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FGUS74 KMRX 021441
ESFMRX
DROUGHT INFORMATION STATEMENT
NATIONAL WEATHER SERVICE MORRISTOWN TN
1100 AM EDT FRI MAY 2 2008
...DROUGHT IMPROVES IN EAST TENNESSEE, EXTREME SOUTHWEST VIRGINIA, AND
CHEROKEE AND CLAY COUNTIES IN NORTH CAROLINA. PLEASE NOTE FORMAT CHANGE
FOR THIS ANNOUNCEMENT...
SYNOPSIS...
THIS STATEMENT IS ALSO ISSUED UNDER AWIPS HEADER MEMPNSMRX, AND WMO HEADER
NOUS44 KMRX.
ALL GEOGRAPHIC DESCRIPTIONS ARE APPROXIMATE.
D2 (SEVERE) DROUGHT CONDITIONS EXIST IN SOUTHEAST TENNESSEE GENERALLY SOUTH OF
A LINE FROM TELLICO PLAINS TO ROCKWOOD, AND OVER THE SOUTHERN CUMBERLAND
PLATEAU. THIS INCLUDES THE CHATTANOOGA METRO AREA. SUCH CONDITIONS ALSO EXIST
IN CHEROKEE AND CLAY COUNTIES, IN NORTH CAROLINA.
D1 (MODERATE) DROUGHT EXISTS GENERALLY SOUTH OF A LINE FROM DEER LODGE TO
KNOXVILLE (INCLUDING THE KNOXVILLE METRO AREA) TO DANDRIDGE TO KINGSPORT, IN
EAST TENNESSEE. THIS INCLUDES THE GREAT SMOKY MOUNTAINS, AND MOST OF THE
TRI-CITIES METRO AREA. IN VIRGINIA, THEY EXIST OVER THE SOUTHERN HALF OF
WASHINGTON COUNTY. IT ALSO INCLUDES THE CITY OF BRISTOL.
D0 (ABNORMALLY DRY) CONDITIONS EXIST IN EAST TENNESSEE NORTH OF A LINE FROM
DEER LODGE TO KNOXVILLE (EXCLUDING THE KNOXVILLE METRO AREA) TO DANDRIDGE TO
KINGSPORT, AND IN VIRGINIA IN LEE, SCOTT, WISE, RUSSELL, AND THE NORTHERN THIRD
OF WASHINGTON COUNTIES.
A SMALL SLIVER OF SCOTT COUNTY, TN ALONG THE KENTUCKY BORDER IS IN A NEAR
NORMAL STATE OF WETNESS.
SUMMARY OF IMPACTS...
NO WIDESPREAD LOCAL OR STATE WATER SUPPLY, FIRE, NAVIGATION, OR RECREATIONAL
IMPACTS ARE KNOWN. SOME SMALL SPRINGS AND WELLS ARE STILL LOWER THAN NORMAL
AROUND THE REGION, WHICH AFFECT LOCAL OR INDIVIDUAL WATER SUPPLIES. FOR
INFORMATION ON LOCAL WATER RESTRICTIONS, PLEASE CALL YOUR LOCAL WATER BOARD.
NO WIDESPREAD FIRE RESTRICTIONS ARE KNOWN TO EXIST, HOWEVER CONTACT LOCAL
AUTHORITIES FOR FURTHER INFORMATION OR PERMITS.
CLIMATE SUMMARY...
