Alert archive / Nevada / Flash Flood Warnings in 2012

Flash Flood Warning 153, NWS Las Vegas, NV

August 22, 2012Clark County, Nevada

NWS Las Vegas, NV issued this flash flood warning at Aug 22, 2012, 10:53 AM PDT for Clark County, Nevada. It was in force for 4 hr. 10 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: Aug 22, 2012, 10:53 AM PDT (17:53 UTC)
Expired: Aug 22, 2012, 3:15 PM PDT
In force: 4 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), 53 km from the middle of the area, began a volume at 17:53 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
Aug 22, 11:23 AM PDT	FLASH FLOOD	Henderson, NV	THE CITY OF HENDERSON REPORTS THAT THE FOLLOWING INTERSECTIONS IN HENDERSON ARE CLOSED DUE TO FLOODING...SUNRIDGE HEIGHTS AT SEVEN HILLS...ANNABELLE AT WARM SPRINGS...AND...SUNSET AT ARROYO GRANDE.
Aug 22, 11:30 AM PDT	HEAVY RAIN 0.5	4 Ne Las Vegas, NV	14000 CUSTOMERS LOST POWER IN NORTHEAST LAS VEGAS DUE TO THE WEATHER. ANOTHER 3000 CUSTOMERS LOST POWER IN OTHER NEIGHBORHOODS IN THE LAS VEGAS VALLEY.
Aug 22, 11:30 AM PDT	HEAVY RAIN 1.65	3 S Las Vegas Strip, NV	SEVERAL INCHES OF WATER FLOODED VARIOUS PARTS OF LAS VEGAS BOULEVARD SOUTH MAINLY IN THE END LANES. NUMEROUS VEHICLES WERE STUCK IN FLOODWATERS. MANY VEHICLES WERE SUBMERGED IN FLOODWATERS THROUGHOUT THE SOUTH END OF THE LAS VEGAS VALLEY. 21 SWIFTWATER RESCUES
Aug 22, 11:32 AM PDT	FLASH FLOOD	Sloan, NV	REPORT OF UP TO 1 FOOT OF WATER RUNNING DOWN ROADWAY IN SLOAN.
Aug 22, 11:41 AM PDT	FLASH FLOOD	2 Ene Green Valley, NV	* 1 FATAL * THE CLARK COUNTY CORONER OFFICE CONFIRMED A 17 YEAR OLD BOY DIED AFTER HE FELL INTO A WASH NEAR STEPHANIE AND SUNSET IN HENDERSON. HIS BODY WAS FOUND ON AUGUST 24TH IN THE WETLANDS WEST OF BROADBENT BOULEVARD.
Aug 22, 12:19 PM PDT	HEAVY RAIN 1.5	3 Ssw Summerlin, NV	TRAINED SPOTTER REPORTED 1.50 INCHES OF RAIN SINCE 8 AM PDT THIS MORNING.
Aug 22, 12:39 PM PDT	FLASH FLOOD	4 Nw Henderson, NV	6 INCHES OF FLOWING WATER WITH MUD AND ROCKS AT THE INTERSECTION OF POLARIS AVE AND SERENE AVE.
Aug 22, 3:01 PM PDT	FLASH FLOOD	2 Ssw Henderson Executi, NV	HENDERSON AIRPORT RD FROM THE TERMINAL TO VOLUNTEER BLVD HAS BEEN CLOSED DUE TO FLASH FLOODING.
Aug 22, 3:15 PM PDT	FLASH FLOOD	1 Wnw Henderson, NV	A CHURCH LOCATED AT CACTUS AND BERMUDA WAS DAMAGED WHEN FLOOD WATERS ENTERED THE BUILDING. 3 FEET OF WATER ENTERED THE CHURCH CAUSING OVER 500,000 DOLLARS IN DAMAGE.
Aug 22, 3:15 PM PDT	FLASH FLOOD	1 Wnw Henderson Executi, NV	A CHURCH LOCATED AT CACTUS AND BERMUDA WAS DAMAGED WHEN FLOOD WATERS ENTERED THE BUILDING.

