Alert archive / Nevada / Flash Flood Warnings in 2021
Flash Flood Warning 24, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood warning at Jul 18, 2021, 4:01 PM PDT for Clark County, Nevada. It was in force for 119 min. 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
- Jul 18, 2021, 4:01 PM PDT (23:01 UTC)
- Expired
- Jul 18, 2021, 6:00 PM PDT
- In force
- 119 min
- Issued by
- NWS Las Vegas, NV
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County Clark County, NV
The radar
The Las Vegas radar (KESX), 40 km from the middle of the area, began a volume at 23:04 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 18, 4:57 PM PDT | FLASH FLOOD | 1 Sse Sam Boyd Stadium, NV | 12 INCHES OF WATER FLOWING ACROSS ROADWAY AS EVIDENT BY WEB CAMERA. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Las Vegas, NV (KVEF), launched 12:00Z, 11.0 hours before the alert went out and 61 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
- 424 J/kg
- Mixed-layer CIN
- -164 J/kg
- Mixed-layer LCL
- 2704 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- -9 m²/s²
- 0-3 km storm-relative helicity
- 48 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
105
WGUS55 KVEF 182301
FFWVEF
NVC003-190100-
/O.NEW.KVEF.FF.W.0024.210718T2301Z-210719T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
401 PM PDT Sun Jul 18 2021
The National Weather Service in Las Vegas has issued a
* Flash Flood Warning for...
Southern Clark County in southern Nevada...
* Until 600 PM PDT.
* At 401 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across Old Henderson and portions southeast Las Vegas.
Flash flooding is ongoing or expected to begin shortly.
HAZARD...Life-threatening flash flooding. Thunderstorms
producing flash flooding.
SOURCE...Radar.
IMPACT...Life-threatening flash flooding of low-water
crossings, creeks, normally dry washes and roads.
* Some locations that will experience flash flooding include...
Henderson, Sam Boyd Stadium and East Las Vegas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3601 11496 3599 11496 3602 11506 3610 11505
3611 11502 3610 11495
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
CP2 follow-up statements
609
WGUS75 KVEF 182339
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
439 PM PDT Sun Jul 18 2021
NVC003-190100-
/O.CON.KVEF.FF.W.0024.000000T0000Z-210719T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
439 PM PDT Sun Jul 18 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 6 PM PDT THIS EVENING
FOR SOUTHERN CLARK COUNTY...
At 439 PM PDT, The thunderstorms that produced the heavy rainfall
across Old Henderson and southeast Las Vegas have weakened and moved
out of the area. However, flash flooding may be still occurring.
Over an inch of rainfall fell, resulting in over 12 feet of water
flowing in the Pioneer Drainage Basin. Flash flooding is ongoing or
expected to begin shortly.
HAZARD...Life-threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life-threatening flash flooding of low-water crossings,
creeks, normally dry washes and roads.
Some locations that will experience flash flooding include...
Henderson, Sam Boyd Stadium and East Las Vegas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3601 11496 3599 11496 3602 11506 3610 11505
3611 11502 3610 11495
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
CP531
WGUS75 KVEF 190054 RRA
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
554 PM PDT Sun Jul 18 2021
NVC003-190104-
/O.EXP.KVEF.FF.W.0024.000000T0000Z-210719T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
554 PM PDT Sun Jul 18 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 6 PM PDT THIS EVENING FOR
SOUTHERN CLARK COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 3601 11496 3599 11496 3602 11506 3610 11505
3611 11502 3610 11495
$$
CPThe office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 17, 5:33 PM PDT | Severe Thunderstorm Warning | VEF | Clark | 57 min |
| Jul 18, 1:05 PM PDT | Flash Flood Warning | VEF | Clark | 3 hr |
| Jul 18, 1:27 PM PDT | Areal Flood Advisory | VEF | Clark | 3 hr |
| Jul 18, 3:46 PM PDT | Flash Flood Warning | VEF | Clark | 2 hr |
| Jul 18, 4:33 PM PDT | Flash Flood Warning | VEF | Clark | 3 hr |
Nearby
Flash Flood Warnings in Nevada, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.