AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 259 PM EDT MON APR 18 2011 .SYNOPSIS... A STATIONARY FRONT JUST SOUTH OF THE REGION THE NEXT TWO DAYS WILL MOVE NORTH OF THE AREA AS A WARM FRONT EARLY WEDNESDAY AS LOW PRESSURE MOVES INTO EASTERN CANADA. THAT LOW/S COLD FRONT WILL PASS ACROSS THE AREA WEDNESDAY NIGHT FOLLOWED BY HIGH PRESSURE TO END THE WEEK. ANOTHER WARM AND COLD FRONT ARE EXPECTED TO AFFECT THE REGION ON SATURDAY WITH HIGH PRESSURE RETURNING FOR SUNDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... FCST REMAINS ON TRACK THIS AFTN. SHORTWAVE OVER WRN PA APPROACHING THE AREA...WITH RADAR ECHOES APPROACHING THE CWA BUT NO PCPN REPORTED UPSTREAM. IT APPEARS THAT THE DRY LOW LEVELS WILL INHIBIT THE DEVELOPMENT OF RAIN. LOW CHANCES THEREFORE REMAIN IN THE FCST FOR TODAY. UPPER LEVEL VORT/CLOSED LOW SEEN OVER THE MARITIMES IS LIFTING OUT QUICKLY LEAVING A ZONAL PATTERN OVER THE EASTERN U.S. FRONT STALLS JUST SOUTH OF THE REGION THIS MORNING AND WEAKENS. WEAK WESTERLY FLOW AT SFC THIS MORNING BACKS TO SOUTHERLY THIS AFTN. PSEUDO SEA BREEZE ENHANCES FLOW AT COAST WITH AFFECT ON TEMPS. CONDITIONS SHOULD REMAIN MOSTLY DRY WITH MODEST 1000-500 MB RELATIVE HUMIDITIES...HOWEVER AN ISOLATED SHOWER OR SPRINKLE IS POSSIBLE LATE IN THE DAY NORTH AND WEST OF NYC...WHERE THERE WILL BE MORE MOISTURE TO LIFT OVER THE WARM FRONT...AND THICKNESS GRADIENTS WILL BE TIGHTER. TEMPERATURES WILL BE SEASONABLE...MAXING OUT IN THE UPPER 50S TO LOWER 60S IN MOST SPOTS. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... AFOREMENTIONED TIGHT THICKNESS GRADIENT SLOWLY PUSHES EAST THROUGH THE CWA MONDAY NIGHT...AS WEAK OVERRUNNING FLOW LEADS TO ANOTHER CHANCE OF SHOWERS...MAINLY OVER NORTHERN AREAS. WINDS AT THE SURFACE WILL BE LIGHT AND VARIABLE WITH A WEAK STATIONARY FRONT IN PLACE. A BETTER CHANCE OF RAIN ARRIVES FOR TUESDAY...IN ASSOCIATION WITH A WEAK MID-LEVEL SHORTWAVE AND WARM AIR ADVECTION. KEPT THUNDER OUT OF FORECAST AS MID-LEVEL LAPSE RATES AND LIFTED INDICES ARE NOT CONDUCIVE. LIGHT EASTERLY WINDS WILL KEEP TEMPS IN THE 50S. A MORE POTENT SHORTWAVE ADVANCES FROM THE GREAT LAKES ON WEDNESDAY. MODELS DIVERGE ON THE STRENGTH OF THIS TROUGH...AS WELL AS THE ASSOCIATED SURFACE LOWS. THE DETAILS ASIDE...THERE WILL BE A CHANCE OF RAIN WEDNESDAY INTO WEDNESDAY NIGHT IN DUE TO DECENT WARM AIR ADVECTION AHEAD OF THE APPROACHING SHORTWAVE TROUGH AND COLD FRONT. DEPENDING ON THE TIMING OF THE COLD