Issued by NWS Denver/Boulder, CO
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000 NOUS45 KBOU 231209 PNSBOU PUBLIC INFORMATION STATEMENT NATIONAL WEATHER SERVICE BOULDER COLORADO 600 AM MDT THU APR 23 2009 ...FLOOD AND FLASH FLOOD SAFETY... IN COLORADO...THERE ARE TWO DISTINCT TYPES OF FLOODING. WHEN THE SNOW BEGINS TO MELT IN THE HIGH COUNTRY...RIVERS BEGIN TO RISE. FLOODING ALONG RIVERS AND STREAMS CAN OCCUR WITH A VERY RAPID SNOW MELT...OR FROM THUNDERSTORM RAINS COMBINING WITH THE RUNOFF FROM MELTING SNOW. A FLASH FLOOD REFERS TO A DANGEROUS SUDDEN RISE IN WATER ALONG A CREEK...WASH...RIVER...OR OVER A NORMALLY DRY LAND AREA. FLASH FLOODS RESULT FROM HEAVY RAINFALL...RIVER ICE JAMS...AND DAM OR LEVEE FAILURES. FLASH FLOODS CAN OCCUR WITHIN A FEW MINUTES OR HOURS...AND CAN MOVE AT SURPRISINGLY HIGH SPEEDS...STRIKING WITH LITTLE WARNING. FLASH FLOODS ARE QUITE DESTRUCTIVE BECAUSE OF THE FORCE OF THE MOVING WATER...AND THE DEBRIS THAT ACCUMULATES IN FLOOD WATERS...SUCH AS TREES AND BOULDERS... WHICH CAN DESTROY ROADWAYS...BRIDGES AND BUILDINGS. RAIN WEAKENED SOILS CAN ALSO RESULT IN MUD SLIDES CAPABLE OF CLOSING ROADWAYS. COLORADO IS VERY SUSCEPTIBLE TO FLASH FLOODING...AND FLASH FLOODS OCCUR SOMEWHERE IN THE STATE EVERY YEAR. THE NATIONAL WEATHER SERVICE WILL DISCUSS FLOOD AND FLASH FLOOD POTENTIAL IN DAILY HAZARDOUS WEATHER OUTLOOKS AND IN THE WEATHER STORY ON NATIONAL WEATHER SERVICE WEBSITES. ON DAYS WITH A HIGH THREAT FOR FLOODING YOU MAY HEAR... A FLASH FLOOD OR FLOOD WATCH...WHICH MEANS THAT FLASH FLOODING OR FLOODING IS POSSIBLE WITHIN THE WATCH AREA. YOU SHOULD REMAIN ALERT AND BE READY TO EVACUATE WITHIN A SHORT TIME. A FLOOD WARNING...WHICH MEANS THAT FLOODING IS IMMINENT OR HAS BEEN REPORTED ALONG A RIVER. WHEN A FLOOD WARNING IS ISSUED TAKE PRECAUTIONS TO PROTECT PROPERTY. A FLASH FLOOD WARNING...WHICH MEANS THAT FLASH FLOODING HAS BEEN REPORTED OR IS IMMINENT. WHEN A FLASH FLOOD WARNING IS ISSUED FOR YOUR AREA...ACT QUICKLY. IF ADVISED TO EVACUATE...DO SO IMMEDIATELY. GO TO HIGHER GROUND OR CLIMB TO SAFETY BEFORE ACCESS IS CUT OFF BY FLOOD WATERS. YOU MAY NOT ALWAYS HAVE A WARNING THAT THESE DEADLY SUDDEN FLOODS ARE COMING...SO YOU NEED TO KNOW SOME BASIC FLASH FLOOD SAFETY RULES... DO NOT CAMP OR PARK YOUR VEHICLE ALONG CREEKS AND WASHES... ESPECIALLY DURING THREATENING CONDITIONS. IF YOU ARE NEAR A RIVER...BE AWARE OF WATER LEVELS AND BE PREPARED TO GO TO HIGHER GROUND IF RIVER LEVELS RISE. DO NOT ENTER AREAS THAT ARE ALREADY FLOODED. DO NOT TRY TO CROSS A FLOWING CREEK ON FOOT WHEN THE WATER IS AT OR ABOVE YOUR KNEES. IF WALKING OR FISHING ALONG A RIVER...BE AWARE THAT EROSION FROM SWIFT FLOWING WATER CAN CAUSE RIVER BANKS TO COLLAPSE. NEVER ALLOW CHILDREN TO PLAY AROUND HIGH WATER...STORM DRAINS...VIADUCTS...OR ARROYOS. BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO SEE FLOOD DANGERS. NEARLY HALF OF ALL FLASH FLOOD FATALITIES ARE VEHICLE RELATED. DO NOT ENTER A FLOODED ROADWAY...INSTEAD TURN AROUND DO NOT DROWN. IN RAPIDLY RISING WATERS...BACKING UP AWAY FROM WITH WATER MAY BE SAFER. ONE TO TWO FEET OF WATER WILL CARRY AWAY MOST VEHICLES AND YOU ALSO CANNOT TELL IF THE ROAD IS DAMAGED BENEATH THE WATER. MORE INFORMATION ON FLASH FLOOD SAFETY IS AVAILABLE AT HTTP://TADD.WEATHER.GOV DURING FLASH FLOOD SEASON...AND YEAR ROUND...KEEP TRACK OF THE LATEST WEATHER INFORMATION. YOU CAN RECEIVE THE LATEST FORECASTS AND IMMEDIATE NOTIFICATION OF WARNINGS ON NOAA WEATHER RADIO ALL HAZARDS ...OR CHECK CURRENT FORECASTS...WATCHES...AND WARNINGS ON THE WEB AT HTTP://WWW.WEATHER.GOV SEVERE WEATHER AWARENESS WEEK CONTINUES THROUGH THIS SATURDAY. BOB GLANCY WARNING COORDINATION METEOROLOGIST NOAA NATIONAL WEATHER SERVICE BOULDER COLORADO