623  
FXUS63 KJKL 042100  
AFDJKL  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE JACKSON KY  
400 PM EST SUN DEC 4 2022  
   
SHORT TERM
 
(THIS EVENING THROUGH MONDAY NIGHT)  
ISSUED AT 400 PM EST SUN DEC 4 2022  
 
20Z SFC ANALYSIS SHOWS HIGH PRESSURE OVER KENTUCKY TODAY AND THIS  
HAS KEPT THE WINDS LIGHT, RELATIVE HUMIDITIES LOW, AND PUSHED THE  
HIGH CLOUDS FURTHER SOUTH THROUGH THE STATE. TEMPERATURES ENDED  
UP ON THE COOL SIDE OF NORMAL WITH READINGS CURRENTLY IN THE LOW  
TO MID 40S WHILE DEWPOINTS ARE RUNNING IN THE MID TO UPPER 20S  
MOST PLACES.  
 
THE MODELS REMAIN IN EXCELLENT AGREEMENT ALOFT THROUGH THE SHORT  
TERM PORTION OF THE FORECAST. THEY ALL DEPICT THE MID LEVEL  
PATTERN SHIFTING FROM NORTHWESTERLY TONIGHT TO MORE SOUTHWESTERLY  
BY TUESDAY MORNING. THIS WILL INCREASINGLY BRING IN DEEP LAYER  
MOISTURE TO START THE WORK WEEK WITH JUST SOME WEAK PACKETS OF  
ENERGY FLOWING THROUGH IN THAT STREAM. GIVEN THE VERY SMALL MODEL  
SPREAD DURING THIS TIME HAVE AGAIN FAVORED THE BLENDED NBM  
SOLUTION FOR THE STARTING POINT OF THE FORECAST GRIDS WITHOUT MUCH  
ADJUSTMENT NEEDED.  
 
SENSIBLE WEATHER WILL FEATURE A COOL EVENING AND START TO THE  
NIGHT AS GOOD RADIATIONAL COOLING CONDITIONS LIKELY LEAD TO A  
DECENT RIDGE TO VALLEY TEMPERATURE SPLIT BEFORE THE CLOUDS START  
TO THICKEN UP AND STEADY THE TEMPERATURES A FEW HOURS AFTER  
MIDNIGHT. LOOK FOR SOME RISE TOWARDS DAWN MOST SPOTS WITH THICK  
CLOUDS AND THE APPROACH OF THE FIRST WAVE OF PCPN BRINGING IN  
WARMER CONDITIONS AND MOISTURE. THE MOISTURE WILL EVENTUALLY  
SATURATE DOWN ENOUGH, AND OVERCOME SOME DOWNSLOPING, TO RESULT IN  
SHOWERS REACHING THE SFC BY MID TO LATE AFTERNOON MOST PLACES.  
THIS INITIAL ROUND OF SHOWERS AND OVERRUNNING WILL THEN PROVIDE A  
GOOD SOAKING RAIN MONDAY NIGHT INTO TUESDAY MORNING WITH  
CATEGORICAL POPS IN ORDER. UP TO THREE QUARTERS OF AN INCH OF  
RAINFALL IS EXPECTED FROM THIS MAINLY FAVORING THE CUMBERLAND  
VALLEY AND HEADWATERS - LIKELY SETTING THE STAGE FOR MORE  
SATURATED ANTECEDENT CONDITIONS FOR THE NEXT ROUNDS OF RAIN.  
TEMPERATURES WILL BE WARMER FOR HIGHS MONDAY THAN TODAY WITH MUCH  
MILDER READINGS MONDAY NIGHT - NEARLY STEADY IN THE 40S DURING  
THE RAIN.  
 
DID MAKE SOME ADJUSTMENT TO HOURLY TEMPERATURES TONIGHT TO BETTER  
CAPTURE THE TERRAIN DISTINCTIONS FOR AT LEAST THE FIRST PART OF  
THE NIGHT. AS FOR POPS, MAINLY JUST INCLUDED SOME OF THE CAMS  
SPECIFICS THROUGH TUESDAY MORNING - BETTER HONING IN ON THE  
TIMING OF THE HIGHEST RAIN CHANGES.  
   
LONG TERM
 
(TUESDAY THROUGH SUNDAY)  
ISSUED AT 240 PM EST SUN DEC 4 2022  
 
KEY POINTS:  
 
* SEVERAL DISTURBANCES EXPECTED TO RIDE A QUASI-STATIONARY SURFACE  
BOUNDARY, WHICH WILL BRING SEVERAL RAINFALL OPPORTUNITIES TUESDAY  
THROUGH FRIDAY.  
* STORM TOTAL RAINFALL AMOUNTS OF 2 TO 3 INCHES EXPECTED THROUGH  
THIS TIME.  
* TEMPERATURES AVERAGE ABOVE NORMAL THROUGH THE WORK WEEK, DIPPING  
BACK TO NEAR SEASONAL READINGS THIS WEEKEND.  
 
