913  
FXUS63 KLMK 021739  
AFDLMK  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOUISVILLE KY  
1239 PM EST FRI DEC 2 2016  
   
..UPDATED AVIATION DISCUSSION
 
 
   
FORECAST UPDATE
 
 
ISSUED AT 955 AM EST FRI DEC 2 2016  
 
THE MAIN FORECAST CHALLENGE FOR TODAY IS THE LOW CLOUD DECK OVER  
SOUTHERN IN/NORTHERN KY AND HOW FAR SOUTH IT WILL SINK INTO OUR  
REGION. REGIONS THAT REMAIN CLOUDY WILL BE LIMITED TO HIGHS IN THE  
LOWER 40S TODAY. LOCATIONS THAT SEE MAINLY SUNNY SKIES WILL LIKELY  
REACH THE MID 40S TO LOWER 50S.  
 

 
   
SHORT TERM
 
(TODAY THROUGH SATURDAY)  
ISSUED AT 235 AM EST FRI DEC 2 2016  
 
UPPER TROUGHS CROSSING NEW ENGLAND AND THE ROCKIES WILL SANDWICH  
WEAK RIDGING OVER THE PLAINS AND MISSISSIPPI VALLEY. MEANWHILE,  
SURFACE HIGH PRESSURE WILL BUILD FROM THE MIDWEST INTO THE OHIO  
VALLEY. 925-850 RH PROFILES SHOW MOISTURE BEING PULLED DOWN FROM  
CENTRAL CANADA ON THE BACK SIDE OF THE NORTHEASTERN UPPER TROF. THIS  
MOISTURE HAS MANIFESTED ITSELF AS A LARGE SHIELD OF CLOUDS SWEEPING  
FROM THE UPPER PLAINS THROUGH THE GREAT LAKES OVERNIGHT LAST NIGHT.  
SOME CLOUDS MAY FORM IN THIS MOISTURE ALONG AND NORTH OF I-64 TODAY,  
WITH MORE ABUNDANT SUNSHINE TO THE SOUTH. AS A RESULT, WE KEPT HIGH  
TEMPERATURES THIS AFTERNOON IN CHECK ACROSS THE NORTH, IN THE MIDDLE  
40S, WHILE GOING WARMER IN SOUTHERN KENTUCKY WITH LOWER TO MIDDLE  
50S.  
 
AFTER ANOTHER QUIET AND COOL NIGHT TONIGHT WITH LOWS AROUND THE  
FREEZING MARK, HIGH AND MID CLOUDS WILL BEGIN TO ENTER THE REGION  
SATURDAY FROM SOUTHWEST TO NORTHEAST AHEAD OF AN UPPER LOW DIGGING  
INTO NORTHWEST MEXICO. THESE CLOUDS WILL BE HARBINGERS OF MORE  
UNSETTLED WEATHER COMING IN THE LONG TERM.  
 

 
   
LONG TERM
 
(SATURDAY NIGHT THROUGH THURSDAY)  
ISSUED AT 308 AM EST THU DEC 2 2016  
 
THE NORTHWEST MEXICO UPPER LOW AT THE BEGINNING OF THE PERIOD WILL  
EJECT TO CENTRAL TEXAS BY MONDAY MORNING, KENTUCKY TUESDAY MORNING,  
AND OFF THE NEW ENGLAND COAST WEDNESDAY MORNING.  
 
A WEAK WAVE AHEAD OF THE PARENT LOW WILL ADVANCE FROM THE OZARKS TO  
THE OHIO VALLEY SATURDAY NIGHT. LOWERING AND THICKENING CLOUDS  
DURING THE DAY SATURDAY WILL BEGIN TO DROP LIGHT PRECIPITATION  
SATURDAY NIGHT, BEGINNING IN THE BOWLING GREEN REGION IN THE EVENING  
AND PROGRESSING TO THE BLUE GRASS BY EARLY SUNDAY MORNING. THE  
MAJORITY OF THE PRECIPITATION WILL BE RAIN AND WILL BE QUITE LIGHT,  
ON THE ORDER OF A TENTH OF AN INCH IN SOUTHERN KENTUCKY AND EVEN  
LESS NORTH OF THERE. SOME LIGHT SNOW STILL MAY MIX IN WITH THE LIGHT  
RAIN OVER SOUTHERN INDIANA AND NORTH CENTRAL KENTUCKY, THOUGH, AS  
SURFACE TEMPERATURES BOTTOM OUT RIGHT AROUND THE FREEZING MARK.  
 
A WEAK NORTHERN STREAM UPPER TROF WILL CROSS THE GREAT LAKES AND  
OHIO VALLEY SUNDAY AFTERNOON/EVENING WITH PATCHY LIGHT RAIN  
CONTINUING SUNDAY, THEN PULLING OFF TO THE EAST SUNDAY EVENING.  
 
