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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 280238
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
938 PM EST TUE JAN 27 2015

.SYNOPSIS...
STRONG LOW PRESSURE AFFECTING NEW ENGLAND WILL CONTINUE TO MOVE
NORTH AS HIGH PRESSURE BUILDS INTO THE CAROLINAS TONIGHT THROUGH
THURSDAY. A COLD FRONT WILL MOVE ACROSS THE EASTERN CAROLINAS
THURSDAY NIGHT. MOISTURE WILL RETURN TO THE REGION ON SUNDAY AHEAD
OF A STRONG COLD FRONT THAT WILL CROSS THE AREA LATE SUNDAY NIGHT.
CANADIAN HIGH PRESSURE WILL BUILD OVER THE SOUTHEAST EARLY NEXT
WEEK.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
AS OF 930 PM TUESDAY...CLEAR SKIES FOR THE MOMENT OVER THE EASTERN
CAROLINAS BUT A FEW CLOUDS ARE ON THEIR WAY AS A VORT MAX DESCENDS
UPON US FROM THE NW. TEMPERATURES HAVE DROPPED TO AROUND FREEZING
MANY LOCATIONS...BUT AN UPTICK IN WINDS ASSOCIATED WITH THE VORT
MAX WILL KICK TEMPS BACK UP A TAD AFTER MIDNIGHT BEFORE DROPPING
BACK DOWN THROUGH THE 20S IN THE EARLY MORNING HOURS. FORECAST
REMAINS ON TRACK...PREVIOUS DISCUSSIONS FOLLOW:

LAST OF THE CLOUDS HAVE FINALLY LEFT THE CAPE FEAR REGION AND
TEMPERATURES ARE NOW PLUNGING WITH THE SUNSET AS A RESULT. IN
FACT...THE LOWEST TEMPERATURES IN THE FORECAST AREA ARE NOW FOUND
IN THE CAPE FEAR REGION IN THE UPPER 30S. HAVE MADE ONLY MINIMAL
CHANGES TO THE GRIDDED DATABASE BUT NO SUBSTANTIAL CHANGES TO THE
FORECAST HAVE RESULTED. STILL LOOKING FOR A CLEAR AND DRY NIGHT
WITH LOWS IN THE MID TO UPPER 30S. PREVIOUS DISCUSSION FROM THIS
AFTERNOON FOLLOWS:

STUBBORN LOW CLOUDS WILL CONTINUE FOR A COUPLE MORE HOURS ACROSS
SOUTHEASTERN NORTH CAROLINA BEFORE DRY AIR FINALLY SWOOPS IN AND
WINS THE BATTLE. THERE`S QUITE A DIFFERENCE IN TEMPERATURE ACROSS
THE AREA FROM AROUND 50 IN KINGSTREE (SOUTH OF FLORENCE) TO 40 ON
THE BEACHES EAST OF WILMINGTON. NORTHWESTERLY WINDS WILL CONTINUE
THIS EVENING IN THE FLOW BETWEEN STRONG LOW PRESSURE OFF THE NEW
ENGLAND COAST AND HIGH PRESSURE OVER WISCONSIN.

A DEEP AND VERY COLD TROUGH REMAINS ACROSS THE EAST COAST OF THE
UNITED STATES. A VORT MAX CURRENTLY MOVING SOUTH ACROSS OHIO WILL
SWEEP SOUTHEASTWARD INTO THE BASE OF THE TROUGH TONIGHT...BRINGING
ONE FINAL REINFORCING SHOT OF COLD AIR INTO THE EASTERN CAROLINAS.
AT 850 MB THE RENEWED SURGE OF COLD ADVECTION BEGINS SHORTLY AFTER
06Z/1 AM WEDNESDAY WITH 850 MB TEMPS FALLING TO -5C TO -7C BY
DAYBREAK. ONCE ANY LINGERING CLOUDS MOVE OFFSHORE EARLY THIS
EVENING...SKIES SHOULD REMAIN CLEAR OVERNIGHT WITH ONLY LOW CHANCES
FOR SOME SOME THIN STRATOCUMULUS AT THE BASE OF THE SUBSIDENCE
INVERSION LATE TONIGHT.

