Moisture (precipitable water near 1 inch) moving north from southern California and Nevada combined with daytime heating to produce afternoon and evening thunderstorms with heavy rain on the 23rd.
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 REV wrote it up.
Moisture (precipitable water near 1 inch) moving north from southern California and Nevada combined with daytime heating to produce afternoon and evening thunderstorms with heavy rain on the 23rd.
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 Reno, NV wrote its last area forecast discussion before the first event at Jul 23, 9:45 AM PST, 3 hours 55 minutes earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE RENO NV 1045 AM PDT MON JUL 23 2012 .UPDATE... MAX TEMPS WILL BE LOWERED ACROSS THE BOARD BY 5 DEGREES TODAY. SHOWERS AND THUNDERSTORMS WILL CONTINUE TO REDEVELOP THROUGH THIS AFTERNOON WITH CLOUD COVERAGE LIMITING HEATING. EVEN THOUGH THERE WILL BE SOME BREAKS IN CLOUD COVER, LOW CONVECTIVE TEMPS OF LOWER 80S WILL LIMIT THE DURATION OF THE SUNNY PERIODS. FORECAST 700 MB TEMPS BETWEEN 11-12 C THIS AFTERNOON WOULD ONLY SUPPORT LOWER 90S FOR MAX TEMPS IN RENO, BUT EVEN THAT TEMPERATURE WILL BE DIFFICULT EXCEPT FOR A BRIEF MOMENT BETWEEN CELLS. MJD && .PREVIOUS DISCUSSION... /ISSUED 328 AM PDT MON JUL 23 2012/ SHORT TERM... QUICK MOVING THUNDERSTORMS DEVELOPED ACROSS THE SIERRA AND WESTERN NEVADA EARLY THIS MORNING AND CONTINUED TO DEVELOP WITH DYNAMIC LIFT IN PLACE FROM THE SHORTWAVE TROUGH. SCATTERED SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH SUNRISE AS THE SHORTWAVE TROUGH PROGRESSES THROUGH NORTHEASTERN CA AND WESTERN NEVADA. RED FLAG WARNINGS ARE CURRENTLY IN EFFECT FOR THE SIERRA FRONT AND THE WEST CENTRAL NEVADA BASIN AND RANGE THROUGH 5AM THIS MORNING. FOR MORE DETAILS ON FIRE WEATHER CONCERNS PLEASE SEE THE FIRE DISCUSSION BELOW. BY THIS AFTERNOON, THE SHORTWAVE TROUGH EXITS THE REGION BUT INSTABILITY FROM SURFACE HEATING AND RESIDUAL MOISTURE WILL KEEP SCATTERED THUNDERSTORMS ACROSS MOST OF THE SIERRA AND WESTERN NEVADA THROUGH THE EARLY EVENING. STORMS THAT MOVED THROUGH THE REGION EARLY THIS MORNING SATURATED THE BOUNDARY LAYER WHICH WILL ALLOW FOR STORMS THIS AFTERNOON TO BE WETTER IN NATURE. WITH PRECIPITABLE WATER VALUES NEARING 1.00 INCH ACROSS THE ENTIRE REGION TODAY, THE MAIN THREATS WITH STORMS TODAY WILL BE: FREQUENT LIGHTNING, LOCALLY HEAVY RAIN, AND SMALL HAIL. STORM MOTIONS WILL REMAIN FAST, SO THE FLASH FLOOD THREAT WILL MINIMIZED, UNLESS STORMS BEGIN TO TRAIN OVER A LOCALIZED AREA. BEGINNING TUESDAY, ATMOSPHERE STABILIZES UNDER SOUTHWEST FLOW AND THE RETURN OF HIGH PRESSURE. SOUNDINGS INDICATE MIDLEVEL CAPPING EACH AFTERNOON, SO LITTLE TO NO CHANCES FOR THUNDERSTORMS TUESDAY AND WEDNESDAY AFTERNOON, WITH ONLY CUMULUS BUILDUPS EXPECTED. LINDAMAN LONG TERM...THURSDAY THROUGH SUNDAY... TROUGH OVER THE PACIFIC NORTHWEST AND RIDGE OF HIGH PRESSURE OVER THE FOUR CORNERS REGION BRINGING GENERALLY DRY SOUTHWEST FLOW AND ABOVE NORMAL TEMPERATURES TO WESTERN NEVADA AND THE SIERRA FOR THE END OF THE WEEK AND INTO THE WEEKEND. MAIN CONCERN FOR THE EXTENDED FORECAST IS THE POSSIBILITY OF THUNDERSTORMS THURSDAY AND FRIDAY. BOTH THURSDAY AND ESPECIALLY FRIDAY HAVE TRENDED DRIER IN THE 00Z RUN OF THE GFS WITH MONSOON MOISTURE NOW STRUGGLING TO MAKE IT INTO WESTERN NEVADA. OPTED TO LEAVE THUNDERSTORMS IN THE FORECAST AT THIS POINT AS AN UPPER LEVEL WAVE IS FORECAST FOR THURSDAY NIGHT, THOUGH THE TIMING OF THE WAVE IS UNCERTAIN. GFS AND ECMWF MODELS CONTINUE TO DIVERGE INTO THE WEEKEND WITH THE ECMWF BRINGING A SHORTWAVE TROUGH INTO NORTHERN CALIFORNIA SUNDAY WHILE THE GFS TROUGH IS MUCH WEAKER AND KEEPS A STRONGER RIDGE OF HIGH PRESSURE OVER THE FOUR CORNERS. THE GFS SOLUTION WOULD ALLOW TEMPERATURES TO CONTINUE TO WARM TO MORE THAN 5 DEGREES ABOVE NORMAL BY THE END OF THE WEEKEND AND BRING TYPICAL AFTERNOON BREEZES TO WESTERN NEVADA. THE ECMWF SOLUTION WOULD KEEP TEMPERATURES CLOSER TO NORMAL WITH STRONGER AFTERNOON BREEZES SUNDAY IN NORTHERN NEVADA. WITH BETTER RUN TO RUN CONSISTENCY HAVE KEPT FORECAST CLOSER TO THE GFS FOR NOW. TOLBY AVIATION... SCATTERED THUNDERSTORMS WILL AFFECT THE SIERRA AND WESTERN NEVADA THROUGH THE AFTERNOON. AS FOR KTRK, KTVL, KRNO, EXPECT PERIODS OF THUNDERSTORMS THROUGH THE DAY, WITH SHORT DURATIONS OF GUSTY OUTFLOW WINDS, HEAVY RAIN AND MVFR CIG CONDITIONS. THUNDERSTORMS WILL TRANSITION AWAY FROM THE SIERRA IN THE LATE AFTERNOON, PUSHING FURTHER INTO WESTERN NEVADA TOWARD KLOL AND KNFL AFTER 00Z. HOON FIRE WEATHER... SHORTWAVE TROUGH CONTINUES TO MOVE ACROSS NORTHERN CALIFORNIA THIS MORNING, WITH NUMEROUS THUNDERSTORMS IN THE SIERRA OVERNIGHT. AIRMASS HAS MOISTENED SIGNIFICANTLY SINCE YESTERDAY'S HYBRID WET/DRY THUNDERSTORM EVENT. BLENDED TPW IS NOW SHOWING PWATS OVER THE SIERRA AND WESTERN NEVADA NEAR 1.0", WITH SURFACE DEWPOINTS IN THE 50S. STORM MOTIONS WILL REMAIN FAST TODAY, 20-30 MPH, ALTHOUGH WITH THE DEEPER MOISTURE THE THREAT FOR DRY LIGHTNING IS REDUCED TODAY. GUSTY OUTFLOW WINDS WILL BE LIKELY TODAY AROUND THUNDERSTORMS AS WELL. RED FLAG WARNINGS WILL BE ALLOWED TO EXPIRE AT 5 AM THIS MORNING. SCATTERED SHOWERS AND THUNDERSTORMS HAVE DEVELOPED OVERNIGHT OVER THE SIERRA AND ALONG THE SIERRA FRONT. THESE THUNDERSTORMS ARE PRODUCING FREQUENT LIGHTNING AND MODERATE AMOUNTS OF RAINFALL. A THUNDERSTORM THAT MOVED OVER DONNER LAKE AROUND 2AM PRODUCED 0.25-0.33" OF RAINFALL ACCORDING TO RAIN GAUGES IN THAT AREA. FLASH FLOOD POTENTIAL WILL BE LOW TODAY, DUE TO FAST STORM MOTIONS. BUT IF NUMEROUS THUNDERSTORMS MOVE OVER A PARTICULAR AREA, LOCALIZED FLASH FLOODING COULD BE POSSIBLE. WE HAVE INCREASED THUNDERSTORM COVERAGE TO SCATTERED ACROSS MOST OF THE FORECAST AREA