407  
FXUS63 KPAH 181228  
AFDPAH  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE PADUCAH KY  
728 AM CDT SAT AUG 18 2018  
   
UPDATE
 
 
ISSUED AT 728 AM CDT SAT AUG 18 2018  
 
UPDATED AVIATION DISCUSSION.  
 

 
   
SHORT TERM
 
(TODAY THROUGH MONDAY NIGHT)  
ISSUED AT 338 AM CDT SAT AUG 18 2018  
 
VERY LITTLE PCPN WAS INDICATED ON RADAR EARLY THIS MORNING AS A  
MID LEVEL SHORTWAVE CONTINUED TO MAKE ITS WAY THROUGH THE PAH  
FORECAST AREA, AS THE ATMOSPHERE WAS AT MAXIMUM STABILIZATION, AND  
FLOW ALOFT WAS WEAK. SURFACE WINDS WERE LIGHT AND GENERALLY OUT OF  
THE SOUTHWEST. WINDS JUST OFF THE SURFACE AND SLOWLY INCREASING  
CLOUD COVER MAY BE JUST ENOUGH TO PREVENT DENSE FOG FROM FORMING  
IN MOST AREAS THROUGH SUNRISE.  
 
IT IS GOING TO TAKE A WHILE FOR THE 700 MB TROF TO MAKE IT THROUGH  
OUR REGION. UNTIL THEN, SOME CLOUDINESS, SCATTERED SHOWERS AND  
EVEN SOME TSTMS WILL STILL BE IN THE FORECAST DURING THE DAYLIGHT  
HOURS FOR WESTERN KY, SOUTHEASTERN IL, AND SOUTHWESTERN IN.  
HIGHEST POPS (CHANCE) WILL BE IN THE SOUTHERN PENNYRILE REGION OF  
KY. THOUGH IT WILL BE HARD AT FIRST TO FIND IT AT THE SURFACE, A  
LOW LEVEL WIND SHIFT TO THE NORTH IS PROGGED TO BEGIN AFTER  
SUNRISE ACROSS SOUTHEASTERN MO AND SOUTHERN IL. WESTERN KY AND  
SOUTHWESTERN IN SHOULD FOLLOW HOURS LATER. SLIGHTLY DRIER AIR IS  
EXPECTED TO FILTER INTO THE REGION FROM THE NORTH, ALLOWING THE  
LOWS TO DROP INTO THE UPPER 60S SUN MORNING.  
 
SKIES SHOULD BE PARTLY CLOUDY SUN, WITH NO PCPN TO SPEAK OF,  
THOUGH THERE WILL BE AN INCREASE IN CLOUDS FROM THE WEST AHEAD OF  
THE NEXT SYSTEM. SUN NIGHT, SHOWERS AND A FEW TSTMS ARE FORECAST,  
ESPECIALLY WEST OF THE MS RIVER, IN THE WARM ADVECTION REGIME  
AHEAD OF A VIGOROUS LOW PRESSURE SYSTEM ENTERING NORTHERN MO. MON  
LOOKS WET AS LOW LEVEL MOISTURE ADVECTION CONTINUES, AND THE  
SYSTEM CENTER PASSES TO OUR NORTH. A WARM FRONT WILL PASS THROUGH  
THE REGION EARLY IN THE DAY. MODEST INSTABILITY AND WIND SHEAR  
ALOFT MAY ALLOW A FEW TSTMS TO BECOME STRONG OR SEVERE IN THE  
AFTERNOON/EARLY EVENING. THE BEGINNINGS OF A DRY SLOT WILL BEGIN  
MON NIGHT, ENDING PCPN WEST OF THE MS RIVER AFTER MIDNIGHT. AT  
THIS TIME, FLOODING DUE TO HEAVY RAIN OVER SIGNIFICANT AREAS DOES  
NOT SEEM LIKELY.  
   
LONG TERM
 
(TUESDAY THROUGH FRIDAY)  
ISSUED AT 338 AM CDT SAT AUG 18 2018  
 
GOOD MODEL AGREEMENT IN THE SYNOPTIC SCALE PATTERN YIELDS HIGH  
CONFIDENCE IN THE LONG TERM PORTION OF THE FORECAST.  
 
