Alert archive / Nevada / Flash Flood Warnings in 2021
Flash Flood Warning 25, NWS Las Vegas, NV
NWS Las Vegas, NV issued this flash flood warning at Jul 18, 2021, 4:33 PM PDT for Clark County, Nevada. It was in force for 3 hr. 4 reports 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, 4:33 PM PDT (23:33 UTC)
- Expired
- Jul 18, 2021, 7:45 PM PDT
- In force
- 3 hr
- 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), 89 km from the middle of the area, began a volume at 23:37 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, 5:39 PM PDT | FLASH FLOOD | 2 Ssw Moapa, NV | ROAD CLOSED DUE TO FLOODING WHERE THE MUDDY RIVER CROSSES. |
| Jul 18, 5:45 PM PDT | FLASH FLOOD | 4 E Moapa, NV | WATER FLOWING OVER I-15 NORTHBOUND WITH TRAFFIC BEING DIVERTED. |
| Jul 18, 5:50 PM PDT | FLASH FLOOD | Overton, NV | CORRECTS PREVIOUS FLASH FLOOD REPORT FROM OVERTON. FLOODING OVER ROAD BEGAN AS EARLY AS 550 PM BASED OFF OF VIDEO REPORTS. FLASH FLOODING OVER HWY 169 COMING OUT OF OVERTON WASH. ESTIMATED DEPTH ABOUT 2 FEET. |
| Jul 18, 6:50 PM PDT | FLASH FLOOD | Overton, NV | FLASH FLOODING OVER HWY 169 COMING OUT OF OVERTON WASH. ESTIMATED DEPTH ABOUT 2 FEET. |
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, 11.6 hours before the alert went out and 90 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.
872
WGUS55 KVEF 182333
FFWVEF
NVC003-190245-
/O.NEW.KVEF.FF.W.0025.210718T2333Z-210719T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
433 PM PDT Sun Jul 18 2021
The National Weather Service in Las Vegas has issued a
* Flash Flood Warning for...
Northeastern Clark County in southern Nevada...
* Until 745 PM PDT.
* At 433 PM PDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Flash flooding is ongoing or
expected to begin shortly in Moapa, Logandale, Valley of Fire
State Park, and Overton impacting State Route 168.
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...
Moapa Town, Overton, Moapa Valley, Logandale, Valley Of Fire and
Sr 168 Mile Marker 21.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3617 11445 3618 11456 3616 11473 3659 11489
3684 11489 3684 11452 3684 11428 3650 11439
3641 11439 3633 11444 3632 11444
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JV3 follow-up statements
365
WGUS75 KVEF 190011
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
511 PM PDT Sun Jul 18 2021
NVC003-190245-
/O.CON.KVEF.FF.W.0025.000000T0000Z-210719T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
511 PM PDT Sun Jul 18 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM PDT THIS
EVENING FOR NORTHEASTERN CLARK COUNTY...
At 511 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Flash flooding is ongoing or expected
to begin shortly in Moapa, Logandale, Valley of Fire State Park, and
Overton impacting State Route 168. Rainfall totals approach an inch
around Moapa.
HAZARD...Life-threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life-threatening flash flooding of low-water crossings,
creeks, normally dry washes and roads.
Some locations that will experience flash flooding include...
Moapa Town, Overton, Moapa Valley, Logandale, Valley Of Fire and
Sr 168 Mile Marker 21.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3617 11445 3618 11456 3616 11473 3659 11489
3684 11489 3684 11452 3684 11428 3650 11439
3641 11439 3633 11444 3632 11444
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JV065
WGUS75 KVEF 190212
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
712 PM PDT Sun Jul 18 2021
NVC003-190245-
/O.CON.KVEF.FF.W.0025.000000T0000Z-210719T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
712 PM PDT Sun Jul 18 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM PDT THIS
EVENING FOR NORTHEASTERN CLARK COUNTY...
At 712 PM PDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Flash flooding is ongoing or expected
to begin shortly in Moapa, Logandale, Valley of Fire State Park, and
Overton impacting State Route 168. Flooding has been reported in
Overton as well as Moapa along Hidden Valley Road.
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...
Moapa Town, Overton, Moapa Valley, Logandale, Valley Of Fire and
Sr 168 Mile Marker 21.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3617 11445 3618 11456 3616 11473 3659 11489
3684 11489 3684 11452 3684 11428 3650 11439
3641 11439 3633 11444 3632 11444
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
JV404
WGUS75 KVEF 190243
FFSVEF
Flash Flood Statement
National Weather Service Las Vegas NV
743 PM PDT Sun Jul 18 2021
NVC003-190253-
/O.EXP.KVEF.FF.W.0025.000000T0000Z-210719T0245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
743 PM PDT Sun Jul 18 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 745 PM PDT THIS EVENING FOR
NORTHEASTERN CLARK COUNTY...
Flood waters have begun to recede and heavy rainfall has ceased over
the warned area. Light-to-moderate rainfall continues, and areas may
continue to have residual flooding over the next hour. Heed all road
closures, if applicable.
LAT...LON 3617 11445 3618 11456 3616 11473 3659 11489
3684 11489 3684 11452 3684 11428 3650 11439
3641 11439 3633 11444 3632 11444
$$
JVThe 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, 4:01 PM PDT | Flash Flood Warning | VEF | Clark | 119 min |
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.