Area Forecast Discussion
Issued by NWS Upton, NY

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000
FXUS61 KOKX 230604
AFDOKX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
204 AM EDT WED APR 23 2014

.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE AREA EARLY THIS MORNING. LOW
PRESSURE OVER NORTHERN NEW ENGLAND WILL DEEPEN AND MOVE SLOWLY
EAST OFF THE NEW ENGLAND COAST WEDNESDAY INTO WEDNESDAY
NIGHT...WHILE HIGH PRESSURE BUILDS IN THROUGH FRIDAY. A FRONTAL
SYSTEM WILL IMPACT THE REGION OVER THE WEEKEND. ANOTHER HIGH WILL
BUILD FROM THE NORTH EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS IS OFTEN THE CASE...COLD FRONTS OFTEN ARE SLOWER THAN THE
GUIDANCE. LATEST 05Z ANALYSIS...PLACES THE FRONT RIGHT ON TOP OF
NYC WITH WINDS SHIFTING TO THE W. ALREADY SEEING GUSTS APPROACHING
20 KT AT KMGJ. TO THE EAST...SOME PATCHY FOG WITH LIGHT WINDS AND
LOW-LEVEL MOISTURE IN PLACE. THIS SHOULD BE SHORT-LIVED AS WINDS
BECOME WESTERLY WITH DRIER AIR GRADUALLY FILTERING IN BEHIND THE
COLD FRONT. HAVE ALSO ADDED A SLIGHT CHANCE OF SHOWERS ACROSS THE
ENTIRE FORECAST AREA WITH AN AMPLIFYING SHORT WAVE TROF APPROACHING
FROM THE WEST. THESE SHOULD BE LOW-TOPPED SHOWERS WITH LITTLE
FANFARE AND LIGHT RAINFALL.

LOWS TONIGHT 45-50 MORE IN LINE WITH LATEST GFS LAMP.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
BEHIND THE COLD FRONT A COOLER THAN NORMAL AND VERY DRY AIR MASS
WILL BUILD IN. HIGH PRESSURE WILL BE SLOW TO BUILD IN THOUGH WITH
THE PARENT LOW STILL PRETTY STRONG FOR SPRING WITH A CENTRAL
PRESSURE OF 995MB ALONG THE COAST OF NEW ENGLAND. THIS DEEPENS
APPROXIMATELY 5 MB THROUGH THE DAY. GUSTY NW FLOW DEVELOPS.

THE GUSTY NW FLOW INCREASES TOWARDS EVENING WITH THE STRONGER LOW
OFF THE NEW ENGLAND COAST. THIS SLOWLY PUSHES FARTHER EAST
WEDNESDAY NIGHT. THIS WILL KEEP TEMPERATURES FROM FALLING TOO MUCH
DESPITE THE ENTRANCE OF HIGH PRESSURE FROM THE WEST.

TEMPERATURES WERE A BLEND OF MAV/MET/NAM12 FOR WEDNESDAY AND
WEDNESDAY NIGHT. THEY WILL GENERALLY BE BELOW NORMAL BY SEVERAL
DEGREES...MORE SO AT NIGHT.

ALSO...STRENGTHENING UPPER LEVEL TROUGH WITH ANOTHER VORT MAX
MOVING SOUTHEAST THROUGH THE REGION ALONG WITH ITS UPPER LEVEL JET
STREAK AND CLOSER PROXIMITY OF LEFT FRONT QUAD WILL CREATE
VERTICAL FORCING. HENCE...SOME SHOWERS WILL BE POSSIBLE...MORE THE
FAR NORTHERN INTERIOR SECTIONS. HOWEVER...THIS WILL BE COMPETING A
CONTINUING DRYING OF THE BOUNDARY LAYER WITH NW FLOW.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE OCCLUDED LOW OVER THE ATLANTIC WILL CONTINUE TO ACT AS A WIND
MACHINE OVER THE REGION THU...WITH DEEP MIXING AND BORDERLINE WIND
ADVY CONDITIONS THE RESULT. 50 KT WINDS RELEGATED TO AOA H85 PER THE
12Z MODEL DATA...AS A RESULT CAPPED GUSTS AT 45 MPH. DEEP SUBSIDENCE
SHOULD RESULT IN A COMPLETELY SUNNY DAY. THE WINDS WILL CALM DOWN ON
FRI AS H5 RIDGE BUILDS INTO THE CWA. TEMPS A FEW DEGREES
WARMER...ESPECIALLY ACROSS THE INTERIOR WITH A WARMER AIR MASS IN
PLACE. THE ONSET OF SEA BREEZE FLOW AND RETURN SLY FLOW SHOULD
ACTUALLY KEEP THE S COASTS COOLER THAN THU. WEAK FRONTAL SYSTEM WILL
ALLOW FOR INCREASING CLOUDS IN THE AFTN...WITH PERHAPS AN ISOLD
SHRA. THE GFS IS THE FASTED AND MOST AGGRESSIVE WITH THIS...AND IF
THE NAM AND ECMWF ARE CORRECT A COMPLETELY DRY DAY CAN BE EXPECTED.
ONLY 20 POPS IN THE FCST ATTM. MODEL TIMING IS BETTER WITH AN UPR
WAVE AND PERIOD OF LGT RAIN FRI NGT INTO SAT. HIGH CHC POPS FOR
THIS. THERE HAS BEEN SOME HINT OF LOW PRES DEVELOPING OFF THE NEW
ENGLAND COAST AS THE WAVE TRACKS OFFSHORE...SPINNING SOME LGT PCPN
IN FROM THE N SAT NGT AND SUN. LOW CHC POPS MAINTAINED IN THE FCST
DUE TO THE GFS CONSISTENCY. FOR MON AND TUE...THE GFS IS COMPLETELY
DRY WITH HIGH PRES RIDGING SWD FROM CANADA. THE ECMWF HOWEVER HAS
BROUGHT THE WARM/STATIONARY FRONTAL ZONE FURTHER NWD INTO THE
REGION...WHICH WOULD PRODUCE OVC WX WITH CHCS FOR RAIN. THE FCST
SIDES WITH THE MORE CONSISTENT DRY SOLNS OF THE 12Z GFS AND 00Z
ECMWF.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
A COLD FRONT PASSES THROUGH DURING THE PRE-DAWN HOURS WITH HIGH
PRESSURE BUILDING IN BEHIND IT TODAY.

