National Weather Service Forecast Discussion

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 171425
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1025 AM EDT THU MAY 17 2012

.SYNOPSIS...
HIGH PRESSURE CENTERED OVER THE GREAT LAKES THIS MORNING BUILDS
EAST THROUGH FRIDAY. THE HIGH THEN REMAINS OVER THE REGION THROUGH
THE WEEKEND WHILE A SURFACE LOW LINGERS OFF THE MID ATLANTIC
COAST. THE LOW WILL THEN BEGIN MOVING TO THE NORTH AT THE
BEGINNING OF THE WEEK...FOLLOWED BY A WEAK FRONT SLOWLY MOVING
THROUGH THE REGION MID WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SUNNY SKIES EXPECTED TODAY AS HIGH PRESSURE BUILDS IN FROM THE
WEST. A GUSTY NORTHERLY FLOW THIS MORNING WITH MODERATE COLD
ADVECTION...EXPECTED TO DIMINISH THIS AFTERNOON. THIS MAY ALLOW
FOR SEABREEZE DEVELOPMENT ALONG THE IMMEDIATE S COASTAL AREAS.

HIGHS WILL GENERALLY BE IN THE LOWER 70S WITH AN OFFSHORE FLOW.
THIS IS CLOSE TO SEASONABLE. USED A BLEND OF THE MET/MAV MOS.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
IT WILL BE TRANQUIL AS HIGH PRESSURE BUILDS ACROSS THE AREA WITH
PLENTY OF SUN AND ANOTHER DAY WITH HIGHS AROUND 70. PERHAPS A BIT
COOLER ALONG THE COAST AS A NE FLOW VEERS AROUND TO THE SE WITH
LOCAL SEABREEZE DEVELOPMENT EXPECTED.

DIFFERENCE ARISE IN THE MODELS AT THIS TIME WHICH WILL HAVE LITTLE
IMPACT ON THE SENSIBLE WEATHER FOR FRI. THE NAM AND RGEM FORM A
LOW ALONG A STATIONARY FRONT JUST OFF THE MID ATLANTIC COAST. THE
GFS...ECMWF AND GFES DO SO AS WELL...BUT SUBSTANTIALLY FARTHER
OFFSHORE. THE PROXIMITY OF THE LOW WILL DETERMINE THE MAGNITUDE OF
THE EASTERLY FLOW AND WHEN IF ANY RAINFALL IMPACTS THE AREA OVER
THE WEEKEND INTO EARLY NEXT WEEK. REFER TO THE LONG TERM SECTION
FOR MORE SPECIFICS.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
THE PERIOD BEGINS WITH FAIRLY GOOD AGREEMENT AMONGST THE
MODELS...KEEPING A SURFACE HIGH OVER THE NORTHEAST...AND DEVELOPING
A LOW OFF THE MID ATLANTIC COAST. HOWEVER...THE MODELS DIVERGE
QUICKLY SAT AROUND THE SURFACE LOW. 00Z NAM AND CANADIAN ARE MORE
PROGRESSIVE WITH BRINGING THE LOW TO THE NORTH AND CLOSER TO THE
SHORE...WHILE THE 00Z GFS AND ECMWF KEEP IT FURTHER OFFSHORE.
ALOFT...RIDGING BUILDS IN...WITH THE GFS AND ECMWF BEING MORE
DOMINANT IN THE HIGH OVER THE MID ATLANTIC REGION...HELPING TO
SUPPRESS THE LOW OFFSHORE. WITH SUCH MODEL INCONSISTENCIES...WILL
SIDE IN FAVOR OF THE PREVIOUS FORECAST THOUGHTS AND LEAN TOWARDS A
GFS/ECMWF BLEND INTO THE BEGINNING OF THE WEEK.

WITH THIS IN MIND...HIGH PRESSURE DOMINATES THE NORTHEAST...KEEPING
DRY AND WARM CONDITIONS IN PLACE FOR THE WEEKEND. WAA WILL PUSH
ABOVE NORMAL TEMPS INTO THE REGION...WITH 925MB TEMPS REACHING NEAR
15 DEGREES...BRINGING HIGHS INTO THE 70S AND NEARING 80...AND LOWS
IN THE 50S. TEMPS REMAIN WARM THROUGH THE FIRST PART OF THE WEEK
WITH THE WARMER AIR BEING ADVECTED IN. HOWEVER...DEPENDING ON TIMING
OF PRECIP...MAY SEE SLIGHTLY COOLER TEMPS THAN FORECASTED.

