Nine to 18 inches of snow were widespread at elevations above 7 thousand feet in the Central Mountains.
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 PIH wrote it up.
Nine to 18 inches of snow were widespread at elevations above 7 thousand feet in the Central Mountains.
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 Pocatello, ID wrote its last area forecast discussion before the first event at Nov 20, 2:53 AM MST, 2 hours 7 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE POCATELLO ID 253 AM MST TUE NOV 20 2012 .SHORT TERM...TODAY THROUGH THURSDAY. WE ARE ALREADY SEEING SIGNS OF A STRONG OVERRUNNING/UPSLOPE EVENT ACROSS WESTERN PORTIONS OF OUR FORECAST AREA THIS MORNING. AS OF 230 AM...A BAND OF RAIN AND MOUNTAIN SNOW LIES GENERALLY WEST OF A LINE FROM CITY OF ROCKS TO CHALLIS. MOISTURE AMOUNTS ARE LIGHT THIS MORNING...BUT WILL REALLY CRANK UP THIS MORNING ESPECIALLY ACROSS THE NORTHERN MAGIC VALLEY AND AROUND CRATERS OF THE MOON BACK INTO THE CENTRAL MOUNTAINS. AS WE GO THROUGH THE DAY...THIS SURGE OF MOISTURE WILL SPREAD NORTHEAST ACROSS THE ARCO DESERT AND INTO THE FAR UPPER SNAKE PLAIN AND HIGHLANDS. THE MOISTURE RETREATS BASICALLY INTO THE CENTRAL MOUNTAINS OVERNIGHT...ONLY TO SPREAD BACK SOUTH AND EAST TOMORROW AS THE NEXT WAVE AND ASSOCIATED COLD FRONT SWING ACROSS EASTERN IDAHO. ABOUT THE ONLY PLACE WE WILL NOT SEE A DECENT CHANCE OF MEASURABLE RAIN OR SNOW WITH THIS EVENT IS ALONG THE UTAH BORDER AND AROUND BEAR LAKE. WITH THE STRONG SOUTHWEST FLOW ACROSS THE AREA...THERE WILL BE HUGE DIFFERENCES IN PRECIPITATION AMOUNTS DUE TO UPSLOPE/DOWNSLOPE EFFECTS. THE WESTERN RANGES OF THE CENTRAL MOUNTAINS AND UPPER SNAKE HIGHLANDS ARE FAVORED...WITH AREAS CLOSER TO CHALLIS AND INTO LEMHI COUNTY SEEING A RAIN/SNOW SHADOW DUE TO THE OPPOSITE. IN GENERAL...THERE WILL BE A SHARP LINE BETWEEN PLENTIFUL MOISTURE AND RELATIVE DRY WEATHER FROM NORTHWEST TO SOUTHEAST. SNOW LEVELS WILL BE HIGH UNTIL LATE TOMORROW AFTERNOON. THEY WILL BE AROUND 7000-8000FT THIS AFTERNOON AND EVENING. OVERNIGHT...THEY WILL BE 7000-8000FT IN THE WEST AND 6000-7000FT IN THE EAST WHERE IT WILL DRY OUT OVERNIGHT. WEDNESDAY WILL SEE SNOW LEVELS BETWEEN 6500-7500FT EARLY AND DROPPING ABOUT 500FT OR SO IN THE AFTERNOON. FORECAST SNOW AMOUNTS ARE 5-15 INCHES AND LOCALLY CLOSER TO 20 INCHES ACROSS THE WESTERN PART OF THE CENTRAL MOUNTAINS. FOR THE REST OF THE CENTRAL MOUNTAINS AND UPPER SNAKE HIGHLANDS...2-7 INCHES IS POSSIBLE. IT WILL BE WINDY THROUGH THIS EVENT ESPECIALLY AT HIGHER ELEVATIONS. WINDS OF 10-20 MPH SUSTAINED ARE EXPECTED AT LOWER ELEVATIONS THROUGH WEDNESDAY MORNING...WITH 20-30 MPH SUSTAINED IN THE MOUNTAINS. THEY WILL PICK UP 5-10 MPH TOMORROW. FOR THE MOUNTAINS...THIS MEANS SOME BLOWING AND DRIFTING SNOW EVEN WITH A WET SNOW. FOR