An upper level trough pushed through North Central Idaho on 07/22/2008 and brought flash flooding, strong winds and hail to the area.
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 MSO wrote it up.
An upper level trough pushed through North Central Idaho on 07/22/2008 and brought flash flooding, strong winds and hail to the area.
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 Missoula, MT wrote its last area forecast discussion before the first event at Jul 22, 1:23 PM MST, 1 hour 7 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
223 PM MDT TUE JUL 22 2008
.DISCUSSION...AN UPPER LOW PRESSURE SYSTEM WILL IMPACT THE REGION
THROUGH THIS EVENING. THE MAIN IMPACTS SHOULD...FIRST...SIGNIFICANT
INSTABILITY SHOULD SUPPORT STRONG TO POSSIBLY SEVERE THUNDERSTORMS
FROM LEMHI COUNTY TO POSSIBLY BUTTE AREA THROUGH THIS AFTERNOON. WITH
A VERY MOIST AIR MASS IN PLACE...SOME STORMS MAY PRODUCE NEAR
FLASH FLOOD TYPE RAINFALL INTENSITIES. THE SECOND CONCERN IS THE
MORE GENERAL AREA OF MODERATE PRECIPITATION THAT IS EXPECTED WITH
THE MOISTURE AND MODEST ATMOSPHERE INSTABILITY FROM THE
CLEARWATERS...BITTERROOTS AND SAPPHIRES TO THE SEELEY LAKE AND
PINTLARS. HOWEVER...WITH THE BEST ENERGY AND MOISTURE FURTHER
SOUTH...AMOUNTS SHOULD NOT BE EXTREME...BUT POSSIBLY LOCALLY
HEAVY. THE THIRD CONCERN IS FROM THE CORE OF THE UPPER LOW
PRESSURE SYSTEM IS IT TRACKS NORTHEASTWARD ACROSS NORTHCENTRAL
IDAHO AND WESTERN MONTANA LATE THIS EVENING. WITHIN THE CORE OF
THIS SYSTEM THERE SHOULD BE SUFFICIENT INSTABILITY TO SUPPORT
ADDITIONAL STORMS...BUT ONLY EXPECTED TO BE ON THE MODERATE TO
POSSIBLY STRONG SIDE.
A DRYER SOUTHWEST FLOW IS EXPECTED TO DEVELOP LATE TONIGHT AND
EARLY WEDNESDAY. ANOTHER WEATHER DISTURBANCE IS EXPECTED TO SHIFT
NORTHEASTWARD ACROSS NORTHERN IDAHO AND WESTERN MONTANA LATE
WEDNESDAY AND SUPPORT A MARGINALLY UNSTABLE ATMOSPHERE. A DRYER
WESTERLY FLOW IS EXPECTED THURSDAY.
FRIDAY THROUGH SUNDAY...A HIGH PRESSURE RIDGE WILL BUILD ACROSS THE
NORTHERN ROCKIES. EXPECT DRY CONDITIONS AND TEMPERATURES INCREASING
INTO THE 90S.
MONDAY AND TUESDAY...MODELS CONTINUE TO AGREE ON THE SOLUTION OF A TROF
OFF OF THE WEST COAST. THIS TROF WILL INCREASE SOUTHWEST FLOW ALOFT
OVER THE REGION AND DRAW IN SOME MIDLEVEL MOISTURE WHICH MAY BE CONDUCIVE
FOR CONVECTION ACROSS SOUTHWEST MONTANA AND CENTRAL IDAHO.
&&
.AVIATION...A MOIST UPPER LOW PRESSURE SYSTEM IS EXPECTED TO
SUPPORT SHOWERS AND SCATTERED THUNDERSTORM ACROSS NORTHCENTRAL
IDAHO AND WESTCENTRAL MONTANA THROUGH THIS EVENING. AS THE AIR
MASS MOISTENS...INCREASING MOUNTAIN OBSCURATIONS WILL OCCUR.
