936 FXUS62 KILM 192339 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 739 PM EDT MON MAY 19 2014 .SYNOPSIS... QUIET AND DRY CONDITIONS ARE ON TAP MUCH OF THIS WEEK AS HIGH PRESSURE MOVES OVER THE CAROLINAS AND INTO THE GULF STATES. A BUILDING UPPER RIDGE OF HIGH PRESSURE WILL BRING TEMPERATURES ABOVE NORMAL WEDNESDAY AND THURSDAY. A COLD FRONT DROPPING IN FROM THE NORTH FRIDAY MAY STALL OVER SOUTH CAROLINA THIS WEEKEND. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 730 PM MONDAY...EXPECT MOSTLY CLEAR SKIES FOR THE OVERNIGHT PERIOD AS FLAT CU FIELD EVAPORATES WITH THE SETTING SUN. NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS: SURFACE HIGH PRESSURE OVER THE VIRGINIAS THIS AFTERNOON WILL DROP SOUTH OVERHEAD OF OUR FORECAST AREA THIS EVENING. THIS WILL SET THE STAGE FOR SUBSTANTIAL AND FAST-PACED TEMPERATURE DROPS THROUGH LATE EVENING INTO EARLY MORNING OUR UNDER LIGHT WIND AND A MOSTLY CLEAR DOME. UPPER 40S OVER PORTIONS OF THE INTERIOR TO THE LOWER AND MIDDLE 50S NEAR THE COAST EXPECTED. HEIGHT RISES AND ASSOCIATED SUBSIDENCE ALOFT WILL PROVIDE A HOSTILE ENVIRONMENT FOR SURVIVING CIRRUS TO RACE OVERHEAD FROM THE NW TONIGHT...BUT A FEW WISPS AND TENDRILS CANNOT BE ENTIRELY RULED OUT. NEGLIGIBLE IMPACTS ON MINIMUM TEMPERATURES EXPECTED WITH TYPICAL DIURNAL COOLING AND MINS OCCURRING NEAR DAYBREAK MONDAY. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...WARMING TREND THROUGH MID WEEK WILL BRING TEMPS BACK UP INTO THE 80S AS MID TO UPPER RIDGE BUILDS UP FROM THE GULF COAST. AT THE SURFACE THE HIGH WILL BE OVERHEAD TUES MORNING WITH A COOL START TO THE DAY. INCREASING H5 HEIGHTS AND PLENTY OF MAY SUNSHINE WILL HELP TO BRING TEMPS BACK UP TOWARD NORMAL. THE HIGH SLIPS FARTHER SOUTH AND EAST TUES NIGHT THROUGH WED AS MID TO UPPER RIDGE HOLDS ON ALOFT. AS HIGH SLIPS SOUTH LEE SIDE TROUGHING WILL DEVELOP MAINLY NORTH OF AREA AS MINOR PERTURBATION RIDES OVER THE TOP OF THE RIDGE TUES AFTN. THIS WILL LEAD TO SOME CLOUDS REACHING OUR AREA WHILE ANY PCP REMAINS NORTH AS DRY AND SUBSIDENCE RULE. THE GRADIENT WILL BECOME PINCHED BY WED AFTN AS PIEDMONT TROUGH BECOMES MORE PRONOUNCED PRODUCING AN INCREASING RETURN FLOW WITH WAA. WITH A GREATER WESTERLY DOWNSLOPE COMPONENT TO THE FLOW ON WED AND WAA...EXPECT TEMPS TO REACH BACK UP ABOVE NORMAL. THE WESTERLY FLOW WILL ALSO KEEP SEA BREEZE PINNED CLOSER TO THE COAST. THEREFORE EXPECT MORE WIDESPREAD 80S TO NEAR 90 ON WED. THE RIDGE WILL GET SUPPRESSED FARTHER SOUTH THROUGH WED AND IT MAY BE FAR ENOUGH TO SOUTH TO ALLOW A MINOR PERTURBATION IN THE NW FLOW TO PRODUCE ANOTHER ROUND OF CLOUDS FOR WED NIGHT BUT AGAIN ANY PCP SHOULD HOLD OFF TO THE NORTH AND WEST. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM MONDAY...A HOT DAY TO BEGIN THE EXTENDED AS UPPER RIDGE MAINTAINS CONTROL LOCALLY FOR ONE MORE DAY BEFORE BECOMING SUPPRESSED TO THE SOUTH. 