Alert archive / Nevada / Severe Thunderstorm Warnings in 2017
Severe Thunderstorm Warning 15, NWS Las Vegas, NV
NWS Las Vegas, NV issued this severe thunderstorm warning at Jul 18, 2017, 4:25 PM PDT for Clark County, Nevada; Mohave County, Arizona. It was in force for 50 min. 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 18, 2017, 4:25 PM PDT (23:25 UTC)
- Expired
- Jul 18, 2017, 5:15 PM PDT
- In force
- 50 min
- Issued by
- NWS Las Vegas, NV
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 70.0 mph
Counties Mohave County, AZ, Clark County, NV
The radar
The Las Vegas radar (KESX), 29 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.
Did it verify
Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.
Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.
The nearest sounding before it
Las Vegas, NV (KVEF), launched 12:00Z, 11.4 hours before the alert went out and 86 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
- 750 J/kg
- Mixed-layer CIN
- -232 J/kg
- Mixed-layer LCL
- 2438 m above ground
- 0-6 km bulk shear
- 7 kt
- 0-1 km storm-relative helicity
- -5 m²/s²
- 0-3 km storm-relative helicity
- 36 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
196
WUUS55 KVEF 182325
SVRVEF
AZC015-NVC003-190015-
/O.NEW.KVEF.SV.W.0015.170718T2325Z-170719T0015Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Las Vegas NV
425 PM PDT TUE JUL 18 2017
The National Weather Service in Las Vegas has issued a
* Severe Thunderstorm Warning for...
Northwestern Mohave County in northwestern Arizona...
Central Clark County in southern Nevada...
* Until 515 PM PDT/515 PM MST/
* At 423 PM PDT/423 PM MST/, a severe thunderstorm was located near
Boulder City, moving north at 20 mph.
HAZARD...70 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Expect considerable tree damage. Damage is likely to
mobile homes, roofs, and outbuildings.
* Locations impacted include...
Henderson, Boulder City, Las Vegas Bay, Lake Las Vegas, The Motor
Speedway, East Las Vegas, Boulder Beach, Railroad Pass, Boulder
Beach Campground, Las Vegas Bay Campground, Callville Bay, Hoover
Dam, Callville Bay Campground, Willow Beach, Sunrise Mtn and
Frenchman Mtn.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
If on or near Lake Mead, get away from the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 15 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.
&&
LAT...LON 3571 11467 3574 11500 3627 11503 3624 11442
TIME...MOT...LOC 2323Z 187DEG 21KT 3593 11483
HAIL...<.75IN
WIND...70MPH
$$
Czyzyk4 follow-up statements
167
WWUS55 KVEF 182339
SVSVEF
Severe Weather Statement
National Weather Service Las Vegas NV
439 PM PDT TUE JUL 18 2017
AZC015-NVC003-190015-
/O.CON.KVEF.SV.W.0015.000000T0000Z-170719T0015Z/
Mohave AZ-Clark NV-
439 PM PDT TUE JUL 18 2017
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM
PDT/515 PM MST/ FOR NORTHWESTERN MOHAVE AND CENTRAL CLARK COUNTIES...
At 437 PM PDT/437 PM MST/, a severe thunderstorm was located over
Boulder Beach Campground, or near Boulder City, moving north at 20
mph.
HAZARD...70 mph wind gusts and quarter size hail.
SOURCE...Radar indicated.
IMPACT...Hail damage to vehicles is expected. Expect considerable
tree damage. Wind damage is also likely to mobile homes,
roofs, and outbuildings.
Locations impacted include...
Henderson, Boulder City, Las Vegas Bay, Lake Las Vegas, The Motor
Speedway, East Las Vegas, Boulder Beach, Railroad Pass, Boulder Beach
Campground, Las Vegas Bay Campground, Callville Bay, Hoover Dam,
Callville Bay Campground, Willow Beach, Sunrise Mtn and Frenchman
Mtn.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
If on or near Lake Mead in the Boulder Basin, get away from the
water and move indoors or inside a vehicle. remember, lightning can
strike out to 15 miles from the parent thunderstorm. If you can hear
thunder, you are close enough to be struck by lightning. Move to
safe shelter now! Do not be caught on the water in a thunderstorm.
