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Area forecast discussion 
National Weather Service Albany New York
206 am EDT Monday may 25 2015

Synopsis...
the weather will turn warm and humid this week along with chances
for showers and thunderstorms especially during the middle of the
week.

&&

Near term /until 6 am this morning/...
regional radars shows precipitation associated with approaching
warm front over western New York. The airmass currently across the
local area is very dry...the precitable water value on the 00z
aly sounding was only 0.51 inches. Guidance indicated the rainfall
associated with the warm frontal should be limited to northern
New York so pulled back on probability of precipitation and now only have chance probability of precipitation for
showers moving into the northwest corner of the forecast area
through sunrise.

Much milder overnight than previous nights with lows expected to
be mainly in the 50s.

&&

Short term /6 am this morning through Tuesday night/...
Memorial Day...broad ridge off the southeast coast along with
slowly migrating upstream trough will result in a much warmer and
humid air mass to advect into the region as precipitable waters climb in excess
of 1.50 inches. As the warm front lifts northward through the
region...some elevated showers and some rumbles of thunder are
possible mainly north of i90. Otherwise...considerable cloud
coverage is expected. H850 temperatures moderate into the middle-teens range
along with a west-southwest flow too assist with valley
temperatures to warm into the lower 80s with mid to upper 70s elsewhere.

Monday night...the main thrust of moisture transport will be well
north of the region with a trailing middle level front settling south
of i90 overnight. NCEP model suite suggests a couple of waves will
transverse the southern portions to warrant a continued chance
for showers/storms. It should remain rather mild and humid with
mainly 60s expected across the region.

Tuesday-Tuesday night...another pv anomaly is forecast from the global
models to come out of The Four Corners region and track into the
central Great Lakes region. Downstream response will be the middle
level front to lift northward through the period. So the chance
for additional showers/storms to impact the region. Cloud coverage
will have an impact to overall instability as current sbcapes are
expected to climb to 500-1000 j/kg with precipitable waters of 1.25-1.75 inches.
The middle level lapse rates are not steep. 0-6 km bulk shear remain in
the 20-30 knots range. So some organization of the convection is
possible which could also be accompanied by moderate to heavy
rainfall. Highs mainly in the middle 80s in the valley areas...with
u70s to l80s over the hills and mountains the convection should
diminish in the evening with a sticky/muggy night setting up with
lows in 60s. Humidity levels will be higher as dewpoints climb
through the 60s.

&&

Long term /Wednesday through Sunday/...
the season/S first real Bermuda high will continue to be established
over the eastern Seaboard during much of the extended period. The
net result will be above normal temperatures along with moderate to
high levels of humidity and threat of showers and thunderstorms.

On Wednesday...a middle level trough between James Bay and the northern
Great Lakes...and its associated surface cold front will attempt to
move southward into New York state. Disturbances along this boundary will
increase thunderstorm chances across our region by late Wednesday
into Wednesday night.

At this point...most long term guidance indicated this middle level
disturbance slides on by late Thursday...replaced by brief ridging
on Friday morning. However...another disturbance riding through the
Great Lakes will increase the chances of showers and thunderstorms
by Friday afternoon and night. These chances continue into Saturday.
By Sunday...high pressure building over James Bay might push the
front south of our region...which would allow slightly cooler drier
to filter in. This far out...that is not a certainty...so we will
continue with low to slight chances on Sunday.

The potential is there for any of the thunderstorms to contain heavy
rainfall...and especially on Wednesday...with projected convective available potential energy to
over 2500 j/kg...some of the storms could become quite strong on
that day. Also precipitable water values look to reach over 1.5 inches...well
above normal for the time of year.

Hopefully this shower activity can bring some relief to our
increasingly dry conditions.

Daytime highs will generally top out in the 80s Wednesday through
Saturday...with some of the hotter spots having a shot at 90
especially from the capital region south...if we get enough of
sunshine each of these days.

By Sunday..high temperatures look to cool to 65-70 across the
Adirondacks and greens...70s elsewhere.

Overnight lows will average in the 60s...cooling a little by Sunday
morning.

&&

Aviation /06z Monday through Friday/...
a warm front will move north of most of the forecast area
today...and become stationary near the St Lawrence River valley.
Weak disturbances will move along the boundary tonight into tomorrow.

VFR conditions are expected to continue through at least 06z/Tuesday at
kgfl/kalb/kpou/kpsf. Clouds will thicken and lower this morning
into the afternoon. Mainly middle and high clouds will impact the
terminals prior to 16z. Some showers may reach kgfl between 16z-19z
and a vcsh group was placed there. A better chance of showers is
possible towards 22z...and they were placed in the taf with VFR
conditions.

A vcsh group was placed in kalb/kpsf in the late afternoon with some
the warm advection showers S/southeast of the boundary. Kpou will see some
cumulus...but no vcsh groups were added yet.

The winds will be light to calm this morning...except at kalb where
a S/southeast breeze of 4-8 kts will continue. The winds will increase
from the S to southeast at 5-10 kts by late morning...then 10-15 kts by the
late PM with some gusts to 20-25 kts at kalb/kpsf...as the the warm
front will be well north of the region.

Outlook...

Tuesday-Fri: moderate operational impact. Chance of mainly PM
rain showers...tsra.

&&

Fire weather...
the relative humidity values will increase to 75 to 90 percent by Monday
morning. The relative humidity values will be higher Memorial Day afternoon in
the 35 to 55 percent range.

The winds will become light west-southwest winds to calm
tonight...and then increase from the south to southwest at 5 to 15
miles per hour on Memorial Day.

A warm and increasingly humid week on tap with opportunities for
showers and thunderstorms mainly each afternoon and evening hours.

&&

Hydrology...
no widespread Hydro problems expected over the next 5 days...with
river levels holding or falling through the period.

The U.S. Drought monitor has now included much of eastern New York and
western New England in the d1 category...which is considered
moderate drought.

The threat for scattered showers and thunderstorms will increase through
the middle week period within the more humid air mass. Some locally
heavy downpours will be possible Tuesday through the middle week with
any thunderstorms.

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

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