071  
FXUS62 KGSP 290803  
AFDGSP  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC  
303 AM EST MON NOV 29 2021  
   
SYNOPSIS
 
 
HIGH PRESSURE WILL CONTROL OUR WEATHER THROUGH THE BETTER PART OF  
THE WEEK, WITH A WARMING TREND AFTER WEDNESDAY. THE NEXT CHANCE  
FOR RAIN MAY NOT COME UNTIL NEXT WEEKEND WHEN THE NEXT FRONT MAY  
IMPACT THE REGION.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
AS OF 220 AM EST MONDAY: A DEEP TROUGH AXIS IS SITUATED EAST OF THE  
FORECAST AREA, ROUGHLY ALIGNED WITH THE COAST AND GRADUALLY DRIFTING  
EAST, AS A DECAYING COLD FRONT SAGS SOUTH AND EAST OF THE CAROLINA  
PIEDMONT. SATELLITE IMAGERY INDICATES A SLUG OF UPSTREAM MOISTURE  
AND IN THE LAST HOUR OR TWO HAS BEGUN TO SHOW EVIDENCE OF THE  
EXPECTED OROGRAPHIC CIRRUS FORMATION JUST TO THE EAST OF THE  
APPALACHIANS. A FEW WIND GUSTS HAVE POPPED UP IN STATION  
OBSERVATIONS, BUT THE BRUNT OF THE WIND GUST THREAT HAS NOT YET  
MATERIALIZED.  
 
HEIGHTS SHOULD GENTLY RISE THROUGH THE PERIOD AS THE TROUGH  
CONTINUES TO LIFT EASTWARD, GIVING WAY TO BROAD RIDGING OUT OF THE  
HIO VALLEY. 850MB FLOW LOOKS TO PEAK AT ABOUT 40-45KTS IN THE NEXT  
FEW HOURS AS DEEP CAA BUILDS IN BEHIND THE FRONT, BUT THIS IS LIKELY  
TO AFFECT ONLY THE HIGHER ELEVATIONS IN THE APPALACHIANS, AS THE  
BOUNDARY LAYER SHOULD BE DECOUPLED ENOUGH TO PREVENT THOSE WINDS  
FROM MIXING DOWN THE SURFACE. A MODEST 6-7MB PRESSURE GRADIENT  
ACROSS THE SPINE OF THE MOUNTAINS SHOULD STEADILY DISSIPATE THROUGH  
THE MORNING AND EARLY AFTERNOON, SO THE SECOND HALF OF MONDAY SHOULD  
SEE WIND GUSTS DROP OFF.  
 
WHILE CAMS DEPICT SOME DEGREE OF LEE TROUGHING WELL  
INTO THE LATE MORNING MONDAY, PROFILES ACROSS THE REGION ARE TOO DRY  
FOR THIS TO MANIFEST AS ANYTHING MORE THAN SOME SCATTERED MID- AND  
UPPER-LEVEL CLOUDS. DOWNSLOPING FLOW SHOULD BOOST AFTERNOON TEMPS  
TOWARD THE HIGH END OF GUIDANCE, THOUGH THIS WILL STILL BE 2-3  
CATEGORIES BELOW NORMAL, AS WELL AS FURTHER DRYING THE MOISTURE-  
STARVED CP AIR FILTERING IN FROM THE NORTHWEST. AFTERNOON RHS WILL  
LIKELY DROP INTO THE MID/UPPER 20S ACROSS THE PIEDMONT AND UPSTATE,  
WELL INTO THE AREA OF CONCERN FOR FIRE DANGER; LUCKILY, THE OVERLAP  
BETWEEN THE DRIEST HUMIDITIES AND GUSTIEST WINDS WILL BE MINIMAL IN  
BOTH SPACE AND TIME. BY EVENING, NW FLOW AND ACCOMPANYING CAA  
SHOULD CEASE, AS LOW-LEVEL FLOW GRADUALLY TURNS SW OVERNIGHT.  
 

