AXUS71 KRNK 261530 DGTRNK NCC005-009-033-157-169-171-189-193-197-VAC005-009-011-017-019-021- 023-029-031-035-037-045-063-067-071-077-083-089-121-141-143-155- 161-163-173-185-197-515-530-580-590-640-678-680-690-750-770-775- WVC025-055-063-089-101530- DROUGHT INFORMATION STATEMENT NATIONAL WEATHER SERVICE BLACKSBURG VA 1130 AM EDT THU JUN 26 2008 ...SPORADIC JUNE RAINFALL SUSTAINS DROUGHT IN THE REGION... SYNOPSIS... JUNE RAINFALL HAS BEEN INCONSISTENT ACROSS THE REGION WITH POCKETS OF HEAVY RAINFALL AND AREAS WITH VERY LITTLE. DROUGHT CONDITIONS ARE ABOUT THE SAME OR SLIGHTLY WORSE THAN TWO WEEKS AGO ACROSS THE BLACKSBURG HYDROLOGIC SERVICE AREA (HSA). EXTREME DROUGHT CONTINUES OVER SEVERAL COUNTIES IN NORTH CAROLINA AND SEVERE DROUGHT HAS REACHED AS FAR NORTH AS SOUTHERN VIRGINIA. THE BLACKSBURG HSA COVERS 27 COUNTIES IN SOUTHWEST VIRGINIA... 4 IN EXTREME SOUTHEAST WEST VIRGINIA AND 9 IN NORTHWEST NORTH CAROLINA AND INCLUDES PORTIONS OF THE FOLLOWING RIVER BASINS: JAMES...ROANOKE...NEW...GREENBRIER...DAN...YADKIN...CLINCH AND HOLSTON. SUMMARY OF IMPACTS... THE U.S. DROUGHT MONITOR (USDM)... THE USDM ISSUED TODAY AND REFLECTING CONDITIONS THROUGH 8 AM ON JUNE 24 SHOWED A VERY SLIGHT CHANGE IN THE AREA OR INTENSITY OF DROUGHT ACROSS THE BLACKSBURG HSA. D3 OR EXTREME DROUGHT IS AFFECTING PORTIONS OF THE UPPER YADKIN RIVER BASIN IN ASHE...WILKES AND YADKIN COUNTIES. SEVERE DROUGHT (D2) WAS EDGED NORTHWARD AND NOW COVERS ALL THE REMAINING NORTH CAROLINA COUNTIES AND INTO EXTREME SOUTHERN VIRGINIA. MODERATE DROUGHT (D1) REMAINS OVER MOST OF THE NEW AND ROANOKE RIVER VALLEYS IN VIRGINIA. D0 OR ABNORMALLY DRY CONDITIONS...PERSIST OVER PARTS OF FAR WESTERN VIRGINIA AND INTO WEST VIRGINIA...EXCEPT FOR GREENBRIER COUNTY. IT SHOULD BE POINTED OUT THAT THE CATEGORIES ON THE DROUGHT MONITOR ARE GENERALIZED AND THE LOCAL IMPACTS OF DROUGHT MAY BE MORE OR LESS THAN WHAT IS DEPICTED ON THE MAP. THE CATEGORIES OF DROUGHT ARE EXPLAINED BELOW: D0 IS THE LEAST INTENSE INDICATOR OF DROUGHT ON A SCALE THAT RANGES FROM D0 THROUGH D4. IT IS BASICALLY A DROUGHT WATCH THAT INDICATES A REGION GOING INTO OR COMING OUT OF DROUGHT. D1 IS MODERATE DROUGHT...CONDITIONS THAT MAY BE ASSOCIATED WITH D1 INCLUDE SOME CROP DAMAGE...INCREASED FIRE RISK...FALLING RIVER... STREAM...AND