WITH A GOOD AMOUNT OF WIND OVERNIGHT MY FORECAST LOWS ARE ON THE
HIGH END OF THE MOS GUIDANCE RANGE...26 ALONG THE I-95 CORRIDOR TO
27-30 ALONG THE COAST. WIND CHILL VALUES COULD FALL INTO THE UPPER
TEENS BY DAYBREAK.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...SURFACE HIGH BUILDS IN FROM THE NORTH WED AS 5H
TROUGH PUSHES FARTHER OFF THE EAST COAST. DEEP NORTHWEST FLOW AND
SUBSIDENCE KEEPS PRECIPITABLE WATER VALUES UNDER 0.20 INCH. SUNNY
SKIES WILL PREVAIL WED BUT DESPITE THIS HIGHS WILL STRUGGLE TO REACH
MID 40S ACROSS MUCH OF THE AREA IN THE FACE OF STRONG COLD
ADVECTION. SURFACE RIDGE AXIS MOVES OVERHEAD WED EVENING...BRINGING
AN END TO COLD ADVECTION AND SETTING THE STAGE FOR STRONG
RADIATIONAL COOLING. CALM WINDS AND DEEP DRY AIR SHOULD HELP
MAXIMIZE COOLING WED NIGHT. ONE POTENTIAL ISSUE SHOWING UP IN
FORECAST SOUNDINGS IS AN INCREASE IN MOISTURE AROUND 500 MB. THIS
LAYER WILL NOT RESULT IN ANY CLOUD BUT COULD LIMIT EFFECTIVENESS OF
THE COOLING CLOSER TO DAYBREAK. EITHER WAY LOWS WILL BE WELL BELOW
CLIMO...LOW TO MID 20S.

SURFACE HIGH SHIFTS OFF THE COAST THU UNDER WEAK 5H SHORTWAVE RIDGE.
BRIEF PERIOD OF WARM ADVECTION AHEAD OF THE FRONT WILL PUSH TEMPS
INTO THE 50S BUT MOST AREAS WILL ULTIMATELY END UP SHORT OF CLIMO.
SKIES START OFF CLEAR BUT INCREASING MOISTURE ALOFT AHEAD OF NEXT
SHORTWAVE CREATES A CIRRUS DECK LATE IN THE DAY. DURATION OF SOUTH
TO SOUTHWEST FLOW THU AFTERNOON LIMITS MOISTURE RETURN AHEAD OF THE
FRONT. THINK SOME SHOWERS COLD DEVELOP ALONG THE BOUNDARY BUT THERE
ARE LIMITING FACTORS. MOISTURE WITH THE FRONT IS NOT VERY DEEP AND
THE LOWEST LEVELS REMAIN DRY. SO EVEN IF PRECIP WERE TO DEVELOP HAVE
A HARD TIME BELIEVING MEASURABLE PRECIP WILL OCCUR. COLD AIR DOES
NOT ARRIVE UNTIL THE VERY END OF THE PERIOD...KEEPING LOWS NEAR
CLIMO FRI MORNING.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
AS OF 3 PM TUESDAY...A DYNAMIC AND CHANGEABLE PATTERN FOR THE
EXTENDED PERIOD...WHERE INITIALLY AN UPPER TROUGH AXIS ALONG
THE APPALACHIAN MOUNTAINS EARLY FRIDAY SLIPS OFFSHORE FRIDAY
NIGHT AND BECOMES REPLACED BY A SHORT-WAVE UPPER RIDGE SATURDAY
NIGHT. ANOTHER VIGOROUS TROUGH APPROACHES SUNDAY BRINGING A VERY
GOOD CHANCE OF RAIN SUNDAY NIGHT INTO EARLY MONDAY.

AT THE SURFACE THIS TRANSLATES TO EXITING ISOLATED SHOWERS AT THE
COAST EARLY FRIDAY...AND DRY HIGH PRESSURE OVER THE AREA SATURDAY
THROUGH EARLY SUNDAY. COMPARISON OF THE GFS/ECMWF SURFACE FIELDS
SHOW GOOD AGREEMENT THAT A MODERATELY STRONG COLD FRONT WITH A
HEALTHY GULF MOISTURE TAP WILL APPROACH SUNDAY...BRINGING SOAKING
RAINS SUNDAY NIGHT INTO DAYBREAK MONDAY.

WPC GUIDANCE AND OTHER NUMERICAL DEPICTIONS SUGGEST 0.75-1.25
INCHES OF RAINFALL STORM TOTAL SUNDAY NIGHT THROUGH EARLY MONDAY
AS THE GULF MOISTURE IF LIFTED AHEAD OF ENERGETIC TROUGH AND THE
ATTENDANT COLD FRONT.

