Flash flood watch in effect until 8 pm
Deep monsoonal moisture could lead to heavy showers and thunderstorms this afternoon and evening in the mountains, deserts, and inland valleys.
Lightning, small hail, and gusty downdraft winds could accompany storms as well.
The National Weather Service in San Diego has issued a Flash Flood Watch for the deserts, mountains, and inland valleys until 8 pm Thursday.
The National Weather Service in Las Vegas has issued a Flash Flood Watch for the high desert along and north of Highway 62 until 8 pmThursday.
The full text warnings have been copied below.
Flash Flood Watch
FLOOD WATCH
NATIONAL WEATHER SERVICE SAN DIEGO CA
816 PM PDT WED JUL 29 2015
…FLASH FLOOD WATCH FOR THE MOUNTAINS…DESERTS AND THE INLAND
EMPIRE FOR THURSDAY…
.A SIGNIFICANT SURGE OF MONSOON MOISTURE AND HIGH INSTABILITY WILL
LIKELY RESULT IN HEAVY SHOWERS AND THUNDERSTORMS FOR THE
MOUNTAINS…DESERTS AND THE INLAND EMPIRE ON THURSDAY…RESULTING
IN AN INCREASED THREAT FOR FLASH FLOODING IN THOSE AREAS. SHOWERS
AND ISOLATED THUNDERSTORMS SHOULD START TO MOVE INTO THE AREA
EARLY THURSDAY MORNING AS AN UPPER LEVEL DISTURBANCE MOVES
THROUGH THE REGION. THEN…DAY-TIME HEATING WITH DECREASING CLOUD
COVER SHOULD LEAD TO THUNDERSTORMS DEVELOPING IN THE MOUNTAINS AND
DESERTS DURING THE LATE MORNING AND AFTERNOON HOURS…AND ALSO
INTO THE INLAND EMPIRE. THE THUNDERSTORM AND FLASH FLOOD THREAT
SHOULD DIMINISH BY LATE EVENING.
SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-
SAN BERNARDINO COUNTY MOUNTAINS-RIVERSIDE COUNTY MOUNTAINS-
SAN DIEGO COUNTY MOUNTAINS-APPLE AND LUCERNE VALLEYS-
COACHELLA VALLEY-SAN DIEGO COUNTY DESERTS-
SAN GORGONIO PASS NEAR BANNING-
816 PM PDT WED JUL 29 2015
…FLASH FLOOD WATCH IN EFFECT FROM 3 AM PDT THURSDAY THROUGH
THURSDAY EVENING…
THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A
* FLASH FLOOD WATCH FOR PORTIONS OF SOUTHWEST
CALIFORNIA…INCLUDING THE FOLLOWING AREAS…SAN GORGONIO PASS
NEAR BANNING…APPLE AND LUCERNE VALLEYS…COACHELLA
VALLEY…RIVERSIDE COUNTY MOUNTAINS…SAN BERNARDINO COUNTY
MOUNTAINS…SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE
INLAND EMPIRE…SAN DIEGO COUNTY DESERTS AND SAN DIEGO COUNTY
MOUNTAINS.
* FROM 3 AM PDT THURSDAY THROUGH THURSDAY EVENING.
* PLENTIFUL MONSOON MOISTURE AND INSTABILITY WILL BRING THE CHANCE
FOR THUNDERSTORMS PRODUCING HEAVY RAINFALL WHICH COULD RESULT IN
FLASH FLOODING FOR MOST OF THURSDAY. AN UPPER LEVEL DISTURBANCE
COULD BRING HEAVY RAINS AND THUNDERSTORMS EARLY THURSDAY
MORNING…AND THEN SLOWER MOVING THUNDERSTORMS ARE EXPECTED TO
DEVELOP OVER THE MOUNTAINS…DESERTS AND THE INLAND EMPIRE
DURING THE LATE MORNING AND AFTERNOON HOURS…AND PERSIST INTO
THE EARLY EVENING HOURS.
* RECENT BURN SCARS WILL BE PARTICULARLY SUSCEPTIBLE TO FLASH
FLOODING AND DEBRIS FLOWS.
