747 FXUS62 KILM 081912 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 312 PM EDT SUN JUN 8 2014 .SYNOPSIS... WEAK HIGH PRESSURE OFF THE NORTH CAROLINA COAST WILL STRENGTHEN OFFSHORE...WITH SOUTH WINDS BRINGING WARM...HUMID CONDITIONS AND A RISK FOR SCATTERED THUNDERSTORMS ALMOST EVERY DAY THIS WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 130 PM SUNDAY...NEAR TERM CHALLENGE REMAINS CENTERED AROUND THE CONVECTION DEVELOPING BASICALLY IN THE SAME PLACE AS IT DID YESTERDAY ALBEIT WITH A BIT OF A MORE NORTHWARD EXTENSION. SOME OF THE STRONGER CELLS ARE TAKING ON A BIT OF MORE NORTH TO EVEN NORTHWESTWARD MOVEMENT TOWARD THE BETTER INSTABILITY AXIS. OVERALL THE AREA IS MOVING SLOWLY TO THE EAST. THE MODELS KEEP THE ACTIVITY BASICALLY CONFINED TO THE WESTERN COUNTIES. WILL HOLD ON TO THE POPS THERE AND POSSIBLY INTRODUCE HIGHER CHANCE TO LIKELY VALUES IN THE NEXT FEW HOURS BASED ON TRENDS. COAST SHOULD REMAIN ALL BUT CONVECTION FREE. OVERNIGHT...CONVECTION QUICKLY DISSIPATES WITH THE LOSS OF DAYTIME HEATING. FOG MAY BECOME A CONCERN INLAND DEPENDING ON THE EXTENT OF RAINFALL. FINALLY OVERNIGHT LOWS SHOULD ONCE AGAIN DROP INTO THE 60S AREA WIDE. A DEGREE OR TWO ABOVE THIS MORNINGS VALUES. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...A WEAKENING COLD FRONT/TROUGH LINE WILL ESSENTIALLY DISSIPATE ACROSS THE CENTRAL CAROLINAS MONDAY AS A PAIR OF SHORTWAVES LIFT NORTH OVER A BUILDING WESTERN ATLANTIC RIDGE. SURFACE PRESSURES WILL RISE IN ASSOCIATION WITH THIS STRENGTHENING BERMUDA HIGH. THERE WILL BE AN INCREASE IN HEAT AND HUMIDITY EXPECTED OVER THE CAROLINAS AS SOUTH WINDS BRING TROPICAL AIR IN FROM FLORIDA AND THE BAHAMAS. DRY AIR ALOFT WILL ACT TO LIMIT ALREADY-SMALL CHANCES OF DIURNAL CONVECTION. TODAY'S 12Z MODEL GUIDANCE PAINTS A PATCHWORK OF QPF OVER THE NEXT FEW DAYS...BUT WITHOUT ANY UPPER LEVEL FEATURES OF NOTE AND LITTLE INTER-MODEL CONSISTENCY IT IS TOUGH TO USE THIS TO BASE A FORECAST ON. THEREFORE I WILL FOCUS T-STORM CHANCES ON THE AFTERNOON SEABREEZE BOUNDARY AND TYPICAL DIURNAL INSTABILITY TRENDS...WITH POPS NO HIGHER THAN 30 PERCENT ANYWHERE OVER THE NEXT TWO DAYS. I WOULD HAVE LOWER POPS IN THE FORECAST EXCEPT FOR THE FACT GFS/NAM STORM-MOTION VECTORS ARE 12-18 MPH BOTH DAYS...MEANING EVEN A FEW STORM CELLS COULD COVER A GOOD DEAL OF TERRITORY. HIGHS MONDAY SHOULD EXCEED 90 DEGREES FOR MOST AREAS MORE THAN 15 MILES INLAND. MID TO UPPER 80S ARE EXPECTED CLOSER TO THE BEACHES. 850 MB TEMPS AROUND +17C ON MONDAY WILL INCREASE ANOTHER DEGREE (OR TWO) ON TUESDAY RESULTING IN WIDESPREAD 92-95 DEGREE TEMPS INLAND. ADD IN DEWPOINTS OF 70+ DEGREES AND HEAT INDICES TUESDAY COULD APPROACH 100 DEGREES IN SPOTS. OVERNIGHT LOWS SHOULD ONLY FALL INTO THE 70-75 RANGE BOTH NIGHTS. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 300 PM SUNDAY...FAIRLY WELL PRONOUNCED UPPER TROUGH TO OUR WEST ESPECIALLY FOR JUNE...WITH A LEAD SHORTWAVE CROSSING THE REGION AHEAD OF THE MAIN TROUGH ON WEDNESDAY. THIS SHORTWAVE SHOULD PROBABLY CALL FOR SLIGHTLY HIGHER THAN CLIMO POPS...WILL GO AROUND 40. SOME ADDED CLOUD COVER WILL ALSO TAKE THE EDGE OFF OF TUESDAY'S HEAT BUT MAY STILL BE A FEW DEG ABV CLIMO. MODELS AT ODDS AS TO WHEN THE MAIN VORT AXIS SWINGS ACROSS WITH SOLUTIONS VARYING FROM THURSDAY TO