Area Forecast Discussion
Issued by NWS Jackson, KY

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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS63 KJKL 010255 AFDJKL AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON KY 1055 PM EDT THU JUL 31 2014 .UPDATE...
-- Changed Discussion --
ISSUED AT 1055 PM EDT THU JUL 31 2014 SEEING A LITTLE CONVECTION IN OUR FAR SOUTHEAST...BEING THE RESULT OF SOME SFC/BOUNDARY LAYER OF CONVERGENCE. APPEARS TO BE SOME UPSLOPE COMPONENT ON THE SOUTH SIDE OF BLACK MOUNTAIN AS WELL WHICH HAS BEEN STRONG ENOUGH TO PRODUCE A COUPLE OF THUNDERSTORM CELLS RIGHT ALONG OR JUST SOUTH OF THE KY/VA STATE LINE. THE VAST MAJORITY OF THE ACTIVITY HAS BEEN OUTSIDE OF OUR CWA...AND THE OCCASIONAL CELL THAT MANAGES TO MOVE INTO KY WEAKENS QUICKLY. BEING OF SUCH AN ISOLD NATURE...DECIDED TO LEAVE ANY MENTION OF THUNDER OUT OF THE GRIDS AND ZONES AND TO ADDRESS THE POTENTIAL WITH A GRAPHICAL NOWCAST PRODUCT. ALSO MADE A FEW MINOR ADJUSTMENTS TO OVERNIGHT LOWS AS THIN CI CANOPY HAS DONE LITTLE TO PREVENT A RAPID DROP OFF OF TEMPS THROUGH THE EVENING...WHICH HAS BEEN MORE DRAMATIC IN THE NORTH AND EAST. HOWEVER...MID LEVEL CLOUDS WILL BE ON THE INCREASE AND ARE BEING PICKED UP NOW AT A FEW OF OUR SOUTHERN STATIONS. INCREASE IN CLOUDS SHOULD HELP KEEP OVERNIGHT LOWS FROM BOTTOMING OUT TOO MUCH AND MAY EVEN TEND TO CAUSE A BIT OF REBOUNDING WHERE CEILINGS MATERIALIZE. OTHERWISE UPDATED THE ZONE PACKAGE TO FRESHEN UP WORDING. UPDATE ISSUED AT 836 PM EDT THU JUL 31 2014 FORECAST IS IN VERY GOOD SHAPE THIS EVENING. MADE SOME MINOR TWEAKS TO THE GRIDS FOR LATEST HOURLY OBS. WILL HOLD OFF ON ANY CHANGES TO THE ZONES UNTIL NEXT UPDATE...WHEN AT A MINIMUM WORDING WILL BE FRESHENED UP TO REMOVE EVENING REFERENCES.
-- End Changed Discussion --
&& .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 355 PM EDT THU JUL 31 2014 19Z SFC ANALYSIS SHOWS A WEAK AREA OF HIGH PRESSURE THROUGH KENTUCKY TO THE MID ATLANTIC STATES. TO THE SOUTH...A COUPLE OF WAVES OF LOW PRESSURE ARE TAKING SHAPE...ONE OVER THE SOUTHERN APPALACHIANS AND ANOTHER NEAR BAYOU COUNTRY IN LOUISIANA. ON RADAR...A FEW SHOWERS HAVE DEVELOPED OVER THE SOUTHERN APPALACHIANS...BUT SO FAR EAST KENTUCKY HAS BEEN CLEAR. ON SATELLITE...THE EARLIER LOW CLOUDS BROKE UP IN THE SOUTH AND A DECENT CU FIELD HAS FORMED OVER THE ENTIRE CWA. THESE CLOUDS HAVE NOT HAMPERED TEMPERATURES MUCH...THOUGH...AS THEY HAVE MADE IT TO THE UPPER 70S AND LOW 80S...SO FAR. WITH THE