RAINFALL AT INDIVIDUAL POINTS IS NOT ALWAYS AN ACCURATE REFLECTION OF AN
AREA'S PRECIPITATION. RAINFALL OVER LARGE AREAS IS A MORE REALISTIC
REPRESENTATION A REGION'S RAIN SITUATION. BELOW ARE THE DATA FOR THE MAIN
NATIONAL WEATHER SERVICE OBSERVATION POINTS FOR THE PERIOD STARTING
JANUARY 1, 2007. THE DATA GO THROUGH MIDNIGHT THURSDAY, MAY 1, 2008:
SITE RAIN NORM DEFICIT %NORM
CHATTANOOGA 56.00 75.32 -19.32 74
KNOXVILLE 49.90 66.10 -16.20 75
OAK RIDGE 54.23 74.87 -20.64 75
TRI-CITIES 36.19 55.51 -19.32 65
NWS MORRISTOWN 44.59 62.00 -17.41 72
RAIN TOTAL OVER LARGE AREAS SUCH AS RESERVOIR DRAINAGE BASINS IS A MUCH
BETTER INDICATOR OF AN AREA'S "RAIN HEALTH" THAN SIMPLE POINT TOTALS. BELOW
ARE THE DATA FOR THE TVA BASINS IN THE UPPER TENNESSEE RIVER DRAINAGE FOR THE
PERIOD STARTING JANUARY 1, 2007. THE DATA GO THROUGH 6 AM THURSDAY, MAY 1, 2008:
BASIN RAIN NORM DEFICIT %NORM
SOUTH HOLSTON 44.69 58.53 -13.84 76
WATAUGA 45.54 61.92 -16.38 74
BOONE 41.96 60.12 -18.16 70
CHEROKEE 43.32 59.01 -15.69 73
DOUGLAS 45.56 62.74 -17.18 73
FONTANA 58.81 80.17 -21.36 73
NORRIS 45.65 61.76 -16.11 74
MELTON HILL 50.54 66.82 -16.28 76
CHATUGE 49.86 80.32 -30.46 62
NOTTELY 56.68 74.57 -17.89 76
HIWASSEE 52.28 78.05 -25.77 67
FT. LOUDOUN/TELLICO 45.16 65.87 -20.71 69
WATTS BAR 51.80 69.58 -17.78 74
CHICKAMAUGA 44.23 72.98 -28.75 61
NICKAJACK 43.43 73.96 -30.53 59
GUNTERSVILLE 41.83 75.18 -33.35 56
TEMPERATURES IN THE REGION WERE NEAR NORMAL DURING THE MONTH OF APRIL. TWO COLD
SNAPS IN THE MIDDLE AND END OF THE MONTH BROUGHT MUCH ABOVE NORMAL TEMPERATURES DOWN TO EARTH. CHATTANOOGA ENDED THE MONTH ABOUT 1.6 DEGREES ABOVE NORMAL. KNOXVILLE WAS 1.7 DEGREES ABOVE NORMAL FOR THE MONTH. OAK RIDGE WAS NEARLY BALMY WITH 2.5 DEGREES ABOVE NORMAL FOR THE MONTH. TRI-CITIES AIRPORT WAS 1.6 DEGREES ABOVE NORMAL. AGAIN, A COLD SNAP AT MONTHS END BROUGHT THE AVERAGE DOWN FROM VERY MUCH WARMER THAN NORMAL FOR MOST OF THE MONTH.
WARMER THAN AVERAGE TEMPERATURES MEAN MORE EVAPORATION FROM TOP SOILS AND DRIER
SOIL CONDITIONS. HOWEVER, THIS CAN BE BALANCED OUT BY RAIN FALLING AT KEY TIMES
AND OVER LONGER PERIODS. THE FACT THAT TWO MAJOR COLD SPELLS OCCURRED DURING
THE MONTH MEANS THAT MUCH LESS EVAPORATION THAN NORMAL OCCURRED DURING THOSE
TIMES. OVERALL, A FAIRLY AVERAGE MONTH FOR TEMPERATURES.
PRECIPITATION/TEMPERATURE OUTLOOK...
THROUGH ABOUT MAY 11, GENERAL CONDITIONS ARE EXPECTED TO BE ABOUT NORMAL FOR
TEMPERATURE, WITH ABOVE AVERAGE RAINFALL FOR THE REGION AS A WHOLE. INDIVIDUAL
LOCATIONS MAY VARY.