RESERVOIR LEVELS AND SOME WATER SHORTAGES. D2 IS SEVERE DROUGHT...CROP OR PASTURE DAMAGE IS LIKELY. FIRE RISK IS POTENTIALLY HIGH...ALONG WITH WATER SHORTAGES AND POSSIBLE WATER RESTRICTIONS. D3 IS EXTREME DROUGHT...MAJOR CROP AND PASTURE LOSSES AND WIDESPREAD WATER SHORTAGES AND RESTRICTIONS. D4 IS EXCEPTIONAL DROUGHT...WIDESPREAD CROP AND PASTURE LOSSES... WATER SHORTAGES AND WATER EMERGENCIES. MAY BE THOUGHT OF AS THE 50-YEAR DROUGHT OR THE 2 PERCENT ANNUAL CHANCE OF OCCURRENCE. THE CATEGORIES ARE BASED ON A NUMBER OF KEY INDICATORS: 1) PALMER DROUGHT INDEX (PDSI) 2) CPC SOIL MOISTURE MODEL 3) USGS WEEKLY STREAMFLOW PERCENTILES 4) THE STANDARDIZED PRECIPITATION INDEX AND 5) THE SATELLITE VEGETATION INDEX. PALMER DROUGHT SEVERITY INDEX (PDSI)... THE TABLE BELOW SHOWS THE JUNE 21 2008 PDSI FOR THE SIX CLIMATE ZONES WHICH COVER THE BLACKSBURG HSA. THE INDEX FOR THE NORTH CAROLINA MOUNTAINS CONTINUED TO DECLINE IN THE PAST TWO WEEKS AND REMAINS WELL INTO THE EXTREME DROUGHT CATEGORY. THAT AREA NEEDS OVER A FOOT OF RAIN TO REACH NON-DROUGHT CONDITIONS. DROUGHT INDICES ALSO DECLINED IN ALL THE OTHER CLIMATE ZONES IN THE HSA AND SEVERE DROUGHT HAS BEEN REACHED IN THE SOUTHWEST VIRGINIA MOUNTAINS AND NORTHERN PIEDMONT OF NORTH CAROLINA. STATE CLIMATE ZONE PDSI PRECIP NEEDED TO BRING PDSI TO -0.5 NC N. MOUNTAINS -4.47 13.00 NC N. PIEDMONT -3.11 8.51 VA W. PIEDMONT -2.31 6.32 VA CENT. MTNS. -0.94 2.10 VA SW MOUNTAINS -3.31 7.59 WV SOUTHERN -1.21 2.44 THE PALMER INDEX IS CALCULATED WEEKLY AND INDICATES THE RELATIVE DRYNESS OR WETNESS AFFECTING AN AREA. THERE ARE SEVEN PDSI CATEGORIES DEFINING WET AND DRY CONDITIONS AS SHOWN IN THE TABLE BELOW: -4.0 OR LESS - EXTREME DROUGHT -3.0 TO -3.9 - SEVERE DROUGHT -2.0 TO -2.9 - MODERATE DROUGHT -1.9 TO +1.9 - NEAR NORMAL +2.0 TO +2.9 - UNUSUAL MOIST SPELL +3.0 TO +3.9 - VERY MOIST SPELL +4.0 OR ABOVE - EXTREMELY MOIST SOIL MOISTURE... THE NWS CLIMATE PREDICTION CENTER SOIL MOISTURE MODEL IS USED TO ESTIMATE SOIL MOISTURE IN THE TOP 4 TO 5 FEET USING RECENT OBSERVED DATA VERSUS LONG-TERM NORMALS. SLIGHT DEFICITS HAVE DEVELOPED OVER SOUTHEAST WEST VIRGINIA AND WESTERN VIRGINIA WHILE NORTHWEST NORTH CAROLINA NOW SHOWS DEFICITS OF 2 TO 4 INCHES. RIVERS AND STREAMFLOW... THE TABLE BELOW SHOWS 7-DAY AVERAGE STREAMFLOW