Alert archive / Washington / Flash Flood Warnings in 1991

Flash Flood Warning 2, NWS Seattle, WA

August 6, 1991Chelan County, Washington

NWS Seattle, WA issued this flash flood warning at Aug 6, 1991, 7:38 PM PDT for Chelan County, Washington. It was in force for 67 min.

The area

The counties it named.

The facts

Issued
Aug 6, 1991, 7:38 PM PDT (02:38 UTC)
Expired
Aug 6, 1991, 8:45 PM PDT
In force
67 min
Issued by
NWS Seattle, WA
Area
Whole counties

County Chelan County, WA

The nearest sounding before it

Spokane Intl Airport, WA (KGEG), launched 00:00Z, 2.6 hours before the alert went out and 235 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, Spokane Intl Airport, WA at 00:00Z on 1991-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 477 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, Spokane Intl Airport, WA at 00:00Z on 1991-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 54 square meters per square second.193958Sfc1 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
477 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
1891 m above ground
0-6 km bulk shear
29 kt
0-1 km storm-relative helicity
54 m²/s²
0-3 km storm-relative helicity
205 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.5

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

Everything else NWS Seattle, WA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 6, 7:54 PM PDTFlash Flood WarningSEWOkanogan66 min

Nearby

Flash Flood Warnings in Washington, 1991Every flash flood warning in 1991

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.