DRIER AIR WILL MOVE IN FOR SUNDAY NIGHT AND MONDAY MORNING, BUT THEN  
DEEP MOISTURE WILL RETURN BY MONDAY AFTERNOON AND CONTINUE THROUGH  
MONDAY NIGHT AS THE DESERT SOUTHWEST UPPER LOW APPROACHES. ALSO, A  
SURFACE LOW WILL SPIN UP OVER THE NORTHWESTERN GULF OF MEXICO AND  
ACCOMPANY ITS 500HPA COUNTERPART NORTH NORTHEASTWARD, BECOMING  
NEARLY STACKED BY THE TIME THE SYSTEM REACHES KENTUCKY.  
PRECIPITATION WILL RETURN, THIS TIME FROM SOUTH TO NORTH AND  
ENTIRELY IN THE FORM OF RAIN, MONDAY EVENING THROUGH THE OVERNIGHT.  
THE BEST CHANCE FOR SIGNIFICANT RAINS WILL BE MONDAY NIGHT, WITH  
PRECIPITATION BECOMING LIGHTER AND GRADUALLY ENDING TUESDAY AS THE  
SYSTEM AND ITS ASSOCIATED MOISTURE PULL AWAY. SOME WEAK ELEVATED  
INSTABILITY SHOWS UP ON SOUNDING PROGS SOUTHEAST OF THE SURFACE LOW  
OVER SOUTHERN KENTUCKY MONDAY NIGHT AND COULD SPARK A FEW RUMBLES OF  
THUNDER. RAINFALL AMOUNTS SHOULD BE IN THE ONE-HALF TO ONE INCH  
RANGE.  
 
BY TUESDAY NIGHT THE NEXT UPPER TROF WILL BE SINKING INTO THE  
AMERICAN ROCKIES, REACHING THE OHIO VALLEY THURSDAY. THOUGH THE  
DETAILS AT THE SURFACE ARE STILL UNCERTAIN, OVERALL THE PATTERN IS  
UNSETTLED AND SUGGESTS PERIODIC CHANCES OF PRECIPITATION. RIGHT NOW  
THE BEST CHANCES APPEAR TO BE WEDNESDAY NIGHT INTO THURSDAY MORNING  
WITH A POSSIBLE COLD FRONTAL PASSAGE. PRECIPITATION TYPE WILL BE  
LIQUID THROUGH AT LEAST WEDNESDAY EVENING. AFTER THAT, IT DEPENDS ON  
HOW QUICKLY COLD AIR CAN SWEEP IN BEHIND THE DEPARTING FRONT.  
 
LOOKING AHEAD A BIT, LATE THIS WEEK AND INTO NEXT WEEKEND (THE 9TH-  
11TH) LOOKS CHILLY WITH MORNING LOWS FRIDAY AND SATURDAY 10 TO 15  
DEGREES COLDER THAN NORMAL.  
 

 
   
AVIATION
 
(18Z TAF ISSUANCE)  
ISSUED AT 1230 PM EST FRI DEC 2 2016  
 
WIDESPREAD LOW CLOUDS EXIST AT THIS TIME FROM CENTRAL IL TO SOUTHERN  
IN TO NORTHERN KY ON NORTHWARD. SDF AND LEX ARE ON THE SOUTHERN END  
OF THESE CLOUDS, WITH BOTH SITES REPORTING MVFR CIGS (3 KFT) AT THIS  
TIME. THE CLOUDS WERE MAKING SOUTHWARD PROGRESS THIS MORNING BUT  
THIS HAS SLOWED. LOOKS LIKE CIGS SHOULD HOLD IN THIS AFTERNOON AT  
SDF AND LEX AND PROBABLY FOR MUCH OF TONIGHT AT LEX. HAVE SCATTERED  
OUT CLOUDS AT SDF THIS EVENING, BUT CIGS COULD HOLD AS SDF SHOULD  
REMAIN ON THE EDGE OF THE CLOUD SHIELD. CLOUDS WILL REMAIN NORTH AND  
EAST OF BWG, WITH VFR CONDITIONS THROUGH THE FORECAST PERIOD.  
 
AT LEAST SCATTERED LOW CLOUDS SHOULD CONTINUE AT SDF AND LEX ON  
SATURDAY WITH CIGS NOT OUT OF THE QUESTION AT LEX. OTHERWISE, MID  
AND HIGH-LEVEL CLOUDS WILL BEGIN STREAMING IN FROM THE SOUTHWEST  
AHEAD OF THE NEXT WEATHER SYSTEM DURING THE DAY.  
 
SURFACE WINDS THIS AFTERNOON WILL BE FROM THE W OR WNW AT 5-10 KTS,  
THEN LIGHT OR CALM TONIGHT, THEN NW TO N AROUND 5 KTS SATURDAY,  
BECOMING NE AT BWG.  
 

 
   
LMK WATCHES/WARNINGS/ADVISORIES
 
 
IN...NONE.  
KY...NONE.  

 
 

 
 
UPDATE...AMS  
SHORT TERM...13  
LONG TERM...13  
AVIATION...TWF  
 
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