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fxus61 kaly 181954 
afdaly

Area forecast discussion
National Weather Service Albany New York
354 PM EDT Wed Sep 18 2019

Synopsis...
high pressure will remain in control of our weather, providing
plenty of sunshine and cooler than normal temperatures through
Thursday. Temperatures will begin moderating to above normal
levels Friday into the weekend with dry weather continuing as
the high drifts into the southeastern United States.

&&

Near term /through Thursday/...
as of 330 PM EDT, high pressure remains in control of our
sensible weather resulting in mostly clear skies and slightly
below normal temperatures. This trend will continue through
Thursday as the surface ridge gradually shifts southwestward.

Overnight temps will be the coldest of the week due to optimal
radiational cooling conditions, with lows falling into the 30s
and low 40s. There is a frost advisory from 3 am to 8 am for
the southwest Adirondacks, Lake George/Saratoga region, southern
Vermont and Berkshires where low temperatures will be in the low to
mid 30s. Fog is also expected to develop overnight, especially
in the river valleys where it could become locally dense prior
to daybreak.

Thursday will be much like today with highs near 70 and mostly
sunny skies.

&&

Short term /Thursday night through Saturday/...
the upper level ridge continues to build into the region
Thursday night as tc Humberto pushes further eastward into the
Atlantic. At the same time, the surface ridge continues to slide
southwest. This will result in slight moderation of temperatures
a some scattered clouds. Overnight lows will be milder, in the
mid to upper 40s.

Friday into Saturday, the surface ridge centers itself over the
southeast Continental U.S. As the upper ridge centers itself over the Ohio
Valley. This will lead to above normal warmth both days with
highs in the mid 70s to low 80s. The normal high for Albany this
time of year is 72 degrees. Friday night lows will be even
milder and may not even dip below 50 degrees. There will be a
mix of sun and clouds both days but the weather will remain dry.

&&

Long term /Saturday night through Wednesday/...
the period starts out Saturday night with our region still under the
influence of an upper level ridge along the East Coast, however the
500 mb ridge axis is expected to shift east off the coast by Sunday.
So it will still be dry and mild Saturday night, and likely through
Sunday as well based the 12z GFS/ECMWF/CMC. With the ridge off the
coast, this will allow for a warm S-SW flow to occur on Sunday with
an already anomalously warm (+1 to +2 stdev at 850 mb) air mass in
place. Surface temperatures will be well above normal as a result,
possible by as much as 10-15 degrees.

Chances for showers will gradually increase from northwest to southeast across the
area Sunday night into Monday, as a cold front moves through.
However, there are timing/strength differences with regards to the
upper level pattern among the guidance through the rest of the
period. The European model (ecmwf) is indicating a stronger/deeper trough, which
takes through Tuesday to pass through. The GFS is depicting a more
de-amplified trough and much more progressive. So there is a low
confidence in probability of rain forecast in any given period
during the early to the middle part of next week. The GFS has rain
returning by Wednesday with a fast-moving wave approaching, however
the European model (ecmwf) is dry with a surface ridge in place. Temperatures should
gradually cool back to slightly above normal levels by Tue/Wed once
the front passes through.

&&

Aviation /20z Wednesday through Monday/...
skies are sct for the valley sites of kgfl, kalb and kpou and
bkn at kpsf, thanks to some flat cu on the backside of a
departing upper level shortwave. As the shortwave continues to
depart, these clouds will dissipate by this evening, allowing
for clear skies tonight. North to northeast winds will be 5 to
10 kts through the rest of the day, but should start to become
very light or calm this evening with the loss of daytime
heating/mixing.

Good radiational cooling will be in place tonight with clear
skies and light/calm winds. This should allow some radiational
fog to form at kgfl by midnight, with IFR conditions expected
there for the rest of the night. Some fog could form at kpsf as
well, although it may take until closer to sunrise. Not too
confident on if any fog will form at kalb/kpou due to such a dry
air mass in place. Will continue to evaluate and if it does
occur, it would probably be in a short window right around
sunrise.

After sunrise Thursday, any radiational fog will dissipate,
allowing for VFR conditions and clear skies for the entire day.
Winds will be very light and variable for Thursday at all sites.

Outlook...

Thursday night-sunday: patchy fog possible late each night/early
morning, otherwise no significant weather.
Monday: low operational impact. Chance of showers.

&&

Fire weather...
high pressure will remain in control of our weather, providing
plenty of sunshine and cooler than normal temperatures through
Thursday. Temperatures will begin moderating to above normal
levels Friday into the weekend with dry weather continuing as
the high drifts into the southeastern United States.

Relative humidity will recover to 90-100 percent tonight with widespread dew
formation and some areas of frost expected. Relative humidity will fall to
30-50 percent Thursday afternoon, lowest within portions of the
Hudson River valley from Albany south to Poughkeepsie and across
the southwest Adirondacks.

Winds will become light/variable at less than 5 mph shortly
after sunset and continue overnight into Thursday.

&&

Hydrology...
no Hydro problems are expected in the Albany Hydro service area
/hsa/ through at least Sunday.

There are some abnormally dry areas in the aly hsa based on the
most recent drought monitor, and there is a high probability of
dry weather through at least Sunday.

The next chance of widespread rainfall may be with a cold
frontal boundary approaching on Monday.

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 website.

&&

Aly watches/warnings/advisories...
CT...none.
New York...frost advisory from 3 am to 8 am EDT Thursday for nyz032-033-
041>043-054-083-084.
Massachusetts...frost advisory from 3 am to 8 am EDT Thursday for maz001-025.
Vermont...frost advisory from 3 am to 8 am EDT Thursday for vtz013>015.

&&

$$
Synopsis...jlv
near term...jlv
short term...jlv

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