STARTING WITH 12Z TUESDAY, AN UPPER LEVEL TROUGH IS FORECAST TO BE  
ORIENTED FROM THE WESTERN GREAT LAKES SOUTH INTO THE MID MISSISSIPPI  
VALLEY. SURFACE LOW PRESSURE OVER THE SOUTHERN GREAT LAKES IS  
PROGGED TO SHIFT NORTHEAST INTO SOUTHEASTERN CANADA BY WEDNESDAY  
MORNING. UNTIL THE PASSAGE OF THE UPPER LEVEL TROUGH, WIDELY  
SCATTERED SHOWERS AND PERHAPS A FEW THUNDERSTORMS WILL REMAIN  
POSSIBLE ACROSS MAINLY EASTERN PORTIONS OF THE AREA ON TUESDAY.  
 
HOWEVER, THE BULK OF THE EXTENDED FORECAST IS DRY AS AN EXPANSIVE  
RIDGE OF SURFACE HIGH PRESSURE MIGRATES EAST FROM THE PLAINS ON  
TUESDAY INTO THE OHIO VALLEY BY THURSDAY. IN THE UPPER LEVELS,  
NORTHWEST FLOW WILL PREVAIL WITH THE AREA SANDWICHED BETWEEN A RIDGE  
OF HIGH PRESSURE OVER THE SOUTHWESTERN STATES AND A TROUGH OF LOW  
PRESSURE IN THE EAST. THIS WILL RESULT IN OUR FIRST REAL TASTE OF  
FALL WITH BELOW NORMAL TEMPERATURES FORECAST THROUGH MUCH OF THE  
PERIOD. SLIGHTLY WARMER TEMPERATURES ARE EXPECTED BY LATE WEEK AS  
THE UPPER LEVEL RIDGE BEGINS TO BUILD EAST WHILE SOUTHERLY FLOW  
DEVELOPS ON THE BACK SIDE OF THE DEPARTING SURFACE HIGH.  
 
GENERALLY ACCEPTED A MODEL CONSENSUS BLEND OF TEMPERATURES THROUGH  
THE PERIOD. HIGHS ARE FORECAST IN THE LOWER 80S TUESDAY THROUGH  
THURSDAY, THEN MIDDLE 80S BY FRIDAY. LOWS SHOULD AVERAGE IN THE  
LOWER 60S MOST NIGHTS, WITH UPPER 50S EXPECTED WEDNESDAY NIGHT.  
 

 
   
AVIATION
 
 
ISSUED AT 728 AM CDT SAT AUG 18 2018  
 
AS A WIND SHIFT CONTINUES TO CROSS THE REGION, INTRODUCING NORTHERLY  
SURFACE WINDS, IFR AND EVEN LIFR CIGS APPEAR TO BE MOST LIKELY SOUTH  
OF THE OH RIVER FOR A FEW HOURS THIS MORNING. MVFR AND BRIEF IFR  
VSBYS ARE POSSIBLE JUST ABOUT ANYWHERE THROUGH 14Z OR SO. OTHERWISE,  
ISOLATED TO SCATTERED SHOWERS AND TSTMS ARE EXPECTED TO DEVELOP EAST  
OF THE MS RIVER DURING THE DAYLIGHT HOURS. THE TAF SITE MOST LIKELY  
TO RECEIVE IFR CIGS THIS MORNING, AND/OR PCPN TODAY IS KOWB, THOUGH  
THIS TAF DOES NOT CURRENTLY INCLUDE THE LOW CIGS DUE TO LACK OF  
CONFIDENCE AT THIS TIME.  
 

 
   
PAH WATCHES/WARNINGS/ADVISORIES
 
 
IL...NONE.  
MO...NONE.  
IN...NONE.  
KY...NONE.  

 
 

 
 
SHORT TERM...DB  
LONG TERM...RJP  
AVIATION...DB  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab KY Page
The Nexlab IL Page
The Nexlab IN Page
The Nexlab MO Page Main Text Page