WEDNESDAY NIGHT AND THURSDAY...WE WILL QUICKLY DRY OUT ACROSS THE AREA AS THE MAIN SYSTEM SWINGS EAST. THERE WILL BE LINGERING PRECIPITATION ACROSS PORTIONS OF THE CENTRAL AND EASTERN MOUNTAINS WEDNESDAY NIGHT. IT WILL BE COLDER...BY 5-10 DEGREES ON THURSDAY VERSUS TODAY AND WEDNESDAY. KEYES .LONG TERM...THURSDAY NIGHT THROUGH TUESDAY. MODELS MAINTAIN GOOD AGREEMENT THROUGH MUCH OF THE EXTENDED RANGE WITH MINOR DIFFERENCES IN AMPLITUDE AND TIMING OF SYSTEMS. UPPER RIDGE BUILDS INTO THE REGION FOR MAIN DRY CONDITIONS THURSDAY NIGHT INTO FRIDAY. RIDGE FLATTENS ONCE AGAIN FRIDAY NIGHT INTO SATURDAY AS ENERGY SPINS OUT OF PACIFIC LOW THROUGH THE NORTHERN ROCKIES. TROUGH DEEPENS ACROSS EASTERN IDAHO SATURDAY NIGHT INTO SUNDAY FOR THE HIGHEST PRECIP CHANCES OF THE WEEKEND. REINFORCING SHORTWAVES KEEP NORTHWEST FLOW ACROSS THE REGION WITH CONTINUED WEAKLY UNSETTLED CONDITIONS MAINLY OVER HIGHER TERRAIN FOR MONDAY INTO TUESDAY. CONTINUED TO TREND TEMPS COOLER FOR SUNDAY AND BEYOND AFTER MAIN SYSTEM MOVES THROUGH. DMH && .AVIATION...CONDITIONS EXPECTED TO CONTINUE TO DETERIORATE ACROSS PORTIONS OF EASTERN IDAHO THIS MORNING AS PRECIPITATION MOVES INTO THE CENTRAL MOUNTAINS AND MAGIC VALLEY. LOOK FOR VFR AT KSUN AND KBYI TO DROP TO MVFR. PRECIP FOCUS SHIFTS NORTHEAST THROUGH THE DAY BUT GOOD SOUTHERLY FLOW SHOULD KEEP KPIH VFR AND MOSTLY DRY WITH KIDA ALSO REMAINING VFR BUT SEEING INCREASING POTENTIAL FOR RAIN INTO THIS AFTERNOON AND EVENING. A BRIEF BREAK IS POSSIBLE IN THE CENTRAL MOUNTAINS THIS EVENING BUT WILL RETURN FOR MUCH OF THE SAME AFTER 06Z THROUGH WEDNESDAY. DMH && .PIH WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 5 PM MST WEDNESDAY ABOVE 7500 FEET FOR THE IDZ018-031. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE POCATELLO ID 322 AM MST TUE NOV 20 2012 IDZ017>025-031-032-211030- EASTERN MAGIC VALLEY-SAWTOOTH MOUNTAINS-UPPER SNAKE HIGHLANDS- UPPER SNAKE RIVER PLAIN-LOWER SNAKE RIVER PLAIN- SOUTH CENTRAL HIGHLANDS-CARIBOU HIGHLANDS- CACHE VALLEY/IDAHO PORTION-WASATCH MOUNTAINS/IDAHO PORTION- BIG AND LITTLE WOOD RIVER REGION-LOST RIVER/PAHSIMEROI- 322 AM MST TUE NOV 20 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN IDAHO. .DAY ONE...TODAY AND TONIGHT RAIN AND MOUNTAIN SNOW WILL SPREAD EAST TODAY...BUT REMAIN GENERALLY NORTH AND WEST OF A LINE FROM PALISADES TO BURLEY. LITTLE TO NO PRECIPITATION IS FORECAST ELSEWHERE. RAIN AND SNOW CHANCES WILL RETREAT BACK INTO THE JUST THE CENTRAL MOUNTAINS TONIGHT FOR THE MOST PART. STRONG SOUTH TO SOUTHWEST WINDS OF 10-20 MPH SUSTAINED IN THE VALLEYS AND UP TO 30MPH IN THE MOUNTAINS IS EXPECTED. SNOW LEVELS TODAY WILL BE AROUND 7000-8000FT TODAY...AND REMAIN THERE ARE ACROSS WESTERN AREAS TONIGHT. THEY WILL DROP TO 6000-7000FT IN THE EAST AS PRECIPITATION ENDS. A WINTER STORM WARNING