THE EXTENDED FORECAST CONTINUES TO COME INTO BETTER AGREEMENT, WHERE  
AN UNSETTLED, GLOOMY, AND SOGGY WEATHER PATTERN CAN BE EXPECTED  
THROUGH MUCH OF THIS UPCOMING WEEK. STARTING FIRST ALOFT, EASTERN  
KENTUCKY WILL BE WEDGED BETWEEN AN EXPANSIVE 588 DAM RIDGE DOME  
ACROSS THE CENTRAL GULF OF MEXICO, WHILE A BROAD LONGWAVE TROUGH AND  
A SERIES OF RIDING SHORTWAVES SIT NORTH ACROSS THE HUDSON BAY AND  
THROUGH SOUTHERN CANADA. THIS WILL RESULT IN A SW TO NE ORIENTED  
FLAT FLOW, WHICH WILL BE IN PLACE THROUGH AT LEAST THURSDAY. FURTHER  
WEST, A 548 DAM LOW IS ATOP THE MODOC PLATEAU AND WILL MEANDER EAST  
THROUGH MID WEEK, BRINGING REINFORCING SHOWER CHANCES TO THE REGION  
THURSDAY AND INTO FRIDAY. AT THE SURFACE, THE COLD FRONT THAT  
BROUGHT COOLER TEMPERATURES TO THE AREA (TODAY) WILL RE-ESTABLISH  
ITSELF, BENDING BACK NORTH IN THE FORM OF A WARM FRONT TUESDAY  
MORNING. THETA-E ANALYSIS SUGGESTS THIS BOUNDARY TO STALL JUST TO  
OUR NORTH ACROSS THE OHIO VALLEY, ALLOWING FOR A FOCUS FOR DEEP  
MOISTURE TO ADVECT IN OFF THE GULF. DETERMINISTIC MODELS SUGGEST  
PWATS BETWEEN 1 AND 1.5" THROUGH LATE WORK WEEK, WHICH IS BETWEEN  
THE 75TH PERCENTILE AND 2 STANDARD DEVIATIONS ABOVE THE NORM. IN  
COMPARISON, THE ENS AND GEFS, ALIKE, HIGHLIGHT THE ANOMALOUS  
MOISTURE, WITH MEMBER MEANS SUGGESTING PWATS OVER 200% OF THE NORM  
FOR EARLY DECEMBER. WITH THAT SAID, THE RIDING AREAS OF LOW  
PRESSURE ALONG THE BOUNDARY SHOULD BE PROGRESSIVE ENOUGH TO LIMIT  
MOST HYDRO CONCERNS. RAINFALL RATES SHOULD GENERALLY BE LIGHT TO  
MODERATE AND WITH THE AID OF DRY ANTECEDENT CONDITIONS, SOILS  
SHOULD BE ABLE TO HANDLE THE RAINFALL. THAT SAID, AND MENTIONED IN  
THE PREVIOUS DISCUSSION, BASINS WILL LIKELY SEE AN INCREASE IN  
LEVELS GIVEN THE SATURATED GROUNDS AND ROUNDS OF RAINFALL. THE QPF  
REMAINS LARGELY IN CHECK, WHERE 2 TO 3 INCHES ARE EXPECTED  
THROUGH FRIDAY.  
 
BREAKING THIS DOWN FURTHER, THE WARM FRONT WILL BUILD NORTH TUESDAY,  
ALLOWING FOR SHOWERS TO OVERSPREAD THE AREA FROM S TO N INTO THE  
EARLY MORNING. WITH THE BOUNDARY SITTING NEARBY, AREAS OF LOW  
PRESSURE WILL DEVELOP ALONG IT, BRINGING ROUNDS OF SHOWERS AND THE  
CHANCE FOR A FEW THUNDERSTORMS (TUESDAY THROUGH WEDNESDAY). THE  
UPPER LEVEL PATTERN THEN BEGINS TO EVOLVE BEYOND WEDNESDAY, AS THE  
AFOREMENTIONED CALIFORNIA CLOSED LOW WILL NOW BE TREKKING THROUGH  
THE CENTRAL PLAINS, EJECTING ACROSS THE OHIO VALLEY, AND  
EVENTUALLY MEANDERING OFF THE COAST OF THE CHESAPEAKE BAY AREA  
THIS WEEKEND. HEIGHTS WILL LOWER THROUGH THURSDAY, WHERE A COLD  
FRONT WILL INDUCE WIDESPREAD SHOWERS AHEAD AND ALONG IT AFTER 12Z.  
FROPA WILL BE INTO MIDDAY FRIDAY, BUT UPSLOPE FLOW WILL LEND TO  
LINGERING SHOWER CHANCES, PARTICULARLY ACROSS THE SE INTO EARLY  
SATURDAY MORNING. RISING HEIGHTS ASSOCIATED WITH SHORTWAVE RIDGING  
WILL THEN SLIDE IN SATURDAY, BRINGING TEMPORARILY DRIER AND  
COOLER CONDITIONS THROUGH MUCH OF THE DAY. HAVE HELD OFF ON THE  
REINTRODUCTION OF POPS ASSOCIATED WITH ANOTHER WAVE LATE IN THE  
PERIOD, AS THE NBM SEEMED A BIT PROGRESSIVE COMPARED TO  
DETERMINISTIC AND SOME OF THE ENSEMBLES. NONETHELESS, AN  
OPPORTUNITY FOR CHANCE SHOWERS (30-40%) DOES RETURN INTO SUNDAY  
MORNING.  
 

 
   
AVIATION
 
(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)  
ISSUED AT 1250 PM EST SUN DEC 4 2022  
 
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. LOOK FOR MID AND  
HIGH CLOUDS TO THIN AND SHIFT SOUTH THROUGH THE AFTERNOON. CLOUDS  
WILL THEN INCREASE ONCE AGAIN LATE TONIGHT OUT AHEAD OF THE NEXT  
SYSTEM APPROACHING FROM THE SOUTHWEST. ANY PCPN THREAT FROM THIS  
WAVE WILL LIKELY HOLD OFF UNTIL AFTER THIS AVIATION PERIOD. EXPECT  
WINDS TO AVERAGE AROUND 5 KTS OR LESS THROUGH MONDAY AFTERNOON.  
 

 
   
JKL WATCHES/WARNINGS/ADVISORIES
 
 
NONE.  

 
 

 
 
SHORT TERM...GREIF  
LONG TERM...BB  
AVIATION...GEOGERIAN/GREIF  
 
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