 
   
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/
 
 
AS OF 1225 AM EST MONDAY...THE WEAKLY POSITIVE PNA PATTERN LOOKS  
LIKE IT WILL CONTINUE INTO THE MIDDLE OF THE WEEK, WITH THE WESTERN  
CAROLINAS REMAINING NEAR THE BOTTOM OF A BROAD LOW-AMPLITUDE  
MID/UPPER TROF. FOR THE MOST PART, THIS WILL KEEP OUR WEATHER FAIR,  
WHILE THE FAVORABLE ORIENTATION OF A SFC RIDGE ALONG THE GULF  
COAST EXTENDING OFF THE SOUTHEAST COAST SHOULD PROVIDE FOR WEAK  
WARM ADVECTION AND MOISTURE ADVECTION. AS A RESULT, TEMPS WILL  
CLIMB ABOVE NORMAL FOR TUESDAY AND WEDNESDAY. MORE IMPORTANTLY,  
ENOUGH OF AN UPWARD BUMP IN DEWPT IS EXPECTED TO BRING AFTERNOON  
MIN RH INTO THE 30 PCT RANGE TUESDAY AND 40 PCT RANGE WEDNESDAY,  
TEMPORARILY ALLEVIATING SOME OF OUR FIRE WEATHER CONCERNS. WHERE  
THIS COULD ALL GO WRONG IS ACROSS THE NRN TIER, OWING TO A STREAM OF  
MID-LEVEL VORTS MOVING PAST ACROSS THE OH VALLEY/MID-ATLANTIC. MODEL  
GUIDANCE KEEPS THIS ACTIVITY TO OUR NORTH THROUGH THE PERIOD,  
BUT IT WOULDN'T TAKE MUCH OF A SOUTHWARD SHIFT TO BRING SOME OF  
THE FORCING DOWN INTO OUR AREA, ESPECIALLY WITH THE FINAL WAVE IN  
THE TRAIN WEDNESDAY NIGHT. GUIDANCE DEVELOPS SOME WESTERLY UPSLOPE  
PRECIP AROUND DAYBREAK THURSDAY, BUT JUST TO OUR NORTH. AT ANY RATE,  
TEMPS SHOULD BE WARM ENOUGH THAT ANY PRECIP WOULD BE LIGHT RAIN.  
 

 
   
LONG TERM /THURSDAY THROUGH SUNDAY/
 
 
AS OF 235 AM EST MONDAY...THE SECOND HALF OF THE WEEK CONTINUES  
TO FEATURE A WARMING TREND AS THE UPPER PATTERN DEAMPLIFIES AND  
HEIGHTS RISE OVER THE CAROLINAS. WE END UP IN THE FAST-MOVING  
CONFLUENCE OF THE SPLIT FLOW ALOFT BY FRIDAY. WHETHER OR NOT  
THIS PERMITS A DRY COLD FRONT TO PASS LATE IN THE WEEK MIGHT NOT  
MATTER MUCH. TEMPS WILL BE WELL ABOVE NORMAL, PERHAPS MORE THAN  
TEN DEGREES, FOR HIGHS THURSDAY AND FRIDAY, WITH HIGH PRESSURE  
IN CONTROL OVER THE SOUTHEAST. SOME ENERGY COMING THROUGH THE SRN  
BRANCH OF THE SPLIT COMPLICATES THE ISSUE, BUT CONFIDENCE IS LOW AS  
THESE FEATURES ARE DIFFICULT TO PIN DOWN WITH THE TIMING. A CHANCE  
OF PRECIP WILL DEVELOP OVER THE MTNS FRIDAY NIGHT AND SATURDAY,  
WITH TEMPS TOO WARM FOR ANYTHING BUT RAIN. HOW THE WEAK SRN STREAM  
SYSTEM INTERACTS WITH A NRN STREAM SHORT WAVE HAS AN IMPACT ON THE  
FCST FOR THE REST OF NEXT WEEKEND. THE GFS TAKES A SFC LOW ACROSS  
THE CUMBERLAND PLATEAU AND CENTRAL APPALACHIANS WHICH WOULD BRING  
A SWATH OF PRECIP INTO THE FCST AREA SUNDAY NIGHT, WHILE THE ECMWF  
FAVORS A LESS-INTERACTIVE SOLUTION WITH LOW PRESSURE ALONG THE GULF  
COAST BY MONDAY MORNING AND SFC HIGH PRESSURE IN A FAVORABLE COLD  
AIR DAMMING CONFIGURATION. EITHER WAY, LIGHT PRECIP WOULD BE FALLING  
BY DAYBREAK MONDAY. PATTERN RECOGNITION DOES NOT FAVOR ANYTHING  
BUT RAIN, SO THE HIGH-ELEVATION MIX THAT MIGHT APPEAR OVER THE  
MTNS COMES OUT AS SOMETHING OF A LOW CONFIDENCE ARTIFACT. CHANGES  
ARE LIKELY.  
 

