Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS62 KRAH 280212
AFDRAH

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
912 PM EST TUE JAN 27 2015

.SYNOPSIS...STRONG LOW PRESSURE OFF NEW ENGLAND WILL PULL FURTHER
AWAY OVERNIGHT AS COLD HIGH PRESSURE WILL BUILD EAST INTO NORTH
CAROLINA. A CLIPPER LOW PRESSURE SYSTEM WILL SWING BY JUST TO OUR
NORTH LATE THURSDAY THROUGH THURSDAY NIGHT. HIGH PRESSURE WILL AGAIN
BUILD INTO OUR AREA FROM THE NORTHWEST ON FRIDAY.

&&

.NEAR TERM /OVERNIGHT/...
AS OF 912 PM TUESDAY...

STRONG NW FLOW IN THE WAKE OF THE DEPARTING LOW PRESSURE SYSTEM WILL
FUNNEL DRY CHILLY AIR INTO CENTRAL NC OVERNIGHT. A PERTURBATION
ROTATING AROUND THE DEEP CYCLONE WILL CROSS OUR REGION OVERNIGHT.
THIS SYSTEM MAY CAUSE A STRATUS DECK TO PERSIST OVER SECTIONS OF
HALIFAX AND EDGECOMBE COUNTIES WHILE PATCHY CIRRUS MAY AFFECT THE
REST OF THE REGION. CLEAR SKIES SHOULD RETURN BY 3-4 AM.

THE COLD AIR ADVECTION WILL YIELD LOW LEVEL THICKNESSES IN THE 1265-
1270M RANGE BY EARLY WEDNESDAY. HISTORICALLY, THESE THICKNESSES HAVE
PRODUCED MIN TEMPS AROUND 20-LOWER 20S. UPSTREAM...MIN TEMPS EARLY
TUESDAY MORNING WERE IN THE MID TENS-LOWER 20S IN THE COAL FIELDS OF
EASTERN KY (WHERE OUR AIR PARCELS ARE ORIGINATING). HOWEVER
ATMOSPHERE OVER CENTRAL NC EXPECTED TO REMAIN WELL-MIXED THROUGH
MOST OF THE NIGHT (AS EVIDENT OF THE GUST 20-25MPH BEING REPORTED AT
A FEW SITES ACROSS THE NORTHERN PIEDMONT), POSSIBLY DECOUPLING BY 4-
5 AM. THUS...THE WINDS MAY AID TO KEEP TEMPS UP A BIT BUT WHEN/IF
THE WINDS DECOUPLE...TEMPS SHOULD PLUMMET IN THE BONE DRY
ATMOSPHERE. HAVE TWEAKED MIN TEMPS A BIT...YIELDING LOWS MOSTLY IN
THE LOW-MID 20S AND NEAR 20 IN THE NORMALLY COLDER LOCATIONS.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 230 PM TUESDAY...

HIGH PRESSURE IS FORECAST TO MOVE OVERHEAD WEDNESDAY INTO WEDNESDAY
NIGHT. SUNNY SKIES AND LIGHT WINDS WILL TEMPER THE CHILLY AIR MASS.
HIGHS ARE EXPECTED TO REACH THE MID TO UPPER 40S (WARMEST SOUTHERN
PIEDMONT). IT APPEARS THAT THE HIGH LEVEL MOISTURE WILL HOLD OFF
UNTIL THURSDAY. THEREFORE... CLEAR SKIES AND LIGHT WINDS SHOULD
LEAD TO LOWS IN THE UPPER TEENS TO LOWER 20S. OPTIMAL RADIATIONAL
COOLING SHOULD LEAD TO LOWS BELOW MOS GUIDANCE... ESPECIALLY OVER
THE CENTRAL PIEDMONT.

HIGH PRESSURE MOVES OFFSHORE AS A SHORT WAVE AND ASSOCIATED SURFACE
FRONT MOVES INTO AND ACROSS THE OHIO VALLEY THURSDAY INTO THURSDAY
NIGHT. WESTERLY FLOW ACROSS THE SOUTHERN STATES WILL QUASH LOW LEVEL
MOISTURE ADVECTION...SO WILL KEEP ONLY A SLIGHT CHANCE POP WITH VERY
LIGHT PRECIP AMOUNTS...A FEW HUNDREDTHS AT MOST...LIMITED TO A
NARROW WINDOW FROM THURSDAY EVENING THROUGH PERHAPS MIDNIGHT.
SOUTHWEST FLOW AHEAD OF THE FRONT WILL ALLOW FOR
WEAK WARM AIR ADVECTION AND HIGHS WILL REACH THE UPPER 40S ACROSS
THE NORTH TO LOWER 50S IN THE FAR SOUTHERN COUNTIES. EXPECT RAPID
CLEARING AFTER MIDNIGHT...BUT MIXING AND LIMITED TIME FOR
RADIATIONAL COOLING WILL MODERATE MINS FROM AROUND FREEZING IN THE
NORTHWEST TO THE MID 30S ELSEWHERE OVERNIGHT.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 230 PM TUESDAY...

