Alert archive / Idaho / Flash Flood Warnings in 1998

Flash Flood Warning 21, NWS Boise, ID

September 7, 1998Boise County, Gem County, Idaho

NWS Boise, ID issued this flash flood warning at Sep 7, 1998, 5:51 PM MDT for Boise County, Gem County, Idaho. It was in force for 59 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 7, 1998, 5:51 PM MDT (23:51 UTC)
Expired
Sep 7, 1998, 6:50 PM MDT
In force
59 min
Issued by
NWS Boise, ID
Area
Whole counties

Counties Boise County, ID, Gem County, ID

The nearest sounding before it

Boise Airport, ID (KBOI), launched 12:00Z, 11.9 hours before the alert went out and 52 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 12:00Z on 1998-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 1998-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 square meters per square second.1939Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2509 m above ground
0-6 km bulk shear
2 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
44 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KBOI 072355
FFWBOI
IDC015-045-080050-

BULLETIN -- IMMEDIATE BROADCAST REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE BOISE ID
551 PM MDT MON SEP 7 1998

THE NATIONAL WEATHER SERVICE IN BOISE HAS ISSUED A

* FLASH FLOOD WARNING FOR:
  SOUTHWESTERN BOISE COUNTY - WEST CENTRAL IDAHO
  SOUTHEASTERN GEM COUNTY - SOUTHWESTERN IDAHO

* UNTIL 650 PM MDT

* AT 542 PM...BOISE DOPPLER RADAR INDICATED A THUNDERSTORM 12
  MILES NORTH OF BOISE...MOVING NORTH AT 20 MPH.

* STORM SPOTTERS IN THE NORTHWEST PART OF BOISE REPORTED OVER
  NINE TENTHS OF AN INCH OF RAIN IN LESS THAN 15 MINUTES.

* FLASH FLOODING CAN BE EXPECTED IN THE FOLLOWING LOCATIONS:
  HORSESHOE BEND GRADE ALONG IDAHO HIGHWAY 55
  HORSESHOE BEND


DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE WATER COVERS THE
ROADWAY.  VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED
QUICKLY...MOVE TO HIGHER GROUND.

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 5:36 PM MDTFlash Flood WarningBOIAda64 min

Nearby

Flash Flood Warnings in Idaho, 1998Every flash flood warning in 1998

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.