065
FXUS62 KGSP 051343
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
943 AM EDT SUN APR 5 2026
WHAT HAS CHANGED
UPDATED TO INCREASE POPS THROUGH THE MORNING HOURS AS WELL AS ADJUST
TEMPERATURE TRENDS.
KEY MESSAGES
1. A COLD FRONT BRINGS SOME BENEFICIAL RAIN TO THE REGION
TODAY. WHILE THERE WILL BE A FEW THUNDERSTORMS AND LOCALLY HEAVY
RAINFALL, THE RISK OF FLOODING RAIN OR SEVERE WEATHER REMAINS LOW.
2. FROST REMAINS POSSIBLE ACROSS THE MOUNTAINS AND I-40 CORRIDOR
EACH NIGHT FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT, BUT THE
CHANCE OF A FREEZE CONTINUES TO DROP. PROTECTION OF SENSITIVE
VEGETATION MAY BE REQUIRED TUESDAY NIGHT AND WEDNESDAY NIGHT IN
SOME LOCATIONS.
3. FIRE WEATHER WILL GRADUALLY BECOME MORE OF A CONCERN THROUGH
MID-WEEK AS A DRY AIR MASS SPREADS ACROSS THE REGION. OUTDOOR
BURNING COULD BE DANGEROUS BY WEDNESDAY AFTERNOON DUE TO LOW
RELATIVE HUMIDITY.
DISCUSSION
KEY MESSAGE 1: A COLD FRONT BRINGS SOME BENEFICIAL RAIN TO THE REGION
TODAY. WHILE THERE WILL BE A FEW THUNDERSTORMS AND LOCALLY HEAVY
RAINFALL, THE RISK OF FLOODING RAIN OR SEVERE WEATHER REMAINS LOW.
A LONGWAVE UPPER TROUGH AXIS WILL SWING THRU THE OH VALLEY TO THE
APPALACHIANS TODAY, BRINGING A PLUME OF ANOMALOUSLY HIGH PWATS
ALONG AND AHEAD OF AN ASSOCIATED APPROACHING COLD FRONT. THE DEEP
MOISTURE AND INCREASING SYNOPTIC FORCING ALONG WITH A FEW HUNDRED
J/KG OF MUCAPE ARE RESULTING IN SOME HEAVY DOWNPOURS WITH CONVECTION
SO FAR TODAY. PERSISTENT SWLY UPSLOPE FORCING IS CAUSING SOME
TRAINING AND LOCALLY HEAVY RAINFALL NEAR THE SOUTHERN BLUE RIDGE
ESCARPMENT. SO FAR, RAINFALL AMOUNTS ARE STILL STAYING UNDER FFG,
THANKS TO SUCH DRY ANTECEDENT CONDITIONS. ALSO, WEAK INSTABILITY
AND SHEAR ARE KEEPING CONVECTION UNORGANIZED, RESULTING IN A VERY
LOW SEVERE THREAT.
THE COLD FRONT WILL PUSH INTO THE MOUNTAINS THIS MORNING, THEN
SLOWLY CROSS THE PIEDMONT IN THE AFTN. THE FRONT WILL BRING A BAND
OF MAINLY SHOWERS AND A FEW EMBEDDED THUNDERSTORMS THRU THE MORNING
HOURS, LINGERING INTO THE AFTN ACROSS THE PIEDMONT. CATEGORICAL
POPS LOOKS GOOD, WITH ADDITIONAL QPF RANGING FROM 0.25" TO 0.75"
IN THE PIEDMONT, WITH LOCALLY 1" OR MORE IN THE SWLY UPSLOPE AREAS
OF THE MOUNTAINS AND NEAR THE ESCARPMENT. MODELS GENERALLY AGREE ON
SOME INCREASING SBCAPE AHEAD OF THE FRONT, GENERALLY 500-1000 J/KG,
ALONG WITH INCREASING SWLY BULK SHEAR. THE 00Z CAMS SHOW A LINE
OF CONVECTION SHARPENING UP OVER THE I-85 CORRIDOR AROUND 18Z,
THEN TRACKING EAST AND EXITING BY EARLY EVENING. THE ENVIRONMENT
DOESN'T LOOK TO GET CONDUCIVE TO SEVERE STORMS UNTIL THE LINE IS
EAST OF THE FORECAST AREA. BUT SOME GUSTY WINDS WILL BE POSSIBLE,
IF A LINE DOES FORM. OTHERWISE, IT WILL BE MOSTLY CLOUDY TO OVERCAST
TODAY, WITH TEMPS WARMING TO A FEW DEG ABOVE NORMAL.
