938
FXUS61 KOKX 272045
AFDOKX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW YORK NY
445 PM EDT MON JUL 27 2026
WHAT HAS CHANGED
FLOOD WATCH IN EFFECT FOR THE LOWER HUDSON VALLEY, NORTHEAST
NJ, NYC, PORTIONS OF WESTERN LI, AND SOUTHWEST CT FROM TUESDAY
MORNING THROUGH WEDNESDAY MORNING.
KEY MESSAGES
1) SCATTERED SHOWERS AND THUNDERSTORMS INTO EARLY THIS EVENING.
AN ISOLATED SEVERE THUNDERSTORM IS POSSIBLE.
2) HEAVY SHOWERS AND THUNDERSTORMS WILL BRING THE POTENTIAL FOR
FLASH FLOODING, MAINLY TUESDAY AFTERNOON THROUGH WEDNESDAY
MORNING. THERE IS THE POTENTIAL FOR LIFE THREATENING FLOODING
DURING THIS TIME.
3) POTENTIAL FOR MINOR COASTAL FLOODING MID TO LATE WEEK WITH
A COASTAL LOW.
DISCUSSION
KEY MESSAGE 1
WIDELY TO SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED
THROUGH EARLY THIS EVENING.THE ENVIRONMENT IS MORE PULSE-LIKE
WITH WEAK SHEAR AND MODERATE TO HIGH CAPE. AN ISOLATED SEVERE
THUNDERSTORM IS POSSIBLE. LIFE CYCLE OF THESE STORMS WILL BE
SHORT.
THE ACTIVITY IS FORECAST TO WEAKEN QUICKLY THIS EVENING WITH THE
LOSS OF DAYTIME HEATING. HOWEVER, THE CAMS DO SHOW THE POTENTIAL
FOR SCATTERED SHOWERS AND THUNDERSTORMS LATE TONIGHT INTO
TUESDAY MORNING ALONG THE COAST AS THE AIRMASS DESTABILIZES AND
LOW-LEVEL CONVERGENCE DEVELOPS IN A STRENGTHENING SOUTHERLY
FLOW.
KEY MESSAGE 2
A HIGHLY ANOMALOUS SUMMERTIME PATTERN WILL FEATURE THE FORMATION
OF AN UPPER LOW LATE TONIGHT INTO TUESDAY, AS SHORTWAVE ENERGY
DROPS SOUTHEAST ACROSS THE LOWER GREAT LAKES INTO UPSTATE NY.
THE ASSOCIATED SURFACE LOW OCCLUDES AND FALLS BELOW 1000 MB. FOR
THIS TIME OF YEAR, BOTH THE 500 MB AND 1000 MB GEOPOTENTIAL
HEIGHTS ARE NEAR ALL TIME LOWS (WELL BELOW THE TENTH PERCENTILE
USING THE NAEFS). THE COMBINATION OF LARGE SCALE LIFT AND PWAT
VALUES INCREASING TO AROUND 2 INCHES IS SETTING THE STAGE FOR A
SIGNIFICANT RAINFALL EVENT ACROSS THE REGION. THE HEAVIEST AXIS
AT THIS TIME IS FORECAST TO BE ACROSS NYC, NE NJ, AND THE LOWER
HUDSON VALLEY, WITH 2 TO 5 INCHES OF RAINFALL. LOCALIZED HIGHER
AMOUNTS ARE POSSIBLE. THE 12Z HREF SHOWS A HIGH NEIGHBORHOOD
PROBABILITY OF 70%+ FOR AN INCH PLUS/HOURLY RATES BY TUESDAY
EVENING AND 5 INCH STORM TOTALS IN THIS CORRIDOR BY WEDNESDAY
MORNING. IT ALSO SHOWS A SIGNIFICANT SIGNAL FOR 3 INCHES/3 HOURS
AT 10 TO 30 PERCENT. WHILE THIS MAY SEEM LOW, THESE PROBABILITIES
ARE A GOOD SIGNAL FOR HIGH HOURLY PRECIPITATION RATES. THE WPC
URBAN RAIN RATE DASHBOARD (URRD) IS ALSO SHOWING SIGNIFICANT
SUPPORT FOR THESE RATES WITH SOME MEMBERS OF THE ENSEMBLE
SUPPORTING HOURLY RATES WITH ANNUAL RETURN INTERVALS (ARI) OF 50
TO 100 YEARS. BOTTOM LINE, THE INGREDIENTS ARE THERE FOR A
POTENTIALLY SIGNIFICANT RAINFALL EVENT. HOWEVER THERE ARE
LIKELY TO BE SOME ADJUSTMENTS TO THIS AXIS OVER THE NEXT 24
HOURS.