FROPA...CONVECTION IS ALSO POSSIBLE. && .LONG TERM /THURSDAY THROUGH SUNDAY/... A DEPARTING COLD FRONT CONTINUES TO TREK EASTWARD ON THURSDAY AS HIGH PRESSURE BUILDS IN AT THE SURFACE. THIS HIGH GRADUALLY BUILDS OVERHEAD BY FRIDAY MORNING AND MOVES EAST OF THE AREA FRIDAY AFTERNOON. EXPECT DRY WEATHER THROUGH THIS TIME PERIOD. ANOTHER PAC STORM SYSTEM IS FORECAST TO TRACK NORTHEAST ACROSS THE GREAT LAKES NEXT WEEKEND...FIRST IMPACTING THE AREA WITH OVERRUNNING RAIN FRIDAY NIGHT INTO SATURDAY. ADDITIONAL RAIN...WITH POSSIBLE CONVECTION...WILL BE POSSIBLE SATURDAY NIGHT WITH THE PASSAGE OF A COLD FRONT. UNSETTLED WEATHER MAY CONTINUE INTO MONDAY WITH THE APPROACH OF ANOTHER LOW PRESSURE SYSTEM. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... WEAK HIGH PRESSURE ACROSS THE AREA THIS AFTN. A FRONTAL BOUNDARY JUST SOUTH OF THE AREA WILL BECOME STATIONARY TONIGHT AS A WEAK WAVE OF LOW PRESSURE APPROACHES FROM THE WEST. VFR THROUGH 06Z...THEN PATCHES OF MVFR IN BR THROUGH 12Z. CHANCES FOR SHOWERS ARE DECREASING AND LOOK TO REMAIN CONFINED TO JUST KSWF. TRICKY WINDS EARLY THIS AFTN. FINALLY SHOWING SIGNS OF BACKING TO THE SOUTH...BUT GUSTS HAVE NOT COMPLETELY SUBSIDED AT NYC TERMINALS AS EXPECTED. THICKER CLOUD OVER MOVING IN SHOULD LIMIT MIXING BUT GUSTS UP TO 20 KT STILL POSSIBLE THROUGH 20Z OR SO. UNCERTAINTY WITH WIND DIRECTIONS INCREASES AFTER 03Z. FORECAST MODELS LIFT THE WARM FRONT OVER THE AREA WITH NORTHERLY WINDS AT KLGA AND SW WINDS AT KJFK. COLDER OCEAN WATERS TYPICALLY PREVENTS THIS FROM HAPPENING IN THE SPRING AND DO NOT HAVE THE CONFIDENCE TO SPLIT THE HAIRS THAT THIN. LUCKILY WINDS ARE EXPECTED TO BE BETWEEN 4 KT AND 7 KT OVERNIGHT...SO HAVE FORECASTED VRB FOR NOW. OTHERWISE...WINDS EXPECTED TO BECOME NE ALL TERMINALS BY 12Z. LOW LEVEL JET DEVELOPS THIS EVENING WITH 40-50 KT SW WINDS AT 2K FT. ...NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCST CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: SEA BREEZE ENHANCEMENT (15-20KT SUSTAINED WINDS) POSSIBLE BETWEEN 20Z AND 00Z. KLGA FCSTER COMMENTS: GUSTS EXPECTED TO DIMINISH AROUND 20Z. KEWR FCSTER COMMENTS: GUSTS EXPECTED TO DIMINISH AROUND 20Z. KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED. KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED. KISP FCSTER COMMENTS: GUSTS EXPECTED TO DIMINISH BY 21Z. OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY... TUE AFTN THROUGH WED NIGHT...PERIODS OF SUB-VFR LIKELY IN