The Vista fire started around 1052 PST on the 20th, along Vista Road at Rawson Road in Winchester in Riverside County. No evacuations were needed and no structures were threatened or destroyed.
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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 SGX wrote it up.
The Vista fire started around 1052 PST on the 20th, along Vista Road at Rawson Road in Winchester in Riverside County. No evacuations were needed and no structures were threatened or destroyed. Two firefighters received minor injuries. The fire burned a total of 500 acres before being fully controlled around 1900 PST on the 20th (same day). The cause of the fire was determined to be a flare used to kill small animals, called a Gopher Gasser.
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 San Diego, CA wrote its last area forecast discussion before the first event at Aug 20, 8:30 AM PST, 2 hours 22 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN DIEGO CA 930 AM PDT MON AUG 20 2012 .SYNOPSIS... RESIDUAL MONSOONAL MOISTURE WILL CONTINUE A SLIGHT CHANCE OF AFTERNOON AND EARLY EVENING THUNDERSTORMS IN THE MOUNTAINS AND DESERTS THROUGH TUESDAY. A WEAK TROUGH OF LOW PRESSURE WILL DEVELOP OFF THE CALIFORNIA COAST...THEN MOVE SLOWLY INLAND THE LATTER HALF OF THE WEEK. THE INCREASING SOUTHWEST WINDS ALOFT WILL DIMINISH THE THREAT OF THUNDERSTORMS AND ALSO CAUSE THE MARINE LAYER TO GRADUALLY RETURN AND DEEPEN. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... .TODAY... THIS MORNINGS 12Z STANDARD LEVEL ANALYSES BETWEEN 200 AND 700 MB SHOW THE RIDGE AXIS EITHER ALONG OR JUST SOUTH OF THE CA/MEX BORDER WHICH SHOULD BLOCK CONVECTION OVER SONORA MEXICO AND CENTRAL BAJA CALIFORNIA FROM MOVING OVER REGION TODAY. SURFACE OBSERVATION 24 HOUR TRENDS IN DEW POINTS ARE 3 TO 15 DEGREES LOWER. THE 12Z MORNING SOUNDINGS AS WELL THE POINT SOUNDINGS FROM RAP13 SHOW ONE OR MORE STABLE LAYERS BETWEEN 15000-25000 FT MSL AND VEERING WINDS WITH HEIGHT. WATER VAPOR IMAGERY ALSO INDICATES GENERAL SUBSIDENCE ACROSS SOUTHERN CALIFORNIA. UPDATED GRIDS AND FORECASTS TO REFLECT LOWER CHANCE OF THUNDERSTORMS TODAY. .TONIGHT/TUESDAY...THE TROUGH OFF THE WEST COAST MOVES INLAND ACROSS NORTHERN CALIFORNIA WITH TAIL END HANGING BACK OFF THE CENTRAL CALIFORNIA COAST...AND AN EASTERLY WAVE MOVES ACROSS THE SOUTHERN HALF OF BAJA CALIFORNIA DURING THIS TIME PERIOD. THE COMBINED EFFECT IS AN EROSION OF THE MID AND UPPER LEVEL RIDGE ACROSS SOUTHERN CALIFORNIA/NORTHERN BAJA CALIFORNIA. WITH SEVERAL DEGREES OF COOLING FORECAST IN THE 300-500 MB LAYER...AND A PREVAILING SOUTH TO SOUTHEAST FLOW IN THE 850-500 MB LAYER...A MORE MOIST AND UNSTABLE AIR MASS SHOULD BE THE RESULT ACROSS THE MOUNTAINS AND LOWER DESERTS OF SW CALIFORNIA ON TUESDAY. PRECIPITABLE WATER VALUES ARE BACK UP TO +2 INCHES OVER LOWER DESERTS AND 1.5 OR HIGHER OVER MOUNTAINS. THE CURRENT SKY/POP/WX GRIDS LOOK GOOD...MAX TEMP GRIDS WEST OF MOUNTAINS CURRENTLY SHOW ABOUT 5 DEGREES COOLING...MIGHT BE A BIT TOO MUCH FOR INLAND VALLEYS...ASSUMING MARINE AIR DOES NOT PENETRATE THAT FAR INLAND OR DEBRIS CLOUDS FROM NOCTURNAL CONVECTION UPSTREAM ARE NOT PRESENT THROUGH THE MORNING HOURS. TUESDAY NIGHT THROUGH THURSDAY...THE MODELS ARE IN GOOD AGREEMENT IN SPINNING UP THE TAIL END OF THE ABOVE MENTIONED TROUGH INTO A CLOSED LOW AND MOVING IT EAST ALONG A SAN LUIS OBISPO TO LAS VEGAS LINE DURING THIS PERIOD. THIS RESULTS IN AN INCREASE IN THE SOUTHWEST TO WEST FLOW IN THE MID AND UPPER