Alert archive / Idaho / Flash Flood Warnings in 2013

Flash Flood Warning 8, NWS Boise, ID

September 4, 2013Gooding County, Jerome County, Twin Falls County, Idaho

NWS Boise, ID issued this flash flood warning at Sep 4, 2013, 6:05 PM MDT for Gooding County, Jerome County, Twin Falls County, Idaho. It was in force for 85 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Sep 4, 2013, 6:05 PM MDT (00:05 UTC)
Expired: Sep 4, 2013, 7:30 PM MDT
In force: 85 min
Issued by: NWS Boise, ID
Area: Storm-based polygon
Flood severity: None

Counties Gooding County, ID, Jerome County, ID, Twin Falls County, ID

The radar

The Pocatello radar (KSFX), 162 km from the middle of the area, began a volume at 00:08 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, 0.1 hours before the alert went out and 165 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: 126 J/kg
Mixed-layer CIN: -46 J/kg
Mixed-layer LCL: 3006 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 21 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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 Sep 4, 2:30 PM MDT, 3 hours 35 minutes earlier.

Area forecast discussion, Sep 4, 2:30 PM MDT, 3 hours 35 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
230 PM MDT WED SEP 4 2013

.SHORT TERM...TONIGHT THROUGH FRIDAY...VERY MOIST AIRMASS
CONTINUES OVER THE AREA THROUGH THURSDAY. UPPER LEVEL LOW OFF THE
COAST WILL BRING MORE JET ENERGY OVER THE AREA LATER TONIGHT AND
EARLY THURSDAY...INCREASING THE SHEAR ALOFT...WHICH SHOULD HELP
STORMS ORGANIZE AND LAST LONGER. WITH SUCH HIGH MOISTURE VALUES...
WE BELIEVE THAT FLASH FLOODING IS THE MAJOR THREAT...AND A FLASH
FLOOD WATCH IS OUT FOR ALL AREAS THROUGH THURSDAY. BUT THE
INCREASED SHEAR AND HIGH INSTABILITY MEANS THAT SEVERE WEATHER DUE
TO HAIL AND HIGH WINDS IS NOT OUT OF THE QUESTION EITHER. WILL BE
WATCHING CONVECTION CLOSELY. WITH SO MANY FACTORS IN PLACE...
EXPECT THE CONVECTION TO GO THROUGH THE NIGHT TONIGHT AND INTO
EARLY THURSDAY. BY LATE THURSDAY...MODELS AGREE THAT FLOW WILL
TURN TO THE SOUTHWEST BRINGING IN MUCH DRIER AIR AND QUICKLY DIMINISHING
THE STORM THREAT. COULD GET PRETTY BREEZY THURSDAY AFTERNOON...
ESPECIALLY IN THE HIGHER ELEVATIONS OF EASTER OREGON...AS THIS NEW
AIRMASS MOVES IN. TEMPERATURES WILL ALSO COOL AS THE AIRMASS
CHANGES...WITH HIGH TEMPERATURES ON FRIDAY BELOW NORMAL.

.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY. UPPER LEVEL LOW
CENTERED OVER EASTERN WASHINGTON WILL CONTINUE TO USHER IN COOLER
TEMPERATURES AND DRY AIR OVER THE REGION. MONDAY THE UPPER LEVEL LOW
BEGINS TO MOVE EASTWARD AND AN UPPER LEVEL RIDGE BEGINS TO BUILD
FROM THE SOUTHWEST. EXPECT TEMPERATURES TO GRADUALLY INCREASE FROM
AROUND NORMAL SATURDAY TO 5 TO 10 DEGREES ABOVE NORMAL BY WEDNESDAY
AS THE RIDGE MOVES OVER THE AREA.
&&

.AVIATION...VFR. EXPECT SHOWERS AND THUNDERSTORMS INCREASING IN
COVERAGE THIS AFTERNOON. MVFR CONDITIONS AND MOUNTAIN OBSCURATION IS
POSSIBLE NEAR SHOWERS AND THUNDERSTORMS. THUNDERSTORMS MAY PRODUCE
HEAVY RAIN AND HAIL WITH WIND GUSTS TO 40KT. WINDS ALOFT AT 10K FT
MSL WILL AVERAGE SOUTHWESTERLY AT 15KT.
&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON IDZ011>016-028>030-
     033.
OR...FLASH FLOOD WATCH THROUGH THURSDAY AFTERNOON ORZ061>064.
&&

WEATHER.GOV/BOISE

SHORT TERM...TB
LONG TERM....KA
AVIATION.....KA

Hazardous weather outlook, Sep 4, 5:52 AM MDT, 12 hours 13 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE BOISE ID
552 AM MDT WED SEP 4 2013