THE SECOND WEEK OF MAY IS EXPECTED TO BE COOLER AND WETTER THAN NORMAL.
THE PERIOD OF MAY THROUGH JULY IS EXPECTED TO ABOUT NORMAL FOR BOTH TEMPERATURE
AND RAINFALL.
THE RAMIFICATIONS OF THIS OUTLOOK ARE THAT LOWER THAN NORMAL EVAPOTRANSPIRATION
COULD OCCUR. LESS EVAPOTRANSPIRATION MEANS THAT TOP SOILS COULD REMAIN SLIGHTLY
WETTER THAN NORMAL, AND STREAM FLOWS WOULD BENEFIT, TOO. FOR RESERVOIR LEVELS
TO RISE SIGNIFICANTLY, MUCH HIGHER THAN AVERAGE RAIN MUST OCCUR. THIS IS NOT
ANTICIPATED AT THIS TIME, THOUGH SOME IMPROVEMENT IS EXPECTED.
HYDROLOGIC SUMMARY AND OUTLOOK...
DURING THE LAST WEEK OF APRIL, STREAMS COMING OUT OF THE MOUNTAINS INTO EAST
TENNESSEE AND IN EXTREME SOUTHWEST VIRGINIA HAD BENEFITED GREATLY FROM RECENT
HEAVY RAINS. EXTREME SOUTHWEST NORTH CAROLINA STREAMS DID NOT BENEFIT AS MUCH.
STREAMFLOWS THAT WEEK WERE ABOVE THE 75TH PERCENTILE IN EAST TENNESSEE AND
EXTREME SOUTHWEST VIRGINIA, AND ABOVE NORMAL IN CHEROKEE AND CLAY COUNTIES.
FLOODING WAS NOT A PROBLEM BUT THEY HAD NOT BEEN THAT HIGH FOR MONTHS.
THIS HAS CHANGED AND FLOWS ARE NOW DROPPING BACK TO NORMAL AND EVEN LOWER
LEVELS. THIS INDICATES THAT GROUND WATER TABLES ARE STILL BELOW NORMAL.
RAINFALL HITTING THE GROUND DURING A DROUGHT ENTERS THE WATER TABLE INSTEAD OF
RUNNING OFF INTO CHANNELS. HENCE, RESERVOIRS FILL MORE SLOWLY THAN THEY
OTHERWISE WOULD. WHILE TOP SOILS ARE WETTER THAN THEY HAVE BEEN IN WEEKS,
GROUND WATER IS STILL LOW.
THE OUTLOOK FOR LARGE TRIBUTARIES OF THE TENNESSEE RIVER THROUGH EARLY SUMMER
IS FOR A LESS THAN NORMAL CHANCE OF FLOODING. THIS WILL DEPEND LARGELY ON THE
AMOUNT OF RAIN OVER THE LONG TERM AND THE NUMBER OF HEAVY RAIN EVENTS IN THE
PERIOD. BUT IT WILL ALSO DEPEND ON THE HYDROGRAPHY OF THE INDIVIDUAL STREAM.
THINGS LIKE LOCAL GEOGRAPHY, WHETHER SINKHOLES ACCOUNT FOR MUCH UNDERGROUND
STORAGE, LOCAL LAND USE, FLORA, AND SO FORTH, WILL ALSO MAKE A DIFFERENCE.
FOR SMALL STREAMS AND URBAN AREAS, THIS WILL DEPEND ENTIRELY ON THE AMOUNT OF
RAIN RECEIVED IN A SHORT TIME, AND CHARACTERISTICS OF THE SPOT IN WHICH IT
FALLS, SUCH AS PAVEMENT OR CONCRETE, TOPOGRAPHY, ETC.
NEXT ISSUANCE DATE...
THE NEXT DROUGHT INFORMATION STATEMENT WILL BE ISSUED ON OR BEFORE MAY 23, 2008,
DEPENDING ON THE SITUATION. IF NO LARGE SCALE CHANGES OCCUR IN THE DROUGHT
SITUATION, IT WILL BE LATER THAN SOONER. WE WILL MONITOR THE SITUATION
AND KEEP YOU ABREAST.