THE RAINFALL WILL LIKELY COME IN SOUTH TO NORTH ORIENTED BANDS
AS ADVERTISED BY THE CAMS AS ENERGY ROUNDS THE UPPER LOW ALONG
WITH GOOD UPPER LEVEL DIVERGENCE. FOR MUCH OF TUESDAY, THESE
BANDS OF SHOWERS AND THUNDERSTORMS WILL LIKELY BE CONFINED TO
THE WATCH AREA, WEAKENING AS THEY PIVOT EAST. HOWEVER, AS THE
UPPER SUPPORT AND LOW LEVEL JET WORK EAST TUESDAY NIGHT, THE
HEAVY RAINFALL WILL LIKELY WORK ACROSS LI AND SOUTHEAST CT.
GUIDANCE GENERALLY KEEPS TOTAL AT 2 INCHES OR LESS ACROSS THESE
LOCATIONS. HOWEVER, THERE IS THE POTENTIAL FOR HIGHER TOTALS
AND THIS AREA WILL HAVE TO BE WATCHED FOR POSSIBLE EXPANSION OF
THE FLOOD WATCH FOR TUESDAY NIGHT INTO WEDNESDAY.
THE SPC MARGINAL RISK FOR SEVERE WEATHER ON TUESDAY GETS JUST
INTO SOUTHERN PORTIONS OF THE NY/NJ METRO. THERE IS DECENT
TURNING OF THE VERTICAL WIND PROFILE WITH A 2 PERCENT CHANCE FOR
TORNADIC DEVELOPMENT. LCLS ARE LOW AND INSTABILITY IS MARGINAL.
HOWEVER. LAPSE RATES ARE POOR AND DEEP CONVECTION SUPPORTING
SEVERE WEATHER IS UNLIKELY.
AREAS OF SHOWERS WITH EMBEDDED THUNDERSTORMS WILL LIKELY
CONTINUE WEDNESDAY INTO THURSDAY WITH THE UPPER LOW TRACKING
SLOWLY EAST ACROSS THE NORTHEAST. THE DEEP MOISTURE WILL SHIFT
TO THE EAST AND HOURLY RATES WILL BE SIGNIFICANTLY LOWER.
HIGH TEMPERATURES WILL REMAIN BELOW NORMAL DURING THIS TIME WITH
THE CLOUD COVER AND RAINFALL. LOWS THOUGH WILL BE CLOSER TO
NORMAL.
KEY MESSAGE 3
WITH THE APPROACH OF A FULL MOON MIDWEEK AND AN ONSHORE E/SE
FLOW WITH LOW PRESSURE PASSING CLOSE BY, MINOR COASTAL FLOODING
IS A POSSIBILITY. THERE IS STILL A FAIR AMOUNT OF UNCERTAINTY
AT THIS TIME. LATEST FORECAST BRINGS SOME OF THE SOUTH SHORE
BACK BAY LOCATIONS OF LI AND WESTERN LI SOUND TO JUST BELOW
MINOR COASTAL FLOOD BENCHMARKS DURING THE EVENING/NIGHTTIME
HIGH TIDE CYCLES.
AVIATION /19Z MONDAY THROUGH SATURDAY/
MOSTLY VFR, HOWEVER MVFR IN PROB30 FOR TSRA POSSIBLE THIS AFTERNOON
INTO EARLY EVENING FOR ALL BUT KBDR/KGON. MVFR CIGS POSSIBLE LATE
TONIGHT INTO THE TUESDAY MORNING PUSH ALONG WITH POTENTIAL SHOWERS.
MVFR AND SHOWERS ARE THEN LIKELY TUESDAY AFTERNOON AND EVENING WITH
A THUNDERSTORM AND BRIEF IFR VSBYS POSSIBLE IN HEAVIER RAIN.