MUCH DRIER AIR FILTERS IN BEHIND THE FRONT TONIGHT AS CAA HELPS TO
QUICKLY DROP DEWPOINTS AND TEMPERATURES, WHILE SKIES CLEAR. EXPECTED
OVERNIGHT LOWS TO DROP INTO THE 30S ACROSS THE MOUNTAINS AND 40S
ELSEWHERE. WINDS WILL PICK UP AHEAD, ALONG, AND BEHIND THE FRONT
AS THE DIRECTION TURNS THE DIAL FROM SOUTHWESTERLY AHEAD OF THE
FRONT TO NORTHWESTERLY AND EVENTUALLY NORTHERLY BEHIND THE FRONT
BY DAYBREAK MONDAY. ANY GUST WILL BE LOW-END WITH THE EXCEPTION
OF THE HIGHER ELEVATIONS WHERE GUSTS COULD GET UP TO 45 MPH BEHIND
THE FRONT AND REMAINS LESS THAN 30-35 MPH ELSEWHERE.
KEY MESSAGE 2: FROST REMAINS POSSIBLE ACROSS THE MOUNTAINS AND I-40
CORRIDOR EACH NIGHT FROM MONDAY NIGHT THROUGH WEDNESDAY NIGHT, BUT
THE CHANCE OF A FREEZE CONTINUES TO DROP. PROTECTION OF SENSITIVE
VEGETATION MAY BE REQUIRED TUESDAY NIGHT AND WEDNESDAY NIGHT IN
SOME LOCATIONS.
THE FIRST HALF OF THE UPCOMING WEEK STILL LOOKS LIKE A RETURN TO
MORE NORMAL SPRINGTIME WEATHER. WE SHOULD BE UNDERNEATH A BROAD
MID/UPPER TROF ON MONDAY WITH A WEAKENING SFC HIGH TO OUR WEST. A
SLOWLY PROGRESSIVE NRN STREAM RIDGE WILL PUSH A LARGER CONTINENTAL
SFC HIGH ACROSS THE MIDWEST/GREAT LAKES MONDAY NIGHT AND TUESDAY,
WHICH SHOULD KEEP HIGH TEMPS FAIRLY CLOSE TO NORMAL BOTH MONDAY
AND TUESDAY. HOWEVER, THE TREND ON THE LOW TEMPS CONTINUES TO SHOW
AN UPWARD CREEP, TO THE POINT WHERE IT LOOKS LIKE WE WILL BE IN
THE CLEAR FOR FROST/FREEZE CONCERNS MONDAY NIGHT. A REINFORCING
COLD FRONT SHOULD MOVE THRU EARLY IN THE DAY ON TUESDAY SETTING
THE STAGE FOR A COOLER AIR MASS TO MOVE IN TUESDAY NIGHT. HOWEVER,
THE NEW MODEL BLEND NO LONGER SHOWS ANY 32F OR LOWER IN THE ZONES
THAT HAVE BEEN ACTIVATED FOR FROST/FREEZE PRODUCTS, AND A QUICK
LOOK AT FROST POTENTIAL REVEALS PATCHY AT BEST AND LIMITED TO THE
MOUNTAINS OF NC. BECAUSE OF THE CONTINUED WARMER TREND, WE WILL
HOLD OFF MENTIONING FROST FOR THIS CYCLE. THE SFC HIGH PASSES TO THE
NORTH WEDNESDAY AND THEN OFF THE NEW ENGLAND COAST WEDNESDAY NIGHT,
BUT MAINTAINS WHAT AMOUNTS TO A DRY WEDGE ACROSS THE REGION. HIGH
TEMPS DROP OFF TO FIVE DEGREES UNDER NORMAL FOR WEDNESDAY AND WE
GET ONE MORE COOL NIGHT WEDNESDAY NIGHT. THE FROST POTENTIAL MAY
EXPAND OUT ALONG THE I-40 CORRIDOR TO THE NORTHWEST PIEDMONT IF
THE SFC WINDS DECOUPLE ENOUGH. THOSE WITH SENSITIVE VEGETATION
WILL WANT TO KEEP UP WITH THE FORECAST THRU EARLY THURSDAY.
