A cold front moving through Idaho and the attendant moisture lead to showers and thunderstorms that produced local rainfall amounts of one inch per hour and flash flooding in Southwest Idaho.
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 BOI wrote it up.
A cold front moving through Idaho and the attendant moisture lead to showers and thunderstorms that produced local rainfall amounts of one inch per hour and flash flooding in Southwest Idaho.
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 Boise, ID wrote its last area forecast discussion before the first event at Jun 6, 2:01 PM MST, 4 hours 29 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BOISE ID 301 PM MDT SAT JUN 6 2009 .SHORT TERM...TONIGHT THROUGH MONDAY...A COLD FRONT ACROSS CENTRAL PORTIONS OF OREGON AND IDAHO WAS INITIATING A LINE OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON. MCCALL HAD PICKED UP 0.25 INCHES 203-53PM BUT A RAWS IN FAR NW VALLEY COUNTY AT 4000 FT MSL RECEIVED 0.52/HOUR AS OF 2 PM. LOOK FOR THE HIGHEST POPS ACROSS THE NE 1/4 OF ZONES WITH STRONGEST CELLS CAPABLE OF PUTTING DOWN AN INCH PER HOUR RAINFALL AND HAIL. WIND GUSTS AROUND 35 MPH ARE EXPECTED AS THE ATMOSPHERE IS VERY MOIST. THE FRONT SINKS SLIGHTLY SOUTH BUT SHEARS OUT TO THE ESE AFTER MIDNIGHT AROUND THE VALLEY/BOISE COUNTY LINE. CELLS ALSO POPPING ACROSS OREGON AND S OF THE FRONT BUT MUCH MORE ISOLATED. ACROSS THE SRN MTS SHOWERS HAVE LINGERED ALL DAY IN THE UPSLOPE/NORTH FACING AREA OF THE OWYHEE MOUNTAINS AND SRN TWF COUNTY...LIMITING INSTABILITY - AIDED HEATING. THIS AREA LOOKS TO SINK SOUTH THIS EVENING THEN DECREASE SLOWLY THROUGH SUNDAY MORNING. NORTHWEST FLOW CONTINUES THROUGH MONDAY WITH ENOUGHT MOISTURE MAINLY ACROSS NE ZONES FOR LATE DAY SHOWERS AND POSSIBLE THUNDERSTORMS. TEMPERATURES STAY COOL THROUGH EARLY MONDAY MORNING THEN WARM AROUND 5F FOR MONDAY AFTERNOON. .LONG TERM...MONDAY NIGHT THROUGH SATURDAY...MONDAY NIGHT THROUGH WEDNESDAY MODELS AGREE ON SOME SORT OF WEST COAST TROUGHING WITH MOST OF THE UPPER LEVEL FLOW WELL SOUTH OF US OVER THE SOUTHWEST STATES...AND WEAK DISTURBANCES CROSSING OUR AREA AS THEY MOVE AROUND THE SOUTHWEST PERIPHERY OF A BROAD UPPER LOW CENTERED OVER SOUTH CENTRAL CANADA AND THE NORTHERN PLAINS. MODEL BLENDS KEEP ABOVE NORMAL POPS FOR THIS PERIOD...MAINLY IN THE CHANCE CATEGORY...AND BELOW NORMAL DAYTIME TEMPERATURES. FOR THURSDAY THROUGH SATURDAY THE ECMWF...AND TO A LESSER EXTENT THE GFS...DEVELOP A NEGATIVE TILT UPPER TROUGH NEAR THE WEST COAST. SO FOR THOSE DAYS WE INCREASED POPS TO CHANCE OVER MOST OF THE AREA...WHICH IS CONSIDERABLY ABOVE CLIMATOLOGY FOR THIS TIME OF YEAR. && .AVIATION...AREAS OF MVFR CEILINGS AND MTN OBSCURATION WILL CONTINUE THIS EVENING WITH AREAS OF RAIN SHOWERS AND ISOLATED THUNDERSTORMS UNTIL ABOUT 06Z. AFTER 06Z SCATTERED RAIN SHOWERS WILL PERSIST THROUGH SUNDAY MORNING. SUNDAY AFTERNOON EXPECT IMPROVING MAINLY VFR CONDITIONS WITH ONLY SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THROUGH SUNDAY EVENING. SURFACE WINDS WILL BE LIGHT TONIGHT INCREASING TO NORTHWEST 15-25 KTS SUNDAY. WINDS ALOFT WILL BE NORTHWEST 20-25 KTS AT 10K FT MSL. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...NONE. OR...NONE. && WEATHER.GOV/BOISE SHORT TERM...VM LONG TERM....JT AVIATION.....JT
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE BOISE ID 555 AM MDT SAT JUN 6 2009 IDZ011>016-028>030-ORZ061>064-071200- WEST CENTRAL MOUNTAINS-LOWER TREASURE VALLEY ID-BOISE MOUNTAINS- UPPER TREASURE VALLEY-SOUTHWEST HIGHLANDS-WESTERN MAGIC VALLEY- CAMAS PRAIRIE-OWYHEE MOUNTAINS-SOUTHERN TWIN FALLS COUNTY- HARNEY COUNTY-BAKER COUNTY-MALHEUR COUNTY- LOWER TREASURE VALLEY OR- 555 AM MDT SAT JUN 6 2009 /455 AM PDT SAT JUN 6 2009/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL IDAHO...SOUTHWEST IDAHO...WEST CENTRAL IDAHO...NORTHEAST OREGON AND SOUTHEAST OREGON. .DAY ONE...TODAY AND TONIGHT NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED.
The Boise radar (KCBX), 59 km away, was scanning. The volume nearest the first event began at 01:30 UTC.
2 flash flood. Local standard time, as filed.
Several homes in Mountain Home, Idaho had water in the basement due to water flowing across the ground from heavy rain.
Flash Flooding was reported by law enforcement along Highway 78 and closed a section from Grandview to Walters Ferry, Idaho. A fatality occured when a vehicle was swept into the Snake River near Murphy, Idaho.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Flash Flood, Owyhee | 2009-06-06 | Male | Vehicle/Towed Trailer | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2009Every state in 2009This day in weather historyWarnings in Idaho, June 2009
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: 179414, 179408.