Alert archive / Arizona / Flash Flood Watches in 2010

Flash Flood Watch 2, NWS Las Vegas, NV

July 31, 2010Mohave County, Arizona

NWS Las Vegas, NV issued this flash flood watch at Jul 31, 2010, 3:25 AM MST for Mohave County, Arizona. It took effect at Jul 31, 2010, 12:00 PM MST. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued: Jul 31, 2010, 3:25 AM MST (10:25 UTC)
In effect from: Jul 31, 2010, 12:00 PM MST
Expired: Jul 31, 2010, 8:00 PM MST
In force: 8 hr
Issued by: NWS Las Vegas, NV
Flood severity: None

County Mohave County, AZ

The radar

The Las Vegas radar (KESX), 102 km from the middle of the area, began a volume at 10:29 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

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 10.4 hours before the alert went out and 185 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: 466 J/kg
Mixed-layer CIN: -6 J/kg
Mixed-layer LCL: 592 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: -46 m²/s²
0-3 km storm-relative helicity: 96 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 31, 3:20 AM MST, 5 minutes earlier.

Area forecast discussion, Jul 31, 3:20 AM MST, 5 minutes before

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Hazardous weather outlook, Jul 30, 6:31 AM MST, 20 hours 54 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LAS VEGAS NV
631 AM PDT FRI JUL 30 2010

AZZ001>003-036-CAZ524-526-527-NVZ015>022-310700-
NORTHWEST PLATEAU-LOWER COLORADO RIVER VALLEY-NORTHWEST DESERTS-
LAKE MEAD NATIONAL RECREATION AREA-EASTERN MOJAVE DESERT-
CADIZ BASIN-SAN BERNARDINO COUNTY-UPPER COLORADO RIVER VALLEY-
LINCOLN COUNTY-NORTHEAST CLARK COUNTY-
WESTERN CLARK AND SOUTHERN NYE COUNTY-SHEEP RANGE-
SPRING MOUNTAINS-LAS VEGAS VALLEY-SOUTHERN CLARK COUNTY-
631 AM PDT FRI JUL 30 2010 /631 AM MST FRI JUL 30 2010/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST
ARIZONA...CALIFORNIA AND SOUTHERN NEVADA.

.DAY ONE...TODAY AND TONIGHT

AN INCREASE IN MOISTURE WILL PROVIDE ADDITIONAL FUEL FOR THUNDERSTORMS
TO DEVELOP...ESPECIALLY DURING THE AFTERNOON AND EVENING. THE AIR
MASS IS MOST UNSTABLE OVER MOHAVE COUNTY ARIZONA AND THUNDERSTORMS
WILL BE MORE PRONE TO PRODUCE HEAVY RAIN AND THE POTENTIAL FOR
LOCALIZED FLASH FLOODING THERE. ALTHOUGH THUNDERSTORM COVERAGE
DECREASES FROM THE COLORADO RIVER VALLEY WESTWARD...SOME STORMS
COULD STILL PRODUCE HEAVY RAINFALL AND LOCALIZED FLASH FLOODING
THIS AFTERNOON AND EVENING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

MOIST AND UNSTABLE AIR WILL REMAIN GENERALLY OVER THE SAME AREAS
THROUGH THE WEEKEND PROVIDING ISOLATED TO SCATTERED
THUNDERSTORMS WITH THE POTENTIAL FOR HEAVY RAIN AND LOCALIZED
FLASH FLOODING...ESPECIALLY OVER NORTHWEST ARIZONA.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. HOWEVER...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

CAZ519>523-525-NVZ014-310700-
EASTERN SIERRA SLOPES-OWENS VALLEY-WHITE MOUNTAINS OF INYO COUNTY-
DEATH VALLEY NATIONAL PARK-WESTERN MOJAVE DESERT-MORONGO BASIN-
ESMERALDA AND CENTRAL NYE COUNTY-
631 AM PDT FRI JUL 30 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CALIFORNIA AND
SOUTHERN NEVADA.

.DAY ONE...TODAY AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

JA

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 30, 5:23 PM MST	Severe Thunderstorm Warning	VEF	Lincoln	19 min
Jul 30, 6:42 PM MST	Flash Flood Warning	VEF	Lincoln	2 hr
Jul 31, 1:28 PM MST	Areal Flood Advisory	VEF	Mohave	44 min
Jul 31, 2:09 PM MST	Areal Flood Advisory	VEF	Mohave	60 min
Jul 31, 3:07 PM MST	Flash Flood Warning	VEF	Mohave	113 min

Nearby

Flash Flood Watches in Arizona, 2010 Every flash flood watch in 2010

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.