Area Forecast Discussion
Issued by NWS Albany, NY
FXUS61 KALY 270115
Area Forecast Discussion
National Weather Service Albany NY
915 PM EDT Wed Apr 26 2017
As low pressure slowly departs, drizzle will end over the region
this evening into tonight, although it will remain fairly cloudy
with some patches of fog. Once clouds breaks on Thursday morning,
warm temperatures with a partly sunny sky are expected for Thursday
afternoon. A frontal boundary will bring some passing showers for
Thursday night, with another mild day expected on Friday.
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
As of 915 PM EDT...A stacked area of low pressure is situated
just southeast of the Long Island and is slowly drifting
The moist, cyclonic flow associated with the area of low
pressure will continue to keep it fairly cloudy throughout the
region into the overnight hours. Sky cover will generally be
mostly cloudy to overcast tonight. With the moist low levels,
some patches/areas of fog will be possible tonight, especially
in areas where the terrain traps the low-level moisture in
place, as surface temps cool off. With the clouds overnight,
temps will be in the upper 40s to mid 50s.
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
The closed off upper level low will continue to track away from
the area on Thursday, as it slides to the east of New England.
Meanwhile, a shortwave ridge will move across the area on
Once any morning fog and low clouds break up, skies should be
partly sunny and temperatures will be rather warm on Thursday
with dry conditions. Although 850 hpa temps will be warm and
reach 10 to 13 degrees C, mixing will be limited on Thursday to
about 875 hpa. As a result, max temps in valley areas look to
reach lower to middle 70s, with upper 60s for the high terrain.
The next storm system will be approaching for Thursday night
into Friday morning. The low pressure area will be well west of
the area and passing across the upper Great Lakes and into
western and central Ontario. Meanwhile, the surface cold front
will be approaching the area and running into the upper level
ridge, which will be causing it to weaken. A line of showers
will be along with this front, although they will be diminishing
in coverage and intensity. Have generally gone with chc pops
for Thursday night into early Friday for showers. Some isolated
thunderstorms will be possible as well. Although surface-based
instability looks fairly limited, there could be some elevated
instability in place, so a few rumbles of thunder will be
possible along with some of the rain showers. Lows on Thursday
night look to fall into the 50s.
The front should be through early in the day, allowing for
clearing to occur on Friday morning. Despite being behind the
front, this clearing will allow for another mild day on Friday
afternoon with highs in the upper 60s to upper 70s, with dry
After dry weather on Friday evening, a slight chance for showers
will return by late Friday night as the next frontal system
starts to approach with increasing cloud cover. Lows on Friday
night will once again mainly be in the 50s.
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
The extended forecast period continues to be a bit unsettled as
multiple frontal boundaries impact the region this weekend into the
early next week.
Saturday will feature Canadian high pressure slowly sinking into far
Upstate NY with an east-west oriented frontal boundary stalled over
the Capital District Valley. A notable 850mb temperature spread
results across the front with +12-14C in Dutchess and Ulster while
+4-6C sits over Herkimer and Hamilton Counties. This makes for a
tricky and lower confidence temperature forecast as highs will be
contingent on exact frontal placement. For now have gone with
low 80s in the mid - Hudson Valley cooling down to mid 60s for
our northwest CWA. Temperatures are not the only parameter
impacted by the front. Most models suggest an impulse riding
along the boundary between 18z and 00z Saturday which results in
rain and possible t-storms. The 12z NAM, Canadian and GFS are
fairly in line with the boundary stalling across the Capital
District while the ECMWF is an outlier having the front sag
further south into the mid - Hudson Valley. Any isolated to
scattered showers/storms should end quickly Sat night as the
cold front pushes south of our CWA and the Canadian surface high
takes control. This high will usher in cooler temperatures with
overnight lows falling into the 40s with even a few 30s popping
up over the Adirondack Park and southern Greens.
With high pressure in place, Sunday will be fairly pleasant overall
as H500 ridge takes shape off the Mid Atlantic Coast. Clouds will be
on the increase from the west/southwest during the afternoon with a
chance of showers (best chance west of the Hudson River Valley) as
the front from Saturday begins to retreat north as a warm front.