VFR. SOME SUB-VFR POSSIBLE BEFORE 11-12Z EAST OF THE CITY WITH ISO
-SHRA AND REDUCED VSBYS PRECEDING WINDS PICKING UP FROM THE WNW.

WINDS GENERALLY WNW BEFORE AROUND 12Z...THEN NW THEREAFTER.
OCCASIONAL GUSTS TO AROUND 20KT FOR THE CITY TERMINALS BEFORE 09Z.
WINDS PEAK THIS AFTN WITH GUSTS MOSTLY AROUND 35KT...HOWEVER
OCCASIONAL GUSTS TO 40KT ARE POSSIBLE.

WIND DIRECTION IN THE CITY FAVORING SOUTH OF 310 MAGNETIC UNTIL
AROUND 13-14Z...THEN NORTH OF IT THEREAFTER.


.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
.WED NIGHT...VFR. NW G25KT.
.THU...VFR. NW G30KT.
.FRI...VFR. CHC LATE DAY/NIGHTTIME -SHRA AND MVFR.
.SAT...MOSTLY VFR...HOWEVER CHC -SHRA AND MVFR.
.SUN...VFR. NW G20-25KT.

&&

.MARINE...
SUB SCA CONDS EXPECTED OVERNIGHT. GALES SHOULD DEVELOP WEDNESDAY
THROUGH WEDNESDAY NIGHT WITH SLOW PROGRESSION OF STRONG LOW
PRESSURE MOVING OFF NEW ENGLAND COAST WEDNESDAY INTO WEDNESDAY
NIGHT CREATING TIGHT PRESSURE GRADIENT. THERE COULD BE SOME
PERIODS WHERE WINDS ARE BELOW GALES EARLY WEDNESDAY.

GALES LIKELY TO CONTINUE THRU THU WITH LOW PRES S OF THE MARITIMES.
THE LOW DEPARTS WITH WINDS AND SEAS BLW SCA LVLS FRI. WIND AND SEAS
COME UP SAT WITH THE PASSAGE OF A FRONTAL SYSTEM...WITH SCA
CONDITIONS POSSIBLE ESPECIALLY ON THE OCEAN. SCA CONDITIONS POSSIBLE
ON SUN WITH NLY FLOW...THEN HIPRES ON MON.

&&

.FIRE WEATHER...
WEDNESDAY...MIN RH VALUES WILL DROP TO 35 TO 45 PERCENT MOST
LOCATIONS WITH SOME SPOTS REACHING DOWN TO 30 PERCENT. THIS
COMBINED WITH WINDS GUSTING 30 TO 40 MPH WILL CREATE SOME ENHANCED
FIRE SPREAD CONDITIONS BUT NOT QUITE AS PROMINENT AND PRONOUNCED
AS FIRE WEATHER CONDITIONS ON THURSDAY. PLUS...THERE COULD BE A
FEW SHOWERS DURING THE DAY WHICH FURTHER LIMITS FIRE WEATHER
POTENTIAL WEDNESDAY.

STRONG NW WINDS GUSTING UP TO 45 MPH AND MIN RH FALLING INTO THE
TEENS IN SPOTS WILL LIKELY RESULT IN RED FLAG CONDITIONS ON THU.
CONSULTATION WITH LAND MANAGERS INDICATES THAT VENTILATION ON WED
SHOULD PRIME THE FUELS FOR THU...EVEN IF 1/4 INCH OF RAIN OR MORE
OCCURS THRU TNGT. AS A RESULT...A FIRE WX WATCH HAS BEEN ISSUED FOR
THE ENTIRE CWA THU.

&&

.HYDROLOGY...
A FEW TENTHS OF AN INCH OF RAIN ARE POSSIBLE FRI NGT AND SAT.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
     EVENING FOR CTZ005>012.
NY...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
     EVENING FOR NYZ067>075-078>081-176>179.
NJ...FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
     EVENING FOR NJZ002>004-006-103>108.
MARINE...GALE WARNING FROM 6 AM THIS MORNING TO 6 PM EDT THURSDAY FOR
     ANZ330-335-338-340-345-350-353-355.

&&

$$






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