Alert archive / Idaho / Flash Flood Warnings in 2014

Flash Flood Warning 10, NWS Boise, ID

August 5, 2014Owyhee County, Idaho

NWS Boise, ID issued this flash flood warning at Aug 5, 2014, 3:59 PM MDT for Owyhee County, Idaho. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Aug 5, 2014, 3:59 PM MDT (21:59 UTC)
Expired: Aug 5, 2014, 6:45 PM MDT
In force: 3 hr
Issued by: NWS Boise, ID
Area: Storm-based polygon
Flood severity: None

County Owyhee County, ID

The radar

The Boise radar (KCBX), 101 km from the middle of the area, began a volume at 21:59 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Boise Airport, ID (KBOI), launched 12:00Z, 10.0 hours before the alert went out and 110 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 105 J/kg
Mixed-layer CIN: -133 J/kg
Mixed-layer LCL: 1570 m above ground
0-6 km bulk shear: 5 kt
0-1 km storm-relative helicity: 8 m²/s²
0-3 km storm-relative helicity: 103 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning went out, 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 this flash flood warning went out at Aug 5, 2:56 PM MDT, 1 hour 3 minutes earlier.

Area forecast discussion, Aug 5, 2:56 PM MDT, 1 hour 3 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
256 PM MDT TUE AUG 5 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY...SHOWERS AND THUNDERSTORMS
CONTINUE TO DEVELOP IN THE MOIST DEFORMATION AXIS WHICH STRETCHES
ACROSS SOUTHERN PORTIONS OF OUR CWA. MOST OF THE ACTIVITY HAS BEEN
ALONG THE ID/NV BORDER WHICH IS CLOSE TO THE CENTER OF THE AXIS. A
FEW SHOWERS/THUNDERSTORMS WERE ALSO FORMING IN THE BOISE
MOUNTAINS. THESE SAME AREAS WILL SEE ADDITIONAL SHOWERS AND STORMS
THROUGH THIS EVENING...AND SOME OF THE ACTIVITY MAY DEVELOP IN
THE VALLEY GENERALLY FROM MOUNTAIN HOME EAST. THE MOIST AXIS WILL
SHIFT A LITTLE FURTHER TO THE NORTH AND WEST ON WEDNESDAY. PWAT/S
LOWER SLIGHTLY BUT ARE STILL OVER AN INCH. THEREFORE...WILL BE
EXTENDING THE FLASH FLOOD WATCH THROUGH WEDNESDAY EVENING FOR THE
SAME ZONES. MOIST AXIS WILL START TO SHIFT EAST ON THURSDAY BUT
THE MOISTURE WILL LINGER FOR A CHANCE OF SHOWERS AND THUNDERSTORMS
IN SOUTHWEST IDAHO WITH DRIER STABLE AIR MOVING INTO SOUTHEAST
OREGON.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...SHORTWAVE TROUGH
FINALLY EXITS THE REGION FRIDAY MORNING LEAVING A MOIST AIRMASS
BEHIND. A UPPER LEVEL TROUGH MOVES INTO THE PACNW PROVIDING UPPER
LEVEL SUPPORT FOR AN ENHANCED PERIOD OF SHOWERS AND THUNDERSTORMS
OVER THE AREA FRIDAY AFTERNOON AND EVENING. THIS TROUGH SLOWLY MOVES
INLAND FOR COOLER TEMPERATURES AND A CHANCE OF SHOWERS AND
THUNDERSTORMS ON SATURDAY AFTERNOON. DIFFERENCES IN THE MODELS ARISE
ON SUNDAY IN THE UPPER LEVEL CHARACTERISTICS BUT STILL PROVIDE
SHOWERS AND THUNDERSTORMS AGAIN ON SUNDAY AFTERNOON THROUGH TUESDAY
AFTERNOON AS A TROUGH DIGS OFF THE CALIFORNIA COAST TAPPING INTO
MONSOONAL MOISTURE YET AGAIN.

&&

.AVIATION...VFR. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS SOUTH
OF A LINE FROM KREO-KBOI-KSNT WITH MVFR IN HEAVIER SHOWERS THROUGH
THIS EVENING. SURFACE WINDS NORTHERLY 5-15KT...EXCEPT IN VICINITY OF
THUNDERSTORMS WHERE GUSTS TO 40KT POSSIBLE. WINDS ALOFT AT 10K FT
MSL...NORTHEAST 5-15KT BECOMING VARIABLE 5-15KT BY 06Z WED.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...FLASH FLOOD WATCH THROUGH WEDNESDAY EVENING
     IDZ013-015-016-028>030.
OR...NONE.

&&

WEATHER.GOV/BOISE

SHORT TERM...BW
LONG TERM....KA/AB
AVIATION.....KA

The office that day

Everything else NWS Boise, ID issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 4, 6:17 PM MDT	Special Weather Statement	BOI	Gem	43 min
Aug 5, 7:15 AM MDT	Areal Flood Advisory	BOI	Jerome, Owyhee, Twin Falls	3 hr
Aug 5, 10:14 AM MDT	Areal Flood Advisory	BOI	Owyhee, Twin Falls	6 hr
Aug 5, 12:24 PM MDT	Areal Flood Advisory	BOI	Owyhee	4 hr
Aug 5, 4:10 PM MDT	Special Weather Statement	BOI	Owyhee	50 min
Aug 5, 4:14 PM MDT	Areal Flood Advisory	BOI	Owyhee, Twin Falls	4 hr
Aug 5, 4:42 PM MDT	Special Weather Statement	BOI	Elmore	33 min
Aug 5, 5:00 PM MDT	Flash Flood Warning	BOI	Elmore	3 hr
Aug 5, 5:08 PM MDT	Severe Thunderstorm Warning	BOI	Boise, Elmore	37 min
Aug 5, 5:42 PM MDT	Severe Thunderstorm Warning	BOI	Ada, Boise, Elmore	48 min

Nearby

Flash Flood Warnings in Idaho, 2014 Every flash flood warning in 2014

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.