Area Forecast Discussion
Issued by NWS Jackson, KY

Current Version | Previous Version | Text Only | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS63 KJKL 200901 AFDJKL AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON KY 501 AM EDT MON OCT 20 2014 .SHORT TERM...
-- Changed Discussion --
(TODAY THROUGH TUESDAY) ISSUED AT 359 AM EDT MON OCT 20 2014 THE REX BLOCK PATTERN CONTINUES OVER THE CONUS THIS MORNING...WITH MUCH OF THE EASTERN CONUS BEING INFLUENCED BY A STRONG TROUGHING PATTERN. THIS TROUGH WILL CONTINUE TO BE OUR MAIN WEATHER DRIVER FOR THE SHORT TERM TODAY THROUGH TUESDAY. DURING THE DAY TODAY...A SHORTWAVE EMBEDDED IN THE LONGWAVE PATTERN WILL CONTINUE TO STRENGTHEN AS IT MOVES FROM THE UPPER GREAT LAKES THIS MORNING TO THE LOWER GREAT LAKES BY LATE THIS AFTERNOON AND EVENING. BY TOMORROW NIGHT IT WILL STRENGTHEN INTO A CLOSED LOW...THEN DIVE SOUTHWARD DURING THE DAY TUESDAY...REACHING THE VIRGINIAS BY TUESDAY EVENING. HERE IT WILL STALL OUT BEFORE SLOWLY MOVING UP THE NEW ENGLAND SEA BOARD DURING THE EXTENDED PERIOD. FOR TODAY...AS THE SHORTWAVE STRENGTHENS...IT WILL DRIVE A SURFACE LOW PRESSURE SYSTEM FROM THE UPPER GREAT LAKES TO THE LOWER GREAT LAKES. FROM THIS SURFACE SYSTEM WILL EXTEND A COLD FRONT. AS THE LOW MOVES...THE COLD FRONT WILL SWEEP FROM NW TO THE SE...AND EVENTUALLY TRAVERSE EASTERN KY LATE TONIGHT AND INTO TUESDAY MORNING. AS SUCH...UPPER LEVEL CLOUDS HAVE ALREADY PROTRUDED INTO THE REGION THIS MORNING IN ADVANCE OF THIS SYSTEM. A WEAK SCATTERED LINE OF RAIN SHOWERS IS NOT FAR BEHIND...CURRENTLY MOVING ACROSS MUCH OF NORTHERN OH...IN...AND WESTERN KY. SO FAR THESE SHOWERS ARE SHOWING UP ON THE RADAR AS VERY LIGHT...WITH LITTLE IMPACTS EXPECTED. UNFORTUNATELY...LATEST MODELS ARE HAVING A HARD TIME COMING TO A CONCLUSION ABOUT THE PRECIP AS IT REACHES EASTERN KY AND CONTINUES AHEAD OF THE FRONT TODAY AND TONIGHT. THE EXACT LOCATION OF WHERE THE BEST QPF AND POPS WILL BE LOCATED CONTINUES TO DIFFER FROM MODEL TO MODEL. THIS WAS FURTHER COMPLICATED BY THE LACK OF 0Z DATA WHILE CREATING THE FORECAST DUE TO A NCF ISSUE. THESE TWO ISSUES HAVE LED TO SLIGHT LACK IN CONSISTENCY BETWEEN OFFICES FOR POPS OVER THE NEXT 24 HOURS. TRIED TO MATCH UP AS BEST AS POSSIBLE. REGARDLESS...THIS IS A MOISTURE DEPRIVED SYSTEM...SO ANY RAIN THAT DOES OCCUR IS NOT EXPECTED TO CAUSE MUCH IN THE WAY OF IMPACTS. ONCE THE FRONTAL BOUNDARY MOVES THROUGH US BY TOMORROW MORNING...EXPECT THE RETURN OF A MORE NORTHERLY FLOW PATTERN AND COOLER TEMPERATURES. AFTERNOON