TODAY, WITH LAL 4. ALSO PUT IN SOME HIGHER CHANCE OF WETTING RAIN (>0.10"), AROUND 20-30%. THERE REMAINS A SMALL THREAT FOR NEW FIRES TODAY, EVEN WITH THE INCREASED MOISTURE. THE AREA OF GREATEST THREAT FOR NEW FIRES WILL BE NORTH OF SUSANVILLE- GERLACH, WHERE A DRIER AIRMASS STILL EXISTS. BUT EVEN THERE, THE PWAT WILL BE APPROACHING 0.8" BY THIS AFTERNOON. NO RED FLAG WARNINGS ARE EXPECTED AT THIS TIME. HOON && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RENO NV 1141 AM PDT MON JUL 23 2012 NVZ001-231915- MINERAL AND SOUTHERN LYON COUNTIES- 1141 AM PDT MON JUL 23 2012 ...THUNDERSTORM WITH HEAVY RAIN APPROACHING LUNING IN MINERAL COUNTY... AT 1131 AM PDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING A STRONG THUNDERSTORM 10 MILES SOUTHWEST OF LUNING...MOVING NORTHEAST AT 25 MPH. OCCASIONAL LIGHTNING...BRIEF HEAVY RAINFALL AND SMALL PEA SIZE HAIL WILL OCCUR WITH THIS STORM. * LOCATIONS AFFECTED INCLUDE...LUNING AND MOUNT FERGUSON. DURING A THUNDERSTORM...SEEK SHELTER INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS. MOTORISTS ON HIGHWAY 95 BETWEEN MINA AND HAWTHORNE CAN EXPECT WET ROAD SURFACES AND REDUCED VISIBILITY THROUGH 1215 PM. && LAT...LON 3879 11812 3863 11788 3829 11829 3841 11847 TIME...MOT...LOC 1834Z 220DEG 20KT 3842 11830 MJD
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RENO NV
147 PM PDT MON JUL 23 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0147 PM HAIL 1 NW SIERRAVILLE 39.60N 120.38W
07/23/2012 M0.50 INCH SIERRA CA TRAINED SPOTTER
TRAINED WEATHER SPOTTER REPORTED 3/8THS TO 1/2 INCH HAIL
ALONG WITH HEAVY RAINFALL. SPOTTER REPORTED 0.27 INCHES
OF RAINFALL IN ROUGHLY 15 MINUTES. SPOTTERS TOTAL
RAINFALL SINCE MIDNIGHT IS 0.87 INCHES.
&&
MCGUIRESPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE RENO NV
157 PM PDT MON JUL 23 2012
CAZ071-232145-
LASSEN-EASTERN PLUMAS-EASTERN SIERRA COUNTIES-
157 PM PDT MON JUL 23 2012
...THUNDERSTORMS WITH HEAVY RAINFALL AND SMALL HAIL MOVING ACROSS
THE SIERRA VALLEY...
AT 145 PM PDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING
SEVERAL STRONG THUNDERSTORMS IN THE SIERRA VALLEY NORTH OF TRUCKEE
TO SIERRAVILLE TO LAKE DAVIS...MOVING NORTH NORTHEAST AT 25 MPH.
OCCASIONAL LIGHTNING...HEAVY RAINFALL...AND SMALL PEA SIZE HAIL
WILL OCCUR WITH THESE STORMS.
* LOCATIONS AFFECTED INCLUDE...SIERRAVILLE...PORTOLA...LOYALTON...
BECKWOURTH...CALPINE...CHILCOOT...FRENCHMAN LAKE...HALLELUJAH
JUNCTION AND LAKE DAVIS.
THESE STORMS WILL AFFECT TRAVELERS ON HIGHWAY 89 BETWEEN TRUCKEE AND
GRAEAGLE...HIGHWAY 49 THROUGH THE SIERRA VALLEY...HIGHWAY 70 THROUGH
EASTERN PLUMAS COUNTY...AND HIGHWAY 395 BETWEEN SUSANVILLE AND
HALLELUJAH JUNCTION THROUGH 245 PM. DRIVERS ON THESE HIGHWAYS CAN
EXPECT REDUCED VISIBILITY...LOCALLY HEAVY RAINFALL AND PONDING OF
WATER. SLOW DOWN WHEN ENCOUNTERING HEAVY RAIN AND TURN ON YOUR
HEADLIGHTS.