PRECAUTIONARY/PREPAREDNESS ACTIONS…
A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING. FLASH FLOODING IS A VERY DANGEROUS SITUATION.
YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION
SHOULD FLASH FLOOD WARNINGS BE ISSUED.
Flash Flood Watch
FLOOD WATCH
NATIONAL WEATHER SERVICE LAS VEGAS NV
240 AM PDT THU JUL 30 2015
…FLASH FLOOD WATCH IN EFFECT FOR PARTS OF SOUTHEAST CALIFORNIA
AND CLARK COUNTY NEVADA TODAY…
.MONSOONAL MOISTURE ALONG WITH A DISTURBANCE IN THE ATMOSPHERE
MOVING NORTHWEST ACROSS SOUTHERN CALIFORNIA TODAY WILL HELP TO
TRIGGER SHOWERS AND THUNDERSTORMS. ANY STRONGER OR SLOWER MOVING
THUNDERSTORM ACTIVITY WILL BE CAPABLE OF PRODUCING HEAVY RAINFALL
WHICH COULD RESULT IN FLASH FLOODING.
EASTERN SIERRA SLOPES-OWENS VALLEY-WHITE MOUNTAINS OF INYO COUNTY-
DEATH VALLEY NATIONAL PARK-WESTERN MOJAVE DESERT-
EASTERN MOJAVE DESERT-MORONGO BASIN-CADIZ BASIN-SPRING MOUNTAINS-
RED ROCK CANYON-SOUTHERN CLARK COUNTY-
240 AM PDT THU JUL 30 2015
…FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THIS EVENING…
THE FLASH FLOOD WATCH CONTINUES FOR
* PORTIONS OF SOUTHEAST CALIFORNIA AND SOUTHERN NEVADA… INCLUDING
THE FOLLOWING AREAS…IN SOUTHEAST CALIFORNIA… CADIZ
BASIN…DEATH VALLEY NATIONAL PARK…EASTERN MOJAVE
DESERT…EASTERN SIERRA SLOPES…MORONGO BASIN…OWENS
VALLEY…WESTERN MOJAVE DESERT AND WHITE MOUNTAINS OF INYO COUNTY.
IN SOUTHERN NEVADA…SOUTHERN CLARK COUNTY AND THE SPRING
MOUNTAINS-RED ROCK CANYON.
* THROUGH THIS EVENING.
* SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS
PORTIONS OF SOUTHEAST CALIFORNIA AND FAR SOUTHERN NEVADA ON
THURSDAY ESPECIALLY FROM THE MID-MORNING HOURS INTO THE EARLY
EVENING HOURS.
* ANY STRONGER OR SLOWER MOVING THUNDERSTORMS COULD UNLEASH 1 TO
2 INCHES OF RAINFALL…WITH LOCALLY HIGHER AMOUNTS POSSIBLE IN
AN HOUR OR LESS. THIS COULD LEAD TO FLASH FLOODING ESPECIALLY
IF IT FALLS OVER ANY LOW LYING AREAS OR IN A WASH OR CANYON
THAT QUICKLY MOVES WATER TO A LOWER AREA.
* IMPACTS…ROADS COULD BE CLOSED DUE TO WATER FLOWING OVER THEM AS
WELL AS MUD AND ROCKS WASHING ONTO THEM. ROADWAY PAVEMENT MAY BE
WASHED AWAY. SOME DIRT AND SECONDARY GRAVEL ROADS COULD BE WASHED
OUT. RAPID RISES IN WASHES COULD ALSO OCCUR LEADING TO FLASH
FLOODING DOWNSTREAM. ANY BURN AREAS…SUCH AS THE CARPENTER 1 BURN
AREA ON MT CHARLESTON…COULD ALSO SEE DEBRIS FLOWS TAKE PLACE IF
HEAVY RAIN FALLS ON OR RUNS ONTO THE BURNED LANDSCAPE.
PRECAUTIONARY/PREPAREDNESS ACTIONS…
A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING. FLASH FLOODING IS A VERY DANGEROUS SITUATION.
YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION
SHOULD FLASH FLOOD WARNINGS BE ISSUED.
