Area Forecast Discussion
Issued by NWS Wilmington, NC

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
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 KILM 181908
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
308 PM EDT MON AUG 18 2014

.SYNOPSIS...
A COLD FRONT APPROACHING FROM THE NORTH WILL STALL OVER THE AREA
THROUGH MID-WEEK...BRINGING A PERIOD OF UNSETTLED AFTERNOON AND
EVENING WEATHER. A BUILDING UPPER RIDGE WILL BRING HOT CONDITIONS
MID TO LATE WEEK. THE UPPER RIDGE WILL SHIFT WEST OVER THE WEEKEND
AND SHOULD TAKE SOME EDGE OFF THE HEAT...ALONG WITH AN INCREASING
CHANCE OF SHOWERS AND STORMS.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM MONDAY...UPPER RIDGE REMNANTS OVER THE AREA ALBEIT
FLATTENED BY PASSING SHORT-WAVE ENERGY...HAS ALLOWED POOR MIDDLE
LEVEL LAPSE RATES TO LINGER OVER THE WARNING AREA. A STRONG MCV
FEATURE WAS AIDING IN STRONG TO SEVERE CONVECTION OVER NE NC AND
SE VA. ANOTHER IMPULSE HEADING INTO WESTERN SC WAS SETTING OFF
SCATTERED TSTMS FROM FAR AUGUSTA GA TO COLUMBIA SC TO MARLBORO
COUNTY SC. STEERING FLOW WILL GUIDE CONVECTION FROM WSW TO ENE
AT 25 TO 30 MPH. SEVERAL OF THE NEAR TERM MODELS SUSTAIN THIS
ACTIVITY EASTWARD TOWARD THE COAST THROUGH LATE AFTERNOON AND
EARLY EVENING...WHERE AN AWAITING AND PARTIALLY PINNED SEA BRZ
COULD POTENTIALLY PULSE ECHO TOPS TO HIGHER REACHES...POSSIBLY
PRODUCING ISOLATED SEVERE STORMS ALONG OUR COASTAL INTERIOR IN
LATE AFTN THROUGH MID-EVENING.

TEPID OVERNIGHT TEMPERATURES MAY BARELY FALL BELOW 80 NEAR THE
COAST WITH MODERATE SW WINDS AND DEBRIS CLOUD COVER OVERNIGHT
AND ALSO THE ELEVATED MAXIMUMS WE SAW TODAY. HIGH MOISTURE
CONTENT WILL NOT ALLOW TEMPERATURES TO DROP IN RAPID FASHION.
MINIMUMS DAYBREAK TUESDAY ESSENTIALLY 77-80 NEAR THE COAST AND
MIDDLE 70S FARTHER INLAND. LOWS NEAR THE BEACHES 81-83 DEGREES.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...THE MID LEVEL PATTERN WILL REMAIN ACTIVE FOR ONE MORE
DAY OR TWO DEPENDING ON WHAT MODEL YOU PREFER. THE ZONAL FLOW AT THE
BASE OF A SUBTLE EAST COAST TROUGH WILL BE THE CULPRIT. THE GFS
SHOWS ANOTHER RESPECTABLE SHORTWAVE MOVING ACROSS TUESDAY AFTERNOON
AT MAX HEATING AS DOES THE NAM. I HAVE MAINTAINED THE ROBUST POPS
FOR THIS TIME. FOR WEDNESDAY...BOTH MODELS GENERATE PRECIPITATION
BUT THE GFS SEEMS TO BE MORE DERIVED FROM THE SEA BREEZE WHILE THE
NAM SHOWS YET ANOTHER SHORTWAVE. I INCREMENTALLY INCREASED POPS FOR
THIS TIME BASED ON THE IMPRESSIVE INSTABILITY AVAILABLE KNOWING IT
WONT TAKE MUCH OF A CATALYST FOR DEVELOPMENT. TEMPERATURE GUIDANCE
REMAINS CONSISTENT AND NO CHANGES WERE WARRANTED. READINGS WILL
REMAIN ABOUT A FULL CATEGORY ABOVE CLIMATOLOGY ACROSS THE BOARD.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
AS OF 3 PM MONDAY...THURSDAY WILL BRING ONE LAST DAY OF OPPRESSIVE
HEAT AND HUMIDITY. UPPER RIDGE WILL BE LOCATED OVER THE LOWER MS
VALLEY WITH NW FLOW LOCALLY. MODEL SOLUTIONS VARY REGARDING THE
STRENGTH OF THIS FLOW AND HOW MUCH SHORTWAVE ENERGY IS EMBEDDED
THEREIN, WHICH WILL MODIFY OUR PRECIP CHANCES. THE CMC ACTUALLY
LOOKS LIKE A GOOD COMPROMISE BETWEEN THE GFS AND THE ECMWF. THE
LATTER KEEPS ENERGY AND PRECIP CHANCES JUST NORTH OF HERE WHILE THE
GFS HAS LOWERING HEIGHTS IN A VORTICITY-LADEN FLOW. WILL PAINT
HIGHEST POPS OVER NRN ZONES BUT ALLOW FOR ISO COVERAGE JUST ABOUT
ANYWHERE DUE TO MESOSCALE PROCESSES AND/OR HEATING LEADING TO
PARCELS AUTO-CONVECTING TO THE LFC/LEVEL OF FREE CONVECTION.
THURSDAY NIGHT INTO FRIDAY MAY TURN ACTIVE AS DEEPENING TROUGINESS
OFF THE MID ATLANTIC COAST DRIVES A COLD FRONT INTO THE REGION. HOW
MUCH THIS UPPER TROUGH AMPLIFIES WILL AFFECT HOW UNSETTLED THE
WEEKEND STAYS. THE GFS AGAIN IS A RATHER STRONG OUTLIER WHEREAS THE
CMC AND ECWMF KEEP THE FRONT CLOSER ON SATURDAY FOR PERHAPS ANOTHER
ACTIVE DAY OF CONVECTION. SUNDAY INTO MONDAY SHOULD SEE THE FRONT
DRIVEN FAR ENOUGH SOUTH FOR LESS ACTIVE RADAR DAYS AND PERHAPS SOME
COOLER AND DRIER AIR.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
AS OF 18Z...STILL SOME CONVECTIVE INHIBITION TO OVERCOME THIS
AFTERNOON. CAPES APPROACHING 3000 J/KG ALONG THE COAST...HOWEVER
LFC`S STILL HOLDING AROUND 2000 METERS AND HIGHER. BELIEVE THE
AFTERNOON HEATING WILL FINALLY OVERCOME THE CIN...AND WE WILL SEE
SCATTERED CONVECTION FROM MID TO LATE AFTERNOON...DECREASING AROUND
03Z. WITH PRECIPITABLE WATER JUST UNDER TWO INCHES...HEAVY
DOWNPOURS ARE EXPECTED WITH A STORM MOTION AROUND 20 KTS.
CONVECTIVE DEBRIS CLOUDS OVERNIGHT...WITH SOME LIGHT FOG POSSIBLE.
CONTINUED SOUTHWEST FLOW ON TUESDAY WITH MORE SCATTERED CONVECTION
IN THE AFTERNOON.