PERCENTILE CLASSES FROM RIVER BASINS IN THE UNITED STATES GEOLOGICAL SURVEY (USGS) NETWORK. THE TABLE SHOWS THAT SEVERE HYDROLOGIC DROUGHT EXISTS IN MOST OF THE NEW RIVER BASIN IN NORTH CAROLINA AND VIRGINIA...IN THE YADKIN-PEE DEE IN NORTH CAROLINA AND IN THE UPPER ROANOKE AND TENNESSEE BASINS IN VIRGINIA. MODERATE HYDROLOGIC DROUGHT IS FOUND IN THE LOWER DAN AND ROANOKE RIVER BASINS. A NUMBER OF GAGES HAVE HAD NEW RECORD LOW FLOWS FOR THE DATE IN RECENT WEEKS ESPECIALLY IN THE YADKIN-PEE DEE RIVER BASIN IN NORTH CAROLINA AND IN THE UPPER ROANOKE IN VIRGINIA. RIVER BASIN PERCENTILE HYDROLOGIC DROUGHT CLASS CATEGORY NEW (VA/NC) <5 SEVERE UPPER ROANOKE <5 SEVERE UPPER DAN 10-24 BELOW NORMAL LOWER DAN-ROANOKE 6-9 MODERATE YADKIN-PEE DEE <5 SEVERE MIDDLE JAMES 10-24 BELOW NORMAL UPPER TENNESSEE <5 SEVERE RESERVOIR LEVELS... REDUCED INFLOWS HAVE BEGIN TO REDUCE LAKE LEVELS AT SEVERAL OF THE MAJOR RESERVOIRS IN THE HSA WITH THE EXCEPTION OF BLUESTONE AND CLAYTOR LAKES WHICH REMAIN LEVEL. BOTH LAKE MOOMAW AND W. KERR SCOTT HAVE FALLEN NEARLY TWO FEET IN THE PAST TWO WEEKS. RESERVOIR CURRENT POOL NORMAL POOL SMITH MOUNTAIN LAKE VA 792.60 795 CLAYTOR LAKE VA 1843.08 1846 LAKE MOOMAW VA 1579.34 1582 PHILPOTT RESERVOIR 971.76 974 BLUESTONE LAKE WV 1411.01 1410 W. KERR SCOTT NC 1027.96 1030 CARVINS COVE RESERVOIR...A MAJOR SOURCE FOR ROANOKE DRINKING WATER...IS 5.6 FEET BELOW THE SPILLWAY AND REMAINED FAIRLY STABLE IN RECENT WEEKS. SPRING HOLLOW RESERVOIR...WHICH SERVES ROANOKE COUNTY...IS 11.4 FEET BELOW ITS SPILLWAY. CLIMATE SUMMARY... HIGHLY VARIABLE IS THE BEST WAY TO DESCRIBE JUNE RAINFALL SO FAR. NUMEROUS CONVECTIVE EVENTS HAVE AFFECTED THE AREA WITH SEVERE STORMS AND SOME HEAVY RAINFALL BUT IT HAS BEEN A HIT AND MISS SITUATION. ROANOKE AIRPORT FOR EXAMPLE IS ABOVE NORMAL FOR THE MONTH WITH 3.50 INCHES TO DATE...WHILE BLACKSBURG...LYNCHBURG AND DANVILLE ARE ALL UNDER 50 PERCENT OF NORMAL JUNE RAINFALL. DANVILLE IN FACT HAS SEEN ONLY 0.81 INCHES AND IS ON A PACE FOR ITS DRIEST JUNE ON RECORD WHICH WAS 1.13 INCHES IN 1985. THE MONTH HAS ALSO BEEN VERY WARM...RUNNING 3 TO 5 DEGREES ABOVE NORMAL WHICH HAS INCREASED EVAPORATION LOSSES. THE TABLE BELOW SHOWS THAT MAY HAD ONLY 71 PERCENT OF NORMAL RAINFALL AT THE 77 NWS COOPERATIVE STATIONS...BUT SOME NORTH