There is also a slight chc of thunderstorms due to weak
elevated instability. Better chances of showers Sunday night with
the warm front setting up just south and west of the forecast area
over PA. Considering the isentropic lift and moisture convergence, the
boundary may continue the showers into Monday morning. Highs on
Sunday will generally be in the mid and upper 60s in the valley
areas, and upper 50s to mid 60s over the hills and mountains. Lows
Sunday night due to wet bulbing will be in the 40s to lower 50s.
Monday into Tuesday...Some uncertainty with the forecast on Monday,
as a strong sfc cyclone moves into the Upper Midwest and western
Great Lakes Region. The warm front placement is variable in the
deterministic and ensemble guidance. A blend of the guidance
favored high chc/low likely pops for most of the region with a
chance of afternoon thunderstorms if we get into a warm sector ahead
of the cold front. Modest amounts of instability are forecasted by
the latest 00Z GFS. Sfc dewpts do get into the 50s. The best
convergence with the cold front looks to be late Monday afternoon
into the nighttime period, so we continued high chc and likely pops
for showers and a slight/low chc of thunderstorms. Highs Monday
were lowered some due to the rain cooled air and clouds possibly
lingering with 60s to lower 70s, as lows will only fall back into
the mid 40s to mid 50s. The cold front drifts south of the region
Tuesday, but a short-wave pivoting around the H500 upper low south
of James Bay way focus some isolated to scattered showers, as temps
trend back to seasonal normals with highs in the 50s to lower 60s
over the higher terrain, and mid and upper 60s in the valleys.
.AVIATION /01Z THURSDAY THROUGH MONDAY/...
This evening mainly clear skies were located across northern
areas with more solid cloud cover around KPOU and KPSF.
For this evening clouds will reform over the region as some
subsidence traps low level moisture. So, MVFR ceilings at all
TAF sites with trends toward IFR after midnight, especially at
KPSF and KPOU. Some fog could also form especially at KPOU and
KPSF. Some breaks in the clouds and some radiational cooling
will allow for IFR visibilities at most of the TAF sites
After 13Z-15Z Thursday KGFL and KALB will see ceilings lift just
above 3000 feet but KPOU and KPSF maybe slower to lift through MVFR
levels. Visibilities should be P6SM at all sites after 13Z-15Z
Winds will be light north to east at 6 Kt or less this evening,
then nearly calm tonight. Winds become light southeast to south
at 6 Kt or less Thursday morning.
Thursday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Friday: Low Operational Impact. Slight Chance of SHRA...TSRA.
Friday Night: Low Operational Impact. Slight Chance of SHRA.
Saturday: Moderate Operational Impact. Chance of SHRA...TSRA.
Saturday Night: Low Operational Impact. Slight Chance of SHRA.
Sunday: Moderate Operational Impact. Chance of SHRA.
Sunday Night: Moderate Operational Impact. Chance of SHRA.
Monday: Moderate Operational Impact. Chance of SHRA...TSRA.
Cloudy and damp weather will continue into tonight. However, it
should dry out on Thursday with partial sunshine by afternoon.
RH values will fall to 50 to 60 percent on Thursday afternoon
with south winds of 5 to 10 mph. After some passing showers on
Thursday night, dry weather will return again during the day on
Friday. RH values will fall to 45 to 55 percent on Friday
afternoon with west to southwest winds of 5 to 10 mph.
As a coastal low finally departs, any lingering drizzle will
end this evening. After dry weather on Thursday, some passing
light rain showers are possible for Thursday night into Friday
morning. QPF amounts will be fairly light with this system,
mainly under a quarter of an inch. Another period of dry
weather is expected for Friday afternoon into Friday night,
before another frontal system moves across the area on Saturday.
QPF amounts will be variable with this front due to the
convective nature of the precipitation. More showers and
possible thunderstorms are possible again Monday into Monday
night with yet another frontal boundary as well.
For details on specific area rivers and lakes, including observed
and forecast river stages and lake elevations, please visit the
Advanced Hydrologic Prediction Service /AHPS/ graphs on our