The National Weather Service (San Diego) has issued a Flash Flood Watch for the Coachella Valley today from 2pm until 8pm. Conditions are favorable for thunderstorm development as the atmosphere is still moist and unstable.

copy of watch:

Flash Flood Watch - Coachella Valley (California)

Updated: Friday, August 15, 2008 11:18am PDT

FLASH FLOODS ARE POSSIBLE THIS AFTERNOON AND EVENING OVER THE
DESERT AREAS OF SOUTHWEST CALIFORNIA…

.MOIST AND UNSTABLE AIR MASS REMAINS OVER SOUTHWEST CALIFORNIA.
THE FOCUSING MECHANISMS FOR CONVECTION THIS AFTERNOON WILL BE
CENTERED ALONG A LINE FROM EAST OF DAGGETT SOUTH SOUTHEASTWARD
THROUGH JOHNSON VALLEY…DESERT HOT SPRINGS…PALM
SPRINGS…ACROSS THE SANTA ROSA MOUNTAINS TO BORREGO
SPRINGS…AQUA CALIENTE SPRINGS…AND JACUMBA. DURING THE EVENING
HOURS THIS LINE WILL SHIFT TO THE NORTHEAST. HEAVY RAINFALL IN
THUNDERSTORMS IS EXPECTED OVER THE MOUNTAINS THIS AFTERNOON. CREEKS
AND NORMALLY DRY WASHES DRAINING INTO THE DESERT AREAS MAY BECOME
FLOODED DURING THE LATE AFTERNOON AND EARLY EVENING HOURS.
RAINFALL AMOUNTS OVER THE DESERT FLOORS ARE EXPECTED TO RANGE FROM
A FEW HUNDREDTHS OF AN INCH TO A AROUND A HALF AN INCH.

CAZ060>062-160300-
/O.NEW.KSGX.FF.A.0010.080815T2100Z-080816T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
APPLE AND LUCERNE VALLEYS-COACHELLA VALLEY-
SAN DIEGO COUNTY DESERTS-
952 AM PDT FRI AUG 15 2008

…FLASH FLOOD WATCH IN EFFECT FROM 2 PM THIS AFTERNOON TO 8 PM
PDT THIS EVENING…

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A

* FLASH FLOOD WATCH FOR A PORTION OF SOUTHWEST CALIFORNIA…
INCLUDING THE FOLLOWING AREAS…APPLE AND LUCERNE VALLEYS…
COACHELLA VALLEY AND SAN DIEGO COUNTY DESERTS.

* FROM 2 PM THIS AFTERNOON TO 8 PM PDT THIS EVENING

* HEAVY RAINFALL FROM THUNDERSTORMS OVER THE MOUNTAINS MAY PRODUCE
FLASH FLOODING IN NORMALLY DRY WASHES LEADING FROM THE MOUNTAINS
TO THE DESERT FLOORS.

* MOTORISTS SHOULD PLAN ON ALTERNATIVE ROUTES THIS AFTERNOON AND
EVENING THAT AVOID ROADS THAT DIP DOWN INTO NORMALLY DRY WASHES.

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.

$$
Issuing Weather Forecast Office Homepage

Flash Flood Potential Index for today (Friday, 15th)

Flash Flood Potential Index

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