891
FXUS62 KRAH 210824
AFDRAH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
320 AM EST FRI FEB 21 2025
SYNOPSIS
COLD ARCTIC HIGH PRESSURE CENTERED OVER THE MIDWEST WILL GRADUALLY
WEAKEN AND MODIFY AS IT MOVES INTO THE SOUTHERN APPALACHIANS THROUGH
SUNDAY.
NEAR TERM /TODAY THROUGH TONIGHT/
AS OF 320 AM FRIDAY...
THE PRIMARY SURFACE FEATURE OVER THE EASTERN TWO-THIRDS OF THE
COUNTRY IS A SPRAWLING 1042 MB HIGH PRESSURE CENTERED OVER MISSOURI.
EXCEPT FOR A FEW PASSING HIGH CLOUDS OVERNIGHT ACROSS THE SOUTH,
SKIES SHOULD BE MOSTLY CLEAR. THE PRESSURE GRADIENT BETWEEN THE HIGH
AND THE DEPARTING LOW OVER THE ATLANTIC OCEAN WILL DECREASE THROUGH
THE DAY, ALLOWING SOME WIND GUSTS THIS MORNING UP TO 20 MPH TO
DECREASE THROUGH THE DAY. TODAY'S HIGHS SHOULD RANGE FROM THE UPPER
30S TO THE MID 40S, WHICH WILL CONTINUE TO HELP MELT SNOW/SLEET/ICE
FROM THE LAST TWO DAYS. TONIGHT'S LOWS WILL FALL INTO THE TEENS, AS
LIGHT TO CALM WIND, CLEAR SKIES, AND THE FRESH SNOW COVER SHOULD
ALLOW FOR IDEAL RADIATIVE COOLING CONDITIONS. CAUTION WILL BE NEEDED
FOR ANY DRIVERS OVERNIGHT AS TEMPERATURES SHOULD DROP BELOW FREEZING
SHORTLY AFTER SUNSET, AND ANY WATER ON LOCAL ROADWAYS THAT HASN'T
EVAPORATED WILL FREEZE AGAIN. DESPITE COOLER LOWS, APPARENT
TEMPERATURES/WIND CHILL VALUES WILL BE HIGHER, AND THERE DOES NOT
APPEAR TO BE A NEED FOR A COLD WEATHER ADVISORY.
SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/
AS OF 342 PM THURSDAY...
TO BE COMPLETED SHORTLY.
LONG TERM /SUNDAY THROUGH THURSDAY/
AS OF 342 PM THURSDAY...
AFTER LARGELY ZONAL FLOW ALOFT EARLY SATURDAY, A MID-LEVEL VORTICITY
PERTURBATION WILL DIVE THROUGH THE SOUTHEAST SATURDAY NIGHT INTO
SUNDAY MORNING. A SOUTHERN-STREAM SHORT-WAVE WILL THEN GLANCE BY TO
OUR SOUTH SUNDAY INTO MONDAY. BEYOND MONDAY, A STRONG SHORT-WAVE
WILL DRIVE THROUGH THE OHIO VALLEY AND MID-ATLANTIC TUESDAY INTO
WEDNESDAY, FOLLOWED BY THE ARRIVAL OF A POTENTIALLY DEEPER LONG-WAVE
TROUGH THURSDAY INTO FRIDAY.
CHILLY SFC HIGH PRESSURE WILL SETTLE OVER CENTRAL NC SATURDAY BEFORE
SHIFTING OFFSHORE THROUGH SUNDAY MORNING. THIS WILL PROMOTE DRY BUT
CHILLY WEATHER WITH HIGHS PEAKING IN THE MID TO UPPER 40S. LOW-
LEVEL THICKNESSES ARE EXPECTED TO INCREASE SOME SATURDAY NIGHT,
WHICH SHOULD PROMOTE A BIT WARMER OVERNIGHT LOWS IN THE MID TO UPPER
20S.
