FXUS61 KOKX 200143 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE UPTON NY 943 PM EDT SAT JUL 19 2008 .SYNOPSIS... HIGH PRESSURE WILL REMAIN ENTRENCHED OVER THE MID ATLANTIC...WHILE A WEAK COLD FRONT SAGS SOUTH TOWARD SOUTHERN NEW ENGLAND AND THE LOWER HUDSON VALLEY. THE HIGH WILL DRIFT FARTHER OFFSHORE TONIGHT AND SUNDAY...ALLOWING A SLOW MOVING COLD FRONT TO APPROACH SUNDAY AND MONDAY. THE FRONT WILL PUSH JUST EAST OF THE AREA MONDAY NIGHT...THEN REMAIN NEARBY UNTIL THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... LATEST RADAR IMG CONTINUES TO SHOW ALL SHOWERS AND TSTMS WELL NORTH OF THE CWA. WILL GO AHEAD AND DROP POPS ACROSS THE CWA BY 10%...KEEPING SLIGHT CHANCE ACROSS THE NORTHERN ZONES. A WEAK SHORT WAVE WILL PASS N OF THE AREA...CAUSING A WEAK COLD FRONT TO SAG SE TOWARD THE REGION. THIS FRONT WILL STALL AND INCREASE CLOUD COVER AND MOISTURE ACROSS THE REGION THROUGH THIS EVENING. DURING THE OVERNIGHT...A SHORT WAVE MOVING E OF THE GREAT LAKES WILL WEAKEN ADDING CONVECTIVE CLOUD DEBRIS TO OUR AREA. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/... A STRONGER SHORT WAVE WILL APPROACH THE REGION LATER SUNDAY. WILL THIS WAVE BE DEEP ENOUGH TO CATCH TROPICAL STORM CRISTOBAL AND GUIDE IT SAFELY OUT TO SEA? THE GFS SUGGESTS IT MIGHT. THE NAM SUGGESTS A WEAKER WAVE PASSING FURTHER N WHICH DOES NOT CATCH THE DEVELOPING TROPICAL STORM. STAY TUNED ON THE LATEST DEVELOPMENTS ON CRISTOBAL. IMPACTS FROM CRISTOBAL AT THE MINIMUM WILL BE A MODERATE TO HIGH RISK OF RIP CURRENTS. IF MOISTURE WORKS FAR ENOUGH N AND PHASES IN WITH A STRONGER APPROACHING SHORT WAVE...A HEAVY RAINFALL COULD ALSO RESULT ACROSS MOST OF THE AREA. AT THIS POINT...TIMES ARE WAY TOO EARLY TO MENTION BASED ON FCST TRACK UNCERTAINTY. STAY TUNED. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... COMPARED TO ECMWF AND THE ENSEMBLES GFS IS TOO PROGRESSIVE IN EXITING TROUGH OUT OF THE EASTERN US TOWARDS THE END OF NEXT WEEK...SO LEANED TOWARDS AN ECWMF/GEFS ENSEMBLE MEAN BLEND (WHERE SIGNIFICANT DIFFERENCES BETWEEN THOSE LEANED TOWARDS ECMWF) FOR THE EXTENDED. BASICALLY EXPECT QUASI-STATIONARY FRONT WILL BE IN THE GENERAL VICINITY (MORE THAN LIKELY TOWARDS THE EASTERN PART IF NOT JUST EAST OF THE CWA) THROUGH THE PERIOD...WITH PERIODIC WAVES OF LOW PRESSURE RIDING EAST ALONG IT. RESULT IS BASICALLY RUN CHANCE/SLIGHT CHANCE POPS FOR SHOWERS AND THUNDERSTORMS THROUGH THE PERIOD BASED ON BEST ESTIMATE OF WHEN WAVES WILL WORK CLOSE TO THE AREA. HIGH TEMPERATURES ARE FORECAST TO RUN AROUND NORMAL (ON THE COOL SIDE OF THE BOUNDARY)...WITH LOWS NEAR TO A FEW DEGREES ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION /02Z SUNDAY THROUGH THURSDAY/... MOST TSTM ACTIVITY HAS ENDED ACROSS THE CWA. WILL CONTINUE TO MONITOR