Alert archive / Nevada / Flash Flood Watches in 2007

Flash Flood Watch 5, NWS Las Vegas, NV

July 25, 2007Clark County, Nevada; San Bernardino County, California; Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood watch at Jul 25, 2007, 9:56 AM PDT for Clark County, Nevada; San Bernardino County, California; Mohave County, Arizona. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued
Jul 25, 2007, 9:56 AM PDT (16:56 UTC)
Expired
Jul 25, 2007, 9:00 PM PDT
In force
11 hr
Issued by
NWS Las Vegas, NV
Flood severity
None

Counties Mohave County, AZ, San Bernardino County, CA, Clark County, NV

The radar

The Las Vegas radar (KESX), 15 km from the middle of the area, began a volume at 16:59 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

Mercury/Desert R, NV (KDRA), launched 12:00Z, 4.9 hours before the alert went out and 147 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-pSkew-T log-p diagram, Mercury/Desert R, NV at 12:00Z on 2007-07-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 133 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Mercury/Desert R, NV at 12:00Z on 2007-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
133 J/kg
Mixed-layer CIN
-159 J/kg
Mixed-layer LCL
1881 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
32 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch 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 flash flood watch went out at Jul 25, 2:45 AM PDT, 7 hours 11 minutes earlier.

Area forecast discussion, Jul 25, 2:45 AM PDT, 7 hours 11 minutes before
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Hazardous weather outlook, Jul 25, 3:47 AM PDT, 6 hours 9 minutes before
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In the hours before

Local storm report, Jul 25, 8:44 AM PDT, 1 hour 12 minutes before
PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE LAS VEGAS NV
844 AM PDT WED JUL 25 2007

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0630 PM     FLASH FLOOD      12 NE HUALAPAI PEAK     35.21N 113.77W
07/23/2007                   MOHAVE             AZ   TRAINED SPOTTER

            SPOTTER REPORTED 6 TENTHS OF AN INCH IN 10 MINUTES AND 1
            INCH IN 45 MINUTES.

1030 PM     FLASH FLOOD      HENDERSON               36.03N 115.00W
07/23/2007                   CLARK              NV   TRAINED SPOTTER

            TRAINED SPOTTER REPORTED MINOR FLOODING NEAR THE
            INTERSECTION OF RUSSELL ROAD AND INTERSTATE 515. REPORTED
            BETWEEN A QUARTER AND HALF AN INCH OF WATER OVER THE ROAD
            WITH ISOLATED SECTIONS OF UP TO AN INCH.

0140 PM     FLASH FLOOD      PEACH SPRINGS           35.53N 113.43W
07/24/2007                   MOHAVE             AZ   TRAINED SPOTTER

            EXCESSIVE STORM RUNOFF CROSSING ROUTE 66 NEAR PEACH
            SPRINGS.

0140 PM     FLASH FLOOD      PEACH SPRINGS           35.53N 113.43W
07/24/2007                   MOHAVE             AZ   TRAINED SPOTTER

            EXCESSIVE STORM RUNOFF CROSSING ROUTE 66 NEAR PEACH
            SPRINGS.

0750 PM     FLASH FLOOD      4 WSW GOLDEN VALLEY     35.21N 114.30W
07/24/2007                   MOHAVE             AZ   TRAINED SPOTTER

            SPOTTER REPOR 1.51 INCHES OF RAIN IN ONE HOUR. PUBLIC
            REPORTS WATER UP TO DOOR OF A HOME. MANY REPORTS OF CARS
            STUCK IN WASHES. THREE FEET OF WATER IN SACRAMENTO WASH.

&&

81

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 25, 2:41 PM PDTFlash Flood WarningVEFClark2 hr
Jul 25, 2:41 PM PDTFlash Flood WarningVEFClark94 min
Jul 25, 3:34 PM PDTSevere Thunderstorm WarningVEFClark28 min
Jul 24, 5:01 PM PDTFlash Flood WarningVEFSan Bernardino44 min
Jul 25, 12:54 PM PDTFlash Flood WarningVEFSan Bernardino2 hr
Jul 25, 3:00 PM PDTFlash Flood WarningVEFSan Bernardino2 hr
Jul 25, 3:53 PM PDTSevere Thunderstorm WarningVEFSan Bernardino67 min
Jul 24, 7:13 PM PDTFlash Flood WarningVEFMohave2 hr
Jul 25, 1:04 PM PDTFlash Flood WarningVEFMohave116 min
Jul 25, 1:37 PM PDTFlash Flood WarningVEFMohave113 min
Jul 25, 3:13 PM PDTFlash Flood WarningVEFMohave92 min
Jul 25, 4:15 PM PDTFlash Flood WarningVEFMohave90 min
Jul 25, 4:24 PM PDTSevere Thunderstorm WarningVEFMohave51 min

Nearby

Flash Flood Watches in Nevada, 2007Flash Flood Watches in California, 2007Flash Flood Watches in Arizona, 2007Every flash flood watch in 2007

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.