000 WWUS84 KOHX 240758 SPSOHX SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE NASHVILLE TN 258 AM CDT FRI AUG 24 2007 TNZ005>011-022>034-056>066-075-077>080-093>095-241700- BEDFORD-BENTON-CANNON-CHEATHAM-CLAY-COFFEE-CUMBERLAND-DAVIDSON- DEKALB-DICKSON-FENTRESS-GILES-GRUNDY-HICKMAN-HOUSTON-HUMPHREYS- JACKSON-LAWRENCE-LEWIS-MACON-MARSHALL-MAURY-MONTGOMERY-OVERTON-PERRY- PICKETT-PUTNAM-ROBERTSON-RUTHERFORD-SMITH-STEWART-SUMNER-TROUSDALE- VAN BUREN-WARREN-WAYNE-WHITE-WILLIAMSON-WILSON- 258 AM CDT FRI AUG 24 2007 ...HEAT ADVISORY UNTIL 7 PM TODAY FOR MIDDLE TENNESSEE EXCEPT PLATEAU... YESTERDAYS HIGH TEMPERATURE OF 103 DEGREES SET ANOTHER DAILY HIGH RECORD IN NASHVILLE. THE PREVIOUS RECORD WAS 100 DEGREES BACK IN 1983. NASHVILLE ALSO BROKE THE RECORD FOR THE HIGHEST DAILY MINIMUM TEMPERATURE FOR AUGUST 23RD WITH 78 DEGREES. THE PREVIOUS RECORD WAS 75 DEGREES IN 1989. CROSSVILLE BROKE THE RECORD HIGH FOR AUGUST 23RD WITH 98 DEGREES. THE PREVIOUS RECORD WAS 96 SET IN 1968. CLARKSVILLE HIT 103 DEGREES YESTERDAY AFTERNOON. NASHVILLE WILL LIKELY BREAK ANOTHER RECORD TODAY WITH A FORECAST HIGH OF 102 DEGREES. THE RECORD HIGH FOR AUGUST 24TH IS 100 DEGREES SET BACK IN 1943. THE RECORD HIGH FOR AUGUST 24TH AT THE CLARKSVILLE SEWAGE PLANT IS 104 DEGREES...COLUMBIA 99 DEGREES...LEBANON 101 DEGREES... MCMINNVILLE 98 DEGREES...MURFREESBORO 101 DEGREES. NEW RECORDS COULD BE SET AGAIN TODAY IN A FEW AREAS. NASHVILLE HAS BROKEN FOUR DAILY HIGH TEMPERATURE RECORDS THIS MONTH...AND EITHER BROKEN OR TIED...SEVEN...HIGHEST DAILY MINIMUM TEMPERATURE RECORDS. YESTERDAY MARKED THE 14TH DAY OF 100 DEGREES OR ABOVE IN NASHVILLE THIS MONTH...THIS SUMMER AND THIS YEAR SO FAR. THIS IS TWICE AS MANY DAYS AS PREVIOUSLY RECORDED IN THE MONTH OF AUGUST. THE PREVIOUS RECORD WAS 7 DAYS SET BACK IN 1954. IT IS ALSO THE MOST EVER RECORDED IN ANY MONTH. THE PREVIOUS RECORD WAS 11 DAYS BACK IN JUNE 1952. AS FOR THE SUMMER...BACK IN 1954...NASHVILLE HAD 20 DAYS OF TRIPLE DIGIT TEMPERATURES...AND IN 1952...WE HAD 19. CURRENTLY...AUGUST 2007 IN NASHVILLE IS AVERAGING 9.4 DEGREES ABOVE NORMAL. THIS IS NEARLY 5 DEGREES HOTTER THAN THE HOTTEST AUGUST ON RECORD...WHICH WAS IN 1995. AUGUST 2007 COULD ALSO END UP BEING THE HOTTEST...OF ANY MONTH SINCE RECORD KEEPING BEGAN IN NASHVILLE... NEARLY 137 YEARS AGO. THE DAILY HIGH TEMPERATURE IN NASHVILLE THIS MONTH IS AVERAGING 100 DEGREES THROUGH AUGUST 23RD. NORMAL HIGH IS 87 DEGREES. THERE HAVE BEEN 22 CONSECUTIVE DAYS OF 95 DEGREES AND ABOVE IN NASHVILLE. THIS IS UNPRECEDENTED IN THE WEATHER RECORDS AT NASHVILLE. THE OLD RECORD WAS 19 DAYS BACK IN JUNE 1952. THIS STREAK WILL LIKELY CONTINUE FOR THE NEXT FIVE OR SIX DAYS. YESTERDAY WAS THE 29TH CONSECUTIVE DAY OF 90 DEGREES AND ABOVE IN NASHVILLE. A STRING THAT BEGAN BACK ON JULY 26TH. THIS IS THE MOST SINCE JUNE 1954...AND THE 3RD MOST ON RECORD. THE MOST EVER RECORDED IS 31 DAYS BACK IN JUNE OF 1952 AND AGAIN IN JUNE OF 1954. WE SHOULD