Area Forecast Discussion
Issued by NWS Jackson, KY

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KJKL 262356
AFDJKL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE JACKSON KY
656 PM EST WED NOV 26 2014

.UPDATE...
ISSUED AT 655 PM EST WED NOV 26 2014

BASED ON THE LATEST SATELLITE DATA...WENT AHEAD AND INCREASED CLOUD
COVER ACROSS THE CWA...WITH CLOUDS EXPECTED TO CONTINUE THICKENING
THROUGHOUT THE EVENING AND OVERNIGHT. SOME OF THESE CLOUDS ARE
HIGH...BUT ARE COVERING A LARGE MAJORITY OF THE CWA...SO WENT AHEAD
AND INCLUDED BKN CLOUDS FOR THE REST OF THE EVENING.
CURRENTLY...TEMPERATURE READINGS ARE STILL IN THE UPPER 30S AND LOW
40S...WITH DEW POINT DEPRESSIONS 10 TO 20 DEGREES. ALTHOUGH WE ARE
GETTING A FEW RADAR RETURNS IN THE FAR SW PORTION OF THE CWA...IT IS
UNLIKELY THAT ANY OF THIS MOISTURE WILL MAKE IT TO THE SURFACE FOR AT
LEAST A FEW MORE HOURS. AND GIVEN THE CURRENT TEMPERATURES...ONCE
PRECIP DOES FALL...IT SHOULD BE IN THE FORM OF RAIN. LATEST FORECAST
SOUNDINGS FOR BOTH THE NAM AND GFS ARE STILL SHOWING TEMPERATURES
REMAINING ABOVE FREEZING THROUGH AT LEAST 6Z...IF NOT LONGER IN SOME
LOCATIONS...AND THEN HOVERING RIGHT AROUND THE FREEZING MARK
THEREAFTER UNTIL WARMING AGAIN AFTER DAY BREAK. HOWEVER...ACCORDING
TO THE LATEST WPC WINTER WEATHER ACCUMULATION FORECAST ISSUED AROUND
1630Z...2 TO 4 INCHES IS STILL EXPECTED IN THE SOUTHERN PORTION OF
THE CWA. IN OTHER WORDS...SOME GOOD WET BULBING PROCESSES ARE GOING
TO HAVE TO TAKE PLACE THIS EVENING IN ORDER FOR THIS TO PAN OUT. AS
SUCH...THERE HASN/T BEEN ENOUGH EVIDENCE TO CHANGE THE CURRENT
FORECAST SNOW TOTALS. STILL EXPECT WHAT DOES FALL TO MAINLY
ACCUMULATE ON THE GRASSY AND ELEVATED SURFACES...AND TURN INTO A
SLUSHY MIX OF RAIN AND SNOW ON THE ROADWAYS BEFORE QUICKLY MELTING
OFF.

WILL CONTINUE TO MONITOR TEMPS AND PRECIPITATION UPSTREAM AS THIS
SYSTEM NEARS AND BEGINS IMPACTING THE REGION...IN CASE ANY
MODIFICATIONS TO THE CURRENT SNOW/RAIN FORECAST NEED TO BE MADE.

&&

.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 315 PM EST WED NOV 26 2014

...SOME SLUSHY SNOW ACCUMULATIONS POSSIBLE LATE TONIGHT OVER SOUTHERN
PARTS OF EAST KENTUCKY...

19Z SFC ANALYSIS SHOWS EAST KENTUCKY IN BETWEEN TWO AREAS OF LOW
PRESSURE. TO THE EAST...A COASTAL LOW IS NOW PASSING NORTH OF CAPE
HATTERAS...WHILE A MORE MODERATE STRENGTH SFC LOW IS LOCATED OVER
CENTRAL MISSOURI ON ITS PATH SOUTHEAST INTO THE TENNESSEE VALLEY. IN
THE GAP BETWEEN THESE SYSTEMS ENOUGH CLEARING TOOK PLACE FOR MOST OF
THE AREA THAT TEMPERATURES CLIMBED INTO UPPER 40S AND LOWER 50S THIS
AFTERNOON. WINDS ARE GENERALLY LIGHT WHILE DEWPOINTS ARE FOUND IN THE
MID AND UPPER 20S...THOUGH WITH SOME 30S IN THE FAR EAST.