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, 5.9 hours before the alert went out and 45 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: 296 J/kg
Mixed-layer CIN: -130 J/kg
Mixed-layer LCL: 1290 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 103 m²/s²
0-3 km storm-relative helicity: 176 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 3.4

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

256 
WGUS55 KVEF 221753
FFWVEF
NVC003-222045-
/O.NEW.KVEF.FF.W.0153.120822T1753Z-120822T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
1053 AM PDT WED AUG 22 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL CLARK COUNTY IN SOUTHERN NEVADA...

* UNTIL 145 PM PDT.

* AT 1044 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUES 
TO INDICATE NUMEROUS THUNDERSTORMS MOVING ACROSS THE LAS VEGAS 
VALLEY PRODUCING VERY HEAVY RAIN. THE INTENSE RAIN ASSOCIATED WITH 
THESE STORMS IS AND WILL CONTINUE TO RESULT IN LOCALIZED AREAS OF 
FLASH FLOODING ACROSS THE LAS VEGAS VALLEY THROUGH AT LEAST 145 PM 
PDT TODAY.

* LOCATIONS IMPACTED INCLUDE...THE LAS VEGAS VALLEY...INCLUDING 
HENDERSON...DOWNTOWN LAS VEGAS...SUMMERLIN...NORTH LAS 
VEGAS...SPRING VALLEY...MCCARRAN INTERNATIONAL AIRPORT...THE 
STRIP...NORTH LAS VEGAS AIRPORT...EAST LAS VEGAS...SAM BOYD 
STADIUM...LONE MOUNTAIN...CENTENNIAL HILLS...NELLIS AIR FORCE BASE 
AND ALIANTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND UNDERPASSES...
AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. FLASH FLOODING IS
NATURES NUMBER ONE KILLER. NEVER TRY TO CROSS A FLOODED ROADWAY OR
WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3633 11535 3633 11490 3613 11490 3596 11491
      3590 11514 3598 11535

$$

KENNEDY

4 follow-up statements

242 
WGUS75 KVEF 221839
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1139 AM PDT WED AUG 22 2012

NVC003-222045-
/O.CON.KVEF.FF.W.0153.000000T0000Z-120822T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
1139 AM PDT WED AUG 22 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 145 PM PDT FOR
CENTRAL CLARK COUNTY...

NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO INDICATE 
WIDESPREAD MODERATE TO HEAVY RAIN ACROSS THE LAS VEGAS VALLEY...WITH 
ADDITIONAL THUNDERSTORMS WITH RAINFALL RATES EXCEEDING ONE INCH PER 
HOUR EXPECTED TO MOVE FROM SOUTHWEST TO NORTHEAST ACROSS THE LAS 
VEGAS VALLEY THROUGH 1230 PM TODAY. THE ENTIRE VALLEY WILL SEE 
CONTINUED MODERATE TO HEAVY RAIN...BUT THE FOCUS OF THIS CLUSTER OF 
STORMS WILL BE OVER THE SOUTH AND EASTERN HALF OF THE VALLEY. 

LATEST SURFACE OBSERVATIONS ACROSS THE VALLEY SHOW BETWEEN ONE AND 2 
INCHES OF RAIN ON AVERAGE HAVE ALREADY FALLEN AND THE ADDITIONAL 
HEAVY RAIN EXPECTED WILL SIGNIFICANTLY ADD TO THE FLASH FLOOD THREAT.

LOCATIONS IMPACTED INCLUDE...THE LAS VEGAS VALLEY...INCLUDING 
HENDERSON...DOWNTOWN LAS VEGAS...SLOAN...SUMMERLIN...NORTH LAS 
VEGAS...SPRING VALLEY...MCCARRAN INTERNATIONAL AIRPORT...THE 
STRIP...NORTH LAS VEGAS AIRPORT...EAST LAS VEGAS...SAM BOYD 
STADIUM...LONE MOUNTAIN...CENTENNIAL HILLS...NELLIS AIR FORCE BASE 
AND ALIANTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND 
UNDERPASSES...AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. 
RESIDENTS IN THE AREA SHOULD BE ALERT TO THE POSSIBILITY OF RAPIDLY 
RISING WATER AND BE PREPARED TO EVACUATE IF NECESSARY. NEVER TRY TO 
CROSS A FLOODED ROADWAY OR WALK THROUGH FLOODWATERS. MOST FLASH FLOOD
RELATED DEATHS OCCUR FROM DRIVERS ATTEMPTING TO CROSS FLOODED 
ROADWAYS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3633 11535 3633 11490 3613 11490 3596 11491
      3590 11514 3598 11535

