Flash Flood Warning 1, NWS Jackson, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
427 AM EST THU DEC 13 2007

.SHORT TERM.../TODAY THROUGH SATURDAY/...UPDATED

BEST AGREEMENT AMONGST THE VARIOUS MODELS OVERNIGHT WAS BETWEEN THE
UKMET...ECMWF...AND GFS SOLUTIONS. THE NAM WAS AN EXTREME
OUTLIER...ESPECIALLY WITH REGARD TO SATURDAYS WEATHER SYSTEM AND
PRECIPITATION PATTERN. THAT BEING SAID THE GFS WAS THE MODEL OF
CHOICE BASED ON THE SUPPORT IT HAD FROM THE UKMET...NGM...AND ECMWF
RUNS. FORECAST FOR TODAY WAS IN GOOD SHAPE ALREADY AND ONLY A FEW
VERY MINOR TWEAKS WERE MADE. A SHOT OF MODERATE TO HEAVY RAINFALL IS
STILL EXPECTED LATER THIS MORNING...WITH THE POTENTIAL FOR SOME MINOR
FLOODING IN THE WESTERN HALF OF THE FORECAST AREA. A FLOOD WATCH IS
STILL IN EFFECT THROUGH 2 PM THIS AFTERNOON. TEMPERATURES FOR TODAY
WILL BE ABOVE NORMAL ONCE AGAIN. A FAST MOVING COLD FRONT WILL BRING
THE PRECIP TO EAST KENTUCKY TODAY. A POTENT AREA OF LOW PRESSURE WILL
THEN MOVE OUT OF THE SOUTHERN PLAINS FRIDAY NIGHT...BRINGING A CHANCE
OF RAIN AND SNOW SHOWERS TO THE AREA THROUGH SATURDAY EVENING. AS THE
LOW MOVES UP THE SPINE OF THE APPALACHIAN MOUNTAINS SATURDAY
NIGHT...THE PRECIPITATION WILL TRANSITION TO ALL SNOW AFTER
MIDNIGHT...WITH LIGHT ACCUMULATIONS POSSIBLE ALONG AND NORTH OF THE
HAL ROGERS PARKWAY AND HIGHWAY 80 CORRIDOR. SOME LIGHT SNOW SHOWERS
AND FLURRIES WILL LINGER INTO SUNDAY MORNING. WENT CLOSE TO METMOS
FOR TEMPERATURES ACROSS THE BOARD...WITH TWEAKS MADE TOWARD EXPECTED
TRENDS. SATURDAYS HIGH TEMPERATURE WILL OCCUR DURING THE
MIDMORNING...WITH FALLING TEMPERATURES THROUGHOUT THE DAY. MODEL
SOUNDINGS AND CROSS SECTIONS SHOWING PLENTY OF VERTICAL MOTION...LOW
AND MID LEVEL MOISTURE...MIDDLE AND UPPER LEVEL JET SUPPORT...AND
THE PROPER VERTICAL TEMPERATURE STRUCTURE TO SUPPORT SNOWFALL. THE
SPEED OF THE SYSTEM...COUPLED WITH THE TIMING OF THE COLD AIR BEHIND
IT AND WARM GROUND...WILL BE MAJOR FACTORS IN DETERMINING EXACTLY
HOW MUCH SNOW FALLS AND IS ABLE TO ACCUMULATE SATURDAY NIGHT. ZONES
ALREADY OUT.

.LONG TERM.../FRIDAY THROUGH WEDNESDAY/

THE WEEKEND WEATHER SYSTEM IS BECOMING MUCH CLEARER AS THE MODELS
CONVERGE ON A SOLUTION. CURRENTLY THE VARIATION HAS THE LOW TRACKING
UP INTESTATE 75 SAT/SAT NIGHT WITH THE GFS ABOUT 4 HRS FASTER THAN
THE ECMWF. ERN KY SHOULD STAY IN THE WARM SECTOR UNTIL AFTER THE LOW
TRACKS INTO OH. THEN THE COLD AIR WILL SINK INTO THE REGION AND
CHANGE THE REMAINING PCPN FROM RAIN TO A RAIN/SNOW MIX AND THEN ALL
SNOW BY SUN MORNING. HEAVIEST PCPN WILL OCCUR BEFORE THE LOW PASSES
WITH EXPECTED SNOW ACCUM SAT NITE/SUN OF AROUND AN INCH WITH NEARLY
AN INCH AND A HALF FOR THE MTNS AND PROBABLY LESS THAN AN INCH FOR
THE SRN COUNTIES CLOSER TO I-75. POSSIBILITY OF FLURRIES LINGERING
IN THE MTNS SUN NITE BUT TEMPS TO WARM THRU THE WEEK WITH DRY
WEATHER. NEXT SYSTEM CURRENTLY NOT PROGGED INTO AREA UNTIL THU AT THE
EARLIEST.