EXTENDED OUTLOOK...CHC AFTERNOON/EVENING SHRA/TSRA THROUGH THE
PERIOD. SUB-VFR FOG AND/OR CEILINGS WILL BE POSSIBLE DURING THE
EARLY MORNING HOURS EACH DAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3 PM MONDAY...A BUMPY 3-4 FEET ON THE WATERS AND SW GUSTS
TO 20 KT SHOULD BE EXPECTED THROUGH DAWN ON TUESDAY. MARINERS MAY
CONSIDER A RADAR UPDATE BEFORE HEADING OUT AS TSTMS MAY BE OVER
PORTIONS OF THE WATERS AT ANY GIVEN MOMENT. STORM MOTION THROUGH
EARLY TUESDAY WSW TO ENE AT 25 TO 30 MPH. THE BULK OF WAVE ENERGY
WILL TIED TO LOCAL WINDS WITH SHORT PERIODS THUS MAINTAINING THE
BUMPY SEA-STATE. SEA SPECTRUM COMPOSED OF SSW WAVES 3-4 FEET AT
4-5 SECONDS AND WEAK SE SWELL OF 1 FOOT EVERY 9 SECONDS.

SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...ELONGATED TROUGH OF LOW PRESSURE WILL PREVAIL
ACROSS THE WATERS THROUGH THE PERIOD. THIS FEATURE WILL BE STRONGER
TUESDAY WITH SOUTHWEST WINDS OF 10-15 KNOTS AND 15-20 ACROSS THE
OUTER WATERS. FOR WEDNESDAY...SPEEDS DIMINISH MARKEDLY TO TEN KNOTS
OR LESS. THIS SEEMS A LITTLE TOO MUCH OF A DECREASE AND SUBSEQUENT
FORECASTS MAY WANT TO INCREASE THE SPEEDS. SWAN WAVE GUIDANCE SHOWS
3-5 FEET FOR SEAS TUESDAY ESPECIALLY LATER IN THE DAY AND 1-3 FEET
WEDNESDAY.

LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...THURSDAY`S SOUTHWESTERLY FLOW WILL BE VERY LIGHT
ON ACCOUNT OF A PIEDMONT TROUGH KEEPING THE GRADIENT FAIRLY RELAXED.
COLD FRONT MOVES THROUGH ON FRIDAY BRINGING CONSIDERABLE VEERING
ESPECIALLY OVER NRN ZONES WHILE WIND SPEEDS REMAIN VERY LIGHT. COLD
FRONT WILL BE SOUTH OF MOST IF NOT THE ENTIRE AREA BY SATURDAY
MEANING NORTHEASTERLY WINDS CAPPED AT 10 KTS...NO SURGE BEHIND THE
BOUNDARY MORE TYPICAL OF THE COOL SEASON. SEAS GENERALLY 2 TO AT
MOST 3 FT THROUGH THE PERIOD.

&&

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

&&

$$
SYNOPSIS...SHK
NEAR TERM...MJC
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...DL







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