944
FXUS61 KALY 111739
AFDALY

AREA FORECAST DISCUSSION
National Weather Service Albany NY
139 PM EDT Sat May 11 2024

.SYNOPSIS...
An upper level low will bring some rain showers to the region
into Sunday morning before gradually tapering off later in the
day. Cool conditions continue through the rest of the weekend
with more seasonable weather returning for next week. Rain
chances continue through the early to the middle part of next
week with a trend toward drier weather by late week.

&&

.NEAR TERM /THROUGH TONIGHT/...
.UPDATE...As of 120 PM EDT, a negatively tilted upper-level low
is continuing to approach from the Great Lakes. Weak instability
has developed with latest SPC mesoscale analysis showing 100-300
J/kg of SBCAPE across portions of the region. This is resulting
in an increase in diurnal cumulus clouds with pop up showers
also increasing in coverage. Best coverage of showers at this
time are for areas west of the Hudson River. Expect mostly
cloudy conditions through the afternoon with some scattered
showers around at times. The 12z KALY sounding shows a
pronounced inversion around 600 hPa which is likely the maximum
level/height that these showers can grow in the vertical. With
the expected shallow nature of these showers, thunder is
unlikely but any taller showers that could grow above this level
could produce some pea size hail. Highs today will run a few
degrees below normal ranging from the 50s across the higher
elevations to the lower to mid-60s in the valleys.

Showers will continue through tonight as the core of the upper
low crosses the region into Sunday morning. Lows will fall
mainly into the 40s with some upper 30s across the higher
elevations.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
The upper low will pass overhead and continue eastward over New
England on Mother`s Day. Resulting showers may linger into the
morning on the western flank of the circulation, however
coverage will decrease into the afternoon as the feature
continues eastward over the Gulf of Maine. A brief dry break
will then last through Sunday night as heights rise aloft behind
the upper low. Temperatures remain cool beneath the upper low,
with afternoon highs only reaching the upper 40s to low 50s in
high terrain and mid to upper 50s at lower elevations, and
overnight lows dipping into the mid 30s to mid 40s across the
region.

As upper ridging flattens over the region, a warm front will
approach from the west on Monday, bringing increasing chances
for rain showers into the afternoon. Temperatures will moderate
as mid-level flow shifts out of the southwest behind the
boundary, with temperatures reaching afternoon highs in the mid
to upper 50s in high terrain and low to mid 60s at lower
elevations. Increased cloud cover overnight will aid in keeping
temperatures mild, as overnight lows only fall to the upper 40s
to mid 50s across the region.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
We start the long term off with a weak surface low tracking through
Quebec near the Hudson Bay and its attendant cold front approaches
the Northeast. Southerly flow ahead of the boundary ushers in a
warmer air mass allowing temperatures on Tuesday to warm towards 70
which is right around the climatological norm. Meanwhile, in the
Ohio Valley we will be monitoring an initially open trough. As the
trough shifts eastward, southwesterly winds along and ahead of our
cold front will strengthen, enhancing the moisture
advection/convergence along the boundary. In fact, PWATs rise above
1" making it feel rather humid on Tuesday. The increased moisture
convergence plus height falls ahead of the wave will likely result
in areas of showers along and ahead of the cold front which is why
we maintained widespread likely POPs for Tuesday into Tuesday night.
The increased humidity will also keep a slight chance for
thunderstorms. Guidance suggests an inverted trough develops along
the boundary given this set-up and with enhanced PWATs, periods of
steady rain look possible.

Recent trends indicate that our initially open wave in the Ohio
Valley may close off which would prolong precipitation into
Wednesday. There are still discrepancies among the guidance if this
wave remains open or closes off/slows down but with the trough in
the left exit region of a jet streak, we decided to account for
recent pessimistic trends and linger chance POPs through the day
Wednesday. In fact, the trough may even linger into Thursday if it
closes off based on some latest trends but we maintained a dry
forecast until there is more of a consensus.

Once the trough/closed low finally exits, there should be a brief
dry respite as high pressure builds in behind it with a warm air
mass continuing overhead. This should support near to even warmer
than normal temperatures once high pressure takes control. However,
the dry break is short-lived as our next boundary looks to arrive
for the weekend.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
Through 18z Sunday...VFR conditions in place to start this
afternoon, with increasing mid level clouds. Showers will also
increase in coverage as an upper level low moves in from the
west. Brief MVFR conditions are possible with some of the SHRA,
but not a great enough chance to mention in the first 6-9
hours. Expecting mainly scattered coverage for much of the 24
hour TAF period, so will include VCSH initially, then PROB30
from overnight into Sunday morning. Conditions (mainly cigs)
will likely lower to MVFR levels towards early Sunday morning,
then should remain MVFR through 18z.

Winds will be south-southeast around 5-10 kt through 18z Sunday.
Occasional gusts to 15 kt will be possible at KALB.

Outlook...

Sunday Night: No Operational Impact. NO SIG WX.
Monday: Moderate Operational Impact. Chance of SHRA.
Monday Night: Moderate Operational Impact. Chance of SHRA.
Tuesday: High Operational Impact. Likely SHRA...TSRA.
Tuesday Night: High Operational Impact. Likely SHRA...TSRA.
Wednesday: Moderate Operational Impact. Chance of SHRA...TSRA.
Wednesday Night: Low Operational Impact. Slight Chance of SHRA.

&&

.ALY WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
MA...None.
VT...None.

&&

$$

SYNOPSIS...Rathbun
NEAR TERM...Rathbun
SHORT TERM...Picard
LONG TERM...Speciale
AVIATION...JPV