BULLETIN – EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1053 PM CDT WED JUL 21 2010

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR…
LYON COUNTY IN NORTHWEST IOWA
NORTHERN LINCOLN COUNTY IN SOUTHEAST SOUTH DAKOTA
ROCK COUNTY IN SOUTHWEST MINNESOTA
SOUTHEASTERN MINNEHAHA COUNTY IN SOUTHEAST SOUTH DAKOTA

* UNTIL 500 AM CDT THURSDAY

* AT 1047 PM CDT…NATIONAL WEATHER SERVICE DOPPLER RADAR
INDICATED THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. ONE TO THREE INCHES OF RAINFALL IS EXPECTED OVER THE WARNED AREA OVER THE NEXT FEW HOURS RESULTING IN FLASH FLOODING…ESPECIALLY IN URBAN AREAS. THIS WARNING REPLACES THE PREVIOUS WARNING IN EFFECT.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE…CANTON…LUVERNE…ROCK RAPIDS…SIOUX FALLS…ALVORD…BEAVER CREEK…BLUE MOUNDS STATE PARK…BRANDON…CROOKS…DOON…GARRETSON…HARRISBURG…HILLS…INWOOD…LARCHWOOD…LENNOX…LESTER…PALISADES STATE PARK…ROWENA…TEA…VALLEY SPRINGS AND WORTHING.

AT 1050 PM…MANY ROADS IN SIOUX FALLS WERE REPORTED FLOODED.

PRECAUTIONARY/PREPAREDNESS ACTIONS…

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL CREEKS AND STREAMS…URBAN AREAS…HIGHWAYS…STREETS AND UNDERPASSES AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. DO NOT ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY.