Severe thunderstorms moved through parts of Southwest Idaho on the 23th producing damaging winds.
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.
Severe thunderstorms moved through parts of Southwest Idaho on the 23th producing damaging winds.
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 Apr 23, 7:54 PM MST, 41 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BOISE ID 854 PM MDT MON APR 23 2012 .DISCUSSION...THUNDERSTORMS DYING DOWN AT SUNSET. STORMS WERE AT MAXIMUM STRENGTH AND COVERAGE AROUND 00Z WHEN THEY EXTENDED FROM SRN MALHEUR COUNTY INTO SWRN IDAHO. STORMS MOVED NNE AND THOSE IN IDAHO HAD MUCH MORE LIGHTNING THAN THE ONES IN OREGON...THAT IS UNTIL AROUND 02Z WHEN VERY ACTIVE STORMS DEVELOPED ALONG THE HARNEY/ MALHEUR COUNTY LINE. AIR MASS WAS MOST UNSTABLE IN NRN ZONES AND WE EXPECTED THAT STORMS WOULD STAY ACTIVE INTO LATE EVENING BUT THEY HAVE NOT. TUESDAY WX SHOULD BE ALMOST A REPEAT OF TODAY BUT NOT QUITE AS WARM OR UNSTABLE. STEADY COOLING THE REST OF THE WEEK WITH LATEST PROGS SHOWING A COLD FRONT AND SHOWERS THURSDAY MORNING ...WRONG TIME OF DAY FOR A CONVECTIVE EVENT IN OREGON AND WRN IDAHO...BUT POSSIBLY IN CENTRAL IDAHO THURSDAY AFTERNOON. ALSO... TURNING COLD ENOUGH FOR SNOW IN THE HIGHER MOUNTAINS THURSDAY...AND AS LOW AS 5000 FEET IN NRN ZONES ON FRIDAY. CURRENT FORECAST LOOKS GOOD...NO UPDATES PLANNED THE REST OF THIS EVENING. && .AVIATION...TONIGHT THROUGH TUESDAY MORNING SCATTERED THUNDERSTORMS WILL CONTINUE OVER NORTHERN HARNEY...NORTHERN MALHEUR...AND BAKER COUNTIES IN OREGON...AND THE CENTRAL IDAHO MOUNTAINS. TUESDAY AFTERNOON EXPECT ISOLATED THUNDERSTORMS OVER MOST OF SOUTHEAST OREGON AND SOUTHWEST IDAHO. SURFACE WINDS WILL BE LIGHT EXCEPT FOR LOCAL GUSTS TO AROUND 40 KTS NEAR THUNDERSTORMS THIS EVENING. WINDS ALOFT WILL BE FROM THE SOUTH UP TO 15 KTS AT 10K FEET MSL. && .HYDROLOGY...SNOWMELT HAS KICKED INTO HIGH GEAR THE PAST COUPLE DAYS WITH RECORD WARMTH SUPPORTING COLD AND SWIFT FLOWS AND SHARP RISES ON MANY RIVERS AND CREEKS. SOME SMALL CREEKS IN BASINS WITH ABUNDANT SNOWPACK MAY REACH BANKFULL WITH POTENTIAL FOR MINOR FLOODING OF ADJACENT LOWLANDS. THE MAIN CONCERN IS FOR LATER THIS WEEK WHEN AN UNSETTLED WEATHER PATTERN DEVELOPS. ALTHOUGH THE TREND WILL BE FOR GRADUAL COOLING THROUGH THE WEEK...TEMPERATURES WILL REMAIN PLENTY WARM FOR SIGNIFICANT SNOWMELT. MEANWHILE...MOISTURE WILL BE ON THE INCREASE WITH THE POTENTIAL FOR WIDESPREAD 1.0 TO 1.5 INCHES OF RAINFALL ACROSS THE WEST CENTRAL AND BOISE MOUNTAINS WEDNESDAY NIGHT THROUGH THURSDAY NIGHT. SNOWMELT COMBINED WITH RAINFALL MAY PUSH SOME OF THE MAINSTEM RIVERS IN THESE AREAS TO BANKFULL BEFORE THE WEEKEND... ESPECIALLY THE PAYETTE RIVER. SMALLER TRIBUTARY RIVERS AND CREEKS WILL NEED TO BE MONITORED THROUGH THE WEEK AS WELL WITH POTENTIAL FOR LOCALLY HEAVY DOWNPOURS ADDING TO THE RUNOFF. && .PREV DISCUSSION... SHORT TERM...TONIGHT THROUGH WEDNESDAY...AT 2 PM MDT - A STRONG RIDGE OF HIGH PRESSURE CONTINUED TO DOMINATE THE ENTIRE WESTERN CONUS. EASTERN OREGON AND SOUTHWEST IDAHO REMAINED UNDER SOUTHWESTERLY FLOW ALOFT...JUST WEST OF