&&
LAT...LON 3571 11467 3574 11500 3627 11503 3624 11442
TIME...MOT...LOC 2337Z 187DEG 21KT 3601 11482
HAIL...1.00IN
WIND...70MPH
$$
Czyzyk627 WWUS55 KVEF 182351 SVSVEF Severe Weather Statement National Weather Service Las Vegas NV 451 PM PDT TUE JUL 18 2017 AZC015-NVC003-190015- /O.CON.KVEF.SV.W.0015.000000T0000Z-170719T0015Z/ Mohave AZ-Clark NV- 451 PM PDT TUE JUL 18 2017 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM PDT/515 PM MST/ FOR NORTHWESTERN MOHAVE AND CENTRAL CLARK COUNTIES... At 450 PM PDT/450 PM MST/, a severe thunderstorm was located near Boulder Beach, or near Las Vegas Bay, moving northeast at 20 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Henderson, Boulder City, Las Vegas Bay, Lake Las Vegas, East Las Vegas, Boulder Beach, Railroad Pass, Boulder Beach Campground, Las Vegas Bay Campground, Callville Bay, Hoover Dam, Callville Bay Campground, Willow Beach, Sunrise Mtn and Frenchman Mtn. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. Wind damage with this storm will occur before any rain or lightning. Do not wait for the sound of thunder before taking cover. SEEK SHELTER IMMEDIATELY inside a sturdy structure and stay away from windows. If on or near Lake Mead in the vicinity of Boulder Basin, get away from the water and move indoors or inside a vehicle. remember, lightning can strike out to 15 miles from the parent thunderstorm. If you can hear thunder, you are close enough to be struck by lightning. Move to safe shelter now! Do not be caught on the water in a thunderstorm. && LAT...LON 3571 11467 3574 11500 3627 11503 3624 11442 TIME...MOT...LOC 2350Z 204DEG 19KT 3608 11476 HAIL...<.75IN WIND...60MPH $$ Czyzyk
051 WWUS55 KVEF 190003 SVSVEF Severe Weather Statement National Weather Service Las Vegas NV 503 PM PDT TUE JUL 18 2017 AZC015-NVC003-190015- /O.CON.KVEF.SV.W.0015.000000T0000Z-170719T0015Z/ Mohave AZ-Clark NV- 503 PM PDT TUE JUL 18 2017 ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM PDT/515 PM MST/ FOR NORTHWESTERN MOHAVE AND CENTRAL CLARK COUNTIES... At 502 PM PDT/502 PM MST/, a severe thunderstorm was located 9 miles northeast of Callville Bay Campground, or 16 miles east of Las Vegas Bay, in the narrows on Lake Mead, moving northeast at 15 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. Locations impacted include... Henderson, Boulder City, Las Vegas Bay, Lake Las Vegas, The Motor Speedway, East Las Vegas, Boulder Beach, Railroad Pass, Boulder Beach Campground, Las Vegas Bay Campground, Callville Bay, Hoover Dam, Callville Bay Campground, Willow Beach, Sunrise Mtn and Frenchman Mtn. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. If on or near Lake Mead in the narrows, get away from the water and move indoors or inside a vehicle. remember, lightning can strike out to 15 miles from the parent thunderstorm. If you can hear thunder, you are close enough to be struck by lightning. Move to safe shelter now! Do not be caught on the water in a thunderstorm. && LAT...LON 3571 11467 3574 11500 3627 11503 3624 11442 TIME...MOT...LOC 0002Z 202DEG 21KT 3620 11458 HAIL...<.75IN WIND...60MPH $$ Czyzyk
214
WWUS55 KVEF 190016
SVSVEF
Severe Weather Statement
National Weather Service Las Vegas NV
516 PM PDT TUE JUL 18 2017
AZC015-NVC003-190025-
/O.EXP.KVEF.SV.W.0015.000000T0000Z-170719T0015Z/
Mohave AZ-Clark NV-
516 PM PDT TUE JUL 18 2017
...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN MOHAVE AND
CENTRAL CLARK COUNTIES HAS EXPIRED...
The storm which prompted the warning has moved east and out of the
area. Therefore the warning has been allowed to expire for Boulder
City and eastern Las Vegas, but a new Severe Thunderstorm has been
issued for Lake Mead including the Narrows and the Overton Arm.
LAT...LON 3571 11467 3574 11500 3627 11503 3624 11442
TIME...MOT...LOC 0015Z 187DEG 21KT 3626 11457
$$
CzyzykWhat forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Las Vegas, NV wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 18, 3:28 PM PDT, 57 minutes earlier.
