598
FXUS62 KGSP 201149
AFDGSP
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC
649 AM EST MON JAN 20 2025
SYNOPSIS
ARCTIC HIGH PRESSURE SPREADING OVER THE AREA WILL BRING BITTER
COLD TO THE REGION FOR MOST OF THIS WEEK. A LOW PRESSURE SYSTEM
IS EXPECTED TO TRACK FROM THE NORTHERN GULF OF MEXICO TO JUST OFF
THE SOUTHEAST COAST BY MID-WEEK, HOWEVER THE POTENTIAL FOR SNOW
APPEARS MINIMAL FOR OUR AREA.
NEAR TERM /THROUGH TONIGHT/
AS OF 640 AM: RADAR RETURNS AND EXTENT OF UPSLOPE CLOUD COVER NEAR
THE NC/TN BORDER HAVE BOTH DIMINISHED OVER THE PAST COUPLE OF
HOURS. IT IS UNCLEAR FROM WEBCAMS NEAR THE BORDER WHETHER LIGHT
SNOW CONTINUES OR WHETHER WE ARE SEEING ONLY BLOWING SNOW. NO
DEFINITIVE ACCUMULATION REPORTS SEEN SO FAR, REMAINING MENTIONABLE
CHANCE FOR ACCUMULATING SNOW IS CONFINED TO THE IMMEDIATE BORDER
AREA. FLURRIES MAY CONTINUE THRU THE REST OF THE MORNING WHEREVER
SUFFICIENT CLOUD COVER REMAINS; CLOUDS TOO WILL THIN/DISSIPATE BY
MIDDAY. WINTER STORM WARNING AND ADVISORIES ARE BEING ALLOWED TO
EXPIRE, BUT A SPECIAL WEATHER STATEMENT WILL BE ISSUED TO COVER THE
REMAINING IMPACTS TO TRAVEL, WHICH ARE NOT LIKELY TO IMPROVE VERY
MUCH AT ALL THIS MORNING DUE TO THE COLD TEMPS, PARTICULARLY WHERE
CLOUDS REDUCE INSOLATION. ADJUSTED WINDS/TEMP TRENDS THIS MORNING
PER CURRENT OBS BUT THE FORECAST OTHERWISE REMAINS ON TRACK. NOTE
COLD WEATHER ADVISORIES AND EXTREME COLD WARNINGS REMAIN IN PLACE
FOR NOW, BUT INCOMING SHIFT WILL EVALUATE WHETHER THOSE CAN BE
CANCELLED EARLIER THAN THEIR CURRENT NOON EXPIRATION.
WINDS WILL REMAIN BREEZY TODAY BUT GRADUALLY WILL BECOME LESS
GUSTY. CLEAR SKIES AND SOME DEGREE OF DOWNSLOPING SHOULD ALLOW
TEMPS TO RISE INTO THE 33-35 RANGE ACROSS MOST OF SC AND THE
SOUTHERN TIER OF THE NC PIEDMONT, AND UPPER 30S IN SOME OF THE
LOWER SAVANNAH VALLEY. MOST OTHER LOCATIONS WILL REMAIN BELOW
FREEZING THRU TODAY, AND HIGHER ELEVATIONS MAY ONLY GET TO AROUND
10. LOW MAX RECORD (24, SEE CLIMATE SECTION) COULD BE IN JEOPARDY
AT ASHEVILLE BUT NOT LIKELY AT CHARLOTTE/GSP. WINDS SHOULD BE
LIGHT ENOUGH THAT UNDER THE INITIALLY CLEAR SKIES, DECOUPLING IS
EXPECTED WHICH SHOULD ALLOW MINS TO DROP BELOW THE REGULAR NBM
IN MOST OF THE LOWER ELEVATIONS, CLOSE TO MOS MEAN, RESULTING IN
LOWS RANGING FROM THE LOWER TEENS IN THE PIEDMONT I-40 CORRIDOR,
TO 17-19 IN THE SAVANNAH VALLEY. HIGH ELEVATIONS MAY ACTUALLY BE
WARMER TONIGHT OWING TO SLIGHT WAA OCCURRING TODAY AROUND 850 MB,
NEAR ZERO. RECORD LOWS TONIGHT ARE FROM THE HISTORIC 1985 COLD
OUTBREAK AND ARE FAR OUT OF REACH. HOWEVER, DESPITE LIGHT WINDS,
WIND CHILLS WILL JUST MEET COLD WEATHER ADVISORY CRITERIA OF 10F IN
OUR SOUTHERN TIER OF SC/NC ZONES (CRITERIA ARE LOWER FURTHER NORTH
WHERE COLD AND WINDY WEATHER OCCURS MORE FREQUENTLY). THIS AREA DOES
NOT OVERLAP WITH ANY OF THE HEADLINES FOR THIS MORNING'S COLD, SO WE
WILL PROCEED WITH THE ADVISORY THERE, VALID MIDNIGHT TO 10 AM TUE.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/
