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FXUS61 KOKX 091538
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
1038 AM EST TUE MAR 9 2010

.SYNOPSIS...
HIGH PRESSURE BUILDS INTO THE REGION THROUGH WEDNESDAY...THEN
SLOWLY RETREATS NORTHEAST THROUGH THE END OF THE WEEK. A POTENT
STORM SYSTEM WILL SLOWLY TRACK WEST FROM THE CENTRAL PLAINS FROM
THURSDAY THROUGH SUNDAY...THEN GRADUALLY PULL AWAY TO OUR EAST
EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPERATURES ARE ALREADY AT PREVIOUS FORECAST HIGHS FOR TODAY AT
MANY LOCATIONS. BASED ON FORECAST MIXING TO AROUND 875 HPA IN
BUFKIT SOUNDINGS...HAVE GONE AHEAD AND BUMPED UP HIGHS ABOUT 5
DEGREES AT MOST LOCATIONS...THE EXCEPTION IS OVER FAR NW ZONES
WHICH STILL HAVE SNOW COVER...THERE HAVE USED NAM 2-METER
TEMPERATURES (WHICH DO FAIRLY WELL WITH A SNOW PACK). THE RESULT
IS CAN EXPECT HIGHS UPPER 50S TO AROUND 60 NYC METRO...UPPER 40S
TO AROUND 50 FAR NW...AND LOWER TO MID 50S ELSEWHERE. WILL
CONTINUE TO MONITOR AND TEMPS...AND MIGHT HAVE TO UPDATE AGAIN IF
MIXING ENDS UP BEING HIGHER THAN 875 HPA.

WITH BOUNDARY LAYER WINDS OVER WESTERN AREAS FORECAST TO FALL TO
10KT OR LESS...FORECAST HIGHS OVER NYC AS DESCRIBED ABOVE...AND
WATER TEMPERATURES AROUND 40...COULD SEE AT LEAST SOME SEA BREEZE
INDUCED BACKING OF THE WINDS AROUND NY HARBOR/S SHORE OF FAR
WESTERN LONG ISLAND AND NYC.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
MAINLY A CLOUD AND TEMPERATURE FORECAST THROUGH WED. TEMPERATURES
TONIGHT SHOULD BE MORE UNIFORM TONIGHT COMPARED TO LAST NIGHT AS
HIGH PRES SETS UP OVER THE CWA. LITTLE CHANGE MADE TO OFFICIAL
GRIDS.

CLOUDS INCREASE WED WITH MID LEVEL MOISTURE BEGINNING TO ADVECT
IN. ONSHORE FLOW WILL KEEP HIGH TEMPS WEDNESDAY COOLER THAN TODAY.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
FOCUS REMAINS ON THE LATE WEEK/WEEKEND STORM.

STILL SOME UNCERTAINTY WITH PRECIPITATION CHANCES WED NIGHT. 00Z
GFS/GEM/ECMWF ALL PRODUCE SOME SPOTTY PRECIPITATION ACROSS THE
CWA. VERY LIGHT. FOR NOW WILL KEEP THE FCST DRY AND ALLOW FOR A
SOLID CONSENSUS TO DEVELOP. NAM IS LIKELY TOO SLOW WITH THE ONSET
OF PRECIPITATION AS IT HAS BEEN MANY TIMES THIS WINTER.

LIGHT RAIN CHANCES INCREASE THU WITH SPRINKLES POSSIBLE BY SUNRISE
SW OF THE METRO. TIME HEIGHTS SHOW LIFT IS MINIMAL...SO HEAVY RAIN
NOT EXPECTED THU. MOISTURE STEADILY INCREASES THROUGH FRI WITH
RAIN LIKELY LATE THU NIGHT AND FRI. MOISTURE TRANSPORT VECTORS
FROM THE GULF TO THE ATLANTIC AND INTO THE CWA. MODERATE RAINFALL
RATES WILL THEREFORE BE POSSIBLE DURING THE PERIOD.

MAIN EVENT WILL BE WHEN THE H5 LOW REACHES THE OH VALLEY. 80-85KT
SOUTHEASTERLY LOW LEVEL JET WILL BEGIN TO CRANK AND PRODUCE STRONG
LIFT ACROSS THE CWA. HEAVY RA LIKELY. GFS HAS BACKED OFF SLIGHTLY
ON PW/S...WITH MAXES ABOUT 250 PERCENT OF NORMAL. THIS MAY BE
UNDERDONE BASED ON WATER VAPOR IMAGERY SHOWING AN UNINTERRUPTED
STREAM OF SUBTROPICAL MOISTURE FROM THE WESTERN PACIFIC INTO THE
GULF OF MEXICO.

