Alert archive / Nevada / Flash Flood Warnings in 2017

Flash Flood Warning 40, NWS Las Vegas, NV

July 25, 2017Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Jul 25, 2017, 4:54 AM PDT for Clark County, Nevada. It was in force for 6 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: Jul 25, 2017, 4:54 AM PDT (11:54 UTC)
Expired: Jul 25, 2017, 10:45 AM PDT
In force: 6 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), 71 km from the middle of the area, began a volume at 11:57 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 25, 7:51 AM PDT	FLASH FLOOD	1 Ne Logandale, NV	INTERSECTION OF LYMAN STREET AND BERT CIRCLE REPORTED AS FLOODED. ROAD CLOSED.

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 00:00Z, 11.9 hours before the alert went out and 107 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: 183 J/kg
Mixed-layer CIN: -90 J/kg
Mixed-layer LCL: 2329 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 51 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

974 
WGUS55 KVEF 251154
FFWVEF
NVC003-251645-
/O.NEW.KVEF.FF.W.0040.170725T1154Z-170725T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
454 AM PDT TUE JUL 25 2017

The National Weather Service in Las Vegas has issued a

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

* Until 945 AM PDT

* At 452 AM PDT, Doppler radar indicated thunderstorms producing 
  heavy rain over much of eastern Clark County including northern 
  portions of the Lake Mead National Recreation Area. Flash flooding 
  is expected to begin shortly.

* Some locations that will experience flooding include...
  Overton, Moapa Valley, Echo Bay, Valley Of Fire, Callville Bay
  Campground, Overton Beach, Echo Bay Campground, Callville Bay, 
  Logandale, Lake Mead National Recreation Area and Bunkerville, 
  North Shore Road.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3611 11412 3609 11411 3603 11415 3601 11424
      3605 11427 3606 11432 3608 11431 3614 11437
      3615 11441 3612 11445 3614 11446 3613 11451
      3614 11450 3615 11458 3611 11474 3618 11477
      3631 11467 3670 11452 3671 11405 3620 11405

$$

ASG

3 follow-up statements

039 
WGUS75 KVEF 251325
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
625 AM PDT TUE JUL 25 2017

NVC003-251645-
/O.CON.KVEF.FF.W.0040.000000T0000Z-170725T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
625 AM PDT TUE JUL 25 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 945 AM PDT FOR
NORTHEASTERN CLARK COUNTY...

At 623 AM PDT, Doppler radar indicated thunderstorms producing heavy 
rain across eastern Clark County. Flash flooding is likely occurring.

Some locations that will experience flooding include...
Overton, Moapa Valley, Echo Bay, Valley Of Fire, Callville Bay
Campground, Overton Beach, Echo Bay Campground, Callville Bay,
Logandale, Lake Mead National Recreation Area and Bunkerville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3611 11412 3609 11411 3603 11415 3601 11424
      3605 11427 3606 11432 3608 11431 3614 11437
      3615 11441 3612 11445 3614 11446 3613 11451
      3614 11450 3615 11458 3611 11474 3618 11477
      3631 11467 3670 11452 3671 11405 3620 11405

$$

112 
WGUS75 KVEF 251510
FFSVEF

Flash Flood Statement
National Weather Service Las Vegas NV
810 AM PDT TUE JUL 25 2017

NVC003-251645-
/O.CON.KVEF.FF.W.0040.000000T0000Z-170725T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Clark NV-
810 AM PDT TUE JUL 25 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 945 AM PDT FOR
NORTHEASTERN CLARK COUNTY...

At 808 AM PDT, Clark County Fire reported flooding occuring in 
Logandale. While rain may begin to lighten in the next hour, runoff 
from higher terrain will still impact low areas as well as creeks 
and rivers.

Some locations that will experience flooding include...
Overton, Moapa Valley, Echo Bay, Valley Of Fire, Callville Bay
Campground, Overton Beach, Echo Bay Campground, Callville Bay,
Logandale, Lake Mead National Recreation Area and Bunkerville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3611 11412 3609 11411 3603 11415 3601 11424
      3605 11427 3606 11432 3608 11431 3614 11437
      3615 11441 3612 11445 3614 11446 3613 11451
      3614 11450 3615 11458 3611 11474 3618 11477
      3631 11467 3670 11452 3671 11405 3620 11405

$$

STEELE

109 
WGUS55 KVEF 251637
FFWVEF
NVC003-251745-
/O.EXT.KVEF.FF.W.0040.000000T0000Z-170725T1745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Las Vegas NV
937 AM PDT TUE JUL 25 2017

The National Weather Service in Las Vegas has extended the

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

* Until 1045 AM PDT

* At 936 AM PDT, Rain was ending, but flooding is ongoing, 
  especially in low lying areas and the Muddy River. Flooding will 
  likely continue for the next hour or so as runoff reaches lower 
  lying areas.

* Some locations that will experience flooding include...
  Overton, Moapa Valley, Echo Bay, Valley Of Fire, Callville Bay
  Campground, Overton Beach, Echo Bay Campground, Callville Bay,
  Logandale, Lake Mead National Recreation Area and Bunkerville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3611 11412 3609 11411 3603 11415 3601 11424
      3605 11427 3606 11432 3608 11431 3614 11437
      3615 11441 3612 11445 3614 11446 3613 11451
      3614 11450 3615 11458 3611 11474 3618 11477
      3631 11467 3670 11452 3671 11405 3620 11405

$$

STEELE

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 24, 5:39 PM PDT	Areal Flood Advisory	VEF	Lincoln	3 hr
Jul 24, 7:13 PM PDT	Flash Flood Warning	VEF	Lincoln	3 hr
Jul 24, 9:34 PM PDT	Flash Flood Warning	VEF	Clark	3 hr
Jul 24, 11:59 PM PDT	Flash Flood Watch	VEF	Clark, Nye	20 hr
Jul 25, 12:43 AM PDT	Areal Flood Advisory	VEF	Lincoln	4 hr
Jul 25, 2:15 AM PDT	Flash Flood Warning	VEF	Clark	3 hr
Jul 25, 5:42 AM PDT	Flash Flood Warning	VEF	Lincoln	10 hr
Jul 25, 6:55 AM PDT	Flash Flood Warning	VEF	Clark	5 hr
Jul 25, 8:06 AM PDT	Flash Flood Warning	VEF	Clark	8 hr
Jul 25, 10:28 AM PDT	Areal Flood Advisory	VEF	Clark	3 hr
Jul 25, 10:47 AM PDT	Areal Flood Advisory	VEF	Clark	6 hr
Jul 25, 11:06 AM PDT	Flash Flood Warning	VEF	Clark	6 hr
Jul 25, 1:57 PM PDT	Areal Flood Advisory	VEF	Esmeralda	4 hr
Jul 25, 2:57 PM PDT	Flash Flood Warning	VEF	Lincoln, Nye	3 hr
Jul 25, 4:23 PM PDT	Flash Flood Warning	VEF	Lincoln, Nye	3 hr

Nearby

Flash Flood Warnings in Nevada, 2017 Every flash flood warning in 2017

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.