Alert archive / Wyoming / Flash Flood Warnings in 2020

Flash Flood Warning 2, NWS Cheyenne, WY

June 19, 2020Goshen County, Platte County, Wyoming

NWS Cheyenne, WY issued this flash flood warning at Jun 19, 2020, 2:34 PM MDT for Goshen County, Platte County, Wyoming. It was in force for 3 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 19, 2020, 2:34 PM MDT (20:34 UTC)
Expired
Jun 19, 2020, 5:30 PM MDT
In force
3 hr
Issued by
NWS Cheyenne, WY
Area
Storm-based polygon
Flood severity
None

Counties Goshen County, WY, Platte County, WY

The radar

The Cheyenne radar (KCYS), 102 km from the middle of the area, began a volume at 20:35 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.

What was reported inside it

TimeReportWhereRemark
Jun 19, 2:55 PM MDTFLASH FLOOD3 Ssw Fort Laramie, WYDEER CREEK ROAD (WEST OF ROAD 11).

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Rapid City, SD (KUNR), launched 12:00Z, 8.6 hours before the alert went out and 263 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 12:00Z on 2020-06-19Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 12:00Z on 2020-06-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -64 square meters per square second.1939587897117Sfc1 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
1186 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
-64 m²/s²
0-3 km storm-relative helicity
-4 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

044 
WGUS55 KCYS 192034
FFWCYS
WYC015-031-192330-
/O.NEW.KCYS.FF.W.0002.200619T2034Z-200619T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Cheyenne WY
234 PM MDT Fri Jun 19 2020

The National Weather Service in Cheyenne has issued a

* Flash Flood Warning for...
  West central Goshen County in southeastern Wyoming...
  Southeastern Platte County in southeastern Wyoming...

* Until 530 PM MDT.

* At 232 PM MDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding is ongoing or
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Emergency Manager report flash flooding of Cherry 
           Creek southwest of Lingle at 225 PM.

  IMPACT...Flooding of small creeks and streams, urban areas, 
           highways, streets and underpasses as well as other 
           drainage and low lying areas.

* Flash flooding will remain over mainly rural areas of west central
  Goshen and southeastern Platte Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

&&

LAT...LON 4197 10463 4201 10474 4221 10453 4212 10439

FLASH FLOOD...RADAR INDICATED

$$

Claycomb
1 follow-up statement
656 
WGUS75 KCYS 192323
FFSCYS

Flash Flood Statement
National Weather Service Cheyenne WY
523 PM MDT Fri Jun 19 2020

WYC015-031-192333-
/O.EXP.KCYS.FF.W.0002.000000T0000Z-200619T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Goshen WY-Platte WY-
523 PM MDT Fri Jun 19 2020

...THE FLASH FLOOD WARNING FOR WEST CENTRAL GOSHEN AND SOUTHEASTERN
PLATTE COUNTIES WILL EXPIRE AT 530 PM MDT...

The heavy rain has ended and flood waters have receded. Flooding is 
no longer expected to pose a threat. Please continue to heed any 
remaining road closures.

LAT...LON 4197 10463 4201 10474 4221 10453 4212 10439

$$

Trudel

Nearby

Flash Flood Warnings in Wyoming, 2020Every flash flood warning in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.