GRADUALLY INCREASED POPS AND SKY COVER FROM THE SOUTH TO NORTH
SUNDAY NIGHT INTO THE FIRST PART OF THE WEEK AS BOTH THE GFS AND
ECMWF PROGRESS THE SURFACE LOW TO THE NORTH. HOWEVER...DUE TO THE
UNCERTAINTY IN TIMING AND STRENGTH OF THIS LOW...WENT WITH ONLY CHC
POPS FOR NOW. A STRONGER LOW PRESSURE SYSTEM TRAVERSING SOUTHERN
CANADA WILL DRAG A COLD FRONT THROUGH THE REGION SOMETIME LATE
TUESDAY INTO EARLY WED...WITH THE FRONT SLOWLY EXITING THE REGION
EVENTUALLY BY THURS. CURRENT THINKING IS THE BEST CHC FOR PRECIP
WILL BE TUES AND WED AS THE UPPER LEVEL RIDGING WEAKENS AND AN UPPER
LEVEL CLOSED LOW MOVES THROUGH AHEAD OF MULTIPLE SHORTWAVES.
SOUNDINGS INDICATE THAT WITH PLENTY OF LIFT WITH THE SURFACE LOW AND
APPROACHING FRONT...SURFACE INSTABILITY WILL BE ENOUGH TO PRODUCE
SOME THUNDERSTORMS.

&&

.AVIATION /15Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --HIGH PRESSURE BUILDS IN FROM THE WEST.

NORTHERLY WINDS WILL AVERAGE 12 KT...THEN DIMINISH TO 5-10 KT
LATER TODAY. WINDS EVENTUALLY DIMINISH TO 5 KT OR LESS AFTER SUNSET.

VFR WITH UNLIMITED VSBYS THROUGH THE TAF PERIOD.

SEA BREEZE REMAINS POSSIBLE AT COASTAL TERMINALS THIS AFTERNOON. KEPT
WIND SHIFT AT KJFK/KBDR/KGON AT THIS TIME.

...NY METRO ENHANCED AVIATION WEATHER SUPPORT...

DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN
BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE)

KJFK FCSTER COMMENTS: SEA BREEZE POSSIBLE BETWEEN 19-21Z.

KLGA FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CHANGES IN WIND
SPEED.

KEWR FCSTER COMMENTS: AMENDMENTS POSSIBLE FOR CHANGES IN WIND
SPEED.

THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH
IMPLIES  SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD.

KTEB FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KHPN FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

KISP FCSTER COMMENTS: NO UNSCHEDULED AMENDMENTS EXPECTED.

OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
.FRIDAY THROUGH SUNDAY...VFR.
.MONDAY...VFR LIKELY...BUT WILL HAVE TO KEEP AN EYE ON WEAK LOW
PRESSURE TO THE SOUTH FOR POSSIBLE IMPACTS TO CIGS/VSBY.-- End Changed Discussion --

&&

.MARINE...
N WINDS WITH GUSTS UP TO 20 KT THIS MORNING WILL DIMINISH THIS
AFT....WITH POSSIBLE SEABREEZE DEVELOPMENT ALONG NEARSHORE WATERS.

THE WEEKEND WILL BEGIN WITH SUB-SCA CONDITIONS...BUT WITH THE
DEVELOPING SURFACE LOW TO THE SOUTH...THE OCEAN WATERS MAY SEE
BUILDING SEAS TO AROUND 5 FT. THE HIGHER SEAS ARE EXPECTED TO
PERSIST THROUGH THE WEEKEND INTO THE FIRST PART OF THE WEEK. WINDS
WILL GENERALLY BE FROM THE EAST TO NORTHEAST...HOWEVER REMAINING
LESS THEN SCA CRITERIA.

&&

.HYDROLOGY...
NO SIGNIFICANT PRECIP IS EXPECTED THROUGH THE WEEKEND. THERE IS
THE POTENTIAL FOR RAINFALL MON AND TUE SHOULD LOW PRESSURE ALONG
THE MID ATLANTIC COAST MATERIALIZE AND PUSH NORTHWARD.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...SEARS/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...SEARS
AVIATION...BC/MPS
MARINE...SEARS/DW
HYDROLOGY...SEARS

NWS OKX Office Area Forecast Discussion