TEMPS WILL ONLY TOP OFF IN THE UPPER 50S TO AROUND 60 ONCE MORE. ALTHOUGH THE FRONTAL BOUNDARY WILL HAVE EXITED...THE UPPER LEVEL LOW WILL BE ON ITS TRANSITION SOUTHWARD TOWARDS THE VIRGINIAS...PULLING THE SURFACE LOW PRESSURE SYSTEM WITH IT. STRONG NORTHERLY FLOW WILL ALLOW FOR WRAP AROUND MOISTURE TO CONTINUE TO FLOW INTO EASTERN KY OFF THE BACKSIDE OF THE LOW. THIS MOISTURE WILL BE VERY WEAK...BUT UPSLOPE FLOW IN THE FAR EAST COULD BE ENOUGH TO PRODUCE LIGHT SHOWERS IN THIS AREA BOTH TONIGHT AND THROUGH THE DAY TOMORROW. EXPECT LITTLE IMPACT FROM THIS...WITH ONLY VERY LIGHT ACCUMULATIONS EXPECTED. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 501 AM EDT MON OCT 20 2014 AN UPPER TROUGH AXIS IS FORECAST TO BE OVER THE APPALACHIANS AT THE START OF THE PERIOD...IN THE PROCESS OF FORMING A LARGE CLOSED LOW AT ITS BASE AS IT SLOWLY SHIFTS EASTWARD. AT THE SURFACE...A LARGE LOW PRESSURE SYSTEM IS EXPECTED TO BE MEANDERING NEAR THE MID ATLANTIC COAST. IT WILL PUT OUR LOCAL AREA IN A REGION OF COLD AIR ADVECTION AND UPSLOPE FLOW...FAVORING LOW LEVEL INSTABILITY WITH CLOUDS AND POSSIBLY SHOWERS. AS THE ENTIRE SET-UP SLOWLY SHIFTS EASTWARD...IT SHOULD TAKE ANY SHOWERS WITH IT BY WEDNESDAY. A SURFACE RIDGE WILL THEN BE OUR DOMINANT FEATURE INTO FRIDAY. BY FRIDAY EVENING BOTH THE GFS AND ECMWF INDICATE A SHORTWAVE TROUGH NEARING FROM THE NORTHWEST. THE 00Z ECMWF HAS SOME LIGHT PRECIP WITH THIS ON FRIDAY NIGHT...BUT THIS WAS NOT THE CASE IN THE PREVIOUS RUN...AND THE GFS IS STILL BASICALLY DRY. WILL STICK WITH POPS BELOW THE 20 PERCENT THRESHOLD AT THIS POINT...KEEPING THE FORECAST DRY. A COOL AIR MASS AND SUFFICIENT RADIATING AT NIGHT WILL PRESENT A POSSIBILITY OF FROST FOR THE FIRST FEW NIGHTS...MAINLY IN VALLEYS.
-- End Changed Discussion --
&& .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 143 AM EDT MON OCT 20 2014 CONDITIONS WILL BE MAINLY VFR THROUGH THE AVIATION PERIOD ON THE BACKSIDE OF HIGH PRESSURE RETREATING TO THE NORTHEAST. THERE IS A POTENTIAL FOR PATCHY FOG LATE TONIGHT AT SME AND LOZ...BUT VIS SHOULDN/T GET ANY WORSE THAN MVFR FROM THIS. CIGS WILL LIKELY DEVELOP AND LOWER THROUGH THE AFTERNOON ON MONDAY...BUT LATEST SOUNDINGS ARE SHOWING THE LOWEST CLOUD DECK AROUND 3 TO 4K FEET WITH ONLY SCT CIGS AT BEST. LIGHT AND VARIABLE WINDS TONIGHT WILL AVERAGE AROUND 5 KTS FROM THE SOUTHWEST THROUGH THE DAY MONDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...JMW LONG TERM...HAL AVIATION...JMW

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