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Area forecast discussion 
National Weather Service Albany New York
655 PM EDT Wednesday Jul 23 2014

Synopsis...
a cold front has crossed into the capital region. Cooler air a few
lingering showers were behind the cold front...while strong to
possibly severe thunderstorms could still form south and east of the
capital region until 10 PM. After that...showers will persist to the
southeast of the capital region...with drier air filtering into the
whole region by Thursday. Thursday through Saturday should be dry
with comfortable levels of humidity.

&&

Near term /until 6 am Thursday morning/...
as of 655 PM EDT...the Severe Thunderstorm Watch has been cancelled
from the capital region and areas north and west of Albany. Laps
analysis indicated that the instability has been knocked down to
less than a 1000 j/kg in this area. Radar trends have weakened
considerably. Should only have mainly scattered showers...tapering
to isolated showers northwest of the capital region...with little if
any thunder happening.

There was still over 2000 j/kg well southeast of the capital
region...so a Severe Thunderstorm Watch continues in those areas
until 1000 PM. There was a broken line of thunderstorms working
through this area...and any of these could briefly become severe.

Temperatures have dropped into the 70s from the capital region north
and west as thunderstorms...and the cold front...have worked through
the region.

The upper level dynamics of the system will lag behind...as the
right rear entrance region of an upper level jet works into our
region overnight. This could allow for showers to linger behind the
cold front...and there might even be a weak surface wave working
along the front as well. Will keep likely probability of precipitation for showers only (as
the instability should diminish by then).

Temperatures will cool into the 60s overnight from Albany
southward...50s well north and west. Dewpoints will drop into the
50s...and even some upper 40s northwest.

&&

Short term /6 am Thursday morning through Saturday/...
any lingering showers in our extreme southeastern zones should exit
shortly after daybreak Thursday. Otherwise...a noticeably drier and
cooler airmass will infiltrate our region on Thursday. Clouds will
slowly break up from northwest to southeast.

H850 temperatures will cool from the upper teens celsius from late
today...to around +10c on Thursday. This will translate to high
temperatures on Thursday to be about 10 degrees lower compared to
today...generally around 80 in the valleys...lower to middle 70s higher
terrain. Dewpoints will generally be in the 50s...so comfortable
level of humidity.

High pressure will build to our south from Canada Thursday night
through early Saturday.

Thursday night will be mainly clear calm and cool with lows dipping
down to the lower to middle 50s Albany southward...40s well north and
west of Albany. Patchy fog will form in the fog-prone areas
(generally low lying areas near bodies of water).

Friday will see sunshine mixing with fair weather cumulus clouds.
High temperatures will be similar to Thursday. Dewpoints will remain
in the 50s.

Mainly clear with lows in the 50s Albany southward...40s north.

Saturday should be dry...but high clouds from a disturbance and warm
air advection will mean an increase in high clouds. Dewpoints will
creep up to around 60...so a little more humid but but still at
moderate levels.

&&

Long term /Saturday night through Wednesday/...
a large middle level trough will dig to our west across the Great Lakes
and Ohio Valley...and remain there must of the extended period as an
upper level low is forecast to develop across eastern Canada.

The initial vorticity (mid level energy) associated with the trough
will approach our region with an associated surface low and warm air
advection...will work into our region from west to east late
Saturday night and Sunday. This is a little faster than previous
guidance indicated. A threat of showers will increase as we head
toward Sunday. Although surface instability might be limited...there
could be plenty of elevated convection aloft...so will mention
thunder as well.

This initial surge of energy will move on by on Monday...however our
region will remain under a cyclonic flow with lingering low level
moisture on Monday. We will continue with chances of showers and
thunderstorms on Monday although that day will probably offer some
dry time.

The trough/upper air low will slowly weaken with time...but not go
away through Wednesday. There are indications additional middle level
drying should decrease the threat of showers and thunderstorms
Tuesday and especially Wednesday. However...we are talking about a
cutoff low...and certainly...there could additional disturbance (not
depicted at this time)...could produce additional bouts of showers
and thunderstorms.

We will keep a 30 percent chance of showers and afternoon
thunderstorms on Tuesday and for now...just a slight chance of
showers on Wednesday.

