An unseasonably deep Pacific trough interacted with monsoon moisture to produce scattered severe thunderstorms and flash flooding across the Mojave Desert.
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 VEF wrote it up.
An unseasonably deep Pacific trough interacted with monsoon moisture to produce scattered severe thunderstorms and flash flooding across the Mojave Desert.
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 Las Vegas, NV wrote its last area forecast discussion before the first event at Aug 7, 8:55 PM PST, 2 hours 35 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LAS VEGAS NV 955 PM PDT SAT AUG 7 2010 .SYNOPSIS...A TROUGH OF LOW PRESSURE ALONG THE WEST COAST WILL INTERACT WITH MONSOON MOISTURE TO PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS OVER SOUTHERN NEVADA AND NORTHWEST ARIZONA THROUGH MONDAY...WITH STORMS ALSO POSSIBLE OVER THE SIERRA NEVADA AND NEARBY MOUNTAIN RANGES SUNDAY. DRIER AIR WILL PUSH IN FROM THE WEST BY MONDAY NIGHT...WITH DRY WEATHER EXPECTED TUESDAY THROUGH FRIDAY. TEMPERATURES WILL BE SLIGHTLY BELOW NORMAL SUNDAY AND MONDAY...THEN RETURN TO ABOVE NORMAL FOR THE REST OF THE UPCOMING WEEK. && .UPDATE...STRONG THUNDERSTORMS DEVELOPED OVER EASTERN SAN BERNARDINO COUNTY AFTER 8 PM AND CONVECTION WAS EXPANDING NORTHWARD. THE 00Z NAM AND GFS PICKED UP ON THE HIGHER MOISTURE AND INSTABILITY ASSOCIATED WITH THIS AREA AND BOTH BRING IT NORTH ACROSS CLARK COUNTY OVERNIGHT. THE INHERITED FORECAST ALREADY INDICATED THE INCREASING CHANCE OF THUNDERSTORMS OVERNIGHT AND THE UPDATED FORECAST WAS MAINLY TWEAKED TO ADD THUNDERSTORM COVERAGE TERMS AND TRIM BACK POPS A LITTLE IN SOUTHEAST MOHAVE COUNTY. NO OTHER SIGNIFICANT CHANGES WERE NEEDED. && .AVIATION...FOR MCCARRAN...GUSTY SOUTH WINDS WILL SUBSIDE BETWEEN 05-06Z THIS EVENING AND REMAIN SOUTHERLY AT 10-14KTS. THERE IS A CHANCE FOR THUNDERSTORMS IN THE VALLEY TONIGHT...BUT WILL KEEP MENTION OF CB IN THE TAF AS MOUNTAIN AREAS AROUND THE VALLEY WILL BE MOST LIKELY TO SEE THEM. WITH THE PEACH SPRINGS AND MORMON MESA CORRIDORS WILL SEE ISOLATED THUNDERSTORMS THROUGHOUT TONIGHT. THE WINDS WILL PICK UP AND GUST AGAIN LATE SUNDAY MORNING FROM THE SOUTH. SUNDAY AFTERNOON AND EVENING WILL SEE THUNDERSTORMS FORM OVER THE AREA AND THERE IS A SLIGHT CHANCE FOR ONE IN THE LAS VEGAS VALLEY. IF ONE DOES NOT MOVE OVER THE TERMINAL THERE IS A CHANCE OUTFLOW WINDS FROM THE STORMS COULD AFFECT THE WIND DIRECTIONS AND SPEEDS AT KLAS. FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST CALIFORNIA...GUSTY SOUTHWEST WINDS WILL GRADUALLY WIND DOWN OVER THE COURSE OF THIS EVENING. THUNDERSTORMS ARE POSSIBLE THROUGH LATE SATURDAY EVENING OVER MOHAVE...LINCOLN...AND CLARK COUNTIES. WINDS WILL BE GUSTY AND ERRATIC IN AND NEAR ANY THUNDERSTORMS OR OUTFLOW BOUNDARIES AND STORMS COULD ALSO RESULT IN REDUCED VSBY. SUNDAY WILL SEE THUNDERSTORMS FORM AGAIN IN THE LATE MORNING THROUGH THE EVENING. THE HIGHEST PROBABILITY AND COVERAGE WILL BE ROUGHLY EAST OF A KDRA-KLAS-KEED LINE. && .PREV DISCUSSION... 