

000 

WGUS56 KSGX 251908

FFWSGX

CAC065-073-252300-

/O.NEW.KSGX.FF.W.0044.080825T1908Z-080825T2300Z/

/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/



BULLETIN - EAS ACTIVATION REQUESTED

FLASH FLOOD WARNING

NATIONAL WEATHER SERVICE SAN DIEGO CA

1208 PM PDT MON AUG 25 2008



THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A



* FLASH FLOOD WARNING FOR...

  WESTERN RIVERSIDE COUNTY IN SOUTHWEST CALIFORNIA...

  THIS INCLUDES THE CITIES OF...PALM SPRINGS...INDIO...

  EASTERN SAN DIEGO COUNTY IN SOUTHWEST CALIFORNIA...

  THIS INCLUDES THE CITY OF BORREGO SPRINGS...



* UNTIL 400 PM PDT



* AT 1159 AM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED

  FLASH FLOODING FROM A THUNDERSTORM OVER THE WARNED AREA.



* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ANZA...

  VALLE VISTA...RANCHO MIRAGE...PALM DESERT COUNTRY...PALM DESERT...

  CATHEDRAL CITY...BEAUMONT AND BANNING



THE WATERSHEDS BURNED LAST FALL ARE PARTICULARLY SUSCEPTIBLE TO FLASH

FLOODS AND DEBRIS FLOWS DURING RAINSTORMS. A SHORT PERIOD OF EVEN

MODERATE RAINFALL ON A BURNED WATERSHED CAN LEAD TO DEBRIS FLOWS.

RAINFALL THAT IS NORMALLY ABSORBED INTO HILLSLOPE SOILS CAN RUN OFF

ALMOST INSTANTLY AFTER VEGETATION HAS BEEN REMOVED BY WILDFIRE. THIS

CAUSES MUCH GREATER AND MORE RAPID RUNOFF THAN IS NORMAL FROM CREEKS

AND DRAINAGE AREAS. THE HIGHLY ERODIBLE SOILS IN A BURN SCAR ALLOW

FLOOD WATERS TO ENTRAIN LARGE AMOUNTS OF ASH, MUD...BOULDERS...AND

UNBURNED VEGETATION. WITHIN THE BURNED AREA AND DOWNSTREAM...THE

FORCE OF RUSHING WATER...SOIL AND ROCK CAN DESTROY CULVERTS...

BRIDGES...ROADWAYS AND BUILDINGS...POTENTIALLY CAUSING INJURY OR

DEATH.



EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL

CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE

BANKS OF CREEKS AND STREAMS.



LAT...LON 3363 11687 3396 11700 3395 11641 3392 11630

      3392 11626 3384 11618 3365 11617 3319 11629

      3265 11627 3260 11673



$$



ECC

