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fxus61 kaly 230918 
afdaly

Area forecast discussion
National Weather Service Albany New York
518 am EDT Tue may 23 2017

Synopsis...
a ridge of high pressure will dominate our weather through Wednesday
with fair weather and seasonable temperatures. The weather will turn
unsettled for the latter part of the week as a slow moving low
pressure system approaches and moves across the region bringing a
widespread rainfall to the area.

&&

Near term /until 6 PM this evening/...
for today high pressure will build across our region resulting
in partly to mostly sunny skies once any early morning fog
Burns off. It will be a seasonable day with highs in the mid 60s
to mid 70s and a west wind around 5 mph.

&&

Short term /6 PM this evening through 6 PM Wednesday/...
a storm will pass well south and east of the region tonight and
Wednesday as high pressure continues to control our weather.
There may be a few more clouds tonight along with patchy fog and
lows in the mid 40s to mid 50s.

Skies are expected to be mostly sunny on Wednesday although
clouds may increase some late in the day as a stationary front
will be anchored north of the Saint Lawrence River valley with
an area of low pressure moving into the Ohio Valley. Highs will
be in the upper 60s to upper 70s.

&&

Long term /Wednesday night through Monday/...
unsettled conditions are expected through much of the long term
portion of the forecast, as one closed low affects the region
Thursday through Friday, followed by the approach of a potentially
slow moving frontal system for Sunday into Monday. In between
systems, there could be a few opportunities for relatively
dry/tranquil conditions, but exact timing of these will likely
change as we approach the end of the week.

For Wednesday night-Friday, 00z/23 global deterministic models and
their ensembles continue to suggest a closed low forming somewhere
over the Tennessee/lower Ohio Valley before slowly translating northeast
toward the northern mid Atlantic coast and eventually across or just
south of southern New England by late Thursday into Friday. There
are some suggestions in the guidance that an initial surge of warm
advection precipitation may develop and pass from NYC/Li into
southeast New England for Thursday, while additional heavier rain
occurs across western PA/New York closer to the main upper level energy,
before eventually consolidating into one general area of moderate to
locally heavy rain for Thursday night into a portion of Friday. At
this time, have suggested increasing pops from south to north
Thursday morning, with likely or higher pops by afternoon through
Friday morning. Precipitation could become more spotty Friday
afternoon, especially across southern areas as wrap around
precipitation lifts northeast.

Temperatures should remain below normal due to clouds and showers
through the period, especially for daytime highs. Expect mainly 50s
and lower 60s Thursday, with upper 50s to lower/mid 60s Friday.
Overnight lows will mainly be in the upper 40s to lower 50s.

Some shortwave ridging may develop and translate across the region
sometime Friday night into Saturday night, and will indicate a break
in the showers at this time. Some models suggest a weak frontal
system may approach from the north Saturday afternoon, possibly
triggering some showers across the Adirondacks, but for now, have
only indicated some slight chance pops in this area. Highs should be
warmer assuming no rain and some breaks of sun, with forecast highs
in the lower/mid 70s in valleys, and 60s across higher elevations.

Then for Sunday-Monday, models suggest another impulse approaching
from the west, with a warm advection regime developing Sunday or
Sunday night. This should bring another round of showers, but exact
timing is uncertain, as it could hold off until later in the day or
at night. Have suggested highest pops later in the day into Sunday
night. Highs Sunday are currently forecast to reach the mid 60s to
lower 70s, although if showers hold off until later in the day,
slightly warmer Max temps could occur. Sunday night lows should be
mainly in the 50s.

Then on Monday, there remain timing differences as to the speed of a
cold/occluded front moving east across the region. Have indicated
chance pops, but again, at this time range, there remains some
uncertainty, as a faster moving frontal system could bring some
drying to at least portions of the region later in the day. Highs
should mainly be in the mid 60s to lower 70s, but could be warmer if
rain tapers off earlier.

&&

Aviation /09z Tuesday through Saturday/...
some clearing has made its way into the region, allowing for
some of the lower clouds to clear out. However, some radiational
fog has developed especially at kpou which may keep IFR
conditions for early this morning. Any morning mist or low
clouds should quickly dissipate after sunrise due to the strong
late may sunshine. VFR conditions are expected through the
entire day today with just some passing high cirrus clouds
which will linger into the evening and light west to northwest
winds at 5 kts or less. There is the potential for some fog
again tonight especially at kgfl and kpou with IFR conditions
possible.

Outlook...

Wednesday night: low operational impact. Slight chance of rain showers.
Thursday: high operational impact. Likely rain showers.
Thursday night: high operational impact. Likely rain showers.
Friday: high operational impact. Likely rain showers.
Friday night: no operational impact. No sig weather.
Saturday: no operational impact. No sig weather.

&&

Fire weather...
a ridge of high pressure will dominate our weather through Wednesday
with fair weather and seasonable temperatures. The weather will turn
unsettled for the latter part of the week as a slow moving low
pressure system approaches and moves across the region bringing a
widespread rainfall to the area.

Relative humidity values will drop to 35 to 50 percent today,
recover to 85 to 100 percent tonight, and drop to 35 to 50
percent again on Wednesday.

Winds will be west around 5 mph today, north to northwest around
5 mph tonight, and southeast around 5 mph on Wednesday.

&&

Hydrology...
a ridge of high pressure will dominate our weather through Wednesday
with fair weather and seasonable temperatures. The weather will turn
unsettled for the latter part of the week as a slow moving low
pressure system approaches and moves across the region bringing a
widespread rainfall to the area.

Significant rainfall is expected during the later part of the
week into the weekend with a total of several inches of rain
possible through Monday. This may result in significant within
bank rises on area streams and rivers as well as ponding of
water on roadways.

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...none.
Massachusetts...none.
Vermont...none.

&&

$$
Synopsis...iaa/11
near term...11

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