 
   
AVIATION /08Z MONDAY THROUGH FRIDAY/
 
 
AT KCLT AND ELSEWHERE: NW FLOW HAS BEGUN IN EARNEST AT ALL THE TAF  
SITES, AS DRY HIGH PRESSURE BUILDS IN BEHIND A DEPARTING COLD FRONT.  
WIND SPEEDS SHOULD BE SLIGHTLY ELEVATED OVERNIGHT, WITH A CHANCE  
FOR GUSTING AT KAVL AND EVEN TO SOME EXTENT AT KGSP AND KGMU OWING  
TO GAP WINDS. THE GUST THREAT SHOULD GRADUALLY DIMINISH BY LATE  
MORNING/EARLY AFTERNOON MONDAY, AS WINDS OVERALL DIE DOWN AND BECOME  
MORE WESTERLY. SOME OROGRAPHIC CIRRUS IS STILL IN STORE FOR THE LEE  
OF THE MOUNTAINS OVERNIGHT AND INTO MONDAY MORNING, BUT ANY MINIMAL  
CEILINGS WHICH FORM WILL BE VFR BY A LONG SHOT. SKIES SHOULD GO TO  
SKC BY EARLY AFTERNOON AT ALL THE TAF SITES, AND TOWARD MONDAY  
EVENING, A WIND SHIFT TO SW MAY BE IN STORE. WINDS SHOULD REMAIN  
LIGHT THROUGH THE END OF THE PERIOD.  
 
OUTLOOK: DRY HIGH PRESSURE AND VFR CONDITIONS WILL PERSIST THROUGH  
TUESDAY NIGHT. ANOTHER DRY FRONT MAY ARRIVE FROM THE NORTH  
WEDNESDAY THROUGH THURSDAY, AND LINGER NEARBY THROUGH FRIDAY,  
BUT WITH RESTRICTIONS VERY UNLIKELY GIVEN LIMITED MOISTURE.  
 

 
   
FIRE WEATHER
 
 
AN ELEVATED FIRE RISK WILL CONTINUE INTO MONDAY. RELATIVE HUMIDITY  
SHOULD DROP WELL INTO 20S WITH DOWNSLOPE WARMING, WHILE FUELS REMAIN  
VERY DRY. WINDS MAY BE GUSTY ON MONDAY, BUT MAINLY OVER THE  
MOUNTAINS AND ALSO BRIEFLY ACROSS THE PIEDMONT MID TO LATE MORNING  
WHEN MIXING STARTS, YET WINDS WILL LIKELY NOT OVERLAP WITH THE LOWER  
AFTERNOON RH VALUES. THUS, A FIRE DANGER STATEMENT (FDS) REMAINS IN  
EFFECT FOR NE GA AND WESTERN NC MONDAY.  
 

 
   
GSP WATCHES/WARNINGS/ADVISORIES
 
 
GA...FIRE DANGER STATEMENT FROM 10 AM EST THIS MORNING THROUGH THIS  
AFTERNOON FOR GAZ010-017-018-026-028-029.  
NC...FIRE DANGER STATEMENT FROM 10 AM EST THIS MORNING THROUGH THIS  
EVENING FOR NCZ033-035>037-048>053-056>059-062>065-  
068>072-082-501>510.  
SC...NONE.  
 

 
 

 
SYNOPSIS...PM  
NEAR TERM...MPR  
SHORT TERM...PM  
LONG TERM...PM  
AVIATION...MPR  
FIRE WEATHER...  
 
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