850MB TEMPS RISE TO 17-18C...WHICH COMBINED WITH DEEP NW FLOW (DOWNSLOPE COMPONENT)...AND AMPLE SUNSHINE...WILL ALLOW TEMPS TO SOAR TO 90+ EVERYWHERE AWAY FROM THE BEACHES. IT IS POSSIBLE THURSDAY WILL BE THE HOTTEST DAY OF 2014 SO FAR (92 ON MAY 8TH AT ILM, 94 AT FLO ON THE SAME DAY). EVEN THE BEACHES WILL LIKELY REACH INTO THE MID/UPR 80S AS THE SEA BREEZE GETS PINNED ON THE SHORE. CHANGES BEGIN THEREAFTER. LARGE RIDGE RESPONSIBLE FOR THE HEAT ON THURSDAY WILL BEGIN TO GET SHUNTED SOUTH TOWARDS THE MS VLY AS A DEEPENING TROUGH DRIFTS ACROSS THE NORTHEAST. THIS LEAVES THE REGION ENTRENCHED BETWEEN THESE TWO FEATURES...WITH MID LEVEL AND SURFACE FEATURES BECOMING SANDWICHED IN THE LOCAL VICINITY. AT THE SURFACE...A BACK DOOR TYPE COLD FRONT WILL DRIFT SOUTH ON FRIDAY AND THEN WAVER NEARBY INTO SUNDAY. THERE IS STILL QUITE A BIT OF UNCERTAINTY INTO THE SOUTHERN PROGRESSION OF THIS FEATURE. CLIMATOLOGY WOULD SUGGEST THE FRONT WILL STALL OVER THE ILM CWA...AND GUIDANCE TYPICALLY UNDER-DOES THE STRENGTH OF THE RIDGE WHICH WOULD SUPPORT A LACK OF SOUTHERN GAIN OF THE BOUNDARY. HOWEVER...GUIDANCE CONTINUES TO PUSH THE FRONT THROUGH FASTER AND STRONGER...AND THE LAST FRONT OF THIS TYPE ALSO MADE IT WELL SOUTH OF THE AREA. SO...WILL SHOW THE FRONT DROPPING THROUGH THE ENTIRE CWA BY SATURDAY MORNING...AND FRIDAY WILL FEATURE THE BEST CONVECTIVE CHANCES OF THE PERIOD. EVEN STRONGER NW FLOW ALOFT WITH RAPID DRYING WILL SUPPRESS MUCH OF ANY CONVECTIVE POTENTIAL SATURDAY...WITH ONLY SCHC SUNDAY DUE TO STEEP LAPSE RATES BENEATH THE MID-LEVEL TROUGH. TEMPS FRI-SUN WILL HOVER AROUND...TO SLIGHTLY BELOW...CLIMO. ADDITIONALLY...ALTHOUGH A LOT OF SUNSHINE IS EXPECTED DURING THIS PERIOD...PERIODIC BOUTS OF MCS-DEBRIS CLOUDINESS IN THE FORM OF MID/HIGH LEVEL AC/CI IS EXPECTED AS CONVECTIVE SYSTEMS DEVELOP WELL NW OF THE AREA AROUND THE RIDGE PERIPHERY. CURRENT GUIDANCE SUGGESTS MEMORIAL DAY WILL ALSO BE NICE...WITH TEMPS AROUND CLIMO ONCE AGAIN...BUT WITH DECREASED CONVECTIVE POTENTIAL AS MID-LEVEL RIDGING REDEVELOPS ACROSS THE SOUTHEAST. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 00Z...THIS TAF PERIOD SHOULD REMAIN QUIET WITH VFR CONDITIONS PREVAILING THROUGH 00Z WEDNESDAY. DIURNAL CU WILL DISSIPATE THIS EVENING WITH THE LOSS OF DAYTIME HEATING. HIGH PRESSURE OVER THE MID-ATLANTIC WILL BUILD SOUTHWARD OVERNIGHT...AND WINDS ACROSS THE CWA WILL BECOME LIGHT/VRB TO CALM. ALTHOUGH CONDITIONS WILL BE FAVORABLE FOR RADIATIONAL COOLING TONIGHT...DEWPOINTS IN THE 40S SHOULD LIMIT FOG DEVELOPMENT...THOUGH SOME TEMPO MVFR GROUND FOG BEFORE DAYBREAK IS NOT OUT OF THE QUESTION. VFR WILL PERSIST ON TUESDAY AS HIGH PRESSURE LIMITS US TO FEW/SCT MID-LEVEL CLOUDS. THE SFC HIGH WILL MOVE OFFSHORE IN THE AFTERNOON...WITH LIGHT/VRB WINDS BECOMING SOUTHWEST 5-8 KTS. ALONG THE COAST...SEA BREEZE PASSAGE WILL CREATE SOUTH WINDS AROUND 10 KTS THROUGH THE AFTERNOON HOURS. EXTENDED OUTLOOK...VFR WILL PREVAIL THROUGH THE EXTENDED PERIOD. SLIGHT CHANCE OF SHOWERS ON THURSDAY AND FRIDAY AS A COLD FRONT DROPS SOUTHWARD. