Alert archive / South Dakota / Flash Flood Warnings in 1999

Flash Flood Warning 5, NWS Aberdeen, SD

July 22, 1999Sully County, South Dakota

NWS Aberdeen, SD issued this flash flood warning at Jul 22, 1999, 6:01 PM CDT for Sully County, South Dakota. It was in force for 2 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
Jul 22, 1999, 6:01 PM CDT (23:01 UTC)
Expired
Jul 22, 1999, 8:05 PM CDT
In force
2 hr
Issued by
NWS Aberdeen, SD
Area
Whole counties

County Sully County, SD

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 11.0 hours before the alert went out and 138 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, Aberdeen, SD at 12:00Z on 1999-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1958 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, Aberdeen, SD at 12:00Z on 1999-07-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 104 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
1958 J/kg
Mixed-layer CIN
-260 J/kg
Mixed-layer LCL
1086 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
104 m²/s²
0-3 km storm-relative helicity
140 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

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.

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 Aberdeen, SD wrote its last area forecast discussion before this flash flood warning went out at Jul 22, 3:19 PM CDT, 2 hours 42 minutes earlier.

Area forecast discussion, Jul 22, 3:19 PM CDT, 2 hours 42 minutes before
AREA FORECAST DISCUSSION FOR CENTRAL/NORTHCENTRAL AND NORTHEAST
SOUTH DAKOTA AND WEST CENTRAL MINNESOTA
NATIONAL WEATHER SERVICE ABERDEEN SD
315 PM CDT THU JULY 22 1999

TSRAS ALREADY BREAKING THROUGH THE CAP ALONG SFC TROUGH EXTENDING
ACROSS C AND NC SD LATE THIS AFTERNOON. SATELLITE DERIVED PRODUCTS
SHOWED A VERY UNSTABLE AIRMASS ACROSS MOST OF THE ABR CWA WITH LIS DOWN
TO -12 AND CAPES OF 4-6 THOUSAND. HIGH DWPTS IN THE MID TO UPPER 70S
AND TEMPS IN THE 90S TO OVER 100 WERE WEAKENING THE CAP. SATELLITE
PRODUCTS CINH SHOWED THE CAP WEAKENING THE FASTEST IN C SD WHERE TSRAS
ARE PRESENTLY DEVELOPING. ALSO...A GOOD THETA-E RIDGE IS IN PLACE OVER
NE SD AND WC MN. THEREFORE...AS TROUGH MOVES THROUGH TONIGHT...THERE
WILL BE A CHANCE OF TSRAS OVER ALL OF THE AREA. FRIDAY SHOULD AGAIN BE
A HOT DAY WITH LESS HUMIDITY AS DWPTS FALL INTO THE 60S. FOR FRIDAY
NIGHT AND SATURDAY...MDLS SHOW UPPER RIDGE HOLDING IN STRONG WITH UPPER
DISTURBANCES ROLING OVER IT. DUE TO THE TIMING AND STRENGTH OF THESE
WAVES...WILL LEAVE OUT POPS FOR THE CWA FOR FRIDAY NIGHT AND SATURDAY.
FOR SUNDAY THROUGH TUESDAY...THE WEATHER PATTERN CHANGES VERY
LITTLE...EXCEPT FOR ON MONDAY ACROSS NE SD AND WC MN WHERE THE AVN SHOWS
A S/W MOVING OVER THE AREA...SO WILL PUT IN A CHANCE OF TSRAS HERE. DID
NOT STRAY MUCH FROM GUIDANCE TEMPS.

.ABR...NONE.

MOHR

The office that day

Everything else NWS Aberdeen, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 22, 3:59 PM CDTSevere Thunderstorm WarningABRLyman46 min
Jul 22, 4:59 PM CDTSevere Thunderstorm WarningABRHughes, Stanley46 min
Jul 22, 5:17 PM CDTSevere Thunderstorm WarningABRSully48 min
Jul 22, 5:29 PM CDTTornado WarningABRPotter, Sully36 min
Jul 22, 6:18 PM CDTTornado WarningABRMcPherson32 min
Jul 22, 6:38 PM CDTTornado WarningABRMcPherson32 min
Jul 22, 6:50 PM CDTTornado WarningABREdmunds35 min

Nearby

Flash Flood Warnings in South Dakota, 1999Every flash flood warning in 1999

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.