THE UPPER RIDGE AXIS. UNSEASONABLY WARM TEMPERATURES AND STEEP LAPSE RATES WERE COMBINING WITH LINGERING MOISTURE TO SPUR AFTERNOON CONVECTION. MEANWHILE... TWO MINOR SHORTWAVES ARE EXPECTED TO MOVE NORTH INTO THE FORECAST AREA BY LATE THIS AFTERNOON...ENHANCING CONVECTION ACROSS SOUTHEAST OREGON AND SOUTH-CENTRAL IDAHO THROUGH THE EVENING HOURS. STRONGEST WIND SHEAR VALUES WILL REMAIN WELL TO OUR WEST...AND ORGANIZED CONVECTION IS NOT EXPECTED AT THIS TIME. THE MAIN OVERALL CONVECTIVE CONCERN LOOKS TO BE WIND...WITH INVERTED-V PROFILES MORE TYPICAL OF THE SUMMER MONTHS. MOST RECENT MODEL DEPICTIONS SHOW TODAY/S CONVECTION PERSISTING THROUGH LATE TONIGHT...THEN REDEVELOPING IN A SIMILAR MANNER TUESDAY AFTERNOON. ON WEDNESDAY...EXPECT INCREASED CHANCES OF PRECIPITATION AND FALLING HEIGHTS/TEMPERATURES AS A DEEP UPPER LOW APPROACHES THE PACIFIC NORTHWEST. LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...SPLIT UPPER TROUGH MOVING ON SHORE WEDNESDAY AND THROUGH THE INTERMOUNTAIN WEST THURSDAY FOR MORE SHOWERS AND THUNDERSTORMS. BEST CHANCE FOR THUNDERSTORMS WILL BE WEDNESDAY NIGHT WITH DECENT SHEAR AND INSTABILITY ACROSS THE AREA. EXPECT WIDESPREAD RAIN SHOWERS ON THURSDAY WITH PASSAGE OF THE TROUGH/COLD FRONT. CONVECTION WILL BE LIMITED WITH COOLING TEMPERATURES AND CLOUD COVER. TEMPERATURES WILL FALL BELOW NORMAL BY FRIDAY. MOIST ZONAL FLOW SETS UP SATURDAY THROUGH EARLY NEXT WEEK FOR NEAR NORMAL TEMPERATURES AND CHANCES FOR SHOWERS EVERY DAY. && .BOI WATCHES/WARNINGS/ADVISORIES... ID...NONE. OR...NONE. && WEATHER.GOV/BOISE DISCUSSION...LC AVIATION.....JT PREV SHORT TERM...MT PREV LONG TERM....JDS/BB HYDROLOGY...TL
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE BOISE ID 1050 AM MDT MON APR 23 2012 IDZ011>016-028>030-033-ORZ061>064-241200- 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- UPPER WEISER RIVER-HARNEY COUNTY-BAKER COUNTY-MALHEUR COUNTY- LOWER TREASURE VALLEY OR- 1050 AM MDT MON APR 23 2012 /950 AM PDT MON APR 23 2012/ 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 THE POTENTIAL EXISTS FOR STRONG THUNDERSTORMS STARTING THIS AFTERNOON AND LASTING THROUGH THE NIGHT. THE MAIN THREAT FROM THESE STORMS WILL BE STRONG WINDS AT THE SURFACE...WITH GUSTS UP TO 50 MPH. WELL ABOVE NORMAL TEMPERATURES WILL INCREASE MOUNTAIN SNOWMELT AND CAUSE SHARP RISES ON MANY WATERWAYS. CREEKS...STREAMS...AND RIVERS WILL BE RUNNING DANGEROUSLY SWIFT AND COLD. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY SNOWMELT WILL CONTINUE TO CAUSE CREEKS...STREAMS...AND RIVERS TO RUN SWIFT AND COLD. SMALLER CREEKS AND STREAMS IN MOUNTAIN AREAS MAY APPROACH BANKFULL. .SPOTTER INFORMATION STATEMENT...
The Boise radar (KCBX), 103 km away, was scanning. The volume nearest the first event began at 03:36 UTC.
1 thunderstorm wind. Local standard time, as filed.
Wind damage including large tree limbs and power lines down was reported by a county official.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2012Every state in 2012This day in weather historyWarnings in Idaho, April 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: 380126.