AS THE UPPER SHORT WAVE TROF MOVES OFFSHORE...ENSUING NORTHWEST FLOW
WILL MAINTAIN A FLOW OF COOL AIR INTO THE WEEKEND. SURFACE HIGH
PRESSURE WILL MIGRATE OUT OF THE UPPER MIDWEST OVER THE AREA...SO
SKIES WILL BE MOSTLY CLEAR WITH HIGHS IN THE MID AND UPPER 40S ON
FRIDAY COOLING TO THE LOW AND MID 40S SATURDAY AS THE HIGH PRESSURE
NUDGES ARCTIC AIR DOWN THE ATLANTIC COAST. MINS SATURDAY MORNING
WILL BE ON THE COOL SIDE...MOSTLY IN THE LOWER 20S DUE TO EXCELLENT
RADIATIONAL CONDITIONS.

THE HIGH EDGES OFFSHORE SATURDAY NIGHT...WITH A LIGHT SOUTHERLY FLOW
AND INCREASING CLOUD COVERAGE TO KEEP MINS FROM CRASHING AS DEEPLY
SUNDAY MORNING...LOWS SHOULD BE WITHIN A DEGREE OR TWO OF 30. THINGS
ARE MORE INTERESTING/ACTIVE HEADING INTO EARLY NEXT WEEK...WITH
PHASING OF A NORTHERN STREAM SHORT WAVE DIGGING DEEPLY INTO THE
MIDWEST AND THE SOUTHERN STREAM JETSTREAM. THIS WILL INDUCE
CYCLOGENESIS OVER THE OHIO VALLEY SUNDAY NIGHT...RESULTING IN A
STRONG COASTAL LOW IN THE VICINITY OF CAPE COD ON MONDAY. STRONG
WARM AIR AND MOISTURE ADVECTION AHEAD OF THE SYSTEM WILL SPREAD RAIN
INTO WESTERN NORTH CAROLINA BY SUNDAY AFTERNOON...WITH WIDESPREAD
RAIN OVER THE AREA SUNDAY NIGHT. HEAVY SHOWERS...MAYBE A ROGUE STORM
OR TWO...LOOK TO BE A POSSIBILITY AS WELL WITH AN H85 JET OF 50+
KNOTS AND STRONG UPPER DIFFLUENCE IN PHASE MOVING ACROSS THE AREA
OVERNIGHT. HIGHS SUNDAY WILL SHOW A WIDE RANGE...FROM AROUND 40
NORTH TO LOWER 50S IN THE SOUTH IN WARM AIR ADVECTION AHEAD OF THE
FRONT. TEMPERATURES WILL BE SLOWER TO FALL SUNDAY NIGHT WITH A LATE
FRONTAL PASSAGE...AND TEMPS WILL BE ABOVE FREEZING AS THE RAIN ENDS
MONDAY MORNING. HIGHS MONDAY WILL RANGE FROM MID 40S WEST TO AROUND
50 EAST...WITH MINS CRASHING IN COLD AIR ADVECTION MONDAY NIGHT INTO
THE MID 20S WITH SUNNY SKIES AND COOL HIGHS IN THE LOWER 40S ON
TUESDAY.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
AS OF 720 PM TUESDAY...

24 HOUR TAF PERIOD: VFR CONDITIONS AND CLEAR SKIES HAVE RETURNED TO
ALL OF THE CENTRAL NC TAF SITES THIS EVENING. HOWEVER... ANOTHER
QUICK MOVING MID LEVEL DISTURBANCE WILL CROSS THE REGION LATE THIS
EVENING INTO THE EARLY MORNING HOURS OF WEDNESDAY. THIS MAY ALLOW
FOR A BRIEF PERIOD OF OF LOW END VFR AND/OR HIGH END MVFR CIGS AT
KRDU/KRWI/KFAY. GIVEN CONFIDENCE IS LOW FOR SEEING ANY SUB-VFR CIGS
HAVE JUST ELECTED TO ADD A TEMPO GROUP WITH SCATTERED CLOUDS IN THE
2500 TO 3000 FT RANGE FOR THE EASTERN TAF SITES MENTIONED ABOVE.

OTHERWISE.... EXPECT VFR CONDITIONS ALONG WITH A NORTHERLY TO
NORTHWESTERLY WIND IN THE 5 TO 11 KT RANGE THROUGHOUT THE 24 HOUR
TAF PERIOD.

LONG TERM: GENERALLY VFR CONDITIONS ARE EXPECTED FOR THE REMAINDER
OF THE WEEK INTO THE WEEKEND... AS THE NEXT COLD FRONT CROSSING THE
AREA LATE THURSDAY NIGHT OR FRIDAY IS EXPECTED TO GENERALLY BE
MOISTURE STARVED AT OUR LATITUDE (ALTHOUGH A BRIEF SHOWER AND/OR
BRIEF SUB-VFR CIGS CANT BE RULED OUT). A MORE POTENT STORM SYSTEM IS
EXPECTED TO APPROACH THE AREA FROM THE SOUTHWEST ON SUNDAY... WITH
PRECIP AND POSSIBLY SUB-VFR CONDITIONS SPREADING INTO THE
AREA/DEVELOPING ON SUNDAY.

&&

.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.

&&

$$

SYNOPSIS...BADGETT
NEAR TERM...WSS
SHORT TERM...BADGETT
LONG TERM...MLM
AVIATION...BSD/BADGETT


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.