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 730 PM MONDAY...WILL LIKELY DROP SCEC HEADLINES WITH THE NEXT ISSUANCE AS NEAR-SHORE WINDS ARE EXPECTED TO DROP SUBSTANTIALLY WITH THE SUNSET. NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS: ROUGHED UP WIND- SEAS PRESENTLY DUE TO STIFF ENE-E WINDS. WIND- SPEEDS WILL ABATE THIS EVENING BRINGING VASTLY IMPROVED CONDITIONS AS SURFACE HIGH PRESSURE SETTLES OVERHEAD OF THE WATERS TONIGHT. THE WIND- WAVE PORTION OF THE SEA- SPECTRUM WILL LIKEWISE EASE...LEAVING MAINLY E-ESE LONGER PERIOD WAVES ROLLING TO SHORE. 2-5 FOOT SEAS AND HIGHEST OFFSHORE EARLY EVENING...THEN 2-3 FEET BY DAYBREAK MONDAY UNDER AN IMPROVING TREND. NO TSTMS OR RESTRICTIONS TO VISIBILITY EXPECTED ON THE 0-20 NM WATERS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...HIGH PRESSURE RIDING OVERHEAD TUES MORNING WILL SHIFT FARTHER SOUTH LATE TUES INTO WED. THEREFORE LIGHT AND VARIABLE WINDS WILL BECOME SOUTH TO SOUTHWEST LATER TUE AS RETURN FLOW SETS UP. WINDS WILL INCREASE THROUGH WED INTO WED NIGHT AS PIEDMONT TROUGH BECOMES MORE PRONOUNCED AND CREATES A PINCHED GRADIENT. WNA SHOWS SEAS REACHING 5 FT IN THE OUTER WATERS WHILE SWAN PRODUCED SLIGHTLY HIGHER SEAS LATE WED INTO WED NIGHT. I CAPPED THE SEAS AT 5 FT AT THIS TIME. SOUTHWEST FLOW SHOULD PEAK AROUND 20 KT LATE WED AND WED NIGHT. OVERALL SEAS 2 TO 3 FT TUE BUILD TO 3 TO 5 FT WED AND WED NIGHT AS A RESULT OF INCREASING SOUTHWEST FLOW. WILL HEAD INTO PRECAUTIONARY CONDITIONS LATE WED BUT MAY REACH SCA FOR A FEW HOURS WED NIGHT. .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 300 PM MONDAY...HIGH PRESSURE STRETCHED ALONG THE GULF COAST WILL RIDGE TOWARDS THE WATERS THURSDAY...AHEAD OF A COLD FRONT DROPPING SOUTH TOWARDS THE AREA. THIS CREATES A PINCHED GRADIENT THURSDAY...WITH SW WINDS AROUND 15 KTS THROUGH THE DAY. OVERNIGHT THURSDAY INTO FRIDAY...THIS FRONT WILL DROP ACROSS THE WATERS...TURNING WINDS TO THE NORTH AT 10-15 KTS BY FRIDAY MORNING. THIS BOUNDARY WILL THEN WAVER IN THE VICINITY...CAUSING LIGHT AND VARIABLE WINDS MOST OF FRIDAY INTO SATURDAY...BEFORE A RENEWED PUSH OF NW WINDS DRIVES THE BOUNDARY TO THE SOUTH LATE IN THE PERIOD. HIGHEST SEAS WILL BE THURSDAY WITH 2-4 FT WAVE HEIGHTS EXPECTED. SEAS DROP FRIDAY AND SATURDAY ON THE LIGHTER WINDS...BECOMING 1-3 FT FRIDAY...AND EVEN LOWER ON SATURDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...RGZ NEAR TERM...MJC/REK SHORT TERM...RGZ LONG TERM...JDW AVIATION...BJR MARINE...MJC/REK/JDW/RGZ