802
FXUS61 KALY 190603
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
203 AM EDT Thu Jun 19 2025

.SYNOPSIS...
Showers have generally diminished across the region, with some
patchy fog expected tonight. Dangerous heat and humidity
returns for tomorrow ahead of a strong cold front which could
result in strong to severe late afternoon thunderstorms with
damaging winds the main hazard. Confidence remains moderate to
high for dangerous heat to return early to mid next week.

&&

.NEAR TERM /THROUGH TODAY/...
Key Message:

- The Storm Prediction Center has maintained a slight risk
  (level 2 to 5) for severe weather tomorrow (mainly late
  afternoon into the early evening hours) as a potent cold
  front tracks eastward across the Northeast with damaging winds
  the primary hazard.

- The combination of hot temperatures and uncomfortable humidity
  on Thursday will lead to heat index values or the "feel- like
  temperatures" climbing into the mid to upper 90s, especially
  in the mid-Hudson Valley, Litchfield County, CT, into the
  Capital Region. A Heat Advisory for these areas (except
  Litchfield County) will go into effect at 11am Thursday and
  continue through 8pm.

Discussion:
.Update...As of 10:30 PM EDT...Most of the showers and storms
have diminished across our region, although a few showers/storms
are lingering south of Poughkeepsie near the I-84 corridor along
a remnant sfc convergence boundary. More widespread showers are
located over central NY and tracking eastwards, but with loss of
daytime heating and lack of large-scale forcing, we expect these
to mostly dissipate by the time they would reach out western
zones. Otherwise, mild and muggy tonight, with patchy fog
expected especially in areas that saw rain this evening. Other
than sky cover adjustments to reflect more clearing than
initially expected and a knocking temperatures down a couple
degrees in the areas that saw more clearing, previous forecast
remains in good shape with more details below...

.Previous...Our region remains downstream of an upper trough,
with a surface low well to the west, near the southern tip of
Lake Michigan. Deep SW flow out ahead of these features has
helped lift a warm front to the E/NE of our region per the
latest WPC surface analysis and obs...Storms/showers diminish
with the loss of daytime heating and we should trend drier
tonight. With a muggy air mass, temperatures will not cool much
only falling into the mid to upper 60s with cloudy skies
returning.

We remain concerned for both heat-related and severe weather
related impacts for Thursday. An intensifying shortwave trough
and deepening sfc low will advect an even warmer air mass into
the Northeast with 850 hPa isotherms +17C to +20C. Early clouds
quickly give way to morning sun and as southerly winds turn
rather breezy supporting deep boundary layer mixing. The
insolation and deep mixing should support temperatures rising
into the mid to upper 80s, topping out in the low 90s in the
immediate valley areas in the afternoon. WPC`s HeatRisk
continues to show much of our valley areas in its "moderate" or
level 2 categories as well. Between the heat and humidity, we
issued a Heat Advisory for the Hudson Valley from Albany to
Poughkeepsie for tomorrow afternoon.

An amplifying trough progressing out of the Great Lakes will
track into Ontario tomorrow afternoon, resulting in height falls
slowly spreading eastward into the Northeast. As the trough
takes on a neutral tilt, the sfc low deepens in eastern Ontario
and slows down. Overall timing for severe weather since
yesterday has trended later as the best forcing is now delayed
until after 18 UTC. With the main cold front now delayed until
closer to 00 UTC, storms that can develop head of the front
during the mid to later afternoon hours will likely favor storm
clusters or semi-discrete storm mode as strong southwest winds
aloft will result in rather strong deep layer shear values
around 35-45kts. Given the the hot/humid air mass ahead of the
front, the air mass will be primed for severe weather as sfc
based instability exceed 1000J/kg and mid-level lapse steepen
towards 5.5-6C/km. CAMs have trended less ambitious with very
little if any storm development until after 18 UTC which is
likely tied to weaker mid-level lapse rates and delayed arrival
of the trough/height falls. It may take until mid to later
afternoon for even discrete convection to initiate.


By 21 - 00 UTC, the main cold front starts approaching from the
west and straight line hodographs and shear vectors increasing
to 40-45kts, plenty of SB CAPE and shear vectors oriented
parallel to the forcing mechanism should support storm clusters
somewhat organizing into more of a line immediately ahead of the
main cold front. CAMs again are not overly enthused about a
classic squall line developing but ML guidance still show a
large swath of 15% damaging wind probabilities across the
Northeast tomorrow afternoon. Therefore damaging winds is the
primary hazard from any storms which matches with SPC`s
thinking but heavy downpours are also possible given the high
PWATs. Given the favorable set-up and strong forcing for
ascent, SPC maintains a slight risk (level 2 to 5) its Day 2
Convective Outlook over much of eastern NY and western New
England for Thursday. WPC has also blanketed much of the
Northeast in its "marginal risk" (level 1 of 4) for potential
localized flash flooding.

&&

.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/...
The trough axis/sfc cold front should finally push through the
region by Thursday evening with the trough taking on a negative
tilt allowing the sfc low to deepen towards ~995hPa. The front
is rather fast moving so the severe threat should end before
Midnight. Once the true cold front/trough axis sweep through by
the pre-dawn hours, winds quickly shift to the northwest and
even turn a bit breezy given the strong dynamics and subsidence
in its wake. Northwest winds advect a cooler and less humid air
into the region which will allow overnight lows fall into the
mid to upper 50s with low 60s in valley areas. Friday turns
quite breezy given strong subsidence in the wake of the
deepening low with northwest winds strengthening to 10-18mph
with gusts up to 30mph in the Mohawk Valley into the Capital
District and western MA. Probabilistic guidance even shows
25-40% chance for wind gusts to exceed 30mph. Otherwise, Friday
will be much more comfortable with lower humidity and seasonable
temperatures in the 70s to around 80 under plenty of sun.