&&

.AVIATION.../06Z TO 06Z/

CONDITIONS REMAIN IFR OR WORSE ACROSS THE FORECAST AREA...EXCEPT FOR
A FEW LOCATIONS NEAR THE TN LINE WHICH ARE MVFR ATTM. A WARM FRONT
EXTENDS FROM EKQ TO SME TO SW PIKE COUNTY. CEILINGS ARE LOWEST ALONG
AND NORTH OF THE BOUNDARY...WITH VIS THE MOST RESTRICTED ON
RIDGETOPS. THE WARM FRONT WILL MOVE FURTHER NORTH INTO THE CWA
TONIGHT AND REACH AT LEAST AS FAR N AS THE MTN PARKWAY OVERNIGHT AS A
SFC WAVE APPROACHES OVERNIGHT...AND THEN SOUTHEAST INTO VA AS A COLD
FRONT 12Z AND AFTER AS THE WAVE MOVES BY. SHRA IS EXPECTED...WITH
HEAVIEST AND MOST RESTRICTED VIS FROM SHRA IN THE WESTERN HALF OF THE
CWA. SOME IMPROVEMENT IN CIGS THOUGH LIKELY ONLY ONE CAT MAY OCCUR
LATE TONIGHT AS PRECIP ARRIVES...BUT PROBABLY STILL NOT INTO MVFR AT
TAF SITES UNTIL 14 TO 16Z. AS PRECIP ENDS ON THU...VIS WILL IMPROVE...
BUT MVFR CEILINGS SHOULD PERSIST. LOW LEVEL WIND SHEAR WILL ALSO BE
A CONCERN FOR A TIME BETWEEN ABOUT 10Z AND 16Z AS LOW LEVEL JET
INCREASES AND IS MAXIMIZED OVER THE AREA. VFR OR PERHAPS MVFR IN BR
IS POSSIBLE AT THE END OF THE PERIOD AS DRIER AIR WORKS IN.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH UNTIL 2 PM EST THIS AFTERNOON FOR KYZ044-050>052-
058>060-068-069-079-080-083-084-104-106>109-111-112-114-116-119.

&&

SHORT TERM...AR
LONG TERM...
AVIATION...JP

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE JACKSON KY
454 AM EST THU DEC 13 2007

KYZ044-050>052-058>060-068-069-079-080-083-084-104-106>109-111-112-
114-116-119-141300-
FLEMING-MONTGOMERY-BATH-ROWAN-ESTILL-POWELL-MENIFEE-ROCKCASTLE-
JACKSON-PULASKI-LAUREL-WAYNE-MCCREARY-ELLIOTT-MORGAN-JOHNSON-WOLFE-
MAGOFFIN-LEE-BREATHITT-OWSLEY-CLAY-MARTIN-
454 AM EST THU DEC 13 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN KENTUCKY.

.DAY ONE...TODAY AND TONIGHT.

THERE IS A SLIGHT CHANCE OF THUNDERSTORMS EARLY THIS MORNING. LOCALLY
HEAVY RAINFALL WILL ALSO BE POSSIBLE THIS MORNING...POSSIBLY
RESULTING IN SOME MINOR FLOODING ISSUES. ANY THUNDERSTORM OR INTENSE
SHOWER WILL ALSO BE CAPABLE OF PRODUCING WIND GUSTS TO 40 MPH.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

SNOW SHOWERS WILL BE POSSIBLE FRIDAY NIGHT INTO SATURDAY AND AGAIN
SATURDAY NIGHT INTO SUNDAY MORNING. SOME LIGHT SNOW ACCUMULATIONS WILL
BE POSSIBLE SATURDAY NIGHT...ESPECIALLY ALONG RIDGETOPS.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO CALL IN REPORTS OF FLOODING...EXCESSIVE
RAINFALL AMOUNTS...AND SNOWFALL AMOUNTS TO THE NATIONAL WEATHER SERVICE
IN JACKSON.

KYZ085>088-110-113-115-117-118-120-141300-
WHITLEY-KNOX-BELL-HARLAN-FLOYD-KNOTT-PERRY-LESLIE-LETCHER-PIKE-
454 AM EST THU DEC 13 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EASTERN KENTUCKY.

.DAY ONE...TODAY AND TONIGHT.

THERE IS A SLIGHT CHANCE OF A THUNDERSTORM THROUGH LATE MORNING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY.

SNOW SHOWERS WILL BE POSSIBLE FRIDAY NIGHT INTO SATURDAY AND AGAIN
SATURDAY NIGHT INTO SUNDAY MORNING. SOME LIGHT SNOW ACCUMULATIONS WILL
BE POSSIBLE SATURDAY NIGHT...ESPECIALLY ALONG RIDGETOPS.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO CALL IN REPORTS OF FLOODING...EXCESSIVE
RAINFALL AMOUNTS...AND SNOWFALL AMOUNTS TO THE NATIONAL WEATHER SERVICE
IN JACKSON.

AR