Extreme heat across the Intermountain West created unstable conditions including dry thunderstorms and high downburst 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.
Extreme heat across the Intermountain West created unstable conditions including dry thunderstorms and high downburst 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 Jun 28, 2:02 PM MST, 3 hours 3 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
302 PM MDT SUN JUN 28 2015
.SHORT TERM...TONIGHT THROUGH TUESDAY...MID-LEVEL MOISTURE COUPLED
WITH AFTERNOON HEAT AND INSTABILITY WILL CONTINUE TO FEED SHOWER
AND THUNDERSTORM DEVELOPMENT OVER HIGHER TERRAIN. WEAK SHEAR...LIGHT
WINDS ALOFT AND SLIGHTLY MORE STABLE CONDITIONS WILL KEEP SHOWERS
AND STORMS OUT OF LOWER VALLEYS. COLLAPSING SHOWERS/STORMS ARE
LIKELY TO PRODUCE GUSTY OUTFLOW WINDS WITH SPEEDS UP TO 50 MPH
NEAR THE COLLAPSING CELLS. UPPER TROUGH SLOWLY TRACKS THROUGH PAC
NW OVERNIGHT INTO MONDAY. DYNAMICS ALONG THE SOUTHERN TAIL OF THE
TROUGH COUPLED WITH ELEVATED INSTABILITY WILL BE ENOUGH TO KEEP
SHOWERS AND STORMS GOING ACROSS EAST-CENTRAL OREGON AND THE WEST-
CENTRAL ID MTNS TONIGHT AND MONDAY. DRIER CONDITIONS WRAP AROUND
THE RIDGE INTO EASTERN OREGON AND CENTRAL IDAHO ON TUESDAY. THIS
WILL SHIFT THE FOCUS OF SHOWER AND THUNDERSTORM DEVELOPMENT TO
BOISE MTNS AND OR/ID HIGHLANDS ALONG THE NV BORDER. WITH RIDGE
AXIS AND SURFACE THERMAL TROUGH EAST OF THE AREA...MONDAY IS
SEVERAL DEGREES COOLER. ON TUESDAY INCREASED CLOUD COVER WILL TAKE
A COUPLE MORE DEGREES OFF OF TEMPERATURES OVER CENTRAL AND
SOUTHERN ZONES.
.LONG TERM...TUESDAY NIGHT THROUGH SUNDAY...UPPER LEVEL RIDGE
WILL SLOWLY SHIFT WESTWARD ACROSS THE GREAT BASIN. THE CENTER OF
THE RIDGE STAYS WELL SOUTH OF THE AREA /MAINLY IN UTAH AND NEVADA/
KEEPING THE HOTTEST TEMPERATURES SOUTH. NONETHELESS TEMPERATURES
WILL REMAIN 10-15 DEGREES ABOVE NORMAL THROUGH THE EXTENDED
PERIOD.
&&
.AVIATION....VFR WITH SCT-BKN HIGH LEVEL CLOUDS. ISOLATED SHOWERS
AND THUNDERSTORMS THIS AFTERNOON/EVENING IN SE OREGON AND THE HIGHER
TERRAIN OF SW IDAHO. SURFACE WINDS...VARIABLE 12KT OR LESS EXCEPT
GUSTS TO 45KT NEAR THUNDERSTORM OUTFLOWS. WINDS ALOFT...SOUTH-
SOUTHEAST 10-20KT AROUND 10K FEET MSL.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...HEAT ADVISORY UNTIL 9 PM MDT THIS EVENING IDZ012-014-033.
OR...HEAT ADVISORY UNTIL 9 PM MDT THIS EVENING ORZ064.
RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING ORZ636-646.
&&
WEATHER.GOV/BOISE
SHORT TERM...DG
LONG TERM....KA
AVIATION.....KAThe Boise radar (KCBX), 57 km away, was scanning. The volume nearest the first event began at 00:05 UTC.
1 thunderstorm wind. Local standard time, as filed.
The weather observer at Mountain Home AFB reported wind gusts of 60 MPH associated with an outflow boundary from a collapsing thunderstorm in the vicinity. Blowing dust restricting visibility at times was also reported.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Idaho in 2015Every state in 2015This day in weather historyWarnings in Idaho, June 2015
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: 582232.