S/SE WINDS AROUND 10KT, BECOMING LIGHTER AND VEERING SLIGHTLY.
S-SE GUSTS NEAR 20KT TUESDAY AFTERNOON.
...NY METRO (KEWR/KLGA/KJFK/KTEB) TAF UNCERTAINTY...
CHANCE THAT PROB30 FOR TSRA THIS AFTN/EVENING COULD BE REMOVED WITH
AMENDMENTS.
OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY
TUESDAY PM: MVFR IN SHRA/TSTM, CHC IFR VSBYS IN HEAVY RAIN. S-SE
WINDS G15-20KT.
WEDNESDAY: MOSTLY MVFR/VFR CONDITIONS LIKELY WITH SHOWERS.
THUNDERSTORMS AND BRIEF IFR POSSIBLE.
THURSDAY: MVFR OR LOWER POSSIBLE. SHOWERS POSSIBLE AND A SLIGHT
CHANCE OF A THUNDERSTORM. N-NW WIND G15-20KT.
FRIDAY: MAINLY VFR, CHANCE OF AN AFTERNOON SHOWER OR TSTM.
SATURDAY: MAINLY VFR.
DETAILED INFORMATION, INCLUDING HOURLY TAF WIND COMPONENT FORECASTS,
CAN BE FOUND AT: HTTPS:/WWW.WEATHER.GOV/ZNY/N90
MARINE
A SLOW MOVING LOW PRESSURE SYSTEM WILL BRING SMALL CRAFT ADVISORY
CONDITIONS TO THE WATERS STARTING TUESDAY AFTERNOON. GUSTS ARE
FORECAST TO PEAK AROUND 25 TO 30 KT TUESDAY EVENING THROUGH
WEDNESDAY MORNING AND OCEAN SEAS PEAKING AT 5 TO 6 FT TUESDAY
NIGHT THROUGH WEDNESDAY. THERE IS STILL SOME UNCERTAINTY WITH
EXACT LOW TRACK AND STRENGTH OF WINDS.
THEREAFTER, THE PRESSURE GRADIENT LOOKS TO DECREASE AND SUB SCA
CONDITIONS ARE THEN EXPECTED THROUGH THE WEEKEND.
RIP CURRENTS...
THERE IS A MODERATE RISK OF RIP CURRENTS INTO THIS EVENING WITH
A S FLOW PEAKING AROUND 10 KT AND A WEAK E SWELL AT 2 FT 7S.
THE MODERATE RISK CONTINUES ON TUESDAY, BUT THERE IS POTENTIAL FOR A
HIGH RISK LATE IN THE DAY. FOR NOW STUCK WITH A MODERATE, BUT
CONTINUE TO MONITOR THE FORECAST AS A RIP CURRENT STATEMENT MIGHT BE
NEEDED. A S/SE FLOW INCREASES TO 15-20 KT WITH A 4FT 5S S/SE SWELL.
BOTH RCMOS AND LOCAL GUIDANCE SHOW BORDERLINE MODERATE/HIGH RISK BY
THE AFTERNOON.
OKX WATCHES/WARNINGS/ADVISORIES
CT...FLOOD WATCH FROM TUESDAY MORNING THROUGH WEDNESDAY MORNING FOR
CTZ005-006-009-010.
NY...FLOOD WATCH FROM TUESDAY MORNING THROUGH WEDNESDAY MORNING FOR
NYZ067>075-176>179.
NJ...FLOOD WATCH FROM TUESDAY MORNING THROUGH WEDNESDAY MORNING FOR
NJZ002-004-006-103>108.
MARINE...SMALL CRAFT ADVISORY FROM 6 PM TUESDAY TO 2 PM EDT WEDNESDAY
FOR ANZ331-332-340.
SMALL CRAFT ADVISORY FROM NOON TUESDAY TO 6 AM EDT WEDNESDAY
FOR ANZ335-338-345-355.
SMALL CRAFT ADVISORY FROM 6 PM TUESDAY TO 3 PM EDT WEDNESDAY
FOR ANZ350.
SMALL CRAFT ADVISORY FROM NOON TUESDAY TO 2 PM EDT WEDNESDAY
FOR ANZ353.
DISCUSSION...DW
AVIATION...JC
MARINE...DW
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