THE MODELS ARE IN PRETTY GOOD AGREEMENT...NOW THAT THE GFS IS
BREAKING TOWARD THE ECMWF AND NAM...ALOFT WITH THE CLIPPER SYSTEM
DROPPING INTO THE TENNESSEE VALLEY TONIGHT. THEY ALL SHOW THE
ENERGY...ASSOCIATED WITH EASTERN PORTION OF THE LARGE TROUGH IN
PLACE OVER THE OHIO VALLEY...LIFTING NORTHEAST INTO EASTERN NEW
ENGLAND BY THURSDAY MORNING. AT THE SAME TIME...A SECONDARY BATCH OF
ENERGY WITHIN THE LARGER TROUGH WILL RIDE SOUTHEAST FROM THE EAST
CENTRAL PLAINS TO THE TENNESSEE VALLEY...THOUGH SHEARING AS IT PASSES
BY KENTUCKY TO THE SOUTH TONIGHT. FOLLOWING THIS...THE WHOLE TROUGH
BODILY MOVES OUT OF THE REGION AND RISING HEIGHTS FOLLOW. HAVE
FOLLOWED A GENERAL MODEL BLEND FOR THE SHORT TERM PORTION THE
FORECAST WITH SOME CAUTIOUS FAVORING OF THE HIGHER RESOLUTION NAM12
AND HRRR FOR WX DETAILS.

SENSIBLE WEATHER WILL FEATURE A QUIET EVENING AS HIGH CLOUDS OVERTAKE
THE SKY AND LOWER WITH TIME. A WEAKENING AREA OF LOW PRESSURE WILL
SLIDE SOUTH THROUGH SOUTHERN KENTUCKY AND INTO EASTERN TENNESSEE.
THIS WILL BRING WITH IT A NARROW BAND OF PCPN CAPABLE OF BECOMING
SNOW GIVEN THE EXPECTED WETBULB EFFECT WHEN IT STARTS COMING DOWN
MODERATELY ACROSS OUR SOUTHERN COUNTIES. HOWEVER...SFC TEMPERATURES
WILL BE NEAR 32 DEGREES AT THEIR COLDEST LIKELY PREVENTING MUCH
ACCUMULATION ON ANYTHING MORE THAN GRASSY AND ELEVATED SURFACES AND
THEN MAINLY ON THE RIDGES AS THE VALLEYS REMAIN A MIX OF RAIN AND
SNOW. THIS IS A DISTURBINGLY SIMILAR SITUATION AS COMPARED TO LAST
NIGHT IN THE EAST WHERE THE HEAVIER PCPN STAYED JUST OFF TO THE EAST.
THESE SMALL SCALE DETAILS MAKE ALL THE DIFFERENCE IN MARGINAL
SITUATIONS AS THIS. HOWEVER...CANNOT RULE OUT A HEAVIER BURST OR TWO
OF SNOW THAT COULD CAUSE A SLUSHY ACCUMULATION ON THE ROADS. THIS
SHOULD NOT LAST LONG...THOUGH...AS ROAD TEMPERATURES ARE CURRENTLY IN
THE 40S AND 50S AND WILL ONLY SLOWLY FALL WITH THE PCPN TONIGHT. HAVE
ISSUED AN SPS TO DEAL WITH THE POTENTIAL FOR A SLUSHY INCH OF SNOW
THAT SHOULD HAVE A MINIMAL IMPACT ON TRAVELERS TONIGHT. THE LIGHT
SNOW/RAIN PULLS OUT OF THE AREA EARLY THURSDAY WITH COOLER
TEMPERATURES TO FOLLOW AS HIGH PRESSURE MOVES THROUGH THE SOUTHERN
APPALACHIANS INTO FRIDAY MORNING.

ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS
THROUGH THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE
SOME TERRAIN BASED ADJUSTMENTS TONIGHT INTO THURSDAY MAINLY TO LOWER
THE RIDGES IN OUR SOUTHERN COUNTIES DUE TO THE PCPN AND ANTICIPATED
WETBULBING. AS FOR POPS...ENDED UP CLOSE TO A BLEND OF THE DRIER MAV
AND WETTER MET NUMBERS TONIGHT INTO THURSDAY MORNING AND THEN
MATCHED THEIR DRY CONSENSUS INTO FRIDAY MORNING.

.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 245 PM EST WED NOV 26 2014

THE SYNOPTIC PATTERN THROUGH THE LONG TERM PERIOD WILL FEATURE A
PROGRESSIVE FLOW ALOFT WITH A GENERAL SOUTHWEST FLOW IN THE LOW
LEVELS AS AN ELONGATED AREA OF SURFACE HIGH PRESSURE STRETCHES OUT
FROM THE DEEP SOUTH EASTWARD INTO THE WESTERN ATLANTIC. A COLD FRONT
WILL DROP SOUTH INTO THE REGION ON MONDAY...AND THEN STALL OUT IN
OUR VICINITY AS THE SPONSORING UPPER TROUGH PASSES BY TO THE NORTH.
A SECOND TROUGH WILL THEN FOLLOW A SIMILAR TRACK AND PASS BY TO OUR
NORTH MIDWEEK. FORECAST MODELS DIFFER ON THE STRENGTH OF THIS
SHORTWAVE AND THE RESULTING IMPACT IT WILL HAVE ON THE FRONT
AND FORECASTER CONFIDENCE DROPS BELOW AVERAGE BY THE END OF THE
PERIOD.

OUR SENSIBLE WEATHER WILL FEATURE A MODERATING TREND OVER THE
THANKSGIVING HOLIDAY WEEKEND. UNFORTUNATELY...THE WARMING TEMPS WILL
BE ACCOMPANIED BY INCREASING CLOUDS AND A FEW SHOWERS BY SATURDAY
NIGHT INTO THE DAY ON SUNDAY AS LOW LEVEL MOISTURE INCREASES. RAIN
CHANCES THEN INCREASE DRAMATICALLY SUNDAY NIGHT INTO MONDAY AS THE
FRONT DROPS INTO THE AREA. BEYOND MONDAY...TEMPS AND RAIN CHANCES
ARE PROBLEMATIC DUE TO THE MODEL DIFFERENCES REGARDING THE PLACEMENT
OF THE FRONT. SIDING WITH A MODEL BLEND YIELDS NEAR NORMAL TEMPS AND
A CHANCE OF RAIN EACH PERIOD THROUGH WEDNESDAY.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 656 PM EST WED NOV 26 2014

VFR CONDITIONS WILL PREVAIL THROUGH THE AREA INTO THE EVENING BEFORE
THE CIGS START TO DROP...PARTICULARLY AT THE SOUTHERN SITES. EXPECT
AN AREA OF RAIN AND SNOW TO SLIDE THROUGH THE CUMBERLAND VALLEY
OVERNIGHT WITH A GOOD CHANCE OF DROPPING VIS AND CIGS INTO THE MVFR
AND IFR RANGES AS THE SNOW DEVELOPS AND PASSES THROUGH. THE SME AND
LOZ SITES WILL LIKELY SEE THE WORST CONDITIONS...THOUGH IF THE PCPN
IS NOT ABLE TO WET BULB TO SNOW EFFECTIVELY...AT LEAST THE VIS WILL
NOT BE AS LOW AS CURRENTLY FORECASTED. EXPECT THE CONDITIONS TO
GRADUALLY IMPROVE THROUGH THE DAY THURSDAY ONCE THIS WAVE PASSES...
BUT CIGS WILL PROBABLY BE MVFR AT MOST SITES THROUGH THE MORNING.
WINDS WILL BE LIGHT AND VARIABLE THROUGH THE NIGHT BEFORE PICKING UP
A BIT FROM THE NORTHWEST INTO THE MORNING IN THE WAKE OF THE SFC LOW.

&&

.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

UPDATE...JMW
SHORT TERM...GREIF
LONG TERM...ABE
AVIATION...GREIF/JMW






USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.