The Onion Wildfire was started by lightning on 08/19/2011. By the time it was contained around 09/10/2011, it had burned 560 acres.
Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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 MFR wrote it up.
The Onion Wildfire was started by lightning on 08/19/2011. By the time it was contained around 09/10/2011, it had burned 560 acres. No fire fighting cost estimates were available.
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 Medford, OR wrote its last area forecast discussion before the first event at Aug 19, 1:26 PM PST, 4 hours 1 minute earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
226 PM PDT FRI AUG 19 2011
.DISCUSSION...CURRENT VISIBLE IMAGE SHOWS CUMULUS DEVELOPING ALONG
THE CASCADES AND HIGHER TERRAIN IN SISKIYOU...LAKE AND KLAMATH COUNTY
WHICH IS SIMILAR TO YESTERDAY AT THIS TIME. ALSO MARINE STRATUS IS
MOVING SOUTH ALONG THE COAST. THE WATER VAPOR IMAGE SHOWS A WEAK
TROF MOVING INTO SOUTHWEST OREGON.
THE MODELS SUGGEST THE TROF WILL SLOWLY MOVE SOUTH AND EVOLVE INTO A
WEAK UPPER LOW IN NORTHWEST CALIFORNIA. THIS WILL BRING A WEAK SOUTH
TO SOUTHEAST FLOW ALONG WITH INCREASING MID LEVEL MOISTURE AND WEAK
PVA. HOWEVER MODEL SOUNDING SUGGEST THERE WILL BE A CAP SATURDAY
AFTERNOON WHICH WILL WORK AGAINST STORM DEVELOPMENT. HOWEVER THERE
STILL BE BE SUFFICIENT INSTABILITY FOR ISOLATED STORMS TO DEVELOP
INITIALLY OVER THE HIGHER TERRAIN. WHILE 700 MB WINDS ARE PROJECTED
TO BE LIGHT...THERE IS A SOUTHEASTERLY COMPONENT WHICH MEANS THAT
ANY ISOLATED STORMS THAT DEVELOP OVER THE HIGHER TERRAIN COULD DRIFT
INTO THE SOUTHERN END OF THE ROGUE VALLEY. KEEP IN MIND THIS THERE
IS STILL SOME UNCERTAINTY AND THIS ASSUMES THAT ISOLATED STORMS DO
DEVELOP.
THE WEAK UPPER LOW LINGERS IN NORTHWEST CALIFORNIA INTO SUNDAY.
HOWEVER INSTABILITY PW VALUES ARE EXPECTED TO INCREASE. ALSO THERE
SHOULD BE MORE MOISTURE AT THE MID LEVELS WITH A WEAK SOUTHEAST
FLOW. THIS COULD FORE UP MORE STORM ACTIVITY...BUT STILL EXPECT THEM
TO BE ISOLATED.
THE EC AND GFS SUGGEST A WESTERLY FLOW DEVELOPS OVER PART OF THE CWA
MONDAY. THIS SHOULD LESSEN THE CHANCE FOR ISOLATED STORMS TO
DEVELOP. THE GFS SHOWS SOME WEAK PVA AND INSTABILITY EAST OF THE
CASCADES IN THE AFTERNOON...SO HAVE KEPT A SLIGHT CHANCE MAINLY IN
LAKE COUNTY AND EASTERN KLAMATH AND SISKIYOU COUNTY.
TUESDAY...THE EC SHOWS 500 MB HEIGHT RISES WITH A RIDGE NOSING INTO
SOUTHWEST REGION. IN CONTRAST...THE GFS SHOWS THE WEAK TROF IN
NORTHERN CAL WHICH IF CORRECT WOULD BRING A CHANCE FOR ISOLATED
STORMS IN NORTHERN CALIFORNIA. GIVEN THE UNCERTAINTY BETWEEN THE
MODELS AND INCONSISTENT FROM ONE RUN TO THE NEXT...DID NOT MAKE ANY
CHANGES TO TUESDAY'S FORECAST.
BEYOND TUESDAY...THE PICTURE IS MUCH LESS CLEAR. THE EC AND GFS
CONTINUE TO BE AT ODDS WITH RESPECT TO THE PATTERN AND HAVE NOT BEEN
CONSISTENT. TAKING THE GFS AT FACE VALUE WOULD RESULT IN THE
POTENTIAL FOR ISOLATED MAYBE SCATTERED STORMS ALONG AND EAST OF THE
CASCADES. ON THE FLIP SIDE...THE EC SUGGEST THE THREAT OF STORMS
WOULD BE MAINLY IN IDAHO AND NOT OREGON. CURRENT FORECAST HAS
ISOLATED STORMS IN THE FORECAST FOR WEDNESDAY AND THURSDAY AFTERNOON
AND EARLY EVENING...BUT CONFIDENCE IS LOW THAT THIS WILL PAN OUT.
-PETRUCELLI
&&
.AVIATION...THE VISIBLE IMAGE SHOWS MARINE STRATUS WORKING IT'S WAY
DOWN THE COAST. THE MARINE STRATUS IS JUST WEST OF KOTH...BUT THERE
IS CONCERN IFR CIGS COULD MOVE IN IN THE NEXT TWO TO THREE HOURS AND
PERSIST INTO TONIGHT. ELSEWHERE VFR CONDITIONS CONTINUE THROUGH
SATURDAY MORNING. INSTABILITY CLOUDS DEVELOP SATURDAY AFTERNOON OVER
THE HIGHER TERRAIN...BUT THE BASES SHOULD REMAIN ABOVE MTN TOPS.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ356.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ356.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 2 AM PDT SATURDAY FOR
PZZ370.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 2 AM PDT SATURDAY
FOR PZZ370.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 5 PM PDT SATURDAY FOR
PZZ376.
HAZARDOUS SEAS WARNING UNTIL 11 PM PDT THIS EVENING FOR PZZ376.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 11 PM PDT THIS EVENING FOR
PZZ350.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 11 PM PDT THIS
EVENING FOR PZZ350.The national radar mosaic for the moment the first event began.
1 wildfire. Local standard time, as filed.
The Onion Wildfire was started by lightning on 08/19/2011. By the time it was contained around 09/10/2011, it had burned 560 acres. No fire fighting cost estimates were available.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2011Every state in 2011This day in weather historyWarnings in California, August 2011
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: 334377.