SHOWERS. GUSTY WINDS/LLWS POSSIBLE. WARM FROPA WED MORNING...COLD FROPA WED NIGHT. TSTMS POSSIBLE AHEAD OF A COLD FRONT. THU...VFR WITH GUSTY NORTHWESTERLY WINDS. FRI...VFR. FRI NIGHT/SAT...SUB-VFR IN SHOWERS. STRONG SOUTHERLY WINDS POSSIBLE. && .MARINE... SCA CONVERTED TO A SCA FOR SEAS. NO OTHER CHANGES TO THE FCST. WINDS OVER ALL WATERS HAVE DROPPED TO BELOW SCA LEVELS...WITH SOME GUSTS UP TO AROUND 20 KT ATTM. WINDS WILL CONTINUE TO FALL SHORT OF SCA LEVELS OVER THE NEXT COUPLE OF DAYS AS THE SURFACE PRESSURE GRADIENT REMAINS WEAK. WAVES WILL CONTINUE TO BE ABOVE 5 FT THROUGH WEDNESDAY FOR OCEAN FACING WATERS...DUE TO RESIDUAL WAVE ENERGY AND DEVELOPING SOUTHEAST FETCH AHEAD OF AN APPROACHING COLD FRONT. WILL LIKELY EXTEND A SCA FOR HAZARDOUS SEAS BEYOND THE CURRENT EXPIRATION TIME OF THIS AFTERNOON. GUSTY WINDS AND HIGH SEAS WILL BE POSSIBLE ON THE AREA WATERS ON THURSDAY AND INTO THE FIRST PART OF THURSDAY NIGHT BEHIND THE PASSAGE OF A COLD FRONT. WINDS AND SEAS WILL GRADUALLY SUBSIDE THURSDAY NIGHT AND FRIDAY AS HIGH PRESSURE BUILDS OVER THE AREA AND THE PRESSURE GRADIENT WEAKENS. && .HYDROLOGY... ALL FLOOD WARNINGS AND STATEMENTS FOR THE OKX HSA HAVE BEEN EXPIRED OR CANCELLED. LIGHT RAIN IS POSSIBLE THIS AFTN AND TONIGHT AS A FRONT APPROACHES. PCPN AMOUNTS HOWEVER WILL BE LESS THAN 1/4 INCH SO NO SIGNIFICANT IMPACTS ARE EXPECTED ON AREA STREAMS AND RIVERS. RAIN ALONG AND N OF A NEARLY STATIONARY FRONT TUE AND TUE NIGHT. THIS EVENT WILL BE CAPABLE OF PRODUCING AROUND 1/2 INCH OF LIQUID...DEPENDING ON EXACTLY WHERE THE MAIN BAND OF FORCING SETS UP. ATTM THE MOST FAVORED AREAS WILL BE THE NRN HALF OF THE HSA AS WELL AS ACROSS NERN NJ. BASED ON FFG...RAINFALL APPROACHING MAX MODEL PROGS...LIKE THE NAM...MAY ALLOW SOME SMALL RIVERS AND STREAMS ACROSS THE LOWER HUDSON VALLEY AND NERN NJ TO REACH MINOR FLOOD LEVELS. FOR THE MAIN RIVERS...PLEASE REFER TO THE AHPS PAGE FOR POINT SPECIFIC FCST LEVELS. && .TIDES/COASTAL FLOODING... HIGH ASTRONOMICAL TIDES TONIGHT BUT SURGE IS EXPECTED TO BE MINIMAL WITH LIGHT WINDS FCST. NO COASTAL FLOODING IS THEREFORE FCST ATTM. NE FLOW AS A COLD FRONT STALLS S OF THE REGION LATE TONIGHT AND TUE. THIS WOULD LEAD TO A MINOR SURGE. THIS SURGE...COUPLED WITH THE HIGH ASTRONOMICAL TIDES...MAY LEAD TO AREAS OF MINOR COASTAL FLOODING DURING THE TUE NIGHT HIGH TIDE CYCLE. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM EDT THIS EVENING FOR ANZ350-353-355. && $$ SYNOPSIS...JST