ALSO...LOCAL LOW VISIBILITIES CAN BE EXPECTED WITHIN THE CORE OF
STRONGER STORMS. PARTIAL CLEAR LATE TONIGHT MAY ALLOW SOME LOW
CLOUD AND FOG FORMATION IN SOME VALLEYS.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
ID...FLASH FLOOD WATCH FOR THE SALMON RIVER CORRIDOR BETWEEN NORTH
FORK AND WHITEBIRD AND ALSO AREAS NEAR ELK BEND UNTIL 9 PM MDT
/8 PM PDT/ THIS EVENING
...SEVERE THUNDERSTORM WATCH 726 REMAINS IN EFFECT UNTIL 9 PM MDT
FOR LEMHI COUNTY
&&
SHORT TERM...BAUCK
LONG TERM....RPN
AVIATION...BAUCKHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MISSOULA MT 1036 AM MDT TUE JUL 22 2008 IDZ009-010-MTZ006-007-231100- WESTERN LEMHI COUNTY-EASTERN LEMHI COUNTY- BITTERROOT/SAPPHIRE MOUNTAINS-BUTTE/BLACKFOOT REGION- 1036 AM MDT TUE JUL 22 2008 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL IDAHO AND WEST CENTRAL MONTANA. .DAY ONE...TODAY AND TONIGHT A LOW PRESSURE SYSTEM WILL MOVE NORTHEAST ACROSS THE NORTH CENTRAL IDAHO AND WRN MONTANA TODAY AND TONIGHT. AS IT PASSES...STRONG TO SEVERE THUNDERSTORMS MAY DEVELOP OVER LEMHI COUNTY AND SPREAD NORTHEAST INTO SW MONTANA THIS AFTERNOON AND EVENING. THE MAIN CONCERNS WITH ANY STORM THAT DEVELOPS WILL BE FOR LARGE HAIL...FREQUENT LIGHTNING AND BRIEF HEAVY DOWNPOURS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY ANOTHER TROUGH OF LOW PRESSURE WILL APPROACH THE AREA WEDNESDAY AFTERNOON WITH A RENEWED THREAT OF SHOWERS AND THUNDERSTORMS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. IDZ005>008-MTZ002>005-043-231100- NORTHERN CLEARWATER MOUNTAINS-SOUTHERN CLEARWATER MOUNTAINS- OROFINO/GRANGEVILLE REGION-LOWER HELLS CANYON/SALMON RIVER REGION- WEST GLACIER REGION-FLATHEAD/MISSION VALLEYS- LOWER CLARK FORK REGION-MISSOULA/BITTERROOT VALLEYS- POTOMAC/SEELEY LAKE REGION- 1036 AM MDT TUE JUL 22 2008 /936 AM PDT TUE JUL 22 2008/ THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL IDAHO...NORTHWEST MONTANA AND WEST CENTRAL MONTANA. .DAY ONE...TODAY AND TONIGHT A LOW PRESSURE SYSTEM WILL MOVE INTO THE NORTHERN ROCKIES TODAY. AS THIS SYSTEM PASSES THROUGH THE AREA...WIDESPREAD SHOWERS WITH EMBEDDED THUNDERSTORMS ARE EXPECTED TO DEVELOP AND LAST INTO THE EARLY EVENING HOURS. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO LAST LONGER...A FEW HOURS AFTER MIDNIGHT IN NORTHWEST MONTANA. HEAVY RAIN SHOWERS...GUSTY WINDS AND SMALL HAIL WILL ALL BE POSSIBLE NEAR THUNDERSTORMS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY ANOTHER TROUGH OF LOW PRESSURE WILL APPROACH THE AREA WEDNESDAY AFTERNOON WITH A RENEWED THREAT OF SHOWERS AND THUNDERSTORMS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
329 PM MDT TUE JUL 22 2008
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0300 PM FLASH FLOOD 20 S SALMON 44.89N 113.89W
07/22/2008 LEMHI ID TRAINED SPOTTER
SEVERAL DEBRIS FLOWS REPORTED ALONG US HWY 93 NEAR ELK
BEND DUE TO .5 INCHES RAIN IN 30 MINUTES.
&&
LAKEThe Missoula radar (KMSX), 216 km away, was scanning. The volume nearest the first event began at 21:30 UTC.
3 flash flood, 2 hail, 2 thunderstorm wind. Local standard time, as filed.
Mud and debris flows reported along the Middle Fork of the Salmon River at mile markers 13, 15 and 58. At mile marker 15, a significant log jam occured which backed up the river and flooded Greyhound Camp.
A trained spotter reported hail that was a quarter to half dollar size near Elk Bend.
Local media received reports of minor debris flows along the North Fork of the Salmon River in and around the town of North Fork, ID and westward towards Shoup, ID from heavy rainfall that fell on the unstable slopes.
Salmon AWOS reported 66 mph wind gusts.
Trained spotter reported several debris flows which resulted in closing of a 10 mile stretch along Highway 93 between Salmon and Ellis from a half inch of rainfall in 30 minutes.
A trained spotter reported penny sized hail and 1.50 inches of rain in 40 minutes at Leadore.
Trained spotter in Leadore reported numerous downed trees along Highway 28.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2008Every state in 2008This day in weather historyWarnings in Idaho, July 2008
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: 127970, 127986, 128415, 127981, 128434, 127987, 127983.