160 FXUS62 KMHX 281934 AFDMHX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEWPORT/MOREHEAD CITY NC 334 PM EDT FRI SEP 28 2012 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT THEN WILL SLOWLY MOVE THROUGH THE REGION SATURDAY AND SATURDAY NIGHT BEFORE STALLING JUST OFF OF THE COAST SUNDAY. DEVELOPING LOW PRESSURE WILL MOVE NORTH OUT OF THE GULF MONDAY AND PUSH THE STALLED FRONT NORTH THROUGH THE AREA AS A WARM FRONT. THE LOW WILL MOVE INTO VIRGINIA WEDNESDAY AND PUSH A COLD FRONT INTO THE AREA. THIS FRONT WILL STALL ALONG THE COAST THURSDAY AND FRIDAY. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 330 PM FRIDAY...THE MODELS ARE IN FAIRLY GOOD AGREEMENT FOR THE FORECAST TONIGHT. STRONG CONVECTION DEVELOPING TO THE WEST ASSOCIATED WITH A MID LEVEL SHORTWAVE SHOULD WEAKEN AS IT MOVES TOWARD THE COASTAL PLAIN THIS EVENING DUE TO LOSS OF HEATING AND MOVEMENT INTO MORE STABLE AIR. BEST THREAT WILL BE ACROSS THE EXTREME NORTHWEST AND NORTH. THEN WILL INCREASE POPS AREA WIDE LATE TONIGHT AS A WEAK COLD FRONT SLOWLY MOVES INTO THE AREA. THINKING THERE SHOULD BE ENOUGH CLOUDS AROUND TO LIMIT RADIATIONAL COOLING AND THUS DENSE FOG POTENTIAL. THE COMBINATION OF CLOUDS AND LOW LEVEL SOUTHERLY FLOW WILL PRODUCE MILD LOWS IN THE MIDDLE 60S INLAND AND UPPER 60S/LOWER 70S ALONG THE COAST. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/... AS OF 330 PM FRIDAY...THE UPPER TROUGH AMPLIFIES SATURDAY AS AN UPPER LOW DROPS DOWN INTO THE LOWER GREAT LAKES. THE UPPER TROUGH WILL PRODUCE ENOUGH MOMENTUM TO PUSH THE COLD FRONT INTO SOUTHERN PORTIONS OF THE AREA LATE WHERE IT MAY BRIEFLY STALL AS WEAK AREAS OF LOW PRESSURE RIPPLE ALONG IT. TRENDED MORE TOWARD THE GFS AND WILL LIMIT POPS TO 50% FOR NOW AND INDICATE SCATTERED SHOWERS AND THUNDERSTORMS. EXPECT MOST PLACES WILL SEE SOME PRECIPITATION BUT NOT EXPECTING AN ALL DAY RAIN AT ANY 1 LOCATION. WILL FORECAST HIGHS CLOSER TO THE GFS/UPPER 70S/ AS THERE SHOULD BE SOME FILTERED SUNSHINE. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... AS OF 100 PM FRI...FRONT WILL SLOWLY CROSS THE FORECAST AREA EARLY SUNDAY MORNING. MODELS IN GOOD AGREEMENT ON TIMING OF THIS FEATURE. WAVE WILL FORM ON THE FRONT OVER THE GULF OF MEXICO MONDAY...AND MODELS DISAGREE ON TIMING OF THE LOW. UPPER LEVEL SOUTHWEST FLOW OVER THE SOUTHEAST WILL KEEP THIS MOVING ALONG. PRESENCE OF FRONT WEST OF THE AREA AND UPPER LEVEL ENERGY SWING AROUND UPPER LEVEL LOW NORTH OF THE GREAT LAKES WILL COMBINE TO KEEP THE PERIOD UNSETTLED WITH A CHANCE OF SHOWERS. INSTABILITY WILL BE MARGINAL...EXPECTING ONLY ISOLATED THUNDER. MODELS DO START TO DIVERGE NEAR THE BEGINNING OF THE WORK WEEK...WILL LEAN AWAY FROM THE GFS. MODELS IN DECENT AGREEMENT FOR THE START OF THE EXTENDED PERIOD. HIGH PRESSURE IN THE UPPER ATMOSPHERE OVER THE SOUTHEAST WITH A STRONG LOW PRESSURE TROUGH OVER THE MIDWEST MOVING TOWARD THE EAST ON TUESDAY. THERE ARE SOME DIFFERENCES IN THE SURFACE FEATURES WITH THE GFS LIFTING SURFACE LOW FASTER THAN ECMWF. THIS WILL HAVE ONLY SLIGHT EFFECT ON SENSIBLE WEATHER OVER EASTERN NC. DIFFERENCES MORE EVIDENT IN MODELS BY THE END OF THE WORKWEEK WITH GFS EXTENDING A COLD FRONT THROUGH EASTERN NC AND ECMWF TRYING TO BUILD HIGH PRESSURE OVER THE SOUTHEAST. EITHER WAY...THE PERIOD WILL BE UNSETTLED WITH CHANCE OF PRECIP THROUGH THE WEEK. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... SHORT TERM /THROUGH 18Z SATURDAY/... AS OF 130 PM FRIDAY...TWO CONCERNS TONIGHT: PRECIPITATION COVERAGE/INTENSITY AHEAD OF AN ADVANCING COLD FRONT AND POTENTIAL FOR IFR CONDITIONS IN FOG. EXPECTING SCATTERED SHOWERS/ISOLATED THUNDERSTORMS TO DEVELOP AHEAD OF FRONT LATE THIS EVENING OVER THE COASTAL PLAIN SPREADING TOWARD THE COAST LATE. EXPECTING AROUND 40-50% COVERAGE SO WILL HANDLE WITH A SHOWER VICINITY GROUP FOR NOW. AS FOR FOG IT APPEARS THAT WINDS WILL DECOUPLE BUT THERE SHOULD BE MID AND HIGH LEVEL CLOUDS ASSOCIATED WITH A MID LEVEL SHORTWAVE AHEAD OF THE FRONT SO THINKING THAT THIS WILL LIMIT THE DENSE FOG POTENTIAL AND WILL FORECAST PREVAILING MVFR CONDITIONS AFTER 06Z. ON SATURDAY THE FRONT WILL STALL OVER EASTERN NC AND SERVE AS A FOCUS FOR SCATTERED SHOWERS AND THUNDERSTORMS WITH THE POTENTIAL FOR MVFR TO BRIEF IFR CONDITIONS AT TIMES. LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 105 PM FRI...UPPER LEVEL LOW PRESSURE AND ASSOCIATED SURFACE FRONT AND LOW PRESSURE OVER THE SOUTHEAST WILL COMBINE TO KEEP THE WEATHER UNSETTLED THROUGH THE PERIOD. MAINLY VFR CONDITIONS THROUGH THE PERIOD...EXCEPT IN SCATTERED SHOWERS WITH MVFR CONDITIONS. MAY HAVE ISOLATED IFR CIGS IN HEAVIER SHOWERS...BUT THESE WILL BE VERY ISOLATED. && .MARINE... SHORT TERM /THROUGH SATURDAY/... AS OF 330 PM FRIDAY...EXPECT SOUTHWEST TO WEST FLOW 10-15 KT AHEAD OF THE APPROACHING COLD FRONT TONIGHT WITH SEAS CONTINUING AT 1-3 FT. WINDS ARE FORECAST TO SHIFT TO THE NORTHWEST AND NORTH 15 KT OR LESS LATE TONIGHT ACROSS THE NORTHERN WATERS AND ALBEMARLE SOUND AS THE FRONT MOVES SLOWLY SOUTHEAST. WINDS WILL THEN SHIFT TO THE NORTHWEST TO NORTH OVER THE CENTRAL WATERS SATURDAY NORTH OF CAPE LOOKOUT SATURDAY 15 KT OR LESS AS THE FRONT CONTINUES TO MOVE SLOWLY SOUTHEAST. THE FRONT IS FORECAST TO BRIEFLY STALL OVER OR JUST SOUTH OF THE SOUTHERN WATERS LATE SATURDAY WITH WINDS REMAINING 15 KT OR LESS. WAVES ARE FORECAST TO CONTINUE 1-3 FT SATURDAY. LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 113 PM FRI...STRONG UPPER LEVEL LOW OVER THE GREAT LAKES REGION THROUGH THE PERIOD WILL HELP KEEP THINGS UNSETTLED THROUGH MID WEEK. QUASI STATIONARY FRONT OVER THE SOUTHEAST THROUGH THE PERIOD. GRADIENT ASSOCIATED WITH THE FRONT WILL BE LOOSE...SO WINDS WILL REMAIN BELOW SCA CRITERIA. SOME MODEL DIFFERENCES ON PLACEMENT OF SURFACE FEATURES...WILL LEAN AWAY FROM THE GFS. EXPECTING A FRONT TO CROSS THE WATERS EARLY SUNDAY MORNING WITH WIND BECOMING SOUTHWEST AGAIN SUNDAY EVENING. FORECAST SPEED AND DIRECTION WILL BE DEPENDENT ON SURFACE FEATURE PLACEMENT...AND CONFIDENCE IS FAIRLY LOW. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JME NEAR TERM...JME SHORT TERM...JME LONG TERM...CGG AVIATION...CGG/JME MARINE...CGG/JME