RELATED WEB SITES...
FOR ONE-STOP SHOPPING ON THE DROUGHT IN THE REGION GO TO
HTTP://WWW.SRH.NOAA.GOV/MRX/HYDRO/DROUGHT07/MAIN.PHP
OR YOU CAN GO TO WWW.WEATHER.GOV THEN CLICK ON THE EAST TENNESSEE REGION, AND
THEN CLICK ON THE DROUGHT INFORMATION LINK AT THE BOTTOM OF THE
MORRISTOWN, TENNESSEE HOME PAGE.
YOU MAY ALSO VISIT WWW.TVA.GOV FOR MORE INFORMATION ON LAKES LEVELS,
STREAMFLOWS AND RAINFALL IN THE TENNESSEE VALLEY AUTHORITY SYSTEM.
STREAMFLOW DATA CAN ALSO BE OBTAINED FROM THE UNITED STATES GEOLOGICAL SURVEY
AT HTTP://WATERDATA.USGS.GOV/NWIS/RT AND THEN CLICKING ON YOUR STATE OF
INTEREST.
ADDITIONAL LONG TERM STREAMFLOW FORECASTS CAN BE OBTAINED AT THE NWS
MORRISTOWN "ADVANCED HYDROLOGIC PREDICTION SERVICES" WEBSITE AT
HTTP://AHPS.SRH.NOAA.GOV/INDEX.PHP?WFO=MRX
FOR SPECIFIC DATA, DROUGHT INDICES, AND THE NATIONAL DROUGHT PICTURE WITH
CLICKABLE ZOOMING, GO TO HTTP://WWW.DROUGHT.UNL.EDU/DM/
ACKNOWLEDGMENTS...
APPRECIATION FOR THE DATA IN THIS DOCUMENT GO TO THE TENNESSEE VALLEY
AUTHORITY (TVA), UNITED STATES GEOLOGICAL SURVEY (USGS), THE STATES OF
TENNESSEE AND NORTH CAROLINA, THE COMMONWEALTH OF VIRGINIA, THE U.S. ARMY
CORPS OF ENGINEERS (USACE), THE NATIONAL PARK SERVICE (NPS), THE NATIONAL
FOREST SERVICE (NFS), THE UNIVERSITY OF NEBRASKA AT LINCOLN FOR HOSTING THE
DROUGHT MONITOR WEBSITE, AND NUMEROUS COUNTY AND CITY OFFICIALS. ALSO, THANKS
GO TO VARIOUS MEDIA OUTLETS INCLUDING TELEVISION AND RADIO STATIONS AND
NEWSPAPERS, FOR ASKING THE QUESTIONS THE DRIVE THE GATHERING OF DATA AND
IMPACT INFORMATION.
QUESTIONS OR COMMENTS...
FOR MORE INFORMATION OR FOR MEDIA INTERVIEWS PLEASE CONTACT:
BRIAN BOYD
SENIOR SERVICE HYDROLOGIST
NATIONAL WEATHER SERVICE
5974 COMMERCE BLVD.
MORRISTOWN, TN 37814
423-586-1964 (MEDIA ONLY; FOR IMMEDIATE RESPONSE)
423-586-2296 (ALL OTHER CALLS; MAY GET VOICE MAIL)
423-586-6429 (FOR IMMEDIATE RESPONSE, NON-MEDIA CALLS, IF 2296 IS NOT AVAILABLE)
EMAIL: BRIAN.BOYD@NOAA.GOV
WEBSITE: WWW.SRH.NOAA.GOV/MRX
NOTE: IN THE EVENT THE ABOVE PERSON IS NOT AVAILABLE, OTHER STAFF MEMBERS WILL
BE ABLE TO HELP YOU.
www.weather.gov 
National Weather Service Forecast Office