High pressure builds overhead for Saturday giving us a pleasant
start to the weekend with much lower winds. As large scale
ridging from the Central CONUS builds into the Northeast, the
conveyor belt of strong westerly winds along its northern
periphery tracks overhead Sat afternoon resulting in partly
sunny skies. Temperatures also trend warmer and humidity levels
rise higher with highs back into the mid to upper 80s making it
uncomfortable once again. Luckily, not expect us to reach heat
advisory criteria. We continue to monitor the Saturday night
into early Sunday time frame for a potential "ridge roller" as
guidance continues to show a rather potent shortwaves riding
within the fast westerly flow aloft which could support
additional areas of showers/thunderstorms or even an MCS
(depending on the track). ML guidance has painted a 15%
damaging wind contour across the Upper Midwest/Great Lakes with
5% extending downwind into the Northeast. Where any MCS or storm
clusters develop will also depend on the overall track of the
shortwaves and the northern extent of the upper level ridging.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Key Messages:

- High confidence for a period of dangerous heat and humidity
  early to mid next week. There is greater than 75% confidence
  for temperatures to exceed 90 degrees Monday and Tuesday with
  even 45-50% confidence for high temperatures to reach or
  exceed 95 degrees in valley areas. Heat index values likely
  approach and even exceed 100 degrees Monday and Tuesday.


Discussion:

We remain focused on a prolonged period of hot and humid
weather Sunday through Tuesday as the large anti-cyclone (595 to
600dm 500hPa heights) from the Midwest/Ohio Valley builds
eastward with the hot air dome at its core extending into the
Northeast. Guidance remain in strong agreement for 700 and 850
hPa isotherms reaching 3.5 - 3 standard deviations above normal
per the NAEFS. Such high temperatures in the afternoon reaching
into the mid to even upper 90s combined with higher humidity
values will likely result in dangerous heat index values or
"feel- like" temperatures closer to 100 - 105 degrees. WPC
HeatRisk graphics show widespread "major" heat- related impacts
for Monday and Tuesday. Sensitive populations including the very
young, elderly, and those with pre-existing conditions should
limit time outdoors and avoid any strenuous outdoor activities.
Stay hydrated (even if you are not thirsty) and stay in air-
conditioning, if available. Overnight temperatures will not
provide relief as overnight lows only fall into the 70s in
valley areas (60s higher terrain) with high humidity continuing.
Visit weather.gov/heat for more preparedness information.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
Through 06z Friday...Despite a quiet scene depicted on latest
scans of the KENX radar, conditions across the terminals are
less than ideal due to low stratus clouds and patchy fog.
Therefore, IFR to MVFR ceiling thresholds are currently being
met almost everywhere with the exception being KPOU where LIFR
conditions currently hold due to fog.

Ceiling heights are anticipated to improve upon sunrise later
this morning, yielding the return to VFR conditions across all
TAF sites. Winds will become breezy out of the south today ahead
of an incoming frontal system and upper level disturbance
courtesy of deep mixing with sustained speeds of 10 to 12 kt
likely with gusts up to 20 to 25 kt. This afternoon, scattered
thunderstorms, some of which possibly becoming severe in nature,
will develop across the region. With differences in the model
guidance pertaining to the coverage and timing of convection,
there is still some uncertainty in this element of the forecast.
However, included TEMPOs and PROB30 groups to indicate the most
likely time of thunderstorms. Generally, the primary time period
looks to span 18z to 21z with the possibility of a secondary
round from 21 to 23z, but this is more likely at KGFL. Outside
of the threat for lightning, these thunderstorms will bring the
possibility for strong to locally damaging wind gusts.
Conditions during thunderstorms will likely vary between MVFR
and IFR.

Upon the conclusion of convection late this afternoon/early this
evening, conditions will improve back towards VFR thresholds.
Winds will shift in response to the passage of a cold front,
becoming southwesterly by this afternoon but maintaining a
similar magnitude of sustained and gust speeds that were seen
during the day today given the tighter pressure gradient
sprawled across the area as a result of the frontal system
passage.

Outlook...

Thursday Night: Moderate Operational Impact. Breezy. Chance of SHRA...TSRA.
Friday: Low Operational Impact. Breezy. NO SIG WX.
Friday Night: No Operational Impact. NO SIG WX.
Saturday: Low Operational Impact. Slight Chance of SHRA...TSRA.
Saturday Night: Moderate Operational Impact. Likely SHRA...TSRA.
Sunday: Low Operational Impact. Slight Chance of SHRA...TSRA.
Sunday Night: No Operational Impact. NO SIG WX.
Monday: No Operational Impact. NO SIG WX.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for NYZ052-053-059-060-064-065.
MA...None.
VT...None.

&&

$$

SYNOPSIS...Speciale
NEAR TERM...Main/Speciale
SHORT TERM...Speciale
LONG TERM...Speciale
AVIATION...Gant