&&
LAT...LON 4020 12049 4004 12035 3986 12002 3944 12015
3943 12038 3948 12045 3960 12047 3966 12058
3987 12061
TIME...MOT...LOC 2047Z 194DEG 23KT 3987 12056 3954 12052
3939 12025
MJDSPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RENO NV 158 PM PDT MON JUL 23 2012 NVZ001-232145- MINERAL AND SOUTHERN LYON COUNTIES- 158 PM PDT MON JUL 23 2012 ...STRONG THUNDERSTORM LIFTING NORTHEAST ACROSS MINERAL COUNTY... AT 148 PM PDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING A STRONG THUNDERSTORM 20 MILES SOUTHWEST OF MINA...OR 25 MILES NORTH OF BENTON...AND MOVING NORTHEAST AT 25 MPH. FREQUENT DEADLY LIGHTNING...MODERATE TO HEAVY RAIN...AND SMALL PEA SIZE HAIL...ARE LIKELY WITH THIS STORM. THE RAINS MAY CAUSE PONDING OF WATER ON HIGHWAY 95 BETWEEN MINA AND TONOPAH JUNCTION. * LOCATIONS AFFECTED INCLUDE...MINA AND TONOPAH JUNCTION. && LAT...LON 3857 11812 3842 11787 3806 11827 3816 11845 TIME...MOT...LOC 2054Z 217DEG 21KT 3818 11829
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE RENO NV
222 PM PDT MON JUL 23 2012
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0222 PM LIGHTNING SUTCLIFFE 39.95N 119.60W
07/23/2012 WASHOE NV TRAINED SPOTTER
TRAINED WEATHER SPOTTER REPORTED FREQUENT LIGHTNING AND
BLOWING DUST.
&&
MCGUIRESPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE RENO NV 222 PM PDT MON JUL 23 2012 NVZ003-004-232245- GREATER RENO-CARSON CITY-MINDEN AREA-WESTERN NEVADA BASIN AND RANGE INCLUDING PYRAMID LAKE- 222 PM PDT MON JUL 23 2012 ...THUNDERSTORMS APPROACHING PYRAMID LAKE... AT 215 PM PDT...NATIONAL WEATHER SERVICE METEOROLOGISTS WERE TRACKING A STRONG THUNDERSTORM NEAR SUTCLIFFE...OR 10 MILES SOUTH OF PYRAMID LAKE...AND MOVING NORTHEAST AT 25 MPH. FREQUENT DEADLY LIGHTNING...MODERATE TO HEAVY RAIN...AND SMALL PEA SIZE HAIL...ARE LIKELY WITH THIS STORM. ADDITIONAL THUNDERSTORMS ARE POSSIBLE IN THE PYRAMID LAKE REGION THROUGH 4 PM. * LOCATIONS AFFECTED INCLUDE...PYRAMID LAKE...SUTCLIFFE AND THE NEEDLE ROCKS. IF ON OR NEAR A LAKE...GET OUT OF THE WATER AND MOVE INDOORS OR INSIDE A VEHICLE NOW. DON'T BE CAUGHT ON THE WATER IN A THUNDERSTORM. STRONG WIND GUSTS AND LIGHTNING POSE AN IMMEDIATE DANGER TO BOATERS. GUSTY WINDS WILL CAUSE A RAPID INCREASE IN WAVE HEIGHTS WHICH MAY CAPSIZE SMALL BOATS. && LAT...LON 4024 11968 4004 11920 3979 11951 3991 11975 TIME...MOT...LOC 2117Z 216DEG 21KT 3992 11956 MYRICK
The Reno radar (KRGX), 201 km away, was scanning. The volume nearest the first event began at 21:42 UTC.
1 debris flow, 1 flash flood. Local standard time, as filed.
The Mineral County Fire Department reported a debris flow across highway 95 which caused some road damage.
A Reno news station meteorologist and a couple spotters sent several videos of fast flowing water over Nye Road near its intersection with Johnson Lane. The water caused severe damage to Nye Road. The water was also seen flowing down Johnson Lane closer to highway 395. The Douglas County Sheriff reported water flowing over multiple roads in the Minden-Johnson Lane area around 1720PST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Nevada in 2012Every state in 2012This day in weather historyWarnings in Nevada, July 2012
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: 400177, 399641.