Area Forecast Discussion
Issued by NWS Upton, NY

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KOKX 160757 AFDOKX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW YORK NY 357 AM EDT THU APR 16 2015 .SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE OVER THE REGION WILL DRIFT OUT TO SEA THROUGH TONIGHT. A WEAK COLD FRONT THEN MOVES THROUGH ON FRIDAY INTO FRIDAY EVENING ANOTHER COLD FRONT WILL MOVE THROUGH ON SATURDAY...WITH HIGH PRESSURE BUILDING BEHIND IT SATURDAY NIGHT INTO SUNDAY. THE HIGH WILL PASS TO THE EAST SUNDAY NIGHT. A LOW PRESSURE SYSTEM WILL THEN IMPACT THE AREA FROM LATE SUNDAY NIGHT INTO TUESDAY. AFTER THIS SYSTEM DEPARTS...A WEAK LOW PRESSURE TROUGH WILL LINGER INTO WEDNESDAY.
-- End Changed Discussion --
&& .NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
HIGH PRESSURE WILL BE CENTERED OVER THE REGION THIS MORNING...THEN SHIFTS EAST. AS IT DOES SO...WINDS BECOME ONSHORE. THIS...WITH HIGH PRESSURE SUBSIDENCE...WILL LIMIT THE MIXING DEPTH. BASED ON TEMPS AT THE TOP OF THIS LAYER AND CONSIDERING ONLY SOME CIRRUS...MAV/NAM MOS BLEND WITH MINOR LOCAL ADJUSTMENTS LOOKS REASONABLE FOR HIGHS.
-- End Changed Discussion --
&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
-- Changed Discussion --
CLOUDS LOWER AND THICKEN TONIGHT AHEAD OF AN APPROACHING COLD FRONT. ISENTROPIC LIFT AND MID LEVEL SHORTWAVE ENERGY COMBINE WITH INCREASING MOISTURE FOR A CHANCE OF SHOWERS LATE AT NIGHT PRIMARILY WEST OF THE CITY. SHOWERS THEN EVENTUALLY BECOME LIKELY WEST TO EAST FRIDAY MORNING AHEAD OF THE COLD FRONT. ATMOSPHERE LOOKS STABLE AS THE SHOWERS/FRONT MOVE THROUGH...SO NO MENTION OF THUNDER IN THE FORECAST. SHOWERS BECOME LESS LIKELY DURING THE AFTERNOON WITH THE WEAKENING FRONT MOVING THROUGH PART OF THE CWA...BUT WITH THE FRONT OVER THE EASTERN ZONES...AND ANOTHER MID LEVEL SHORTWAVE APPROACHING THE WESTERN ZONES...THREAT OF A SHOWER REMAINS FOR THE REST OF THE DAY. THE COLD FRONT IS NOT PARTICULARLY STRONG...AND WILL BE THROUGH ONLY A PORTION OF THE CWA BY LATE AFTERNOON. SO COLD AIR ADVECTION WON`T BE MUCH OF A FACTOR IN DETERMINING HIGH TEMPS. HOWEVER...MOSTLY CLOUDY CONDITIONS ARE EXPECTED THROUGH THE AFTERNOON...SO LEANED TOWARD THE COOLER MAV MOS GUIDANCE FOR HIGHS.
-- End Changed Discussion --
&& .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
-- Changed Discussion --
DRY FRI NIGHT AS THE COLD FRONT AND ASSOCIATED UPPER TROUGH WILL HAVE JUST PASSED THE AREA BY EVENING. WITH A DOWNSLOPE NW FLOW SETTING UP FOR SAT...EXPECT A WARN DAY THROUGHOUT...WITH HIGHS IN THE LOWER AND MID 70S...PERHAPS UPPER 70S IN NYC AND URBAN NE NJ. A POTENT UPPER SHORTWAVE MOVING ACROSS NEW ENGLAND SAT AFTERNOON WILL DRIVE A DRY COLD FRONT THROUGH BY LATE DAY...MARKED BY A WIND SHIFT AND GUSTY NW-NW WINDS FOR LATE AFTERNOON AND EVENING. HIGH PRESSURE WILL NOSE DOWN FROM THE GREAT LAKES AND CENTRAL CANADA FOR SUNDAY WHILE AN UPPER RIDGE MOVES ACROSS FROM THE WEST...SO FAIR WX SHOULD CONTINUE INTO SUNDAY...WITH NOTICEABLY COOLER TEMPS REACHING THE UPPER 50S AND LOWER 60S AFTER MORNING LOWS IN THE 40S. CLOUDS SHOULD START TO INCREASE SUNDAY AFTERNOON/EVENING AS THE UPPER RIDGE AXIS APPROACHES AND THEN PASSES BY. LEFTOVER SFC RIDGING SUNDAY NIGHT SHOULD HOWEVER HELP KEEP ANY RAIN FROM THE APPROACHING FRONTAL SYSTEM AT BAY UNTIL LATE. MAIN IMPACTS FROM THE APPROACHING FRONTAL SYSTEM SHOULD BE FELT FROM MON INTO TUE MORNING. DEEP LAYER SW FLOW AND LOW LEVEL SE FLOW WILL TRANSPORT PLENTY OF GULF AND ATLANTIC MOISTURE INTO THE REGION BETWEEN THE DEPARTING HIGH AND APPROACHING FRONT. HEAVIEST PRECIP EXPECTED LATE DAY MON INTO MON EVENING AS A SFC WAVE DEVELOPS OVER THE MID ATLANTIC REGION...HELPING FOCUS LOW LEVEL WAA AND CONVERGENCE...AND WITH MODEL FCST SHOWALTER INDICES BELOW 0C...ELEVATED CONVECTION WITH RUMBLES OF ELEVATED THUNDER ARE POSSIBLE. THE SFC WAVE SHOULD PASS JUST S OF LONG ISLAND LATE MON NIGHT AND DRIFT SLOWLY TO THE E ON TUE. AFTER MORNING RAIN AND STILL POSSIBLE THUNDER...WITH LINGERING SFC TROUGHING AND AN UPPER TROUGH APPROACHING FROM THE WEST...EXPECT MORE CHANCES FOR SHOWERS TUE AFTERNOON/NIGHT...THEN AGAIN WED AFTERNOON WITH THE APPROACH OF ANOTHER UPPER TROUGH.
