197
FXUS62 KRAH 042013
AFDRAH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
413 PM EDT WED JUN 4 2025
SYNOPSIS
HIGH PRESSURE OFF THE MIDDLE ATLANTIC COAST WILL EXTEND WESTWARD
INTO NC THROUGH THIS EVENING. MEANWHILE, AN AREA OF LOW PRESSURE
WILL DEVELOP NEAR AND JUST INLAND OF THE SOUTHEAST U.S. COAST, THEN
TRACK SLOWLY NORTHEAST ACROSS THE EASTERN CAROLINAS LATER TONIGHT
THROUGH FRIDAY MORNING.
NEAR TERM /THROUGH TONIGHT/
AS OF 330 PM WEDNESDAY...
DEEP DRYNESS WAS OBSERVED IN BOTH THE GSO AND MHX RAOBS THIS
MORNING, AND THE INITIAL RAIN SHIELD THAT WILL BE FALLING FROM
LOWERING HIGH THROUGH MID-LEVEL CEILINGS EARLY TONIGHT WILL HAVE A
DIFFICULT TIME OVERCOMING SUB-CLOUD DRYNESS. WHILE A FEW SPRINKLES
MAY RESULT THIS EVENING, MEASURABLE RAIN IS UNLIKELY TO MATERIALIZE
UNTIL LATER TONIGHT-THU MORNING, WHEN LOW-LEVEL FORCING AND MOISTURE
TRANSPORT INCREASE INTO THE SRN HALF OF CNTL NC, AND PROBABLY INTO
THE TRIANGLE AROUND THE TIME OF THE THU MORNING COMMUTE. LOW
TEMPERATURES IN THE 60S. -GIH
SHORT TERM /THURSDAY AND THURSDAY NIGHT/
AS OF 410 PM WEDNESDAY...
*WET, WITH A RISK OF A SHORT-LIVED TORNADO OR TWO AND ISOLATED
INSTANCES OF FLASH FLOODING
A SHORTWAVE TROUGH FROM THE SRN APPALACHIANS TO THE E-CNTL GULF WILL
DEAMPLIFY WHILE LIFTING NEWD AND ACROSS AND OFFSHORE THE CAROLINAS
AND SRN MIDDLE ATLANTIC. IT WILL BE IMMEDIATELY PRECEDED BY AN AREA
OF DIABATICALLY-AMPLIFIED MID-LEVEL VORTICITY FROM THE AREA OF
PRECIPITATION AND EMBEDDED CONVECTION NOW CENTERED OVER THE SAVANNAH
BASIN, AND AN ASSOCIATED PLUME OF PWS OF AROUND 2.0" AND 150% OF
NORMAL.
AT THE SURFACE, AN AREA OF LOW PRESSURE IS FORECAST TO DEVELOP LATE
TONIGHT FROM THE HEART OF GA TO CNTL SC, THEN TRACK GENERALLY AND
SLOWLY NEWD ACROSS THE SRN PIEDMONT AND WRN SANDHILLS OF NC ON THU
AND CNTL AND NRN COASTAL PLAIN THU NIGHT.
RAIN WILL BECOME INCREASINGLY-WIDESPREAD, AND MODERATE TO HEAVY AT
TIMES OVER THE SRN HALF OF CNTL NC, EARLY THU MORNING, THEN SPREAD
NEWD WITHIN A ZONE OF LOW-LEVEL FRONTOGENESIS AND ISENTROPIC ASCENT
AND MOISTURE TRANSPORT THAT WILL ALL MAXIMIZE ALONG AND IMMEDIATELY
NORTHWEST OF THE TRACK OF THE SLOW-MOVING SURFACE LOW. DESPITE
WIDESPREAD, MULTI-LAYERED CLOUDINESS, SURFACE THETA-E ADVECTION
AHEAD OF THE LOW WILL SUPPORT THE DEVELOPMENT OF WEAK SURFACE-BASED
INSTABILITY. ADDITIONALLY, DESPITE GENERALLY WEAK DEEP LAYER FLOW,
STRONGLY VEERING WIND PROFILES FROM ELY AT THE SURFACE TO WSWLY AT 3
KM WILL SUPPORT CLOCKWISE-CURVED HODOGRAPHS BETWEEN 0-3KM AND 150-
250 M2/S2 EFFECTIVE HELICITY AND SUPPORTIVE OF MINI-SUPERCELLS. SUCH
ENVIRONMENTS, PARTICULARLY ONES WITH LOW LCLS LIKE THAT FORECAST FOR
THURSDAY, ARE CHARACTERISTIC OF TROPICAL TORNADO ENVIRONMENTS AND
ARE SIMILAR TO THAT WHICH SUPPORTED THE BACK-TO-BACK DAYS OF
TORNADOES IN EDGECOMBE CO. IN MAY. RAIN AND STORMS WILL GRADUALLY
EDGE EWD AND OUT OF CNTL NC THU NIGHT, WITH CLEARING AND AREAS OF
FOG, PERHAPS DENSE, POSSIBLE OVER THE FAR NW THROUGH SRN NC
PIEDMONT FRI MORNING.
CLOUDS AND PRECIPITATION WILL OTHERWISE KEEP TEMPERATURES THU ABOUT
8-10 F BELOW AVERAGE AND IN THE 70S, FOLLOWED BY SEASONABLY MILD AND
HUMID LOWS IN THE 60S.