&&

.AVIATION /03Z WEDNESDAY THROUGH SUNDAY/...
AS OF 00Z...STRONG LOW PRESSURE OF THE COAST OF NEW ENGLAND WILL
CONTINUE TO SLOWLY PULL AWAY TO THE NORTHEAST. VFR AND NORTHWEST
WINDS WILL BE OBSERVED AT THE TERMINALS OVERNIGHT. A FEW TO
SCATTERED LOW/MID CLOUDS COULD OCCUR OVERNIGHT AS AN IMPULSE PASSES.
AFTER SUNRISE...SUNNY SKIES WITH NORTH WINDS AROUND 10 KTS...
OCCASIONALLY GUSTING TO 16-20 KTS.

EXTENDED AVIATION OUTLOOK...VFR CONDITIONS ARE EXPECTED AT ALL
TERMINALS THROUGH THE WEEKEND...BUT A FEW SHOWERS ARE POSSIBLE
THURSDAY NIGHT WITH A PASSING COLD FRONT.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 930 PM TUESDAY...LATEST OBS CONTINUE TO SHOW SEAS IN THE 3
TO 4 FT RANGE WITH NW WINDS OF 10 TO 15 KTS. STILL EXPECTING A
COLD SURGE OVERNIGHT TO KICK UP WINDS AND SEAS INTO SCEC RANGE.
PREVIOUS DISCUSSION FROM THIS AFTERNOON FOLLOWS:

STRONG LOW PRESSURE OFF THE NEW ENGLAND COASTLINE AND HIGH
PRESSURE OVER WISCONSIN ARE DRIVING NORTHWEST WINDS ACROSS THE
CAROLINAS. THIS WILL CONTINUE OVERNIGHT...WITH A REINFORCING SURGE
EXPECTED TO MOVE SOUTH ACROSS THE AREA AFTER MIDNIGHT. THIS WILL
MAINTAIN WIND SPEEDS NEAR 20 KNOTS THROUGH THE NIGHT...ESPECIALLY
AWAY FROM SHORE. SEAS CURRENTLY 2-3 FEET NEARSHORE AND 4-5 FEET
NEAR 20 MILES OFFSHORE SHOULD CHANGE LITTLE THROUGH THE NIGHT. A
"SMALL CRAFT SHOULD EXERCISE CAUTION" HEADLINE WILL REMAIN ON THE
FORECAST THROUGH THE NIGHT.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 PM TUESDAY...NORTHWEST FLOW AROUND 20 KT TO START THE PERIOD
WILL DECREASE WED AS GRADIENT RELAXES AND COLD ADVECTION SHUTS OFF.
SURFACE RIDGE AXIS MOVES TO THE COAST WED NIGHT WITH WINDS VEERING
TO NORTHEAST AND CONTINUING TO WEAKEN. RIDGE AXIS MOVES OFFSHORE
WITH LIGHT AND VARIABLE WINDS THU. SURFACE HIGH IS QUICK TO DEPART
EAST WITH RETURN FLOW SETTING UP LATE IN THE DAY THU THEN INCREASING
TO A SOLID 20 KT THU NIGHT AS COLD FRONT APPROACHES FROM THE WEST.
FRONT MOVES EAST OF THE WATERS AS PERIOD ENDS AND OFFSHORE FLOW
DEVELOPS FRI MORNING. COLD AIR TRAILS THE FRONT WITH WIND SPEEDS
AHEAD OF AND BEHIND THE FRONT SIMILAR...20 KT OR SO. SEAS 2 TO 4 FT
FOR A MAJORITY OF THE PERIOD BUILD TO 3 TO 5 FT LATE IN THE PERIOD
AHEAD OF THE ADVANCING COLD FRONT.

LONG TERM /FRIDAY THROUGH SUNDAY/...
AS OF 3 PM TUESDAY...FRIDAY MAY NEED A CAUTION STATEMENT FOR 20
KT NNW WINDS AND 5 FOOT SEAS OUTER WATERS. CONDITIONS WILL VASTLY
IMPROVE INTO SATURDAY AS HIGH PRESSURE SETTLES NEARLY OVERHEAD.
MANAGEABLE MARINE CONDITIONS WILL ALSO PREVAIL INTO SUNDAY. WINDS
AND SEAS WILL BEGIN TO INCREASE SUNDAY NIGHT AHEAD OF A MODERATELY
STRONG COLD FRONT AND AN ADVISORY MAY BE NEEDED LATE SUNDAY NIGHT
INTO MONDAY FOR BLUSTERY S WINDS AND AGITATED SEAS.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...III
NEAR TERM...REK/TRA
SHORT TERM...III
LONG TERM...III
AVIATION...MRR
MARINE...REK/TRA/III