SSELY RETURN FLOW AROUND THE OFFSHORE SFC HIGH WILL PROMOTE SOME
MODERATION IN TEMPERATURES SUNDAY, WITH HIGHS REACHING THE MID TO
UPPER 50S. GUIDANCE SUGGESTS THAT A COASTAL WAVE ASSOCIATED WITH THE
AFOREMENTIONED SOUTHERN STREAM SHORT-WAVE MAY DEVELOP SUNDAY NIGHT
INTO MONDAY MORNING. HOWEVER, ENSEMBLE GUIDANCE IS IN GOOD AGREEMENT
LARGELY SHUNTING ALL ANOMALOUS MOISTURE ASSOCIATED WITH THIS SYSTEM
TO OUR SOUTH AND OFFSHORE. AS SUCH, WILL CONTINUE TO HIGHLIGHT A DRY
FORECAST THROUGH EARLY TUESDAY. A SECONDARY SHORT-WAVE WILL DIVE
INTO THE MID-ATLANTIC TUESDAY INTO WEDNESDAY. WHILE THE NBM CAME IN
MOSTLY DRY FOR OUR AREA TUESDAY EVENING, THERE WAS ENOUGH SIGNAL IN
THE ENSEMBLE PROBABILITIES FOR MEASURABLE RAINFALL TO WARRANT
SLIGHT CHANCE POPS ACROSS OUR NORTHERN AREAS TUESDAY
AFTERNOON/EVENING (FORECAST SOUNDINGS ALSO CONCUR THAT ENOUGH
SATURATION MAY BE PRESENT TO PRODUCE LIGHT RAIN ALONG THE NC/VA
BORDER). OVERALL THOUGH, THIS SHOULD BE A NON-IMPACTFUL EVENT.
AS WE PIVOT TO MID TO LATE WEEK, ENSEMBLES ARE IN DECENT AGREEMENT
SUGGESTING A DEEPER LONG-WAVE TROUGH MAY DIG AND LIFT ACROSS THE
EASTERN SEABOARD. THERE'S A BIT OF DISAGREEMENT WRT TO TIMING, BUT
ANOMALOUS MOISTURE AND ENHANCED PRECIPITATION CHANCES SHOULD START
TICKING UP THURSDAY INTO FRIDAY. FOR NOW, STUCK WITH THE RAW NBM
OUTPUT INCREASING RAINFALL CHANCES TO HIGH-END CHANCE POPS BY
THURSDAY AFTERNOON. DETAILS TO FOLLOW AS WE GET CLOSER TO MIDDLE OF
NEXT WEEK.
AVIATION /05Z FRIDAY THROUGH TUESDAY/
AS OF 1210 AM FRIDAY...
TAF PERIOD: HIGH CONFIDENCE IN VFR CONDITIONS THROUGH THE NEXT 24
HOURS. THERE SHOULD BE LITTLE MORE THAN A PASSING HIGH CLOUD. MODELS
HAVE BEEN TRENDING DOWN WITH MODEL GUSTS FOR LATE FRIDAY
MORNING/AFTERNOON, AND HAVE TRENDED VALUES DOWN WITH THE 06Z TAF
PACKAGE. IF THE TREND CONTINUES, MAY EVEN BE ABLE TO REMOVE THE
GUSTS AT EASTERN SITES WITH THE 12Z PACKAGE.
OUTLOOK: VFR CONDITIONS ARE EXPECTED INTO NEXT WEEK, WITH A SLIGHT
CHANCE OF SHOWERS ENTERING THE FORECAST FOR TUESDAY.
RAH WATCHES/WARNINGS/ADVISORIES
WINTER WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NCZ007>011-
023>028-040>043-076>078.
COLD WEATHER ADVISORY UNTIL 10 AM EST FRIDAY FOR NCZ011-027-028-042-
043-073>078-083>086-088-089.
SYNOPSIS...BLAES
NEAR TERM...GREEN
SHORT TERM...
LONG TERM...LUCHETTI
AVIATION...GREEN
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page