IDZ011>016-028>030-033-ORZ061>064-051200-
WEST CENTRAL MOUNTAINS-LOWER TREASURE VALLEY ID-BOISE MOUNTAINS-
UPPER TREASURE VALLEY-SOUTHWEST HIGHLANDS-WESTERN MAGIC VALLEY-
CAMAS PRAIRIE-OWYHEE MOUNTAINS-SOUTHERN TWIN FALLS COUNTY-
UPPER WEISER RIVER-HARNEY COUNTY-BAKER COUNTY-MALHEUR COUNTY-
LOWER TREASURE VALLEY OR-
552 AM MDT WED SEP 4 2013 /452 AM PDT WED SEP 4 2013/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL
IDAHO...SOUTHWEST IDAHO...WEST CENTRAL IDAHO...NORTHEAST OREGON
AND SOUTHEAST OREGON.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

In the hours before

Local storm report, Sep 4, 4:53 PM MDT, 1 hour 12 minutes before

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Local storm report, Sep 4, 5:09 PM MDT, 56 minutes before

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Local storm report, Sep 4, 5:30 PM MDT, 35 minutes before

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      <div class="status" id="status">Temporary Notice</div>
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Local storm report, Sep 4, 5:49 PM MDT, 16 minutes before

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<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.
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      <p id="message2">
        Please try again in a few minutes.
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      <p class="small" id="detail">
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The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 4, 6:17 PM MDT	Special Weather Statement	BOI	Ada	43 min
Sep 4, 6:18 PM MDT	Severe Thunderstorm Warning	BOI	Gooding, Jerome, Twin Falls	57 min
Sep 4, 7:03 PM MDT	Flash Flood Warning	BOI	Ada, Canyon, Owyhee	117 min
Sep 4, 9:38 PM MDT	Flash Flood Warning	BOI	Camas	112 min
Sep 5, 1:08 AM MDT	Special Weather Statement	BOI	Adams, Gem, Payette, Washington	52 min
Sep 5, 6:12 AM MDT	Special Weather Statement	BOI		63 min
Sep 5, 8:08 AM MDT	Special Weather Statement	BOI	Washington	52 min
Sep 5, 1:07 PM MDT	Special Weather Statement	BOI		53 min
Sep 5, 2:02 PM MDT	Severe Thunderstorm Warning	BOI	Canyon, Owyhee	43 min
Sep 5, 2:45 PM MDT	Severe Thunderstorm Warning	BOI	Ada, Canyon, Owyhee	60 min
Sep 5, 3:12 PM MDT	Flash Flood Warning	BOI	Camas	2 hr
Sep 5, 3:41 PM MDT	Flash Flood Warning	BOI	Owyhee	94 min
Sep 5, 3:43 PM MDT	Severe Thunderstorm Warning	BOI	Ada, Canyon, Owyhee	62 min
Sep 5, 3:59 PM MDT	Areal Flood Advisory	BOI	Ada, Canyon	3 hr
Sep 5, 4:11 PM MDT	Severe Thunderstorm Warning	BOI	Boise, Gem, Payette, Valley, Washington	64 min
Sep 5, 4:44 PM MDT	Severe Thunderstorm Warning	BOI	Jerome, Twin Falls	46 min
Sep 5, 4:52 PM MDT	Severe Thunderstorm Warning	BOI	Adams, Gem, Valley, Washington	38 min
Sep 5, 4:55 PM MDT	Flash Flood Warning	BOI	Adams, Boise, Gem, Valley, Washington	50 min
Sep 5, 5:05 PM MDT	Severe Thunderstorm Warning	BOI	Elmore, Gooding, Owyhee, Twin Falls	40 min
Sep 5, 5:10 PM MDT	Severe Thunderstorm Warning	BOI	Boise, Valley	35 min
Sep 5, 5:23 PM MDT	Severe Thunderstorm Warning	BOI	Jerome, Twin Falls	37 min
Sep 5, 5:27 PM MDT	Severe Thunderstorm Warning	BOI	Adams, Valley	48 min
Sep 5, 5:55 PM MDT	Severe Thunderstorm Warning	BOI	Jerome, Twin Falls	50 min
Sep 5, 5:59 PM MDT	Areal Flood Advisory	BOI	Jerome, Twin Falls	3 hr
Sep 4, 11:06 PM MDT	Areal Flood Warning	BOI	Harney, Malheur	6 hr

Nearby

Flash Flood Warnings in Idaho, 2013 Every flash flood warning in 2013

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.