IS IN EFFECT INTO WEDNESDAY ACROSS THE WESTERN RANGES OF THE CENTRAL MOUNTAINS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY RAIN AND MOUNTAIN SNOW CONTINUES THROUGH TOMORROW. THE HIGHEST CHANCES OF SEEING RAIN AND SNOW WILL BE NORTH AND WEST OF A LINE FROM NEAR WAYAN TO CITY OF ROCKS. SNOW LEVELS WILL BE START AROUND 6500-7500FT IN THE MORNING AND DROP AROUND 500FT THROUGH THE DAY. STRONG WEST TO SOUTHWEST WINDS ARE LIKELY AS WELL. SNOW TOTALS IN THE WESTERN PART OF THE CENTRAL MOUNTAINS WILL BE 5-15 INCHES WITH LOCALLY HIGHER AMOUNTS. THE REST OF THE CENTRAL MOUNTAINS AND UPPER SNAKE HIGHLANDS WILL SEE 2-6 INCHES. WE WILL BE DRY FOR THANKSGIVING AND FRIDAY. FOR THOSE TRAVELLING SATURDAY AND SUNDAY...RAIN AND SNOW RETURNS AND COULD AFFECT TRAVEL IN THE MOUNTAINS. .SPOTTER INFORMATION STATEMENT... WE ASK TRAINED SPOTTERS AND CITIZENS TO REPORT SIGNIFICANT WEATHER CONDITIONS WHEN IT IS SAFE TO DO SO. THESE CONDITIONS MAY INCLUDE HAIL...TORNADOES...STRONG WIND...DUST STORMS...SNOWFALL... EXTREME COLD TEMPERATURES...FREEZING RAIN OR HEAVY RAIN...DENSE FOG...AND FLOODING OR ICE JAMS. INFORMATION ABOUT THESE HAZARDOUS CONDITIONS SHOULD BE CALLED INTO YOUR NATIONAL WEATHER SERVICE OFFICE IN POCATELLO USING THE 1-800 SEVERE WEATHER HOTLINE...OR 208-233-0834.
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE POCATELLO ID 339 AM MST TUE NOV 20 2012 IDZ019-032-202200- UPPER SNAKE HIGHLANDS-LOST RIVER/PAHSIMEROI- INCLUDING THE CITIES OF...DRIGGS...DUBOIS...ISLAND PARK... ST. ANTHONY...EDIE SCHOOL...ARCO...CHALLIS...MACKAY 339 AM MST TUE NOV 20 2012 ...SNOW AND STRONG WINDS WILL AFFECT NORTHERN MOUNTAIN RANGES THROUGH TOMORROW... A STEADY STREAM OF MOISTURE WILL PRODUCE RAIN AND MOUNTAIN SNOW ACROSS THE NORTH AND EAST RANGES WITHIN THE CENTRAL MOUNTAINS...AS WELL AS PORTIONS OF THE UPPER SNAKE HIGHLANDS. SNOW AMOUNTS OF 2 TO 7 INCHES ARE POSSIBLE ESPECIALLY AT OR ABOVE 7000 FEET. WINDS OF 15 TO 30 MPH WITH HIGHER GUSTS WILL CREATE BLOWING AND DRIFTING SNOW EVEN WITH THIS BEING A WET SNOWFALL. FOR THOSE TRAVELLING MOUNTAIN ROADS IN THESE AREAS NEED TO BE PREPARED FOR WINTER DRIVING CONDITIONS. STAY TUNED TO LOCAL MEDIA AND THE NATIONAL WEATHER SERVICE FOR THE LATEST INFORMATION ABOUT THIS PRE THANKSGIVING STORM. FOR THE LATEST ROAD CONDITIONS...YOU CAN CALL 5-1-1 OR CHECK OUT 5-1-1 DOT IDAHO DOT GOV ON THE WEB.
2 heavy snow. Local standard time, as filed.
Nine inches of snow fell at Galena with 10 inches at Galena Summit. Heavy snow also fell at Lost Wood Divide with 10 inches and Vienna Mine with 18 inches.
Ten inches of snow fell at Bear Canyon and Mill Creek Summit with 13 inches at Smiley Mountain.
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, November 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: 419484, 419485.