$$

KENNEDY

968 
WGUS75 KVEF 221934
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
1234 PM PDT WED AUG 22 2012

NVC003-222045-
/O.CON.KVEF.FF.W.0153.000000T0000Z-120822T2045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
1234 PM PDT WED AUG 22 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 145 PM PDT FOR
CENTRAL CLARK COUNTY...

AT 1219 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE WIDESPREAD MODERATE TO HEAVY RAIN ACROSS THE LAS VEGAS 
VALLEY...WITH ADDITIONAL MODERATE RAIN EXPECTED THROUGH AT LEAST 130 
PM TODAY. THE FOCUS CONTINUES TO BE OVER THE SOUTH AND EASTERN HALF 
OF THE VALLEY...WHERE AN ADDITIONAL HALF TO ONE INCH HAS FALLEN OVER 
THE PAST HOUR...BRINGING TOTALS SO FAR TODAY TO BETWEEN TWO AND 
THREE INCHES AT LOCATIONS HARDEST HIT.  

FLOODING IS CURRENTLY OCCURRING AT MANY LOCATIONS AND INTERSECTIONS 
ACROSS THE VALLEY...AT LEAST FOUR SWIFT WATER RESCUES HAVE BEEN 
NEEDED THUS FAR TODAY...AND DELAYS AT MCCARRAN INTERNATIONAL ARE 
CURRENTLY AVERAGING 90 MINUTES DUE TO THE WEATHER.

LOCATIONS IMPACTED INCLUDE...THE LAS VEGAS VALLEY...INCLUDING 
HENDERSON...DOWNTOWN LAS VEGAS...SLOAN...SUMMERLIN...NORTH LAS 
VEGAS...SPRING VALLEY...MCCARRAN INTERNATIONAL AIRPORT...THE 
STRIP...NORTH LAS VEGAS AIRPORT...EAST LAS VEGAS...SAM BOYD 
STADIUM...LONE MOUNTAIN...CENTENNIAL HILLS...NELLIS AIR FORCE BASE 
AND ALIANTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND UNDERPASSES...
AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. FLASH FLOODING IS
NATURES NUMBER ONE KILLER. NEVER TRY TO CROSS A FLOODED ROADWAY OR
WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3633 11535 3633 11490 3613 11490 3596 11491
      3590 11514 3598 11535

$$

KENNEDY

347 
WGUS55 KVEF 222010
FFWVEF
NVC003-222215-
/O.EXT.KVEF.FF.W.0153.000000T0000Z-120822T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LAS VEGAS NV
110 PM PDT WED AUG 22 2012

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  CENTRAL CLARK COUNTY IN SOUTHERN NEVADA...

* UNTIL 315 PM PDT.

* AT 103 PM PDT...MODERATE RAIN IS EXPECTED TO CONTINUE ACROSS THE 
LAS VEGAS VALLEY THROUGH AT LEAST 200 PM...AND WITH FLOODING ALREADY 
OCCURRING AT MANY LOCATIONS AND INTERSECTIONS ACROSS THE 
VALLEY...ANY ADDITIONAL RAIN WILL SUPPORT CONTINUED LOCALIZED AREAS 
OF FLASH FLOODING ACROSS THE LAS VEGAS VALLEY. 

