Alert archive / Nevada / Flash Flood Warnings in 2018

Flash Flood Warning 73, NWS Las Vegas, NV

July 19, 2018Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Jul 19, 2018, 12:40 PM PDT for Clark County, Nevada. 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: Jul 19, 2018, 12:40 PM PDT (19:40 UTC)
Expired: Jul 19, 2018, 3:30 PM PDT
In force: 3 hr
Issued by: NWS Las Vegas, NV
Area: Storm-based polygon
Flood severity: None

County Clark County, NV

The radar

The Las Vegas radar (KESX), 104 km from the middle of the area, began a volume at 19:41 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

Las Vegas, NV (KVEF), launched 12:00Z, 7.7 hours before the alert went out and 9 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1086 J/kg
Mixed-layer CIN: -186 J/kg
Mixed-layer LCL: 2450 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: -24 m²/s²
0-3 km storm-relative helicity: -7 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.0

Open this sounding in Storm Lab

The text

As transmitted.

890 
WGUS55 KVEF 191940
FFWVEF
NVC003-192230-
/O.NEW.KVEF.FF.W.0073.180719T1940Z-180719T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
1240 PM PDT THU JUL 19 2018

The National Weather Service in Las Vegas has issued a

* Flash Flood Warning for...
  Northwestern Clark County in southern Nevada...

* Until 330 PM PDT.

* At 1236 PM PDT, Doppler radar indicated thunderstorms producing
  heavy rain across the warned area. Flash flooding is expected to
  begin shortly.

* Some locations that will experience flooding include...
  Spring Mountains, Mt. Charleston, Mahogany Grove Campground, Kyle
  Canyon Campground, Fletcher View Campground, Indian Springs, 
  Willow Creek Campground and Hilltop Campground, Cold Creek Road, 
  Lee Canyon Road.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3641 11536 3625 11561 3645 11581 3660 11574
      3658 11560

$$

JS

2 follow-up statements

153 
WGUS75 KVEF 192101
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
201 PM PDT THU JUL 19 2018

NVC003-192230-
/O.CON.KVEF.FF.W.0073.000000T0000Z-180719T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
201 PM PDT THU JUL 19 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 PM PDT FOR
NORTHWESTERN CLARK COUNTY...

At 149 PM PDT, Doppler radar indicated thunderstorms continuing to 
produce heavy rain over the Spring Mountains. The most intense cell 
is near and south of Mt. Charleston with a second strong storm over 
Lee Canyon Road and Deer Creek Road. Local residents and visitors to 
the Spring Mountains should use caution this afternoon and be 
prepared for areas of flooding.

Some locations that will experience flooding include...
Spring Mountains, Mt. Charleston, Mahogany Grove Campground, Kyle
Canyon Campground, Fletcher View Campground, Indian Springs, Willow
Creek Campground, Hilltop Campground,  Lee Canyon Road.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3641 11536 3625 11561 3645 11581 3660 11574
      3658 11560

$$

JS

817 
WGUS75 KVEF 192225
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
325 PM PDT THU JUL 19 2018

NVC003-192231-
/O.EXP.KVEF.FF.W.0073.000000T0000Z-180719T2230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
325 PM PDT THU JUL 19 2018

...THE FLASH FLOOD WARNING FOR NORTHWESTERN CLARK COUNTY WILL EXPIRE
AT 330 PM PDT...

Thunderstorms over the Spring Mountains have dissipated and the 
heavy rain has ended. Elevated water levels in local washes will 
continue to recede and flooding is no longer expected to pose a 
threat. Please continue to heed any remaining road closures.

LAT...LON 3641 11536 3625 11561 3645 11581 3660 11574
      3658 11560

$$

JS

The office that day

Everything else NWS Las Vegas, NV issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 18, 5:54 PM PDT	Flash Flood Warning	VEF	Lincoln	3 hr
Jul 19, 3:46 AM PDT	Excessive Heat Watch	VEF	Clark, Lincoln, Nye	23 hr
Jul 19, 2:34 PM PDT	Areal Flood Advisory	VEF	Clark	3 hr

Nearby

Flash Flood Warnings in Nevada, 2018 Every flash flood warning in 2018

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.