CAROLINA MOUNTAIN SITES HAD ONLY 25 TO 50 PERCENT. MONTH OR SEASON PRECIPITATION NORMAL % OF NORMAL MAY 3.15 4.42 71 SPRING 2008 (MAR-MAY) 11.55 12.28 94 APRIL 2008 4.95 3.72 133 MARCH 2008 3.42 4.14 83 WINTER 07-08 (DEC-FEB) 7.19 9.99 72 FALL 2007 (SEP-NOV) 8.49 10.51 81 SUMMER 2007 (JUN-AUG) 9.42 11.79 80 PRECIPITATION/TEMPERATURE OUTLOOKS... THE FIVE-DAY PRECIPITATION FORECAST FROM THE HYDROMETEOROLOGICAL PREDICTION CENTER (HPC) DOES NOT SHOW MUCH RAINFALL ACROSS THE REGION. THE VIRGINIA PIEDMONT IS FORECAST TO RECEIVE LESS THAN 0.50 INCHES WHILE MOUNTAIN AREAS ARE FORECAST TO RECEIVE UP TO 1.50 INCHES. IN ALL LIKELIHOOD THE RAINFALL WILL CONTINUE TO BE SPOTTY WITH POCKETS OF HEAVY RAINFALL BUT MANY AREAS RECEIVING LITTLE IF ANY. WITH A MEAN LONG-WAVE TROUGH EXPECTED TO DEVELOP AND PERSIST OVER THE EASTERN ONE-THIRD OF THE CONUS THE NWS CLIMATE PREDICTION CENTER IS FORECASTING NEAR NORMAL TEMPERATURES AND RAINFALL DURING THE 6 TO 10 DAY OUTLOOK PERIOD FROM JULY 1-5. IN THE 8 TO 14 DAY OUTLOOK THROUGH JULY 9 THE HIGHEST PROBABILITY IS FOR ABOVE NORMAL PRECIPITATION AND NEAR NORMAL TEMPERATURES. NEXT ISSUANCE DATE... THE NEXT DROUGHT STATEMENT WILL BE ISSUED ON OR ABOUT JULY 10 UNLESS CHANGED CONDITIONS WARRANT AN EARLIER UPDATE. RELATED WEBSITES... ADDITIONAL INFORMATION ON CURRENT AND FORECAST DROUGHT CONDITIONS MAY BE FOUND AT THE FOLLOWING WEB ADDRESSES /USE LOWER CASE LETTERS:/ U.S. DROUGHT MONITOR...HTTP://WWW.DROUGHT.UNL.EDU/DM NATIONAL INTEGRATED DROUGHT INFORMATION SYSTEM... HTTP://WWW.DROUGHT.GOV NWS CLIMATE PREDICTION CENTER...HTTP://WWW.CPC.NCEP.NOAA.GOV UNITED STATES GEOLOGICAL SURVEY... HTTP://WATERDATA.USGS.GOV/WATERWATCH NORTH CAROLINA DROUGHT MANAGEMENT ADVISORY COUNCIL... HTTP://WWW.NCDROUGHT.ORG/ VIRGINIA DEPARTMENT OF ENVIRONMENTAL QUALITY... HTTP://WWW.DEQ.VIRGINIA.GOV/ ACKNOWLEDGMENTS... THE DROUGHT MONITOR IS A MULTI-AGENCY EFFORT INVOLVING THE NATIONAL WEATHER SERVICE...NATIONAL CLIMATIC DATA CENTER...USDA ...STATE AND REGIONAL CLIMATOLOGISTS AND DROUGHT MITIGATION CENTER. INFORMATION FOR THIS STATEMENT HAS BEEN GATHERED FROM NWS...STATE COOPERATIVE EXTENSION SERVICES ...THE USDA...USACE AND USGS. QUESTIONS OR COMMENTS... PLEASE CONTACT... NATIONAL WEATHER SERVICE 1750 FORECAST DR. BLACKSBURG VA 24060 PHONE: 540-552-1341 $$ PC