Area Forecast Discussion
Issued by NWS Jackson, KY

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 150020 AAA AFDJKL AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE JACKSON KY 820 PM EDT MON APR 14 2014 .UPDATE... ISSUED AT 820 PM EDT MON APR 14 2014 TWEAKED THE TEMP...DEWPOINT...POP...AND SKY COVER GRIDS TO REFLECT CURRENT CONDITIONS AND TRENDS. HAVE TIMED THE RETURN OF SHOWERS... AND A POSSIBLE THUNDERSTORM...INTO THE AREA AFTER 10 PM SPREADING GRADUALLY EAST JUST AHEAD OF THE COLD FRONT. THIS WILL REACH FAR EAST KENTUCKY LAST...LIKELY NOT UNTIL AFTER 06Z...PER THE LATEST HRRR. THE GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. UPDATE ISSUED AT 620 PM EDT MON APR 14 2014 21Z SFC ANALYSIS SHOWS A POTENT COLD FRONT APPROACHING CENTRAL KENTUCKY IN CONJUNCTION WITH THE DEEP SPRING LOW SPINNING OVER THE EASTERN GREAT LAKES. A WAVE WILL LIFT NORTH ALONG THIS BOUNDARY LATER TONIGHT AND SPREAD...MORE SUBSTANTIAL...PCPN BACK OVER EAST KENTUCKY. ON RADAR...A LARGE AREA OF SHOWERS AND A FEW EMBEDDED THUNDERSTORMS ARE MOVING THROUGH WESTERN KENTUCKY ACCOMPANYING THE COLD FRONT. HERE IN THE EAST WE ARE DRY WITH TEMPERATURES IN THE UPPER 60S AND LOWER 70S ALONG WITH A FEW BREAKS IN THE CLOUD COVER. DESPITE THESE BREAKS...WINDS HAVE BEEN CONTAINED IN THE 10 TO 20 MPH RANGE WITH ONLY OCCASIONAL GUSTS TO 30 MPH. MEANWHILE...DEWPOINTS REMAIN LOWEST THROUGH FAR EAST KENTUCKY WHERE SOME UPPER 40S ARE FOUND WHILE MID 50S EXIST FURTHER WEST. THIS EXTRA BIT OF DRY AIR WILL HELP TO HOLD OFF THE RETURNING RAIN SHOWERS FOR A BIT LONGER. WENT AHEAD AND UPDATED THE FORECAST TO DROP THE LAKE WIND ADVISORY AS THE WINDS ARE RUNNING AROUND 10 MPH BELOW CRITERIA. ALSO ADJUSTED THE FORECAST INTO TUESDAY MORNING FOR TIMING THE SHOWERS...AND POSSIBLY THUNDERSTORMS...INTO THE AREA LATER THIS EVENING AND OVERNIGHT. ALSO ADJUSTED THE WX GRIDS FOR THE SNOW CHANCES LATE TONIGHT AND THROUGH THE DAY TUESDAY. MADE SOME MINOR TWEAKS TO TEMPERATURES AND DEWPOINTS THIS EVENING AND INTO TUESDAY MORNING BASED ON THE CURRENT CONDITIONS...TRENDS...AND THE LATEST MODEL GUIDANCE. HAVE UNDERCUT THE CONSSHORT TEMPERATURES LATE TONIGHT AND EARLY TUESDAY AS IT APPEARS TO BE UNDER DOING THE POST FRONTAL CAA. THESE GRIDDED FORECAST UPDATES HAVE BEEN SENT TO THE NDFD AND WEB SERVERS WHILE THE TEXT PRODUCTS HAVE BEEN UPDATED WITH THE CHANGES DESCRIBED ABOVE. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 340 PM EDT MON APR 14 2014 AFTER COMPARING ALL THE LATEST MODEL DATA TO THE ACTUAL WEATHER CONDITIONS OVER THE PAST FEW HOURS...THE NAM12 BY FAR AND AWAY HAS BEEN HANDLING THINGS THE BEST AND HAD THE BEST INITIALIZATION. THEREFORE...THE NAM12 SOLUTION WAS USED TO CREATE THIS AFTERNOONS FORECAST PACKAGE THROUGH WEDNESDAY MORNING. WITH NO PRECIPITATION ONGOING...AND NOTHING AT ALL APPROACHING FROM UPSTREAM...THE AREA SHOULD REMAIN FREE OF RAIN FOR THE NEXT SEVERAL HOURS. ISOLATED RAIN SHOWERS SHOULD BEGIN POPPING UP AND MOVING INTO THE AREA EARLY THIS EVENING...AS A STRONG COLD FRONT BEGINS TO PUSH EASTWARD TOWARD THE AREA. NUMEROUS RAIN SHOWERS AND A FEW THUNDERSTORMS WILL BE POSSIBLE OVERNIGHT...AS THE FRONT MOVES ACROSS THE AREA. THE PERIOD BETWEEN 4 AND 8Z LOOKS TO BE THE IDEAL TIME FOR ANY THUNDER WE EXPERIENCE AS THAT WILL BE THE TIME OF BEST LOW LEVEL WARM MOISTURE FEED. ONCE THE FRONT MOVES BY...MUCH COLDER AIR WILL QUICKLY SPILL INTO THE AREA BEHIND IT. THIS WILL BE WHEN WE COULD SEE SOME SNOW FLAKES FLYING AND PERHAPS EVEN A BIT OF SLEET. WITH GROUND TEMPERATURES EXTREMELY WARM THE PAST