301 PM PDT SAT AUG 7 2010 .SHORT TERM...LOW LEVEL MOISTURE HAS MADE GREAT PROGRESS NORTHWEST ACROSS OUR CWFA TODAY...AND SATELLITE SHOWS THUNDERSTORMS TRYING TO DEVELOP IN THE MOIST AIR OVER MOHAVE...CLARK AND LINCOLN COUNTIES. AS OF 230 PM MOST ACTIVITY HAD BEEN IN LINCOLN COUNTY...WITH MOHAVE BEING LARGELY CLOUD FREE APPARENTLY DUE TO ATMOSPHERIC OVERTURNING WITH THE STORMS OVERNIGHT AND EARLY THIS MORNING. ALL THE SUNSHINE WILL HELP DESTABILIZE THE AIRMASS ONCE AGAIN...AND MORE STORMS SHOULD DEVELOP BEFORE SUNSET. NAM AND GFS AGREE TO SOME EXTENT ON STORMS PERSISTING OVERNIGHT AGAIN TONIGHT. TOMORROW IS A GREATER CONCERN. A JET STREAK...YES A JET STREAK IN EARLY AUGUST...ROTATING AROUND THE BASE OF THE WEST COAST TROUGH WILL PASS OVER OUR CWFA DURING THE DAY TOMORROW...AND THE NAM DEPICTS AN AREA OF DIVERGENCE ALOFT ASSOCIATED WITH IT OVER OUR NORTHEAST ZONES. THIS SHOULD HELP FIRE MORE STORMS...AND COULD EVEN LEAD TO SOME ORGANIZATION. RAISED POPS IN THIS AREA. MODELS CONTINUE TO TREND SLOWER WITH THE EASTWARD DEPARTURE OF PRECIP MONDAY AND MONDAY NIGHT...SO SLOWED DOWN THE WEST TO EAST DRYING TREND BY A FEW MORE HOURS. STILL FORECASTING DOUBLE DIGIT HIGH TEMPS FOR KLAS TOMORROW. AS OF 245 PM TODAY...THE HIGH HAS BEEN 98 DEGREES...SO STILL TOO CLOSE TO CALL WHETHER THE 100 DEGREE STREAK WILL REACH 46 DAYS TODAY. .LONG TERM...NO CHANGES WERE MADE TO THE EXTENDED...AS MODELS SHOW DECENT CONTINUITY WITH PREVIOUS RUNS. TUESDAY THROUGH THE END OF THE WEEK..ALL MODELS INDICATE CONTINUED DRY SOUTHWESTERLY FLOW ACROSS THE FORECAST AREA TO ONE DEGREE OR ANOTHER...BUT DIFFERENCES BETWEEN THE EVOLUTION OF THE OFFSHORE LOW PLACES SOME UNCERTAINTY IN TEMPERATURES. IN ANY CASE...PRECIPITATION/CONVECTION LOOKS HIGHLY UNLIKELY. THE GEM/GFS/AND GFS ENSEMBLE MEAN PROG THE LONGWAVE TROUGH CURRENTLY OFFSHORE TO GRADUALLY TRANSITION WESTWARD AS RIDGING BUILDS IN FROM THE SOUTHEAST...CENTERING A STRONG HIGH JUST SOUTH OF THE REGION BY NEXT WEEKEND. THE EC ON THE OTHER HAND SLIDES THE LONGWAVE TROUGH EAST AND OVER THE WESTERN STATES...AS RIDGING BUILDS ACROSS THE EASTERN PACIFIC. THIS STILL RESULTS IN A DRY FORECAST...BUT HEIGHTS/THICKNESS WOULD BE MUCH LOWER...AND CONSEQUENTLY SURFACE TEMPERATURES WOULD BE LOWER AS WELL. HAVE OPTED TO RUN WITH CONSENSUS...WITH A GRADUAL WARMING TREND TO SURFACE TEMPS FORECAST...AND NO PRECIP. && .CLIMATE...THROUGH SATURDAY MORNING...29 DAYS IN A ROW HAVE HAD LOW TEMPERATURES OF 80 DEGREES OR WARMER. THIS IS AN ALL-TIME RECORD...BREAKING THE OLD RECORD OF 24 DAYS FROM JUNE 29TH THROUGH JULY 22ND 2007. THE STREAK OF 45 DAYS IN A ROW WITH A HIGH OF 100 DEGREES OR WARMER ENDED TODAY. THE HIGH TEMPERATURE AT MCCARRAN AIRPORT PEAKED AT 99 DEGREES SATURDAY AFTERNOON. THIS TIED A SIMILAR STREAK IN 1971 FOR THE THIRD LONGEST ON RECORD. THE SECOND LONGEST STREAK WAS 46 DAYS FROM JUNE 20TH THROUGH AUGUST 4TH 1988...AND THE ALL-TIME RECORD IS 66 DAYS WHICH RAN FROM JUNE 27TH THROUGH AUGUST 31ST 1944. && .VEF WATCHES/WARNINGS/ADVISORIES... NV...NONE. AZ...NONE. CA...NONE. && UPDATE...ADAIR AVIATION...JACQUES PREV DISCUSSION...MORGAN/KENNEDY HTTP://WEATHER.GOV/LASVEGAS