-- End Changed Discussion --
&& .AVIATION /07Z THURSDAY THROUGH MONDAY/... HIGH PRESSURE WILL BUILD INTO THE REGION THIS MORNING...THEN OFFSHORE THIS AFTERNOON. VFR THROUGH THE TAF PERIOD. LIGHT AND VARIABLE AWAY FROM KNYC TERMINALS...WHERE PREVAILING FLOW WILL TEND TO THE N/NNE THROUGH 12Z. SE WINDS DEVELOP THIS MORNING...THEN INCREASE TO AROUND 10KT AFTER 16-19Z. WINDS TURN MORE SOUTHERLY AFTER 19Z. SPEEDS DECREASE AFTER 00Z. .OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY... .THURSDAY NIGHT...VFR. .FRIDAY...MVFR CONDS POSSIBLE IN -SHRA. .FRIDAY NIGHT...IMPROVING CONDITIONS. .SATURDAY...MAINLY VFR. .SUNDAY...VFR. .MONDAY...MVFR CONDS POSSIBLE IN -SHRA. && .MARINE...
-- Changed Discussion --
TRANQUIL CONDITIONS ON THE WATERS TODAY AND TONIGHT WITH AN ONSHORE FLOW OF 10 KT OR LESS THROUGH THE PERIOD. A WEAK COLD FRONT APPROACHES THE WATERS FRIDAY AFTERNOON. A FEW WIND GUSTS CLOSE TO 25 KT ARE POSSIBLE ON THE OCEAN AS WELL AS SEAS BUILDING BUILD JUST UNDER 5 FT. NOT ENOUGH CONFIDENCE IN A WIDESPREAD SCA EVENT TO GO WITH ONE AT THIS POINT. BEST CHANCE FOR SCA CONDS IN THE LONG TERM LOOKS TO BE ON MON...ON THE OCEAN...WITH THE APPROACH OF A FRONTAL SYSTEM. SE-S FLOW SHOULD INCREASE ON MON...WITH GUSTS UP TO 30 KT AND SEAS BUILDING AS HIGH AS 8-9 FT.
-- End Changed Discussion --
&& .FIRE WEATHER...
-- Changed Discussion --
CONDS FOR FIRE GROWTH/SPREAD MAY BE BE HIGH SAT AFTERNOON...WITH MIN RH 25-30 PERCENT AND WINDS GUSTING TO 20-25 MPH. WETTING RAINFALL OF 1/4 INCH ON FRI MAY KEEP FINE FUEL RH HIGH ENOUGH HOWEVER.
-- End Changed Discussion --
&& .HYDROLOGY...
-- Changed Discussion --
AROUND A QUARTER OF AN INCH OF RAIN IS EXPECTED LATE TONIGHT THROUGH FRIDAY. POTENTIAL FOR MORE SIGNIFICANT RAINFALL WITH AN APPROACHING FRONTAL SYSTEM MON-TUE IS INCREASING. HAVE INCREASED STORM TOTAL QPF TO 1- 1.5 INCHES...WITH LOCALLY HIGHER AMTS UP TO 2 INCHES IN HEAVIER SHOWERS. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEB SITE.
-- End Changed Discussion --
&& .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...NONE. && $$ SYNOPSIS...JC/GOODMAN NEAR TERM...JC SHORT TERM...JC LONG TERM...GOODMAN AVIATION...BC MARINE...JC/GOODMAN HYDROLOGY...JC/GOODMAN

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.