LEVELS ACROSS THE FORECAST AREAS WHICH WOULD LOWER IF NOT END THE THREAT OF THUNDERSTORMS AND PUSH MOST OF THE MONSOON MOISTURE EAST OF THE AREA. THE LOWER 1000-500 MB THICKNESS VALUES ALONG WITH A DEEPER MARINE LAYER DUE TO STRONGER ONSHORE FLOW AND WEAK CYCLONIC FLOW ALOFT WILL ALSO BRING SEVERAL DEGREES COOLING TO ALL AREAS. THE CURRENT GRIDS WILL NEED ADJUSTMENT TO REFLECT THESE TRENDS. THURSDAY NIGHT THROUGH SATURDAY...HIGH PRESSURE ALOFT REBUILDS OVER SOUTHERN CALIFORNIA...EXPECT SEVERAL DEGREES OF WARMING INLAND...A LOWERING OF THE MARINE LAYER...AND NO MONSOON MOISTURE. SUNDAY/MONDAY...LONG WAVE TROUGH DEVELOPS OFF THE WEST COAST AND MOVES INLAND ACROSS NORTHERN CALIFORNIA...SLIGHT COOLING TREND AND INCREASING SOUTHWEST WINDS ACROSS MOUNTAINS AND DESERTS... REDEEPEN THE MARINE LAYER AND CAUSE A LITTLE FURTHER INLAND PENETRATION OF LATE NIGHT/EARLY MORNING CLOUDS. && .AVIATION... 201530Z...COAST/VALLEYS...VFR CONDS WILL CONTINUE THROUGH THIS EVENING. PATCHY STRATUS...WITH BASES AROUND 1100 FT MSL AND TOPS NEAR 1500 FT MSL...IS FORECAST TO DEVELOP ALONG THE COAST BTWN 04-10Z TONIGHT...AND PUSH 10-15 SM INLAND BY MID TUE MORNING. VIS OF 4-6 SM BR IS POSSIBLE OVER HIGHER TERRAIN AND COASTAL MESA TAF SITES. STRATUS AND LOWERED VIS WILL CLEAR TO THE COAST BY 16Z TUE MORNING. MOUNTAINS/DESERTS...CLEAR SKIES WITH UNRESTRICTED VIS TIL 19Z THIS AFTN...THEN SCT-BKN CLOUDS LAYERED FROM 10K FT TO 40K FT WITH ISOLATED SHOWERS AND TSTMS FORECAST THROUGH 01Z TUE. SHOWERS AND TSTMS MAY PRODUCE STRONG UP/DOWNDRAFTS...GUSTY SURFACE WINDS AND LOWERED VIS. CLEARING SKIES WITH UNRESTRICTED VIS AFTER 01Z TUE FOR THE REMAINDER OF THE TAF PERIOD. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && PUBLIC/FIRE WEATHER...BALFOUR AVIATION/MARINE...JJT
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SAN DIEGO CA 800 AM PDT MON AUG 20 2012 CAZ055-056-058-060>062-210200- SAN BERNARDINO COUNTY MOUNTAINS-RIVERSIDE COUNTY MOUNTAINS- SAN DIEGO COUNTY MOUNTAINS-APPLE AND LUCERNE VALLEYS- COACHELLA VALLEY-SAN DIEGO COUNTY DESERTS- 800 AM PDT MON AUG 20 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EXTREME SOUTHWESTERN CALIFORNIA. .DAY ONE...TODAY AND TONIGHT ISOLATED LATE MORNING THROUGH EARLY EVENING THUNDERSTORMS. FOR THE MOUNTAINS...THE FLASH FLOOD POTENTIAL INDEX IS LOW TO MODERATE. FOR THE DESERTS...THE FLASH FLOOD POTENTIAL INDEX IS LOW. THE RISK OF FLASH FLOODING IS MINIMAL. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY FOR TUESDAY...SCATTERED LATE MORNING THROUGH EARLY EVENING THUNDERSTORMS. THE FLASH FLOOD POTENTIAL INDEX IS MODERATE OVER THE MOUNTAINS AND LOW TO MODERATE OVER THE DESERTS. ISOLATED FLASH FLOODING IS POSSIBLE. .SPOTTER INFORMATION STATEMENT... SKYWARN WEATHER ACTIVATION IS NOT REQUESTED FOR THIS AREA... HOWEVER WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS. CAZ042-043-048-050-057-210200- ORANGE COUNTY COASTAL AREAS-SAN DIEGO COUNTY COASTAL AREAS- SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE- SAN DIEGO COUNTY VALLEYS-SANTA ANA MOUNTAINS AND FOOTHILLS- 538 AM PDT MON AUG 20 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EXTREME SOUTHWESTERN CALIFORNIA. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY. 17/BALFOUR
The national radar mosaic for the moment the first event began.
1 wildfire. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2012Every state in 2012This day in weather historyWarnings in California, August 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: 407808.