NOTE THAT THE FROST/FREEZE PROGRAM REMAINS INACTIVE ACROSS THE
NORTHERN MOUNTAINS OF NC, SO ALTHO SOME PARTS OF THE NRN MOUNTAINS
MIGHT GET BELOW FREEZING TUESDAY NIGHT, A FREEZE WARNING WILL NOT
BE ISSUED AND THE FCST WILL BE ALLOWED TO SPEAK FOR ITSELF.
KEY MESSAGE 3: FIRE WEATHER WILL GRADUALLY BECOME MORE OF A
CONCERN THROUGH MID-WEEK AS A DRY AIR MASS SPREADS ACROSS THE
REGION. OUTDOOR BURNING COULD BE DANGEROUS BY WEDNESDAY AFTERNOON
DUE TO LOW RELATIVE HUMIDITY.
AFTERNOON RELATIVE HUMIDITY LOOKS LIKE IT WILL DROP DOWN BELOW
30 PERCENT EACH AFTERNOON BEGINNING ON MONDAY, BUT WINDS WILL BE
MODEST AND GUST POTENTIAL LOOKS LIKE IT WILL STAY WELL BELOW RED
FLAG CRITERIA. BENEFICIAL RAIN TODAY SHOULD PRECLUDE ANY PROBLEMS
ON MONDAY, BUT THE DRY AIR MASS AND A LIGHT NW TO N WIND SHOULD
PROVIDE THE OPPORTUNITY FOR FUELS TO DRY OUT THROUGH TUESDAY
AFTERNOON. BY WEDNESDAY AFTERNOON, EVEN THOUGH HIGH TEMPS WILL
DROP COMPARED TO THE PREVIOUS TWO DAYS, THE LOW RH MIGHT BECOME
MORE PROBLEMATIC IF FUELS DRY OUT AS EXPECTED, BECAUSE OF BETTER
POTENTIAL FOR WIND GUSTS ABOVE 20 MPH. LAND MANAGERS WILL WANT
TO KEEP TRACK OF THIS FORECAST PROBLEM. ONCE THE SFC HIGH SHIFTS
FARTHER OFFSHORE BY THURSDAY, SOME ATLANTIC MOISTURE SHOULD BEGIN
TO RETURN AND AFTERNOON RH RISES ACCORDINGLY.
AVIATION /13Z SUNDAY THROUGH THURSDAY/
AT KCLT AND ELSEWHERE: SHOWERS CONTINUE TO INCREASE IN COVERAGE
ACROSS THE AREA FROM WEST TO EAST AHEAD OF A COLD FRONT. MOIST
SWLY FLOW IS PRODUCING VARIABLE CIGS, FROM IFR TO VFR, BUT MOSTLY
MVFR. CONFIDENCE IS BELOW AVERAGE ON WHAT THE DOMINANT CIG CATEGORY
WILL BE TODAY, AS GUIDANCE IS MIXED. THE COLD FRONT WILL PUSH
THROUGH THE MOUNTAINS THIS MORNING AND ACROSS THE PIEDMONT THIS
AFTN. IT MAY GAIN ENOUGH INSTABILITY FOR SOME TS AS IT CROSSES THE
UPSTATE SITES AND KCLT. WILL CONTINUE TO MENTION TS AT THOSE SITES,
BUT WILL CONVERT TO PROB30S, AS CONFIDENCE HAS DECREASED. PRECIP
SHOULD EXIT TO THE EAST OF ALL THE TAF SITES BY 21-23Z, WITH RAPID
CLEARING OF THE LOW CLOUDS. WINDS WILL REMAIN S/SW AT 5 TO 10 KTS
WITH LOW-END GUSTS THRU THE MORNING. THEY WILL TOGGLE AROUND TO W
AND THEN NW BEHIND THE FRONT THIS MORNING AT KAVL, AND LATE AFTN
IN THE PIEDMONT. WINDS SHOULD LOSE GUSTINESS IN THE PIEDMONT,
BUT REMAIN GUSTY AT KAVL THRU TONIGHT.
OUTLOOK: HIGH PRESSURE SPREADS OVER THE REGION BEHIND THE FRONT
TONIGHT AND LINGERS THRU THE MIDDLE OF WEEK WITH DRY/VFR CONDITIONS
EXPECTED THRU AT LEAST THURSDAY.+
GSP WATCHES/WARNINGS/ADVISORIES
GA...NONE.
NC...NONE.
SC...NONE.
ARK/PM/TDP
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