BREAK THIS STRING. THE 106 DEGREES ON AUGUST 16TH NOT ONLY BROKE THE RECORD HIGH TEMPERATURE FOR THAT DATE...BUT ALSO BROKE THE ALL TIME RECORD HIGH FOR THE MONTH OF AUGUST...WHICH HAD BEEN 105 DEGREES SET BACK IN AUGUST 1930. THIS ALSO WAS THE HOTTEST TEMPERATURE IN NASHVILLE IN THE LAST 55 YEARS...ONLY SURPASSED BY THE ALL TIME RECORD HEAT OF 107 DEGREES BACK ON JULY 27TH AND 28TH 1952. WE HAVE HAD 29 DAYS WITH ONLY 0.05 INCHES OF RAIN IN NASHVILLE. BACK IN 1925...NASHVILLE WENT 31 DAYS WITH ONLY 0.05 INCHES OF RAIN. THAT STRETCH STARTED ON MAY 18TH AND ENDED ON JUNE 17TH. THE DRIEST AUGUST ON RECORD...WAS BACK IN 1929 WHEN ONLY 0.51 INCHES FELL. OTHER DRY AUGUSTS INCLUDE...1936...1968 AND 1987. SINCE THE FIRST OF JUNE...NASHVILLE HAS RECORDED ONLY 3.89 INCHES OF RAINFALL. THE DRIEST JUNE THROUGH AUGUST ON RECORD...WAS IN 1954...WHEN 4.74 INCHES OF RAIN FELL. OTHER YEARS WITH A DRY JUNE THROUGH AUGUST INCLUDE...1925...1948 AND 1943. RAINFALL SINCE JANUARY 1ST HAS TOTALED 17.36 INCHES...WHICH IS 14.41 INCHES BELOW NORMAL. COMPUTER MODELS RETROGRADE THE STRONG UPPER LEVEL HIGH PRESSURE SYSTEM THIS WEEKEND...ALLOWING A TROUGH TO DEVELOP OVER THE GREAT LAKES REGION. THIS TROUGH WILL ALLOW FOR A WEAK COOL FRONT TO GET CLOSE ENOUGH ON SATURDAY TO BRING AT LEAST A CHANCE FOR ISOLATED THUNDERSTORMS...MAINLY NORTH OF INTERSTATE 40 ON SATURDAY...AND SATURDAY NIGHT. THE TROUGH WILL BE SHORT LIVED...AS THE STRONG UPPER LEVEL RIDGE BUILDS BACK INTO OUR REGION...ON SUNDAY. UNFORTUNATELY... THERE IS NO SIGNIFICANT RAIN IN SIGHT FOR MIDDLE TENNESSEE...THROUGH NEXT WEEK. WE ARE CURRENTLY CLASSIFIED AS HAVING AN EXTREME TO EXCEPTIONAL DROUGHT CONDITIONS ACROSS MIDDLE TENNESSEE. DROUGHTS AND HEAT WAVES ARE PART OF THE NATURAL VARIABILITY OF OUR WEATHER AND CLIMATE. IN OUR REGION...SUMMER DROUGHTS AND HEAT WAVES ARE A RESULT OF A STRONG UPPER LEVEL HIGH PRESSURE SYSTEM THAT EXTENDS TO GREAT HEIGHTS IN THE ATMOSPHERE...AND REMAINS ENTRENCHED OVER OUR REGION FOR SEVERAL WEEKS. THIS WAS THE CASE IN THE 1930S... EARLY TO MID 1950S...1980...1983...AND THE MID TO LATE 1980S...AND NOW IN 2007. ONCE THIS PATTERN BECOMES ESTABLISHED IT OFTEN PERSIST THE WHOLE SEASON. A RING OF FIRE OFTEN DEVELOPS ON THE PERIPHERY OF THE UPPER LEVEL HIGH PRESSURE SYSTEM. ONCE A DROUGHT GETS UNDERWAY... IT HAS AN INSIDIOUS WAY OF FEEDING UPON ITSELF. MOISTURE THAT IS NORMALLY IN THE SOIL TENDS TO COOL THE LOWER PART OF THE ATMOSPHERE...THROUGH EVAPORATION OF WATER. AS THE SOIL DRIES...THIS PROCESS BECOMES WEAKER. DESSICATED SOIL RERADIATES THE INCOMING SUNLIGHT INTO THE LOWER ATMOSPHERE...INTENSIFYING THE HEAT AND LEADING TO EVEN DRIER CONDITIONS. DURING THE HEAT WAVE...SOME PRECAUTIONS SHOULD BE KEPT IN MIND. STAY INSIDE TO THE EXTENT POSSIBLE...PREFERABLY IN AN AIR CONDITIONED SPACE. IF YOU MUST BE OUTSIDE...DRINK FLUIDS FREQUENTLY... WEAR LIGHT COLORED CLOTHING WITH A HAT...AND STAY IN THE SHADE AS MUCH AS POSSIBLE. $$ BOBBY BOYD