LONG TERM /FRIDAY THROUGH WEDNESDAY/
AS OF 245 PM WEDNESDAY...
KEY POINTS:
- UNSETTLED WEATHER DURING MUCH OF THIS LONG TERM PERIOD WITH LOWEST
RAIN CHANCES ON FRIDAY AND HIGHEST RAIN CHANCES ON TUESDAY. ABOVE-
CLIMO RAIN CHANCES THE REMAINING DAYS.
- TEMPS NEAR TO SLIGHTLY ABOVE NORMAL.
THE LONG TERM PERIOD WILL BE DEFINED BY DAILY, MOSTLY DIURNAL,
SHOWER AND THUNDERSTORM CHANCES EACH DAY, AS SLOWLY-EVOLVING BROAD
UPPER TROUGH TRANSITS ACROSS THE NE QUADRANT OF NORTH AMERICA, ALL
WHILE SENDING SHORTER-WAVELENGTH DISTURBANCES ACROSS THE MID
ATLANTIC AND SOUTHEAST STATES. A SERIES OF RELATIVELY WEAK COLD
FRONTS ACCOMPANYING EACH OF THE UPPER SHORT WAVES WILL APPROACH AND
STALL OR FIZZLE OUT ACROSS OUR AREA DURING THIS TIME, ALL OF WHICH
WILL CONTRIBUTE THE DAILY SHOWER/TSTM CHANCES.
OF THE DAYS IN THE LONG TERM, THE DRIEST DAY (POP <20%) WILL BE
FRIDAY, THANKS TO OUR AREA BRIEFLY BEING IN THE SUBSIDENT REGION
BEHIND THE DEPARTING SFC LOW THAT WAS NOTED IN THE NEAR AND SHORT
TERM PERIODS. THE WETTEST DAY (POPS IN THE LIKELY RANGE) MAY END UP
BEING TUESDAY GIVEN THAT THE SHARPEST OF THE SHORT WAVES WILL BE
PASSING BY THAT DAY. POPS FOR THE REMAINING DAYS IN THE LONG-TERM
WILL GENERALLY BE IN THE CHANCE RANGE, AGAIN, MAINLY DIURNAL IN
NATURE.
DAYTIME TEMPS DURING THIS TIME WILL GENERALLY BE AROUND OR SLIGHTLY
ABOVE NORMAL (HIGHS IN THE MID TO UPPER 80S) GIVEN THAT THE LONGWAVE
TROUGH AXIS AND FRONTAL POSITIONS WILL REMAIN MAINLY TO OUR WEST
MOST OF THE PERIOD. NIGHT-TIME LOWS WILL BE SEVERAL DEGREES ABOVE
NORMAL (UPPER 60S TO AROUND 70) DUE TO THE EXTENSIVE CLOUD COVERAGE.
FINALLY, FOR THOSE WITH OUTDOOR ACTIVITIES THIS WEEKEND... THE BEST
CHANCE FOR RAIN BOTH SATURDAY AND SUNDAY WILL BE MAINLY DURING THE
AFTERNOON AND EVENING HOURS, WHILE THE OVERNIGHT AND MORNING HOURS
SHOULD BE MOSTLY DRY.
AVIATION /18Z TUESDAY THROUGH SUNDAY/
AS OF 132 PM WEDNESDAY...
MOSTLY SCATTERED LOW VFR FAIR-WEATHER CUMULUS, MAINLY OVER THE
PIEDMONT, WILL LINGER THROUGH THE EARLY EVENING AS HIGH CLOUDS OVER
SC SPREAD NORTHWARD. CIGS ARE EXPECTED TO LOWER GRADUALLY AS VERY
LIGHT RAIN SPREADS NORTHWARD, BUT NO VSBY RESTRICTIONS ARE EXPECTED
THROUGH MIDNIGHT. INITIALLY MVFR WILL QUICKLY FALL TO IFR FROM S TO
N OVERNIGHT INTO THURS MORNING, AT THIS TIME RAIN IS EXPECTED TO
BECOME MORE STEADY AND RESULT IN MVFR VSBY AS WELL. POCKETS OF
MODERATE RAIN WILL BE POSSIBLE, WITH GREATEST CONFIDENCE AT FAY,
INT/GSO, RDU THROUGH THE MORNING HOURS.
OUTLOOK: LATE MORNING THROUGH THE AFTERNOON, SHOWERS AND ISOLATED
STORMS WILL BE POSSIBLE, ESPECIALLY AT THE EASTERN TAF SITES (RDU,
FAY, AND RWI). SUB-VFR CONDITIONS WILL SLOWLY CLEAR OUT W TO E THU
NIGHT INTO EARLY FRI MORNING BUT ARE LIKELY TO PERSIST THROUGH
SUNRISE FRI AT RWI. SCATTERED SHOWERS/STORMS WILL BE POSSIBLE AROUND
THE TRIAD TERMINALS FRI AFTERNOON/EVENING. A SERIES OF FRONTS MOVING
INTO AND STALLING OVER THE REGION WILL BRING AN UNSETTLED PERIOD SAT
THROUGH WED FOR SHOWERS/STORMS EACH AFTERNOON AND POTENTIAL FOR SUB-
VFR FOG/STRATUS EACH MORNING.
RAH WATCHES/WARNINGS/ADVISORIES
NONE.
SYNOPSIS...MWS
NEAR TERM...MWS
SHORT TERM...MWS
LONG TERM...NP
AVIATION...SWIGGETT/HARTFIELD
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page