TSTMS ACROSS THE NORTHERN TIER...BUT AT THIS RATE...ONLY KSWF AND MAYBE KHPN WOULD BE AFFECTED. MOSTLY VFR THROUGH TONIGHT...HOWEVER BASED ON PERSISTENCE...HAVE A TEMPO PERIOD LATE AT NIGHT/EARLY SUNDAY MORNING FOR MVFR VSBYS IN HAZE FOR THE CITY TERMINALS. FOR THE OTHER TERMINALS...HAVE A PREVAILING PERIOD OF MVFR VSBYS GENERALLY AFTER MIDNIGHT...WITH A COUPLE TERMINALS DROPPING TO IFR FOR A PERIOD. AGAIN...THIS IS BASED MAINLY ON PERSISTENCE. WINDS GENERALLY SW THROUGH THE PERIOD...EXCEPT MORE TOWARDS THE S FOR KJFK AND PERHAPS KISP THROUGH EARLY THIS EVENING. OUTLOOK FOR 00Z MONDAY THROUGH WEDNESDAY... CONVECTION SUNDAY AFTERNOON THROUGH MONDAY MAY BRING SUB-VFR CONDITIONS. OUTSIDE OF THIS...VSBYS MAY LOWER IN HZ/BR SUNDAY NIGHT MAINLY AWAY FROM THE CITY TERMINALS. THERE IS A SOMEWHAT LOWER CHANCE OF CONVECTION ON TUESDAY AND WEDNESDAY...BUT SUB-VFR CONDITIONS WILL STILL BE POSSIBLE IN AREAS AFFECTED BY IT. && .MARINE... A MODERATE RISK OF RIP CURRENTS WILL CONT AS AN E SWELL FROM BERTHA CONTS. A S SWELL IS FCST TO DEVELOP DURING SUNDAY AS TROPICAL STORM CRISTOBAL MOVES NE. WILL MAINTAIN SCA FOR ANZ350 AS ON ONSHORE FLOW OF AROUND 15 KT COUPLED WITH LINGERING SWELL FROM BERTHA SHOULD BE ABLE TO BUILD WAVES TO 5 FT AT TIMES DURING THE NIGHT. WINDS SUBSIDE A BIT OVERNIGHT INTO TOMORROW MORNING...AND SWELL FROM BERTHA WILL CONTINUE TO DIMINISH...SO DO NOT HAVE CONFIDENCE TO CARRY SCA HERE INTO TOMORROW MORNING. ALL OTHER ZONES EXPECTED TO REMAIN SUB SCA THROUGH THE NIGHT WITH A GENERAL SW FLOW OF 15 KT OR LESS. S TO SW WINDS PICK UP AGAIN TOMORROW AFTERNOON...AND SEAS POSSIBLY REACH 5 FT BY THE END OF THE AFTERNOON ON THE OCEAN. WITH LOW CONFIDENCE IN ITS OCCURRENCE ATTM...AND IT BEING LATE IN THE PERIOD...WILL NOT HOIST ANY OTHER FLAGS. SOMEWHAT BETTER CHANCE FOR SCA SEAS SUNDAY NIGHT AS COLD FRONT FROM THE NORTH MOVES CLOSER TO THE WATERS...BUT 5 FT SEAS MORE LIKELY TO OCCUR ON MONDAY WITH TIGHTENING PRESSURE GRADIENT/FROPA...AS WELL AS A BUILDING SE SWELL FROM CRISTOBAL. WITH VERY WEAK PRESSURE GRADIENT FORECAST OVER THE WATERS TUESDAY NIGHT THROUGH THURSDAY...EXPECT WINDS AOB 15 KT (MAINLY AOB 10 KT WITH SOME AFTERNOON SEA BREEZE ENHANCEMENT)...SO EXPECT SEA BELOW SCA LEVELS AS WELL. && .HYDROLOGY... SCATTERED TSTMS COULD PRODUCE A QUICK LOCALIZED 1/2 INCH OF RAIN OVER INTERIOR SECTIONS THROUGH MIDNIGHT. THERE IS A POTENTIAL FOR PERIODIC CONVECTIVE RAINFALL THRU THE PERIOD WITH LOW LVL MOISTURE INCREASING. THERE IS A POTENTIAL FOR HEAVY RAINFALL STARTING LATE SUNDAY INTO MONDAY... ESPECIALLY NORTH AND WEST OF NYC. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 AM EDT SUNDAY FOR ANZ350. && $$ SYNOPSIS...GC NEAR TERM...MPS SHORT TERM...GC LONG TERM...PFM AVIATION...MPS MARINE...JC/PFM HYDROLOGY...GC