RETURN OF WARMER AFTERNOON WEATHER...THE DEW POINTS HAVE ALSO CREPT UP SO THAT THEY ARE IN THE MID TO UPPER 50S...AND ALL THE WHILE THE WINDS REMAIN LIGHT AND VARIABLE. THE MODELS ARE IN GOOD AGREEMENT ALOFT AS THE UPPER LOW THAT HAS DOMINATED THE WEATHER OVER THE OHIO VALLEY WILL RETREAT TO THE NORTH THROUGH THE SHORT TERM ALLOWING FOR MORE ENERGY TO MOVE ACROSS THE TENNESSEE VALLEY INTO THE DAY FRIDAY. MORE SIGNIFICANTLY...THOUGH...A MID LEVEL WAVE WILL DROP SOUTHEAST THROUGH THE PLAINS AND INTO THE MID MISSISSIPPI VALLEY FRIDAY NIGHT...STARTING TO CARVE OUT ANOTHER NODE OF THE EASTERN TROUGH THROUGH THE WESTERN OHIO VALLEY BY SATURDAY MORNING. THE ECMWF AND GEM ARE A BIT QUICKER AND FURTHER EAST WITH THIS DEVELOPMENT THAN THE NAM AND GFS. FOR NOW...WILL FOLLOW A GENERAL MODEL BLEND WITH SOME LEANING ON THE SPECIFICS FROM THE HRRR AND NAM12. SENSIBLE WEATHER WILL FEATURE A MILDER NIGHT THROUGH EAST KENTUCKY DUE TO AN INCREASE IN CLOUD COVER AND HIGHER DEW POINTS. THIS WILL ALSO LIKELY LIMIT THE FOG DEVELOPMENT TO JUST THE DEEPEST VALLEYS. IN ADDITION TO THE CLOUDS...A FEW SHOWERS WILL BE POSSIBLE LATER TONIGHT ACROSS THE EASTERN PARTS OF THE AREA WITH MORE SUBSTANTIAL RAINS EXPECTED LATER FRIDAY...PRIMARILY IN THE FAR EAST. THUNDER WILL BE A POSSIBILITY LATER FRIDAY AND INTO THE NIGHT AS A COUPLE OF SFC WAVES PASS THROUGH THE AREA. HAVE GONE WITH JUST ISOLATED THUNDER CHANCES...THOUGH...AS THE INSTABILITY WILL BE LESS THEN OPTIMAL FOR WIDESPREAD STORMS INTO SATURDAY MORNING. THE CLOUDS TONIGHT AND AGAIN FRIDAY NIGHT WILL ALSO LIMIT THE RIDGE AND VALLEY TEMPERATURE DIFFERENCES SO HAVE MINIMIZED THESE. LIKEWISE...TEMPS WILL BE TEMPERED BY THE CLOUDS AND PCPN DURING THE DAY FRIDAY. STARTED WITH THE BC/CONSSHORT FOR THE T...TD...AND WIND GRIDS THROUGH THE FIRST 24 HOURS AND THEN PLUGGED IN THE CONSALL SUITE FOR THE REMAINDER OF THE SHORT TERM FORECAST. MADE SOME SMALL ADJUSTMENTS TO LOW TEMPERATURES TONIGHT AND FRIDAY NIGHT FOR SOME MINOR RIDGE TO VALLEY SPLITS. AS FOR POPS...ENDED UP CLOSER TO THE MAV NUMBERS FROM LATER TONIGHT THROUGH SATURDAY MORNING RATHER THAN THE HIGH MET ONES TONIGHT AND LOW VALUES FOR FRIDAY. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 300 PM EDT THU JUL 31 2014 GENERALLY SPEAKING OUR WEATHER WILL BE UNDER THE INFLUENCE OF A MEAN EASTERN CONUS TROUGH THROUGH THE PERIOD. EXCEPTION WILL BE A SHORT WINDOW OF TIME...DYS 6/7...WED/THUR OF NEXT WEEK WHERE FLOW ALOFT WILL BE ANTICYCLONIC TO ZONAL IN NATURE. THIS PERIOD OF SHORT WAVE RIDGING WILL PROVIDE OUR WARMEST WEATHER OF THE EXTENDED...ALLOWING TEMPS TO RISE TO MORE NORMAL SUMMERTIME LEVELS AND HIGHER DURING THE LATTER HALF OF THE FORECAST. MODELS ARE SHOWING A DECENT ENOUGH CONSENSUS IN SOLUTIONS WHERE DEEP TROUGH OVER THE EASTERN CONUS GRADUALLY LIFTS OUT OF THE AREA BY LATE DY5...TUE. ADDITIONAL ENERGY DROPS OUT OF CANADA BY LATE WEEK...JUST BEYOND THE EXTENDED FORECAST WINDOW...EFFECTIVELY CARVING OUT A NEW EASTERN CONUS TROUGH. HOWEVER...CONSIDERABLE DISAGREEMENT EXISTS BETWEEN THE GFS AND A MORE CONSISTENT ECMWF WITH RESPECT TO AMPLITUDE/STRUCTURE OF THE LATTER TROUGH. ECMWF ACTUALLY DEVELOPS A STACKED UPPER LEVEL LOW OVER THE SOUTHERN OHIO VALLEY REGION WHILE THE GFS ADVERTISES A LOWER AMPLITUDE TROUGH WITH ITS PARENT LOW NORTH OF THE GREAT LAKES. FOR SENSIBLE WEATHER...ENERGY ROUNDING THE BASE OF DEEP EASTERN CONUS TROUGH WILL KEEP A THREAT OF MAINLY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS IN THE FORECAST THROUGH ROUGHLY THE FIRST 30 HOURS OF THE EXTENDED. THEN WE WILL SEE WARMER AND DRYER WEATHER THROUGH THE MID TERM. POTENTIAL FOR RAIN RETURNS AT THE END OF THE FORECAST PERIOD WITH APPROACH OF ANOTHER SYSTEM FROM THE WEST BY DY7...THU. WE CAN EXPECT A MODERATION OF TEMPERATURES THROUGH THE EXTENDED...PEAKING OUT CLOSE TO 90 FOR AFTERNOON HIGHS BY NEXT WED...AND POSSIBLY THURSDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 836 PM EDT THU JUL 31 2014 IN GENERAL EXPECTING VFR CONDITIONS THROUGH THE FORECAST PERIOD. DID INCLUDE SOME MVFR FOG AT LOZ AND SME THROUGH THE PREDAWN TIME FRAME. BUT MID LEVEL DECK WILL BE ROLLING IN DURING THE OVERNIGHT AS WELL WHICH MAY HELP KEEP MUCH OF ANY FOG FROM FORMING. HOWEVER...EXACT TIMING OF MOST SIGNIFICANT CLOUD COVER IS IN QUESTION AND GUIDANCE IS QUITE A BIT MORE PESSIMISTIC WITH VSBYS. THEREFORE STAYED WITH A COMPROMISE SINCE MODEL GUIDANCE HAS BEEN DOING DECENTLY WELL OVER THE LAST TWO NIGHTS. OTHERWISE...DISTURBANCE MOVING THROUGH THE SOUTH AND INTO THE SOUTHERN APPALACHIAN MOUNTAINS WILL SUPPORT SOME SCATTERED SHOWER AND THUNDERSTORM ACTIVITY ACROSS MUCH OF THE AREA FRIDAY. INCLUDED SOME VCTS FOR NOW...LEAVING ROOM/TIME FOR FINE TUNING OF ACTIVITY AT TERMINALS WITH FUTURE TAF ISSUANCE/S. WINDS WILL GENERALLY BE LIGHT...BACKING OUT OF THE EAST/NORTHEAST BY FRIDAY. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...RAY SHORT TERM...GREIF LONG TERM...RAY AVIATION...RAY

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