Alert archive / Wyoming / Flash Flood Watches in 2015

Flash Flood Watch 4, NWS Cheyenne, WY

June 10, 20156 counties in Wyoming; 6 counties in Nebraska

NWS Cheyenne, WY issued this flash flood watch at Jun 10, 2015, 3:39 AM MDT for 6 counties in Wyoming; 6 counties in Nebraska. It took effect at Jun 10, 2015, 12:00 PM MDT. It was in force for 30 hr.

The area

The counties it named.

The facts

Issued
Jun 10, 2015, 3:39 AM MDT (09:39 UTC)
In effect from
Jun 10, 2015, 12:00 PM MDT
Expired
Jun 11, 2015, 6:03 PM MDT
In force
30 hr
Issued by
NWS Cheyenne, WY
Flood severity
None

Counties Banner County, NE, Box Butte County, NE, Dawes County, NE, Kimball County, NE, Scotts Bluff County, NE, Sioux County, NE, Albany County, WY, Converse County, WY, Goshen County, WY, Laramie County, WY, Niobrara County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 116 km from the middle of the area, began a volume at 09:40 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

Rapid City, SD (KRAP), launched 00:00Z, 9.7 hours before the alert went out and 245 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, Rapid City, SD at 00:00Z on 2015-06-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2145 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, Rapid City, SD at 00:00Z on 2015-06-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -6 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
2145 J/kg
Mixed-layer CIN
-62 J/kg
Mixed-layer LCL
1943 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
-48 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Cheyenne, WY wrote its last area forecast discussion before this flash flood watch went out at Jun 9, 9:20 PM MDT, 6 hours 19 minutes earlier.

Area forecast discussion, Jun 9, 9:20 PM MDT, 6 hours 19 minutes before
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Hazardous weather outlook, Jun 9, 5:34 AM MDT, 22 hours 5 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHEYENNE WY
534 AM MDT TUE JUN 9 2015

WYZ101>119-101145-
CONVERSE COUNTY LOWER ELEVATIONS-NIOBRARA COUNTY-
NORTH LARAMIE RANGE-FERRIS/SEMINOE/SHIRLEY MOUNTAINS-
SHIRLEY BASIN-CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY-
EAST PLATTE COUNTY-GOSHEN COUNTY-CENTRAL CARBON COUNTY-
NORTH SNOWY RANGE FOOTHILLS-SOUTHWEST CARBON COUNTY-
SIERRA MADRE RANGE-UPPER NORTH PLATTE RIVER BASIN-SNOWY RANGE-
LARAMIE VALLEY-SOUTH LARAMIE RANGE-SOUTH LARAMIE RANGE FOOTHILLS-
CENTRAL LARAMIE COUNTY-EAST LARAMIE COUNTY-
534 AM MDT TUE JUN 9 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
WYOMING.

.DAY ONE...TODAY AND TONIGHT

A FEW AFTERNOON THUNDERSTORMS ARE POSSIBLE OVER THE MOUNTAINS.
ANY STORMS THAT FORM WILL MOVE TO THE SOUTHEAST. SEVERE WEATHER
IS NOT EXPECTED.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

TROPICAL MOISTURE FROM THE REMNANTS OF TROPICAL STORM BLANCA IN
THE EASTERN PACIFIC WILL MOVE NORTHEAST INTO SOUTHERN WYOMING
WEDNESDAY THROUGH THURSDAY. SHOWERS AND THUNDERSTORMS WILL BECOME
MORE NUMEROUS AT THAT TIME. SEVERE WEATHER IS NOT EXPECTED. GIVEN THE
ALREADY SATURATED SOILS...THERE IS THE POTENTIAL FOR ADDITIONAL
FLASH FLOODING IN SOME AREAS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT.

NEZ002-003-019>021-054-055-095-096-101145-
DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE-
NORTH SIOUX-SOUTH SIOUX-
534 AM MDT TUE JUN 9 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WESTERN
NEBRASKA.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

TROPICAL MOISTURE FROM THE REMNANTS OF TROPICAL STORM BLANCA
IN THE EASTERN PACIFIC WILL MOVE NORTHEAST INTO SOUTHEAST WYOMING
AND WESTERN NEBRASKA WEDNESDAY THROUGH THURSDAY. SHOWERS AND
THUNDERSTORMS WILL BECOME MORE NUMEROUS AT THAT TIME. A FEW STRONG
STORMS WITH SMALL HAIL AND GUSTY WINDS WILL BE POSSIBLE ON
WEDNESDAY. GIVEN THE ALREADY SATURATED SOILS...THERE IS THE
POTENTIAL FOR ADDITIONAL FLASH FLOODING IN SOME AREAS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY AND TONIGHT.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 9, 7:13 PM MDTSpecial Weather StatementCYSConverse62 min
Jun 10, 4:11 PM MDTSpecial Weather StatementCYSConverse49 min
Jun 10, 5:04 PM MDTSpecial Weather StatementCYSConverse41 min
Jun 10, 1:16 PM MDTSpecial Weather StatementCYSSioux44 min
Jun 10, 1:48 PM MDTFlash Flood WarningCYSSioux4 hr
Jun 10, 2:15 PM MDTSevere Thunderstorm WarningCYSSioux30 min
Jun 10, 2:47 PM MDTSevere Thunderstorm WarningCYSSioux22 min

Nearby

Flash Flood Watches in Wyoming, 2015Flash Flood Watches in Nebraska, 2015Every flash flood watch in 2015

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.