SEVERAL DAYS...AND WITH THE SOILS ALREADY WET FROM RAIN...IT WILL VERY HARD FOR ANY SNOW TO ACCUMULATE. THE ONE EXCEPTION WOULD BE THE HIGHER TERRAIN ALONG THE VIRGINIA AND WEST VIRGINIA BORDERS...WHERE THE TALLEST PEAKS COULD SEE MAYBE UP TO AN INCH OF SNOW. ONCE THE FRONT MOVES ACROSS THE AREA LATER TONIGHT...TEMPERATURES WILL BEGIN FALLING STEADILY THROUGH THE PREDAWN HOURS. TEMPERATURES WILL STILL RISE DURING THE DAY ON TUESDAY...BUT WILL NOT RISE VERY MUCH AS A COLD AIR MASS SETTLES OVER THE AREA. HIGH TEMPERATURES FOR MOST LOCATIONS ON TUESDAY WILL LIKELY STRUGGLE TO REACH 40 DEGREES. THE MOST PRESSING MATTER FOR THIS PERIOD OF THE FORECAST WILL BE THE FRIGID TEMPERATURES WE ARE EXPECTING TUESDAY NIGHT INTO WEDNESDAY MORNING. AN ARCTIC AIR MASS WILL HAVE FULLY SETTLED OVER THE REGION TOMORROW NIGHT...ALLOWING TEMPERATURES TO PLUMMET INTO THE LOW TO MID 20S FOR MOST FOLKS. SOME OF OUR COLDER VALLEYS AND TALLEST MOUNTAIN PEAKS MAY EVEN SEE THE MERCURY DIP INTO THE UPPER TEENS. WITH WINDS GOING NEAR CALM MOST OF THE NIGHT...AND WITH SKIES BEING MOSTLY CLEAR...THE STAGE WILL BE SET FOR A WIDESPREAD KILLING FREEZE EVENT. WIDESPREAD FROST WILL BE POSSIBLE FOR MOST OF THE NIGHT AND INTO EARLY WEDNESDAY MORNING. TEMPERATURES THIS COLD WILL EASILY KILL ANY SENSITIVE OUTDOOR VEGETATION THAT IS LEFT UNPROTECTED. A FREEZE WATCH IS CURRENTLY IN EFFECT TO ADDRESS THIS ISSUE...BUT THIS PRODUCT WILL LIKELY BE UPGRADED TO A FREEZE WARNING BY THE UPCOMING NIGHT SHIFT EARLY TOMORROW MORNING. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 348 PM EDT MON APR 14 2014 THE MODELS START OUT IN GOOD AGREEMENT WITH AN UPPR TROUGH EXITING THE EAST COAST FAIRLY ZONAL FLOW ACROSS THE REST OF THE CONUS. AN UPPER TROUGH AND ASSOCIATED FRONT SYSTEM IS OVER THE DAKOTAS. THIS UPPER TROUGH DEEPENS WITH TIME AND SLOWLY PUSHES A COLD FRONT TOWARD THE AREA. THE FRONT SHOULD BE MOVING ACROSS EASTERN KENTUCKY ON FRIDAY NIGHT. LEFT SOME PRECIPITATION IN THE FORECAST FOR FRIDAY...HOWEVER WOULD NOT BE TOO SURPRISED TO SEE ANY PRECIPITATION TO BE DELAYED UNTIL FRIDAY NIGHT. THIS IS WHERE THE MODES BEGIN TO DISAGREE WITH THE GFS A LITTLE FASTER THAN THE ECMWF...WHICH IS THE PREFERRED MODEL. HIGH PRESSURE BUILDS IN BEHIND THE FRONT AND WILL KEEP THINGS DRY THROUGH THE END OF THE PERIOD. FOR TEMPERATURES...NUDGED THE MODEL BLENDS TOWARD THE NEW ECMWF WHICH WAS TYPICALLY COOLER THAN THE BLEND. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 745 PM EDT MON APR 14 2014 VFR CONDITIONS SHOULD HOLD FOR SEVERAL MORE HOURS BEFORE LOWER CLOUDS AND PATCHY VIS RESTRICTIONS MOVE INTO THE AREA WITH THE RETURN OF SHOWERS AND POSSIBLE THUNDERSTORMS. MVFR CIGS CAN BE EXPECTED CLOSER TOWARDS DAWN AS THE FRONT MOVES ON THROUGH...WITH IFR CIGS POSSIBLE FOR A TIME INTO TUESDAY MORNING. VIS WILL ALSO BE FAIRLY LOW FOR A TIME AS THE RAIN SHOWERS SWITCH OVER TO SNOW IN MOST PLACES AROUND DAWN. CONDITIONS IMPROVE BY MIDDAY TUESDAY AS THE PCPN PULLS OUT AND DRIER AIR MOVES ON INTO THE AREA LIFTING CIGS AND CLEARING ANY VIS ISSUES. SOUTHWEST WINDS OF 10 TO 20 KTS WILL SWITCH TO THE WEST...THEN NORTHWEST...AS A COLD FRONT TRANSITIONS THROUGH THE AREA LATE TONIGHT INTO TUESDAY MORNING. EXPECT THE WINDS TO DIMINISH BY NOON TUESDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... FREEZE WATCH FROM TUESDAY EVENING THROUGH WEDNESDAY MORNING FOR KYZ044-050>052-058>060-068-069-079-080-083>088-104-106>120. && $$ UPDATE...GREIF SHORT TERM...AR LONG TERM...JJ AVIATION...GREIF

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