FOR TIMING...ECMWF IS SLOWER THAN THE GFS WITH THE H5 LOW. A
BLEND WAS USED PUTTING THE FAVORED WINDOW FOR HEAVY PRECIPITATION
AT THIS TIME SAT-SAT NIGHT.

STORM SLOWLY WINDS DOWN SUN AND MON WITH UPPER LOW COOLING THE
COLUMN FOR A MIX OR CHANGE TO SNOW SUN NIGHT ACROSS THE INTERIOR.

&&

.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
VFR THROUGH THE TAF PERIOD.

LIGHT W-NW FLOW THROUGH THIS MORNING...THEN NW FLOW INCREASES TO
8-10 KT. SOME GUSTS TO 20-25KT WERE BEING REPORTED
OVERNIGHT...MAINLY AT THE CITY TERMINALS. WHILE SOME OCCASIONAL
GUSTS WILL BE POSSIBLE...CONFIDENCE NOT HIGH ENOUGH TO CARRY IN
THE TAFS AT THIS TIME.

NONE OF THE LATEST GUIDANCE SHOWING SEA BREEZE DEVELOPING THIS
AFTERNOON AND WILL KEEP THEM OUT OF THE TAFS FOR NOW. THIS WILL
NEED TO BE MONITORED THIS MORNING.

WINDS DIMINISH THIS EVENING WITH LIGHT AND VARIABLE WINDS
DEVELOPING OVERNIGHT.

SKC THROUGH LATE MORNING...THEN FEW-SCT AT 4K FT CU WILL DEVELOP
WITH DIURNAL HEATING.

KJFK AFTERNOON HOURLY WIND FORECAST IN SUPPORT OF RUNWAY CONSTRUCTION ALL
WIND DIRECTIONS ARE TRUE...ADD 13 DEGREES FOR MAGNETIC
     09/19Z 32010KT
     09/20Z 32008KT
     09/21Z 31007KT
     09/22Z 31006KT
     09/23Z 32005KT
     10/00Z 33004KT
     10/01Z VRB03KT
     10/02Z 34004KT
     10/03Z 35004KT

OUTLOOK 06Z WEDNESDAY THROUGH SATURDAY...
TUE NIGHT THROUGH WED NIGHT...VFR.
THU...SUB-VFR POSSIBLE.
THU NIGHT THROUGH SAT...SUB-VFR LIKELY WITH INCREASING SE FLOW.
HEAVY RAIN POSSIBLE FRI NIGHT THROUGH SAT.

&&

.MARINE...
MINOR CHANGES MADE WITH THIS UPDATE...MAINLY LOWERING SEAS A BIT
OVER NORTHERN PARTS OF THE COASTAL OCEAN ZONES TO REFLECT SEAS OF
1 FT CURRENTLY BEING OBSERVED.

HIGH PRESSURE OVER THE AREA WATERS WILL KEEP CONDITIONS BELOW SMALL
CRAFT THROUGH MID WEEK.

WINDS WILL INCREASE OUT OF THE EAST/SOUTHEAST AND OCEAN WATERS
EXPECTED TO BUILD ABOVE SCA CRITERIA ON FRIDAY AS LOW PRESSURE
BEGINS TO IMPACT THE WATERS. VERY ROUGH CONDITIONS ON ATLANTIC
WATERS THROUGH SATURDAY WITH WAVE HEIGHTS REACHING THE 10 TO 12
FOOT RANGE. A BRIEF PERIOD OF GALES MAY BE POSSIBLE SATURDAY OR
SATURDAY NIGHT DEPENDING ON THE SPEED AND PLACEMENT OF THE LOW
PRESSURE SYSTEM NEAR BY THE AREA WATERS.

&&

.HYDROLOGY...
PERIODS OF RAIN...HEAVY AT TIMES...WILL BEGIN LATE THU NIGHT OR
FRI...AND LAST THROUGH SAT NIGHT. IT IS STILL TOO FAR OUT TO
DETERMINE EXACTLY WHEN THE HEAVIEST BANDS WILL OCCUR. SMALL RIVERS
AND STREAMS WILL BE MOST PRONE TO FLOODING...HOWEVER...WITH
UPSTREAM SNOW MELT HIGHLY LIKELY AND A LONG DURATION PRECIPITATION
EVENT...MAJOR RIVERS WILL NEED TO BE MONITORED. AREAS OF URBAN AND
POOR DRAINAGE FLOODING CAN BE EXPECTED IN THIS EVENT.

&&

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

&&

$$

SYNOPSIS...MALOIT/JMC
NEAR TERM...MALOIT
SHORT TERM...JMC
LONG TERM...JMC
AVIATION...BC
MARINE...MALOIT/BC
HYDROLOGY...JMC