AS OF 3:10 AM EST MONDAY...THE SHORT-TERM FCST PICKS UP AT 12Z ON
TUESDAY WITH BROAD UPPER TROFING SHIFTING EAST AND DEAMPLIFYING OVER
THE CENTRAL CONUS AS UPPER RIDGING BUILDS OVER THE WEST COAST. OVER
THE NEXT 24 TO 48 HRS, THE TROF AXIS IS EXPECTED TO PASS OVER OUR
FCST AREA AND THEN LIFT NE AND OFF THE ATLANTIC COAST. IN ITS WAKE,
HEIGHTS REBOUND MARGINALLY ACROSS THE SOUTHEAST AS MORE ZONAL UPPER
FLOW BRIEFLY SETS UP OVER THE REGION. AT THE SFC, HIGH PRESSURE WILL
GET REINFORCED FROM THE WEST LATE TUESDAY INTO EARLY WEDNESDAY. AT
THE SAME TIME, A LOW IS PROGGED TO DEVELOP OVER THE GULF OF MEXICO
AND THEN QUICKLY MOVE NE AND OUT OVER THE ATLANTIC. WITH THE COLD AIR
IN PLACE DURING THAT TIME, IT'S STILL LOOKING LIKE ANY PRECIP THAT
DOES MATERIALIZE WOULD BE SNOW FOR OUR FCST AREA. OVERALL, PRECIP
CHANCES ACROSS OUR CWA HAVE BEEN TRENDING DOWN A BIT OVER THE PAST
24 HRS OR SO. PRECIP IS STILL MORE LIKELY OVER OUR SOUTHERN-MOST
ZONES, BUT ANY AMOUNTS REMAIN MINIMAL AT BEST WITH ONLY A FEW HUN-
DRETHS OF AN INCH POSSIBLE FOR THOSE ZONES. THIS WOULD PRODUCE LESS
THAN HALF AN INCH OF SNOW LATE TUES INTO EARLY WED. OTHERWISE, THE
MAIN CONCERN FOR THE PERIOD WILL BE THE VERY COLD AIRMASS THAT LIN-
GERS THRU THE PERIOD. THIS AIRMASS WILL PRODUCE VERY COLD TEMPERATURES
AND WIND CHILLS, ESPECIALLY ACROSS THE MTNS. HIGH TEMPERATURES WILL
STRUGGLE TO GET ABOVE FREEZING EACH DAY ACROSS ALL BUT OUR SOUTHERN
ZONES. WIND CHILL VALUES AREN'T EXPECTED TO BE AS LOW TUES MORNING
(AS THEY ARE MONDAY MORNING) AS WINDS SHOULD BE WEAKER, HOWEVER WINDS
PICK UP AGAIN EARLY WED MORNING AND PRODUCE ANOTHER ROUND OF VERY COLD
WIND CHILLS EARLY WED.
LONG TERM /THURSDAY THROUGH SUNDAY/
AS OF 2:55 AM EST MONDAY...THE EXTENDED FCST PICKS UP AT 12Z ON
THURSDAY WITH BROAD UPPER TROFING AMPLIFYING AGAIN OVER THE CENTRAL
CONUS AS UPPER RIDGING BUILDS OVER THE WEST COAST. OVER THE NEXT
COUPLE OF DAYS, THE TROF AXIS WILL TRANSLATE EAST AND OVER OUR AREA
AND THEN LIFT OFF THE ATLANTIC COAST WITH FLAT UPPER RIDGING SPREAD-
ING ACROSS THE SOUTHEAST OVER THE WEEKEND TO END THE PERIOD. AT THE
SFC, ELONGATED HIGH PRESSURE WILL STILL BE LINGERING OVER THE SE AS
THE PERIOD BEGINS EARLY THURSDAY. BY LATE THURSDAY, ANOTHER SFC LOW
IS EXPECTED TO DEVELOP JUST OFF THE SE COAST AND THEN QUICKLY MOVE
NORTHWARD AND UP THE ATLANTIC COAST. HOW FAST THIS HAPPENS STILL
REMAINS SOMEWHAT UNCLEAR AMONGST THE OPERATIONAL MODELS. AT THE
SAME TIME, ANOTHER TRAILING COLD FRONT OR POSSIBLY MULTIPLE FRONTS
WILL MOVE THRU OUR FCST AREA AND/OR PASS JUST TO OUR NORTH. THESE
FEATURES ARE STILL LOOKING PRETTY DRY AT THIS POINT AND ARE NOT
EXPECTED TO PRODUCE MUCH (IF ANY) QPF ACROSS OUR CWA. TOWARDS THE
END OF THE PERIOD SUNDAY INTO EARLY NEXT MONDAY, A STRONGER AND
SUBSTANTIALLY WETTER LOOKING COLD FRONT WILL APPROACH THE WESTERN
CAROLINAS FROM THE WEST AND COULD BRING MORE WIDESPREAD PRECIP.