Temperatures during the extended will trend slightly below normal as
the trough pulls some slightly cooler air from Canada.

However...it will be moderated through a southwesterly low. Look for
highs generally around 80 in the valleys...70s higher terrain.

Lows will in the 60s Saturday through Monday nights...cooling to the
50s around 60 Tuesday night.

&&

Aviation /00z Thursday through Monday/...
a Severe Thunderstorm Watch is in effect for all the taf sites
through 02z. The potential is there for thunderstorms to produce
wind gusts to 50kts and hail an inch in diameter or more. In
addition any thunderstorm could contain very heavy rainfall and
frequent cloud to ground lightning.

As of 21z...a line of storm backbuilded from northeast to southwest
almost to the Albany international Airport. More thunderstorms were
in Schoharie County tracking northwest. Placed a thunderstorms in the vicinity in the Albany
taf through 00z...with a tempo for MVFR reduced rain and wind gusts
to 30kts.

Thunderstorms were impacting kgfl but temperatures there had dropped
into the 70s...lowering the threat of additional storms.

Thunderstorms were working toward the Pittsfield Airport as well as
kpou. Both should be impacted by storms within the hour. Have thunderstorms in the vicinity
in both tafs...and occasional reductions at least to MVFR (could
easily drop briefly to ifr) due to heavy rainfall. Wind gusts could
reach 25kts or better.

Once the thunderstorms end...keeping vcsh for a few hours for
lingering activity...but longer...through about 09z at kpou since
the front may slow its progress in southern areas. Some fog may
form after some clearing at kgfl...kalb and kpsf toward daybreak but
only indicating 6sm br until we can analyze short term trends behind
the front after sunset.

After sunrise tomorrow...VFR everywhere...but will have to see if
any showers linger around kpou after 09z if the progress of the
front slows.

South to southwest winds this afternoon at 10 knots or less could be
variable and gusty to 25 knots or more in thunderstorms. The winds
should shift to west and northwest by this evening at less than 10
knots...the diminish to less than 6 knots and trend toward north.
Tomorrow morning...winds should be north northwest to north
northeast at less than 10 knots.

Outlook...

Thursday night: no operational impact. No sig weather.
Friday: no operational impact. No sig weather.
Friday night: no operational impact. No sig weather.
Saturday: no operational impact. No sig weather.
Saturday night: low operational impact. Slight chance of rain showers.
Sunday through monday: moderate operational impact. Chance of
rain showers...tsra.

&&

Fire weather...
showers and thunderstorms will move across the region through
evening along and ahead of a cold front. Most areas should receive a
quarter inch or more through early Thursday. Showers could linger
south and east of Albany into early Thursday.

Otherwise...it will turn less humid on Thursday with increasing
afternoon sunshine. Dry pleasant weather will prevail through
Saturday with the formation of dew each night.

Relative humidity values will dip to the 40s on Thursday afternoon...mainly 30s
Friday afternoon...and 40s Saturday afternoon.

The next chance of showers and thunderstorms will be late Saturday
night through at least Monday.

The surface wind will be south 5 to 15 miles per hour...gusting to 25 miles per hour
tonight (possibly a lot higher in and near thunderstorms). The wind
will shift to north or northwest 5 to 15 miles per hour tomorrow and Friday.

&&

Hydrology...
numerous showers and thunderstorms will work across our region this
evening...with lingering showers possible overnight south and east
of Albany. Average basin rainfall looks to be over 0.25
inches...with localized amounts up to two inches possible a few of
thunderstorms (or training thunderstorms). Precipitable waters associated with
this airmass will approach two inches this evening...before falling
off later overnight and especially on Thursday.

The heavy rainfall could cause localized ponding of water on low
lying areas and poor drainage area. Will continue enhanced wording
for heavy rainfall through this evening.

With the passage of the cold front...a cooler and less humid air
will be ushered in. Expected some lingering showers into Thursday
morning as the front will be slow to move off to the east. Then
looking at dry weather into at least the first half of the weekend.
The weather will turn unsettled as we head into the second half of
the weekend and into next week.

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...hwjiv
near term...hwjiv
short term...hwjiv/bgm
long term...hwjiv
aviation...hwjiv/NAS
fire weather...hwjiv
hydrology...hwjiv

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