LOCATIONS IMPACTED INCLUDE...THE LAS VEGAS VALLEY...INCLUDING 
HENDERSON...DOWNTOWN LAS VEGAS...SLOAN...SUMMERLIN...NORTH LAS 
VEGAS...SPRING VALLEY...MCCARRAN INTERNATIONAL AIRPORT...THE 
STRIP...NORTH LAS VEGAS AIRPORT...EAST LAS VEGAS...SAM BOYD 
STADIUM...LONE MOUNTAIN...CENTENNIAL HILLS...NELLIS AIR FORCE BASE 
AND ALIANTE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

FLASH FLOODING IS EXPECTED ON AREA ROADWAYS...AROUND UNDERPASSES...
AND IN NORMALLY DRY WASHES AND LOW LYING AREAS. FLASH FLOODING IS
NATURES NUMBER ONE KILLER. NEVER TRY TO CROSS A FLOODED ROADWAY OR
WALK THROUGH FLOODWATERS. TURN AROUND...DONT DROWN!

REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS NATIONAL
WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER HASHTAG...
NWSVEGAS.

&&

LAT...LON 3633 11535 3633 11490 3613 11490 3596 11491
      3590 11514 3598 11535

$$

KENNEDY

626 
WGUS75 KVEF 222212
FFSVEF

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
312 PM PDT WED AUG 22 2012

NVC003-222215-
/O.EXP.KVEF.FF.W.0153.000000T0000Z-120822T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CLARK NV-
312 PM PDT WED AUG 22 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 315 PM PDT FOR CENTRAL
CLARK COUNTY...

WHILE ADDITIONAL RAINFALL IS LIKELY THE REMAINDER OF THE DAY AND 
OVERNIGHT ACROSS THE LAS VEGAS VALLEY...WIDESPREAD MODERATE TO HEAVY 
RAINFALL HAS LARGELY ENDED. THEREFORE...THE FLASH FLOOD WARNING FOR 
THE LAS VEGAS VALLEY WILL BE ALLOWED TO EXPIRE AT 315 PM TODAY. 
ALTHOUGH THE THREAT OF SIGNIFICANT ADDITIONAL RAINFALL HAS 
ENDED...IT WILL LIKELY BE SEVERAL HOURS BEFORE RUNNING WATER IN 
WASHES BEGIN TO RECEDE...AND ROADWAYS...INTERSECTIONS...AND 
LOCALIZED AREAS PRONE TO FLOODING WILL LIKELY STILL BE IMPACTED 
THROUGH 500 PM TODAY.

YOU CAN REPORT FLOODING BY POSTING YOUR REPORT TO THE LAS VEGAS 
NATIONAL WEATHER SERVICE FACEBOOK PAGE...OR BY USING THE TWITTER 
HASHTAG...NWSVEGAS.


LAT...LON 3633 11535 3633 11490 3613 11490 3596 11491
      3590 11514 3598 11535

$$

KENNEDY

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 21, 6:10 PM PDT	Flash Flood Warning	VEF	Clark, Lincoln	2 hr
Aug 21, 6:47 PM PDT	Flash Flood Warning	VEF	Lincoln	118 min
Aug 22, 12:12 AM PDT	Flash Flood Warning	VEF	Clark	2 hr
Aug 22, 2:35 AM PDT	Flash Flood Warning	VEF	Clark	115 min
Aug 22, 8:22 AM PDT	Areal Flood Advisory	VEF	Clark	9 hr
Aug 22, 9:19 AM PDT	Areal Flood Advisory	VEF	Clark, Lincoln, Nye	3 hr
Aug 22, 9:20 AM PDT	Flash Flood Warning	VEF	Clark	101 min
Aug 22, 9:34 AM PDT	Flash Flood Warning	VEF	Clark	116 min
Aug 22, 9:59 AM PDT	Flash Flood Warning	VEF	Clark	59 min
Aug 22, 10:05 AM PDT	Flash Flood Warning	VEF	Esmeralda	76 min
Aug 22, 12:12 PM PDT	Flash Flood Warning	VEF	Clark	4 hr
Aug 22, 12:33 PM PDT	Flash Flood Warning	VEF	Clark	117 min
Aug 22, 2:40 PM PDT	Areal Flood Advisory	VEF	Clark	6 hr
Aug 22, 3:43 PM PDT	Flash Flood Warning	VEF	Clark	2 hr

Nearby

Flash Flood Warnings in Nevada, 2012 Every flash flood warning in 2012

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.