THE COLD AIRMASS WILL STILL BE IN PLACE AS THE PERIOD BEGINS, BUT
WILL GRADUALLY MODIFY/WARM AS THE PERIOD WEARS ON. TEMPS ARE STILL
EXPECTED TO REMAIN WELL-BELOW CLIMATOLOGY THRU FRIDAY, BUT SHOULD
WARM TO NEAR-NORMAL, IF NOT SLIGHTLY ABOVE, OVER THE WEEKEND AND
INTO EARLY NEXT WEEK.
AVIATION /12Z MONDAY THROUGH FRIDAY/
AT KCLT AND ELSEWHERE: VFR. -SHSN WILL CONTINUE EARLY THIS
MORNING ALONG THE TN BORDER AND MAY BE SEEN AT TIMES AT KAVL ALONG
WITH ASSOCIATED UPSLOPE CLOUDS NEAR MVFR THRESHOLD. MOISTURE IS
DIMINISHING IN THE UPSLOPE LAYER AND THE THREAT OF MVFR CIG OR VSBY
IS EXPECTED TO END BEFORE DAYBREAK. A FEW CLOUDS ARE ALSO SEEN ON
OBS IN THE FOOTHILLS, NEAR KGMU AND KHKY AND WILL DISSIPATE IN SAME
TIMEFRAME. NW WINDS THIS MORNING WITH SOME GUSTS POSSIBLE; GUSTS
NOT APPEARING TO BE AS STRONG AS DEPICTED IN GUIDANCE. SKC TODAY
WITH WINDS WEAKENING AND VEERING TO N/NE EXCEPT AT KAVL. FEW-SCT
CIRRUS WILL RETURN TONIGHT.
OUTLOOK: VFR AND DRY MOST OF THE WEEK THANKS TO THE ARCTIC AIRMASS
LINGERING INTO MUCH OF THE WEEK. EXCEPTIONALLY COLD TEMPERATURES ARE
EXPECTED THROUGH WEDNESDAY NIGHT. CHANCE OF SNOW TUESDAY EVENING
INTO TUESDAY NIGHT PRESENTLY APPEARS NO BETTER THAN ABOUT 30%
BUT CONFIDENCE STILL LOW ON THE DEGREE OF IMPACT, IF ANY.
CLIMATE
RECORDS FOR 01-20
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 69 1906 24 2009 53 1954 -13 1985
1890
KCLT 71 1951 30 1983 53 1890 -2 1985
1929 1893
1927
KGSP 72 1933 30 1983 56 1922 1 1985
RECORDS FOR 01-21
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 72 1927 8 1985 59 1927 -16 1985
KCLT 73 1935 24 1985 58 1954 -5 1985
KGSP 73 1927 26 1985 59 1933 -4 1985
RECORDS FOR 01-22
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 73 1932 21 1960 59 1933 0 1970
KCLT 74 1937 29 1970 60 1906 5 1970
KGSP 72 1938 31 1970 58 1933 3 1893
1921
RECORDS FOR 01-23
MAX TEMPERATURE MIN TEMPERATURE
STATION HIGH LOW HIGH LOW
------- ---------- ---------- ---------- ----------
KAVL 73 1927 20 2005 54 1999 1 1936
1936
KCLT 75 1927 27 1970 59 1999 9 2003
KGSP 73 1974 30 1970 58 1999 5 1893
1927
GSP WATCHES/WARNINGS/ADVISORIES
GA...COLD WEATHER ADVISORY UNTIL NOON EST TODAY FOR GAZ010-017-018-
026.
NC...COLD WEATHER ADVISORY UNTIL NOON EST TODAY FOR NCZ033-035-
048>053-058-059-062>065-501>510.
EXTREME COLD WARNING UNTIL NOON EST TODAY FOR NCZ033-048>053-
058-059-062>064.
COLD WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM EST
TUESDAY FOR NCZ071-072-082.
SC...COLD WEATHER ADVISORY UNTIL NOON EST TODAY FOR SCZ101>103.
COLD WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM EST
TUESDAY FOR SCZ009>014-019-107.
SYNOPSIS...WIMBERLEY
NEAR TERM...WIMBERLEY
SHORT TERM...JPT
LONG TERM...JPT
AVIATION...WIMBERLEY
CLIMATE...GSP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page