212
FXUS61 KOKX 271138
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
738 AM EDT Sun Jul 27 2025
.SYNOPSIS...
High pressure moves offshore as a weak frontal system approaches the
area this morning. The front heads east of the region tonight
into early Monday. High pressure then returns Monday into
Tuesday. A cold front approaches Wednesday and moves across the
area Wednesday night into Thursday. High pressure builds in
from the Great Lakes Friday into next Saturday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
GOES-16 6.95um WV channel depicts a mid/upper shortwave racing
through the Great Lakes this morning. A weak N-S oriented surface
warm front/trough was located in eastern PA heading east. A
moderately unstable airmass east of the frontal feature (MUCAPE 1000-
2000J/kg) was maintain a convective complex with showers and
embedded thunderstorms. This activity was generating 1-2.5" of
precipitation in central/east PA as it heads east, with rainfall
rates between 1-1.25" per hour per latest MRMS. The complex looks
to reach the CWA by about 0700-0800Z and should weaken as it does so
per SPC mesoanalysis, with a more stable environment as the complex
approaches.
Much of the day remains cloudy with the warm front hanging around,
which will limit overall airmass destabilization.
Second round of showers/thunderstorms associated with the
approaching shortwave and warm front are likely this afternoon.
Model soundings do show an appreciable increase in PWAT, with over
2" by this afternoon along with at least some increase in
instability (MUCAPE ~1000J/kg) and shear (0-6km shear values 25-
30kts) with the approaching shortwave. SPC maintains a marginal risk
of severe thunderstorms for the parts of area this afternoon as a
result. In addition, there is at least a localized flash flood
threat this afternoon with any thunderstorms given the high PWAT
environment. HREF probabilities of 3" in 3/hr are around 10%,
however, further supporting the localized nature of any flash
flooding.
Any convective activity should weaken as it heads east, given the
more stable environment and loss of upper support this evening.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
* Heat and humidity builds on Monday and continues into Tuesday.
Heat Advisory in effect for the entire area for both days.
Weak upper ridging aloft takes over for Monday and Tuesday as the
area continues to reside on the eastern edge of a large upper ridge.
An increase in heat and humidity on Monday as weak ridging builds
back in behind the departing shortwave. Dry weather is expected.
However, h850 temperatures approach 20-21C Monday afternoon with
dewpoint in the mid 70s (per NBM). Thus, heat indices of 100-105 for
northeast NJ and 95-100 elsewhere look possible once again Monday
afternoon.
More heat and humidity on Tuesday, under mainly dry conditions, as
the upper ridging begins to break down.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
The NBM was followed with no changes.
Key Points:
* Heat and humidity will continue on Wednesday. Widespread heat
index values between 95 and 99 with some locations reaching
the 100-104 mark. Heat headlines will be expanded into
Wednesday.
* Chances for showers and thunderstorms increases Wednesday into
Wednesday night as a cold front approaches and moves across the
region. Showers could persist into Thursday.
* High pressure returns to end the week and should dominate the
pattern this weekend bringing cooler temperatures and low humidity
levels.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
A weak warm front moves across the region today.
VFR/MVFR to start. MVFR conditions are a combination of haze and
smoke from wildfires and clouds moving in from the west. A
period of prevailing MVFR, with a low chance of IFR, will work
into the western terminals this morning and then across the
remainder of the area during the afternoon hours. Showers and
thunderstorms will move across the area terminals today.
Amendments may be needed to fine tune the timing of precip.
VFR conditions are then expected to return Sunday night as
drier low-level air filters in behind a surface trough.
S/SW winds today 5 to 10 kt. Tonight, winds become light and
variable.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments are likely for the timing of showers, possibly
thunderstorms, today. There looks to be multiple episodes or rounds.
Amendments are also likely for the timing of MVFR or lower
conditions today.
.OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...
Monday - Tuesday: VFR.
Wednesday: Mainly VFR. A chance of showers and thunderstorms
late in the day and at night.
Thursday: VFR. A chance of showers with MVFR possible.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
A weak pressure gradient thru Wednesday will lead to the
continuation of conditions below Small Craft Advisory levels.
Conditions should remain below Advisory levels next Thursday,
but there may be a slight increase in winds and seas due to the
passage of a cold front.
&&
.HYDROLOGY...
Isolated instances of flash flooding are possible this afternoon and
evening, mainly for NYC and points N&W. Rainfall rates of 2"/hr are
possible. There are currently no hydrologic concerns next
week.
&&
.TIDES/COASTAL FLOODING...
A low rip current risk overall is expected today and Monday
with any onshore swell component a bit weaker and a light
southerly wind wave Monday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Heat Advisory from 11 AM Monday to 8 PM EDT Tuesday for
CTZ005>012.
NY...Heat Advisory from 11 AM Monday to 8 PM EDT Tuesday for
NYZ067>075-078>081-176>179.
Air Quality Alert until midnight EDT tonight for NYZ067>075-
078>081-176>179.
NJ...Heat Advisory from 11 AM Monday to 8 PM EDT Tuesday for NJZ002-
004-006-103>108.
MARINE...None.
&&
$$
SYNOPSIS...BC/DBR
NEAR TERM...DBR
SHORT TERM...DBR
LONG TERM...
AVIATION...BC
MARINE...BC/DBR
HYDROLOGY...BC/DBR
TIDES/COASTAL FLOODING...