Alert archive / Wyoming / Flash Flood Warnings in 1991

Flash Flood Warning 16, NWS Cheyenne, WY

June 21, 1991Albany County, Wyoming

NWS Cheyenne, WY issued this flash flood warning at Jun 21, 1991, 6:59 PM MDT for Albany County, Wyoming. It was in force for 4 hr.

The area

The counties it named.

The facts

Issued
Jun 21, 1991, 6:59 PM MDT (00:59 UTC)
Expired
Jun 21, 1991, 11:00 PM MDT
In force
4 hr
Issued by
NWS Cheyenne, WY
Area
Whole counties

County Albany County, WY

The nearest sounding before it

Lander/Hunt Fiel, WY (KLND), launched 00:00Z, 1.0 hours before the alert went out and 277 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, Lander/Hunt Fiel, WY at 00:00Z on 1991-06-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 759 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lander/Hunt Fiel, WY at 00:00Z on 1991-06-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 111 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
759 J/kg
Mixed-layer CIN
-141 J/kg
Mixed-layer LCL
2029 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
111 m²/s²
0-3 km storm-relative helicity
227 m²/s²
Significant tornado parameter
0.0
Supercell composite
5.6

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.

In the hours before

Special weather statement, Jun 21, 2:04 PM MDT, 4 hours 55 minutes before
WYZ016-212104-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
204 PM MDT FRI JUN 21 1991

...STRONG THUNDERSTORMS WERE DEVELOPING BETWEEN THE LARAMIE AND SNOWY
RANGES IN SOUTHEASTERN WYOMING...

AT 155 PM MDT...NATIONAL WEATHER SERVICE RADAR INDICATED STRONG
THUNDERSTORMS IN EAST CENTRAL CARBON COUNTY.  THE STRONGEST CELL
WAS LOCATED 45 MILES NORTHWEST OF LARAMIE...WHICH IS APPROXIMATELY
10 MILES NORTH OF ARLINGTON.  THE STORMS WERE MOVING NORTHWEST AT
20 MILES AN HOUR.

THESE THUNDERSTORMS WILL LIKELY PRODUCE HEAVY RAIN...PEA SIZED HAIL
...FREQUENT LIGHTNING...AND STRONG WINDS.  IF THIS STORM APPROACHES
...MOVE TO A SAFE SHELTER IMMEDIATELY.

PEOPLE IN EASTERN WYOMKING ARE ALSO REMINDED THAT A SEVERE THUNDERSTORM
WATCH REMAINS IN EFFECT UNTIL 800 PM MDT THIS EVENING.

VIRGILLITO
Special weather statement, Jun 21, 3:19 PM MDT, 3 hours 40 minutes before
WYZ016-212220-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
318 PM MDT FRI JUN 21 1991

...THUNDERSTORMS CONTINUED TO DEVELOP BETWEEN THE LARAMIE AND SNOWY
RANGES IN SOUTHEASTERN WYOMING...

AT 310 PM MDT...THUNDERSTORMS CONTINUED TO DEVELOP IN EAST CENTRAL
CARBON COUNTY AND WEST CENTRAL ALBANY COUNTY.  THE STRONGEST CELL WAS
LOCATED BETWEEN ARLINGTON AND ROCK RIVER...WHICH IS APPROXIMATELY 38
MILES NORTHWEST OF LARAMIE.  THESE STORMS WERE SHOWING LITTLE IF ANY
MOVEMENT.

THESE THUNDERSTORMS WILL LIKELY PRODUCE HEAVY RAIN...PEA SIZED HAIL
...FREQUENT LIGHTNING...AND STRONG WINDS.  FLOODING OF LOW LYING
AREAS AND ROADS IS ALSO LIKELY DUE TO THE SLOW MOVEMENT OF THESE
STORMS.  IF THESE STORMS APPROACH YOU...MOVE TO A SAFE SHELTER
IMMEDIATELY.
<
PEOPLE IN EASTERN WYOMING ARE ALSO REMINDED THAT A SEVERE THUNDERSTORM
WATCH REMAINS IN EFFECT UNTIL 800 PM MDT THIS EVENING.

VIRGILLITO
Special weather statement, Jun 21, 3:41 PM MDT, 3 hours 18 minutes before
WYZ017-212240-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
340 PM MDT FRI JUN 21 1991

...A STRONG THUNDERSTORM WAS MOVING INTO SOUTH CENTRAL LARAMIE COUNTY
FROM COLORADO...

AT 335 PM MDT...RADAR INDICATED A STRONG THUNDERSTORM ALONG THE
COLORADO/WYOMING BORDER ABOUT 10 MILES SOUTHWEST OF CHEYENNE.  THIS
STORM WAS MOVING NORTHEAST AT 15 MILES AN HOUR AND WILL REACH THE
SOUTHERN OUTSKIRTS OF CHEYENNE BY 350 PM MDT.

PEOPLE IN CHEYENNE AND THE SURROUNDING AREA CAN EXPECT HEAVY RAIN...
PEA SIZED HAIL...FREQUENT LIGHTNING...AND STRONG WINDS AS THIS STORM
MOVES THROUGH THE CITY.  BE PREPARED TO MOVE TO A SAFE SHELTER AS THIS
STORM MAY INTENSIFY.

VIRGILLITO
Special weather statement, Jun 21, 3:45 PM MDT, 3 hours 14 minutes before
WYZ017-212240-

SPECIAL WEATHER STATEMENT...CORRECTED
NATIONAL WEATHER SERVICE CHEYENNE WY
345 PM MDT FRI JUN 21 1991

...A STRONG THUNDERSTORM WAS MOVING INTO SOUTH CENTRAL LARAMIE COUNTY
FROM COLORADO...

AT 335 PM MDT...RADAR INDICATED A STRONG THUNDERSTORM ALONG THE
COLORADO/WYOMING BORDER ABOUT 10 MILES SOUTHWEST OF CHEYENNE.  THIS
STORM WAS MOVING NORTHEAST AT 15 MILES AN HOUR AND WILL REACH THE
SOUTHERN OUTSKIRTS OF CHEYENNE BY 350 PM MDT.

PEOPLE IN CHEYENNE AND THE SURROUNDING AREA CAN EXPECT HEAVY RAIN...
PEA SIZED HAIL...FREQUENT LIGHTNING...AND STRONG WINDS AS THIS STORM
MOVES THROUGH THE CITY.  BE PREPARED TO MOVE TO A SAFE SHELTER AS THIS
STORM MAY INTENSIFY.

PEOPLE IN EASTERN WYOMING ARE ALSO REMINDED THAT A SEVERE THUNDERSTORM
WATCH REMAINS IN EFFECT UNTIL 800 PM MDT THIS EVENING.

CORRECTED TO INCLUDE SEVERE THUNDERSTORM WATCH

VIRGILLITO
Special weather statement, Jun 21, 6:27 PM MDT, 32 minutes before
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Special weather statement, Jun 21, 6:45 PM MDT, 14 minutes before
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    <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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The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 22, 5:57 PM MDTTornado WarningCYSCheyenne, Morrill28 min
Jun 21, 7:16 PM MDTFlash Flood WarningCYSAlbany4 hr
Jun 21, 7:59 PM MDTFlash Flood WarningCYSAlbany, Platte4 hr
Jun 22, 2:12 PM MDTTornado WarningCYSLaramie48 min

Nearby

Flash Flood Warnings in Wyoming, 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.