FRIDAY. IN THE END IT SEEMS BEST TO CARRY SIMILAR/40-ISH POPS THROUGH FRIDAY. A WEAKENING BACKDOOR-ISH COLD FRONT DROPS INTO THE AREA ON SATURDAY AND IT MAY LAST INTO SUNDAY. TOUGH TO CUT DIAMONDS AND SAY WHERE EXACTLY IT STALLS EITHER DAY. CURRENT GFS FOR EXAMPLE HAS IT FAR ENOUGH SOUTH ESP BY SUNDAY THAT SOME DRIER WEATHER CAN BE FCST FOR NC ZONES. GIVEN THE STRENGTH OF THE UPPER RIDGE AND THE FACT THAT FRONTS DON'T GET QUITE AS FAR SOUTH AS PROGGED THIS TIME OF YEAR PREFER TO KEEP SCATTERED POPS EVERYWHERE OVER THE WEEKEND WHILE SHOWING A SLIGHT TRIMMING OF HIGH TEMPS. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AS OF 18Z...VFR EXPECTED THIS AFTERNOON. WINDS WILL BE SE AROUND 10 KNOTS WITH ISOLATED GUSTS TO AROUND 20 KTS AT THE COASTAL TERMINALS. THERE IS AN INCREASING CHANCE THAT CONVECTION TO THE SW-W OF KFLO/KLBT WILL MOVE INTO THE KFLO/KLBT TERMINALS THIS AFTERNOON. BUT SINCE THE AIRMASS IS STILL QUITE STABLE WILL JUST INDICATE VCSH ATTM AND NO TSRA IN TAFS. NO PRECIPITATION IS EXPECTED AT THE COASTAL TERMINALS. SE-S WINDS WILL GRADUALLY DECREASE THIS EVENING. EXPECT A LIGHT S-SW WIND TO CONTINUE OVERNIGHT...EXCEPT LGT/VRBL AT KFLO/KLBT. LOW VFR CIGS EXPECTED TO DEVELOP IN THE PRE-DAWN HOURS. VSBYS COULD DROP TO TEMPO MVFR IN BR AT KFLO/KLBT. CLOUD COVER SHOULD HELP LOWER ANY POTENTIAL FOR ANY IFR VSBYS. AFTER SUNRISE VFR EXPECTED WITH S-SW WINDS. EXTENDED OUTLOOK...GENERALLY VFR. CHANCE OF MAINLY AFTN/EVNG SHRA/TSRA WITH TEMPO SUB-VFR FLIGHT CONDITIONS THROUGH THE PERIOD. SLIGHT CHANCE OF MVFR VSBYS IN FG EARLY EACH MORNING MAINLY AT THE INLAND TERMINALS. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 130 PM SUNDAY...EAST TO SOUTHEAST FLOW WILL CONTINUE THIS AFTERNOON ON THE ORDER OF 10-15 KNOTS. THE FLOW WILL BECOME MORE SOUTHERLY OVERNIGHT AS THE SEA BREEZE AFFECTS WANE. SPEEDS WILL ALSO DROP TO AROUND TEN KNOTS. SIGNIFICANT SEAS WILL BE 2-3 FEET. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...BERMUDA HIGH PRESSURE WILL EXPAND ACROSS THE WESTERN ATLANTIC THE FIRST HALF OF THIS WEEK. RISING PRESSURES OFFSHORE AND A STALLED FRONT FROM TENNESSEE ACROSS THE CENTRAL APPALACHIANS MEANS OUR WIND DIRECTIONS WILL BE PRIMARILY SOUTH- SOUTHWEST THROUGH TUESDAY NIGHT. SHOWER AND THUNDERSTORM CHANCES APPEAR QUITE LOW...ALTHOUGH MODELS SEEM TO BE FOCUSING ON TUESDAY MORNING FOR A LITTLE BETTER POTENTIAL ACROSS THE NORTH CAROLINA COASTAL WATERS. OTHERWISE WITH WINDS AVERAGING 10 KNOTS (LOCALLY 15 KNOTS WITH THE AFTERNOON SEABREEZE) SEAS SHOULD RUN 2-3 FEET. LONG TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 300 PM SUNDAY...PRETTY STATIC WIND AND WAVE CONDITIONS THROUGH THE PERIOD DESPITE A LITTLE MORE ACTIVITY IN THE FLOW ALOFT THAN WHAT ONE WOULD EXPECT FOR JUNE. WEST ATLANTIC HIGH PRESSURE IN CONTROL ON WEDNESDAY THOUGH AN EARLY DAY RIDGE AXIS INTO THE CAROLINAS MAY CAST A LITTLE VARIABILITY IN THE OTHERWISE S TO SW FLOW. WEAK OVERLAND TROUGH ASSOC WITH UPPER LEVEL IMPULSE ON THURSDAY TO TIGHTEN THE GRADIENT TO THE TUNE OF JUST A FEW KNOTS WORTH OF WIND. THIS FEATURE MAY PERSIST INTO FRIDAY...IF SO THEN THERE MAY BE A MARGINAL INCREASE IN SWRLY SWELL ENERGY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...TRA NEAR TERM...SHK SHORT TERM...TRA LONG TERM...MBB AVIATION...SHK/MRR