNDERNEATH THE WESTERN SIDE OF THE UPPER HIGH. HIGH TEMPERATURES WILL HEAT UP AND REACH THE CENTURY MARK ONCE AGAIN ACROSS PARTS OF THE AREA. THE UPPER HIGH APPEARS STRONGER OVER OUR AREA VERSUS YESTERDAY/S MODEL RUNS WHICH MEANS SUBSIDENCE WILL BE STRONGER AS WELL. HAVE LEFT THE ENTIRE CWA RAIN FREE THE LATTER HALF OF THE WEEK INTO NEXT WEEKEND. 05/ && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 90 77 99 78 100 / 60 20 20 10 10 WACO, TX 91 75 99 76 99 / 40 40 30 10 10 PARIS, TX 88 72 96 73 96 / 90 20 10 10 10 DENTON, TX 92 75 99 75 100 / 40 20 10 10 10 MCKINNEY, TX 90 74 98 74 99 / 90 20 10 10 10 DALLAS, TX 90 78 99 79 99 / 80 20 20 10 10 TERRELL, TX 88 75 98 75 99 / 90 20 30 10 10 CORSICANA, TX 89 75 97 75 98 / 40 40 30 10 10 TEMPLE, TX 94 75 98 74 99 / 40 40 20 10 10 MINERAL WELLS, TX 94 73 99 73 101 / 30 20 20 10 10 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && /
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE FORT WORTH TX 339 AM CDT SUN AUG 17 2014 TXZ091>095-100>107-115>123-129>135-141>148-156>162-174-175-181200- 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- 339 AM CDT SUN AUG 17 2014 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH TEXAS. .DAY ONE...TODAY AND TONIGHT. THERE IS A CHANCE OF THUNDERSTORMS ACROSS THE REGION TODAY THROUGH TONIGHT. THE BEST RAIN CHANCES WILL BE SOUTHEAST OF A LINE FROM EASTLAND TO FORT WORTH TO BONHAM. LIGHTNING...PERIODS OF HEAVY RAINFALL AND STRONG WINDS WILL BE THE MAIN HAZARDS BUT SOME THUNDERSTORMS IN THE AFTERNOON AND EARLY EVENING HOURS WILL BE CAPABLE OF PRODUCING DAMAGING DOWNBURST WINDS. IN ADDITION...STRONG OUTFLOW WINDS WILL POSE A THREAT TO THOSE INVOLVED IN OUTDOOR RECREATION ACTIVITIES...ESPECIALLY ON AREA LAKES. AREAS THAT RECEIVE HEAVY RAINFALL COULD EXPERIENCE LOCALIZED FLOODING PROBLEMS. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY. LOW THUNDERSTORM CHANCES WILL CONTINUE ALONG AND SOUTH OF INTERSTATE 20 ON MONDAY. ISOLATED THUNDERSTORMS ARE POSSIBLE TUESDAY AFTERNOON. ISOLATED SEVERE DOWNBURST WINDS...PERIODS OF HEAVY RAINFALL AND FREQUENT LIGHTNING WILL REMAIN THE PRIMARY HAZARDS...ESPECIALLY DURING THE AFTERNOON AND EVENING PERIODS. .SPOTTER INFORMATION STATEMENT... LIMITED SPOTTER ACTIVATION MAY BE REQUESTED THIS AFTERNOON THROUGH THE EARLY EVENING HOURS. 82/JLD
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE FORT WORTH TX 553 AM CDT SUN AUG 17 2014 TXZ104-171130- COLLIN TX- 553 AM CDT SUN AUG 17 2014 ...SIGNIFICANT WEATHER ADVISORY FOR... SOUTH CENTRAL COLLIN COUNTY AT 553 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A STRONG THUNDERSTORM 4 MILES WEST OF WYLIE...MOVING NORTHEAST AT 5 MPH. CITIES IN THE PATH OF THIS STORM INCLUDE LUCAS...MURPHY...PARKER AND WYLIE. VERY HEAVY RAIN AND WIND GUSTS TO 40 MPH ARE LIKELY WITH THIS STORM. THE HEAVY RAIN MAY RESULT IN THE FLOODING OF LOW LYING AREAS...CREEKS...AND DITCHES. LAT...LON 3318 9657 3302 9638 3298 9658 3305 9667 TIME...MOT...LOC 1053Z 232DEG 4KT 3305 9658 82/JLD
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FORT WORTH TX
609 AM CDT SUN AUG 17 2014
TXZ104-171145-
COLLIN TX-
609 AM CDT SUN AUG 17 2014
...SIGNIFICANT WEATHER ADVISORY FOR...
NORTHWESTERN COLLIN COUNTY
AT 609 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED A
STRONG THUNDERSTORM 6 MILES NORTHWEST OF MCKINNEY...MOVING NORTHEAST
AT 15 MPH.
CITIES IN THE PATH OF THIS STORM INCLUDE ALLEN...ANNA...CELINA...
FAIRVIEW...LOWRY CROSSING...MCKINNEY AND PROSPER.
VERY HEAVY RAIN AND WIND GUSTS TO 40 MPH ARE LIKELY WITH THIS STORM.
HEAVY RAINFALL MAY RESULT IN FLOODING OF LOW LYING AREAS SUCH AS
DITCHES AND UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED
ROADS AS THEY MAY BE WASHED OUT.
LAT...LON 3340 9653 3339 9652 3320 9648 3308 9672
3323 9681 3341 9683 3340 9656
TIME...MOT...LOC 1109Z 238DEG 15KT 3326 9672
82/JLDSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE FORT WORTH TX 716 AM CDT SUN AUG 17 2014 TXZ119-171315- DALLAS TX- 716 AM CDT SUN AUG 17 2014 ...SIGNIFICANT WEATHER ADVISORY FOR... WESTERN DALLAS COUNTY AT 716 AM CDT...NATIONAL WEATHER SERVICE METEOROLOGISTS DETECTED STRONG THUNDERSTORMS ALONG A LINE EXTENDING FROM 2 MILES SOUTHEAST OF COPPELL TO GRAND PRAIRIE...MOVING EAST AT 10 MPH. CITIES IN THE PATH OF THESE STORMS INCLUDE ADDISON...CARROLLTON... COCKRELL HILL...COPPELL...DALLAS...DUNCANVILLE...FARMERS BRANCH... GRAND PRAIRIE...HIGHLAND PARK...HUTCHINS...IRVING...RICHARDSON AND UNIVERSITY PARK. VERY HEAVY RAIN AND WIND GUSTS TO 40 MPH ARE LIKELY WITH THESE STORMS. HEAVY RAINFALL MAY RESULT IN FLOODING OF LOW LYING AREAS SUCH AS DITCHES AND UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY MAY BE WASHED OUT. LAT...LON 3299 9666 3263 9670 3262 9704 3299 9703 TIME...MOT...LOC 1216Z 260DEG 9KT 3295 9694 3269 9698 82/JLD
The Dallas/Ft Worth radar (KFWS), 59 km away, was scanning. The volume nearest the first event began at 15:39 UTC.
1 flash flood. Local standard time, as filed.
The right lane of I35E in Lewisville was closed due to water on the roadway.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Texas in 2014Every state in 2014This day in weather historyWarnings in Texas, August 2014
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 540091.