Alert archive / Wyoming / Flash Flood Warnings in 2021
Flash Flood Warning 6, NWS Riverton, WY
NWS Riverton, WY issued this flash flood warning at Aug 2, 2021, 5:26 PM MDT for Park County, Wyoming. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Aug 2, 2021, 5:26 PM MDT (23:26 UTC)
- Expired
- Aug 2, 2021, 8:15 PM MDT
- In force
- 3 hr
- Issued by
- NWS Riverton, WY
- Area
- Storm-based polygon
- Flood severity
- None
County Park County, WY
The radar
The Billings radar (KBLX), 190 km from the middle of the area, began a volume at 23:26 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
Riverton, WY (KRIW), launched 12:00Z, 11.4 hours before the alert went out and 204 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2380 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 5 m²/s²
- 0-3 km storm-relative helicity
- 14 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
599
WGUS55 KRIW 022326
FFWRIW
WYC029-030215-
/O.NEW.KRIW.FF.W.0006.210802T2326Z-210803T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Riverton WY
526 PM MDT Mon Aug 2 2021
The National Weather Service in Riverton has issued a
* Flash Flood Warning for...
Central Park County in central Wyoming...
* Until 815 PM MDT.
* At 526 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...Radar.
IMPACT...Very heavy rainfall in a short amount of time could
cause debris flows of mainly mud and rock especially
over Sylvan Pass.
* Some locations that will experience flash flooding include...
East Entrance, Pahaska, Sylvan Pass and Sylvan Lake.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4452 11021 4449 11008 4455 10978 4445 10975
4440 10995 4443 11010 4446 11022
FLASH FLOOD...RADAR INDICATED
$$
Murrell2 follow-up statements
423
WGUS75 KRIW 030040
FFSRIW
Flash Flood Statement
National Weather Service Riverton WY
640 PM MDT Mon Aug 2 2021
WYC029-030215-
/O.CON.KRIW.FF.W.0006.000000T0000Z-210803T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Park WY-
640 PM MDT Mon Aug 2 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 815 PM MDT THIS
EVENING FOR CENTRAL PARK COUNTY...
At 640 PM MDT, Doppler radar indicated thunderstorms producing
moderate to heavy rain across portions of Sylvan Pass.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Very heavy rainfall in a short amount of time could
cause debris flows of mainly mud and rock especially
over Sylvan Pass.
Some locations that will experience flash flooding include...
East Entrance, Pahaska, Sylvan Pass and Sylvan Lake.
Motorists need to slow down, and be prepared for debris on the road
as they go over Sylvan Pass.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4452 11021 4449 11008 4455 10978 4445 10975
4440 10995 4443 11010 4446 11022
FLASH FLOOD...RADAR INDICATED
$$
Murrell750
WGUS75 KRIW 030213
FFSRIW
Flash Flood Statement
National Weather Service Riverton WY
813 PM MDT Mon Aug 2 2021
WYC029-030223-
/O.EXP.KRIW.FF.W.0006.000000T0000Z-210803T0215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Park WY-
813 PM MDT Mon Aug 2 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 815 PM MDT THIS EVENING FOR
CENTRAL PARK COUNTY...
The heavy rain has ended. The immediate threat for flooding is no
longer expected.
A Flash Flood Watch remains in effect until 1100 PM MDT for portions
of central Wyoming, northwest Wyoming, south central Wyoming,
southwest Wyoming and west central Wyoming.
LAT...LON 4452 11021 4449 11008 4455 10978 4445 10975
4440 10995 4443 11010 4446 11022
$$
MurrellThe office that day
Everything else NWS Riverton, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 2, 1:55 PM MDT | Areal Flood Advisory | RIW | Lincoln | 3 hr |
| Aug 2, 3:06 PM MDT | Areal Flood Advisory | RIW | Lincoln | 114 min |
| Aug 2, 3:20 PM MDT | Special Weather Statement | RIW | 25 min | |
| Aug 2, 3:36 PM MDT | Special Weather Statement | RIW | 24 min | |
| Aug 2, 3:48 PM MDT | Special Weather Statement | RIW | Teton | 27 min |
| Aug 2, 4:05 PM MDT | Areal Flood Advisory | RIW | Park, Teton | 2 hr |
| Aug 2, 4:13 PM MDT | Areal Flood Advisory | RIW | Teton | 2 hr |
| Aug 2, 4:28 PM MDT | Special Weather Statement | RIW | Teton | 32 min |
| Aug 2, 4:46 PM MDT | Flash Flood Warning | RIW | Lincoln | 2 hr |
| Aug 2, 4:57 PM MDT | Areal Flood Advisory | RIW | Teton | 48 min |
| Aug 2, 5:05 PM MDT | Special Weather Statement | RIW | Teton | 25 min |
Nearby
Flash Flood Warnings in Wyoming, 2021Every flash flood warning in 2021
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.