Area forecast discussion, Jul 18, 3:28 PM PDT, 57 minutes before
Area Forecast Discussion National Weather Service Las Vegas NV 328 PM PDT Tue Jul 18 2017 .SYNOPSIS...A moist and unstable airmass will result in scattered to numerous thunderstorms and locally heavy rainfall across southern Nevada...Northwest Arizona...and far eastern California through this evening. Drier conditions are expected across most of Inyo county where temperatures will remain hot and skies mostly sunny. Some drying is expected beginning Thursday but there will still be thunderstorm chances through the weekend mainly over Mohave County and eastern portions of Lincoln, Clark and San Bernardino Counties. && .DISCUSSION...Things fired back up over Mohave County after a bit of a lull in the action and some of that activity looks like it could be producing heavy rain. The rest of the area has been slow to get going after the air mass got worked over early this morning. Models still indicate decent cape and precipitable water is 1.5 to 2.1 inches and if clouds can thin some more and temperatures manage to pop up, there could still be a threat of thunderstorms with heavy rain over Clark and eastern San Bernardino County. So, I left the Flash Flood Watch going through 8 pm. There is still a possibility of early cancellation however. By Thursday, it looks like we lose the influence of the circulations which were moving through the area today. However, the air mass remains pretty moist and somewhat unstable over southeast Nevada, northwest Arizona and eastern San Bernardino Counties through the remainder of the week, leading to a chance of mainly afternoon and early evening thunderstorms. Inyo, Nye, Esmeralda and western San Bernardino County will remain dry and stable. Not much confidence in the pattern evolution late this weekend through early next week. For now I kept thunderstorm chances mainly over Mohave County Sunday and Monday with a little westward expansion Tuesday but confidence is low. Temperatures are forecast to remain fairly close to normal from Thursday through Tuesday. && .AVIATION...For McCarran...There is still a slim chance of thunderstorms developing again for the late afternoon and early evening in or near the Las Vegas Valley. Confidence is pretty low however. Winds mainly look to be south to southeast under 10 knots through early this evening. Winds late this evening through tonight should be south/southwest under 10 knots. We may see a brief period of light east to southeast Thursday morning but overall it looks like winds will be south around 10 knots much of the day. For the rest of southern Nevada, northwest Arizona and southeast California...Outside of erratic thunderstorm wind gusts, winds will mainly be southerly 5-15 kts with gusts 20-25 kts through Thursday. However, there could be several hours of light and variable winds tonight. && .HYDROLOGY...Creeks, streams and rivers in northern Inyo County continue to run high and fast from snow melt. Some road closures continue in the area. Bishop Creek Bypass and Big Pine Creek Bypass continue to be utilized to minimize flows through Bishop and Big Pine. Remember, never drive through flooded roadways or around barricades. Also, pastureland or farmland adjacent to creeks, streams or rivers could experience areas of standing water. && .SPOTTER INFORMATION STATEMENT...Spotters are encouraged to report any significant weather or impacts according to standard operating procedures. && Discussion...Harrison For more forecast information...see us on our webpage: http://weather.gov/lasvegas or follow us on Facebook and Twitter
In the hours before
Local storm report, Jul 18, 12:00 PM PDT, 4 hours 25 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1200 PM PDT TUE JUL 18 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0252 PM TSTM WND DMG 1 N ENTERPRISE 36.03N 115.24W
07/17/2017 CLARK NV PUBLIC
LARGE TREE DOWNED NEAR S RAINBOW AND W
WIGWAM AVE. PICTURE SENT IN VIA SOCIAL
MEDIA.
&&
CKLocal storm report, Jul 18, 2:42 PM PDT, 1 hour 43 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LAS VEGAS NV
242 PM PDT TUE JUL 18 2017
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0230 PM HAIL 17 S PEACH SPRINGS 35.29N 113.37W
07/18/2017 E1.00 INCH MOHAVE AZ CO-OP OBSERVER
&&The office that day
Everything else NWS Las Vegas, NV issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 17, 5:01 PM PDT | Areal Flood Advisory | VEF | Lincoln | 3 hr |
| Jul 18, 3:29 AM PDT | Flash Flood Watch | VEF | Clark | 41 hr |
| Jul 17, 5:02 PM PDT | Flash Flood Warning | VEF | Mohave | 3 hr |
| Jul 17, 6:57 PM PDT | Areal Flood Advisory | VEF | Mohave | 3 hr |
| Jul 17, 7:02 PM PDT | Areal Flood Advisory | VEF | Mohave | 3 hr |
| Jul 17, 7:19 PM PDT | Severe Thunderstorm Warning | VEF | Mohave | 56 min |
| Jul 17, 8:05 PM PDT | Areal Flood Advisory | VEF | Mohave | 3 hr |
| Jul 17, 8:09 PM PDT | Severe Thunderstorm Warning | VEF | Mohave | 35 min |
| Jul 18, 1:59 PM PDT | Flash Flood Warning | VEF | Mohave | 5 hr |
| Jul 18, 2:18 PM PDT | Flash Flood Warning | VEF | Mohave | 3 hr |
| Jul 18, 2:57 PM PDT | Flash Flood Warning | VEF | Mohave | 5 hr |
Nearby
Severe Thunderstorm Warnings in Nevada, 2017Severe Thunderstorm Warnings in Arizona, 2017Every severe thunderstorm 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.