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Area Forecast Discussion
National Weather Service Albany NY
412 PM EDT SUN JUL 24 2016

Hot temperatures, increasing humidity and chances for showers and
thunderstorms return for Monday as a frontal boundary approaches
from the west. More dry weather is expected from Tuesday through
the middle of the week as high pressure builds back in across the


Convection in the Great Lakes and OH Valley spilling more high
clouds into western NY/PA and is building east. Upper and low
level ridge axis building east of our region. So, intervals of mid
and high clouds will occur much of the night over our entire
region. Light winds will become light south to southwest toward

There are quite a few different possibilities as to the evolution
and track of convection that develops in the OH Valley later this
afternoon and evening. Various mesoscale models have different
solutions, some showing a weakened small cluster of showers and
isolated thunderstorms along the advancing dew point boundary
around daybreak across the eastern Catskills and mid Hudson
Valley. Other guidance shows the small cluster tracking well south
of the mid Hudson Valley. Other guidance shows most of all the
showers and storms dissipating along the dew point boundary
through the night, but new strong convection rapidly developing
over eastern NY and Western New England around mid morning Monday.

The one constant is the dew point boundary with increasing dew
points building in from the west but the mode and coverage of any
weakening showers and thunderstorms is very much in question.
Boundary layer flow will slowly increase from the west and
southwest, which is downslope, and there is very little upper
dynamics or upper jet support for convection in our region. So,
acknowledging isolated to scattered showers and thunderstorms
toward daybreak into the western Mohawk Valley, eastern Catskills,
mid Hudson Valley and into NW CT. This may be updated once showers
and storms can be tracked through tonight. Low temperatures with
the increasing cloud cover and increasing dew points in the 60s to
near 70...but around 60 northern areas and parts of southern VT.


Guidance again not in full agreement on coverage, timing and
intensity of convection tomorrow. Upper dynamics, upper jet
structure and low level forcing will be relatively weak through
the day but rapidly increasing low level moisture will contribute
to increasing instability. West to southwest boundary layer flow
will be downslope...suggesting scattered coverage, not necessarily
likely. The amount of mixed mid and high clouds will determine
high temperatures but as long as new convection initiates more in
the afternoon, intervals of breaks and thinning of mid and high
clouds should still allow for highs well into the 80s to lower
90s. Heat indices may approach 100 in the mid Hudson Valley and NW
CT but not quite. So, will include in HWO, highlighting the chance
that a Heat Advisory may need to be issued later.

The instability, CAPES may be solidly over 1000 j/kg in many areas
Monday afternoon, along with some hints at some degree of
steepening of midlevel lapse rates, suggests that even with the
scattered nature of the storms tomorrow afternoon, some could
become severe. Our region is in a marginal to slight risk in the
severe weather outlook from SPC, with damaging winds the primary
threat but some hail could occur as well.

The better low level forcing along the advancing low level thermal
and moisture boundary and westerly wind shift looks to be during
the evening and overnight Monday night when some diurnal cooling
should be occurring but keeping potential severe in the forecast
through Monday evening. Some low level drying and partial clearing
could occur before daybreak with lows in the 60s.

Continued drying Tuesday with considerable sunshine and breezy
west to northwest winds. Highs Tuesday in the 80s to near 90.
Similar weather Wednesday but less wind with highs again in the
80s to around 90.


This will be a stagnant period of little atmospheric motion to
get things moving. As such...our region will be more or less stuck
between two frontal boundaries north and south. Waves will ripple
along these boundaries...and showers and thunderstorm will be
possible each day...particularly approaching and during the

After high temperatures from around 80 degrees in the mountains to
the lower 90s down the Hudson Valley on Thursday...showers and an
overall increase in cloud cover will keep daily highs in the around
70 lower or mid 80s range for the balance of the period.
Overnight lows will be in the upper 50s to upper 60s range for the
entire period.  Daytime highs at Albany are in the lower 80s...with
overnight lows in the lower 60s.


A thin sct-bkn ci/cs across the sky this afternoon into the evening
hours will result in VFR conditions.  In fact, expectations are for
the VFR conditions to continue into tonight with an increase and
lowering of the CIGS.  As a warm front moves closer Monday, and
depending on the timing of upstream convection, showers could
approach areas south of I90 Monday morning.  We will place a
PROB30 for KPOU at this time.

A light and variable or northwest flow will continue with a more
northeasterly flow at KGFL due to local effects. Winds will diminish
in the evening with a light southerly flow beginning to develop
early Monday.


Monday Night: Moderate Operational Impact. Scattered SHRA...TSRA.
Tuesday: No Operational Impact. NO SIG WX.
Tuesday Night: No Operational Impact. NO SIG WX.
Wednesday: No Operational Impact. NO SIG WX.
Wednesday Night: No Operational Impact. NO SIG WX.
Thursday: Moderate Operational Impact. Slight Chance of SHRA...TSRA.
Thursday Night: Moderate Operational Impact. Chance of SHRA...TSRA.
Friday: Moderate Operational Impact. Chance of SHRA...TSRA.


Hot temperatures, increasing humidity and chances for showers and
thunderstorms return for Monday as a frontal boundary approaches
from the west. More dry weather is expected from Tuesday through
the middle of the week as high pressure builds back in across the

Relative humidity values will range between 75 and 100 percent
tonight and Monday night. Relative humidity values will drop to
around 50 to 65 Monday afternoon and to around 40 to 55 percent
Tuesday afternoon.

Scattered thunderstorms are expected Monday and Monday night.

Winds will becoming variable around 5 kt or less tonight. Winds
on Monday will become southwest at 15 mph or less. Winds shift to
west and northwest at 15 mph or less Monday night, then increase
to around 15 mph with possible gusts to 25 mph Tuesday.


Dry weather will occur through tonight. However, the next frontal
boundary will approach for Monday bringing additional chances for
showers and thunderstorms. Locally heavy rainfall will be possible
with any persistent storms but basin wide amounts should be a
half inch or less.

Dry conditions return for Tuesday and Wednesday as high pressure
builds back into the region.

Flows continue to be well below normal for mid to late July at
many locations in the Hydro Service Area, especially our western
New England counties.

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.





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