Alert archive / Idaho / Flash Flood Warnings in 2014

Flash Flood Warning 25, NWS Boise, ID

August 13, 2014Gem County, Payette County, Washington County, Idaho

NWS Boise, ID issued this flash flood warning at Aug 13, 2014, 8:08 PM MDT for Gem County, Payette County, Washington 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 13, 2014, 8:08 PM MDT (02:08 UTC)
Expired
Aug 13, 2014, 11:00 PM MDT
In force
3 hr
Issued by
NWS Boise, ID
Area
Storm-based polygon
Flood severity
None

Counties Gem County, ID, Payette County, ID, Washington County, ID

The radar

The Boise radar (KCBX), 83 km from the middle of the area, began a volume at 02:08 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 00:00Z, 2.1 hours before the alert went out and 76 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-pSkew-T log-p diagram, Boise Airport, ID at 00:00Z on 2014-08-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 278 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Boise Airport, ID at 00:00Z on 2014-08-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -49 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
278 J/kg
Mixed-layer CIN
-87 J/kg
Mixed-layer LCL
1521 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
-49 m²/s²
0-3 km storm-relative helicity
29 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-1.3

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 13, 3:04 PM MDT, 5 hours 4 minutes earlier.

Area forecast discussion, Aug 13, 3:04 PM MDT, 5 hours 4 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
304 PM MDT WED AUG 13 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A SEVERE THUNDERSTORM WATCH
IS IN EFFECT UNTIL 8 PM FOR PORTIONS OF SOUTHERN IDAHO. VERY MOIST
AND UNSTABLE AIR COMBINE WITH UPPER LEVEL WIND SHEAR WILL WILL
HELP DRIVE ISOLATED SEVERE STORMS IN THE WATCH AREA. PRIMARY
THREAT IN THE WATCH AREA IS FOR LARGE HAIL AND STRONG WIND GUSTS. SCATTERED
SHOWERS AND THUNDERSTORMS IN OTHER AREAS COULD ALSO PRODUCE GUSTY
WINDS AND SMALL HAIL THIS EVENING. MOST OF THE THUNDERSTORM
ACTIVITY WILL DIMINISH TOWARDS MIDNIGHT AS THE LOWER ATMOSPHERE
COOLS OFF. THUNDERSTORMS WILL LIKELY REDEVELOP ACROSS THE AREA
AGAIN TOMORROW AFTERNOON. SLIGHTLY DRIER CONDITIONS EXPECTED ON
FRIDAY.

LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY...A CHANGE TO A DRY
PATTERN IS ON THE WAY. TEMPERATURES ARE EXPECTED TO BE NEAR OR
SLIGHTLY ABOVE NORMAL. MODELS MOVE THE UPPER LEVEL TROUGH OUT OF
OUR AREA FRIDAY NIGHT WITH SHOWERS ENDING OVER OUR NORTHERN
MOUNTAINS BY SATURDAY MORNING. A BRIEF PERIOD OF ZONAL FLOW OVER
THE WEEKEND WILL BE FOLLOWED MONDAY AND TUESDAY BY AND UPPER LEVEL
RIDGE EXTENDING NORTH OVER SOUTHEAST OREGON AND SOUTHWEST IDAHO.

.AVIATION...EXPECT ISOLATED TO SCATTERED THUNDERSTORMS WITH LOCAL
MVFR/IFR CONDITIONS AND TERRAIN OBSCURATION IN HEAVY RAIN THROUGH
THIS EVENING. GUSTY OUTFLOW WINDS UP TO 45 KTS ARE POSSIBLE. AFTER
06Z THUNDERSTORMS WILL CONTINUE NORTH OF A KBNO-KONO-KTWF LINE...
BECOMING ISOLATED OVER THE HIGHER TERRAIN BY THURSDAY AFTERNOON.
AWAY FROM THUNDERSTORMS SURFACE WINDS WILL BE VARIABLE 5-15 KTS.
WINDS ALOFT WILL BE SOUTHERLY 15-25 KTS UP THROUGH 10K FEET MSL.

&&

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...RED FLAG WARNING UNTIL MIDNIGHT MDT TONIGHT IDZ400>403.
OR...RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING ORZ646.

&&

WEATHER.GOV/BOISE

SHORT TERM...JB
LONG TERM....JT/WH
AVIATION.....JT

In the hours before

Local storm report, Aug 13, 5:24 PM MDT, 2 hours 44 minutes before
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Local storm report, Aug 13, 5:49 PM MDT, 2 hours 19 minutes before
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Local storm report, Aug 13, 6:06 PM MDT, 2 hours 2 minutes before
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  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
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      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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Local storm report, Aug 13, 6:33 PM MDT, 1 hour 35 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BOISE ID
633 PM MDT WED AUG 13 2014

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0600 PM     HEAVY RAIN       15 N BOISE              43.82N 116.23W
08/13/2014  M0.87 INCH       BOISE              ID   TRAINED SPOTTER

            A TRAINED SPOTTER REPORTED 0.87 INCHES OF HEAVY RAINFALL
            WITHIN A 15 MINUTE TIME PERIOD ASSOCIATED WITH A
            TRANSIENT THUNDERSTORM. SOME MINOR WASH OUT NOTED.

&&

WHEWKO

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 14, 12:12 AM MDTSpecial Weather StatementBOIPayette48 min
Aug 14, 12:21 AM MDTSpecial Weather StatementBOIGem39 min
Aug 14, 12:26 AM MDTSpecial Weather StatementBOIPayette34 min
Aug 14, 12:38 AM MDTSpecial Weather StatementBOIAda37 min
Aug 14, 1:05 AM MDTSpecial Weather StatementBOICanyon25 min
Aug 14, 1:25 AM MDTSpecial Weather StatementBOI35 min
Aug 14, 1:30 AM MDTSpecial Weather StatementBOIGem30 min
Aug 14, 1:52 AM MDTSpecial Weather StatementBOIBoise38 min
Aug 14, 1:55 AM MDTSpecial Weather StatementBOI35 min
Aug 14, 2:30 AM MDTSpecial Weather StatementBOIBoise30 min
Aug 14, 4:11 AM MDTSpecial Weather StatementBOIGem34 min
Aug 14, 4:52 AM MDTSpecial Weather StatementBOIGem23 min
Aug 14, 7:11 AM MDTSpecial Weather StatementBOIGem34 min
Aug 14, 7:56 AM MDTSevere Thunderstorm WarningBOIBoise, Valley49 min
Aug 14, 2:26 AM MDTSpecial Weather StatementBOIBaker34 min
Aug 14, 2:59 AM MDTSpecial Weather StatementBOIBaker31 min
Aug 14, 3:27 AM MDTSpecial Weather StatementBOIBaker33 min
Aug 14, 3:13 PM MDTSpecial Weather StatementBOIBaker62 min
Aug 14, 4:04 PM MDTSpecial Weather StatementBOIBaker41 min

Nearby

Flash Flood Warnings in Idaho, 2014Every 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.