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Area forecast discussion 
National Weather Service Albany New York
320 PM EDT Wednesday Jul 1 2015

Synopsis...
a cold front will cross the region this evening bringing scattered
showers and thunderstorms. Behind this front...drier weather will
take hold as a fairly large high pressure area builds tomorrow
through the beginning of the Holiday weekend.

&&

Near term /until 6 am Thursday morning/...
as of 320 PM EDT...a line of showers and thunderstorms was
working across the Mohawk Valley about to reach the capital
region. These were ahead of cold front and short wave working
through the region.

These showers will work steadily across the region through the
afternoon hours.

One of the storms was marginally severe as it worked through
Johnstown knocking a few trees and wires down in that town.

Drier air working in aloft might help any thunderstorm that does
form to enhanced the transport momentum of strong winds
aloft. So there it is still potential that thunderstorms could
produce gusty winds and a least some hail as sbcapes were over
1000 j/kg and middle level rates were around 6.5c/km. The 0-6km bulk
shear was about 35kts.

All these parameters are marginal for severe...so Storm Prediction Center/S marginal
severe thunderstorm looks reasonable for the remainder of this
afternoon.

Fortunately...the flow is progressive...so we are not looking for
any flash flooding issues.

High temperatures this afternoon will reach 80-85 in the Hudson
Valley from Albany southward...before the showers and front work
through...middle to upper 70s most other places.

A south to southwest wind will become west
to northwest behind the cold front by late this afternoon...with
gusts up to 25 miles per hour at times.

Tonight...as the cold front and short wave moves buy...any
lingering showers and thunderstorms south and east of Albany look
to end fairly quickly. Then...drier air will begin filtering in.
The sky will remain partly cloudy.

H850 temperatures will drop to about +6 in our northern
zones...closer to +10c in our southeast areas. A breeze will
linger across the higher elevations/Mohawk Valley and capital
region. Look for lows generally in the 50s overnight...except
locally around 60 in the capital region.

&&

Short term /6 am Thursday morning through Saturday/...
high pressure will be in control of our weather through this
period...brining a couple days of dry and pleasantly warm weather
as we head to the early part of the Holiday weekend.

H850 temperatures will average close to +10c. This will yield to
slightly below normal high temperatures reaching 75 to 80 in the
valleys...70-75 higher terrain.

Under a mainly clear sky...light or no wind...temperatures will
cool on both Thursday and Friday night. Look for lows down into
the middle to upper 40s areas well north of the capital regions...and
sheltered mountain valleys even into the Catskills. There could be
some colder pockets bottoming out close to 40. Lows will be in
the lower to middle 50s in the Hudson and Mohawk valleys from Albany
southward.

There will be few-scattered cumulus forming in the valleys each afternoon...and
scattered-broken cumulus across the higher terrain. At worst...there could be a
afternoon mountain sprinkle...but otherwise it will be dry. A
northwest wind will average 10-15 miles per hour...gusting to 25 miles per hour across
the higher terrain/Mohawk Valley and the capital region on
Thursday. On Friday with high pressure overhead...the wind
variable generally under 10 miles per hour.

&&

Long term /Saturday night through Wednesday/...
it appears that rising
middle/upper tropospheric heights and surface high pressure will be the
main highlights during this portion of the forecast...although
subtle smaller scale disturbances will still need to be
watched...especially on Saturday.

For Sat-Sat nt...there are still some hints that a northern stream
impulse may interact with some moisture from the south...leading to
at least few afternoon/evening showers and thunderstorms. Will keep
low chance probability of precipitation for most areas Sat afternoon-evening for scattered
showers/isolated thunderstorms...although future forecasts may still
continue to trend more optimistic if forecast models suggest less
interaction between impulses/moisture. Temperatures should be near
normal...mainly in the upper 70s to lower 80s in valleys...and
Lower/Middle 70s for higher elevations for highs...and middle 50s to
around 60 for Sat nt/sun am mins.

Sun-Monday nt...it appears that in the wake of any potential upper
level disturbance passage...high pressure and rising middle/upper level
heights should return for sun-Mon. This should allow for generally
fair weather...with temperatures returning to more seasonable levels...with
maximum temperatures in the Lower/Middle 80s in valleys and 75-80 across higher
elevations...and overnight mins ranging from the middle 50s across
higher elevations...to the Lower/Middle 60s in valleys.

Tuesday...the next front may approach by later in the day or at night.
Have included mention of chance probability of precipitation for showers/thunderstorms. Temperatures
should reach the Lower/Middle 80s across lower elevations and 75-80
across higher terrain.

&&

Aviation /19z Wednesday through Monday/...
flying conditions have generally improved to VFR for all
sites...although brief periods of MVFR ceilings due to lingering low
stratus cannot be ruled out through the afternoon hours.

An upper level disturbance and associated surface cold front is
allowing for some showers and isolated thunderstorms over the region
this afternoon. This activity is fairly scattered in nature. For
now...will allow for vcsh prevailing at all taf sites this
afternoon...with a tempo for MVFR -shra...using timing suggested by the
latest 3km hrrr guidance. Will keep thunder out of the taf for
now...as coverage of thunder is too low to include with confidence
in the taf at this time. Winds look southerly around 10 kts until
this evening...when winds should switch to the west-SW at similar
speeds.

Chance for showers should end by this evening...allowing for ceilings to
gradually scattered out by later this evening. Some MVFR br is possible
for kpsf/kgfl...and perhaps kpou too...late tonight...otherwise
flying conditions should remain VFR with a light west breeze in
place. Cannot totally rule out a brief window for IFR fog at
kpsf/kgfl...but this will probably depend on how much rainfall
occurs this afternoon. Light breeze at kalb should prevent fog/mist
there tonight.

During the day on Thursday...VFR conditions will be in place
through the entire day with west winds around 5-10 kts. Some
diurnal scattered cumulus at 4-5 kft will develop by middle to late morning.

Outlook...

Thursday night: no operational impact. No sig weather.
Friday: no operational impact. No sig weather.
Friday night: no operational impact. No sig weather.
Independence day: moderate operational impact. Scattered rain showers...tsra.
Saturday night: low operational impact. Isolated rain showers...tsra.
Sunday: no operational impact. No sig weather.

&&

Fire weather...
there will one more round of scattered showers and thunderstorms
this evening as a cold front will move through. Then...a drying
trend will finally set in as high pressure will settle in. A
breeze will kick in from the northwest 5-10 miles per hour tonight...10-15
miles per hour with gusts to 25 miles per hour on Thursday. Relative humidity values will drop to the
30s in the valleys...40s higher terrain by afternoon.

A full recovery Thursday night with near 100 percent humidity and
lots of dew. Another dry mainly sunny day Friday with fairly low
afternoon humidity values along with light and variable winds.

A cold front might touch off a lone shower or thunderstorm
Saturday...otherwise it looks dry into early next week.

&&

Hydrology...
the rain this morning did produce some rise on mainly smaller
creeks this morning in our southern hsa. Radar estimated that over
two inches of rain fell near the roundabout basin.

The remainder of the region saw an inch or less of rainfall with
little or no effect on other watersheds.

One more round of showers and scattered thunderstorms this
evening...generally producing average basin rainfall of a quarter
inch or less.

Then...a drying trend will unfold with mainly dry weather expected
for the next five days (outside of a low chance of passing
shower/thunderstorm on saturday).



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
long term...iaa
aviation...frugis
fire weather...hwjiv
hydrology...hwjiv

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