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE LAS VEGAS NV 525 AM PDT SAT AUG 7 2010 AZZ002-036-CAZ519>527-NVZ014>022-080330- LOWER COLORADO RIVER VALLEY-LAKE MEAD NATIONAL RECREATION AREA- EASTERN SIERRA SLOPES-OWENS VALLEY-WHITE MOUNTAINS OF INYO COUNTY- DEATH VALLEY NATIONAL PARK-WESTERN MOJAVE DESERT- EASTERN MOJAVE DESERT-MORONGO BASIN-CADIZ BASIN- SAN BERNARDINO COUNTY-UPPER COLORADO RIVER VALLEY- ESMERALDA AND CENTRAL NYE COUNTY-LINCOLN COUNTY- NORTHEAST CLARK COUNTY-WESTERN CLARK AND SOUTHERN NYE COUNTY- SHEEP RANGE-SPRING MOUNTAINS-LAS VEGAS VALLEY- SOUTHERN CLARK COUNTY- 525 AM PDT SAT AUG 7 2010 /525 AM MST SAT AUG 7 2010/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST ARIZONA...CALIFORNIA AND SOUTHERN NEVADA. .DAY ONE...TODAY AND TONIGHT AN AREA OF LOW PRESSURE WILL STRENGTHEN OVER CALIFORNIA BRINGING ISOLATED THUNDERSTORMS TO THE SIERRA. MOISTURE INCREASING FROM THE SOUTH AHEAD OF THE LOW WILL RESULT IN ISOLATED TO SCATTERED THUNDERSTORMS DEVELOPING OVER ACROSS MOHAVE...LINCOLN AND CLARK COUNTIES AND FAR EASTERN PORTIONS OF SAN BERNARDINO COUNTY. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY MOISTURE WILL SPREAD FARTHER WEST BY SUNDAY WITH A CHANCE OF THUNDERSTORMS ACROSS SOUTHERN NEVADA AND NORTHWEST ARIZONA AND ALSO IN THE MOUNTAINS OF NORTHERN INYO COUNTY. A DRY SOUTHWEST FLOW WILL DEVELOP MONDAY AS THE LOW PRESSURE SYSTEM MOVES EAST OF THE AREA. DRY CONDITIONS WILL PERSIST THROUGH FRIDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. HOWEVER, SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ001-003-080330- NORTHWEST PLATEAU-NORTHWEST DESERTS- 525 AM MST SAT AUG 7 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST ARIZONA. .DAY ONE...TODAY AND TONIGHT SHOWERS AND THUNDERSTORMS ARE LIKELY TODAY INTO TONIGHT. THESE STORMS WILL PRODUCE BRIEF HEAVY RAIN AND GUSTY WINDS. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY SCATTERED THUNDERSTORMS WILL CONTINUE SUNDAY INTO SUNDAY NIGHT BUT DRY SOUTHWEST FLOW WILL DEVELOP BY MONDAY AS THE LOW PRESSURE SYSTEM WHICH HAS BEEN OVER CALIFORNIA MOVES EAST OF THE AREA. DRY CONDITIONS WILL PERSIST THROUGH FRIDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED TODAY AND TONIGHT.
The Las Vegas radar (KESX), 78 km away, was scanning. The volume nearest the first event began at 07:30 UTC.
2 flash flood, 1 lightning, 1 thunderstorm wind, 1 hail. Local standard time, as filed.
Eight inches of water and debris flowed across Aha Macav Parkway.
Lightning struck a house, setting it afire.
A spotter estimated wind gusts to 60 mph, along with pea sized hail and very heavy rain.
Large hail dented several cars on Interstate 15. The hail size is an estimate, and may be underestimated considering the nature of damage reported.
Delayed-onset flash flooding caused by heavy rain one to two hours earlier washed out two streets and left at least two others impassable.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Nevada in 2010Every state in 2010This day in weather historyWarnings in Nevada, August 2010
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: 239864, 239866, 239869, 239870, 239873.