Special Weather Statement, NWS Buffalo, NY

Area Forecast Discussion
National Weather Service Buffalo NY
1006 PM EDT Mon Jul 16 2018

.SYNOPSIS...
A cold front will advance across the area overnight tonight with
showers and thunderstorms ahead of it. Drier air and more
seasonable temperatures will follow this cold front for the
remainder of the week.

&&

.NEAR TERM /THROUGH TUESDAY/...
Showers and thunderstorms continue across the eastern Great Lakes
this evening. Multiple severe thunderstorm warnings and a flash
flood warning have been issued in the forecast area. A strong cold
front is stretched from Central Ontario Province to Eastern
Michigan this evening. A plume of 1.75-2.0 inch PWATs stretches
from the Ohio Valley into Lake Ontario and the North Country.
Heavy rain has been present with showers and thunderstorms
producing rainfall rates of 1- 2 in/hour. Unlike most days,
where the loss of diurnal heating causes updrafts to collapse,
the very warm and humid airmass at the surface will keep
updrafts rooted in the boundary layer. Although 0- 6km shear is
weak across the forecast area, some dry air and 35- 40kts in the
mid-levels per the 00z BUF sounding will keep some storms
tilted and isolated damaging winds gusts are possible ahead of
the cold front tonight.

Showers and thunderstorms are likely across the dry ground in
Western and North-Central NY tonight so many will be happy to
wake up with a wet ground. Localized flash flooding is possible
mainly across the Southern Tier as storms train over the same
area. Radar estimates 2-4 inches across southeastern Allegany
County as of 10:00PM.

The front lags in passing the eastern fringe of the area Tuesday
morning, so showers and low end chances of thunder remain there
after sun up. Otherwise, rapidly drying conditions throughout
the column will yield a drastic improvement in conditions
through the day from west to east. Likewise, cold advection will
knock temperatures back several degrees. This will make heat
index values drop quite a bit more than temperatures, resulting
in fairly comfortable July conditions.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH FRIDAY/...
Tuesday night the mid level trough axis will cross Quebec and
eastern NY, reaching western New England by Wednesday morning. Deep
moisture will have been stripped away by the cold frontal passage,
so the mid level trough axis will cross the area dry. Northerly
upslope flow will bring a modest increase in cloud cover overnight,
mainly across the higher terrain south of the Thruway and east of
Lake Ontario. An incoming cooler and drier airmass will allow lows
to drop back into the mid to upper 50s on the lake plains of Western
NY, and lower 50s for the cooler Southern Tier valleys and east of
Lake Ontario.

High pressure will then build from the central Great Lakes Wednesday
to the eastern Great Lakes Thursday. This will bring another stretch
of dry weather and sunshine both days. Cooler 850mb temps around +9C
on Wednesday will support highs in the mid 70s in most locations,
and around 70 on the hills. Wednesday night will be quite cool with
lows in the mid 50s on the lake plains, and mid to upper 40s in the
cooler Southern Tier valleys and Lewis County. The airmass will
begin to modify on Thursday, with highs back into the lower 80s at
lower elevations and upper 70s for higher terrain.

Thursday night and Friday surface high pressure will drift off the
New England coast, with a mid level cutoff low and associated
surface low moving into the western Great Lakes. Clouds will slowly
increase from west to east later Thursday night and Friday as return
flow begins to advect moisture into the region. The GFS is on the
fast side of the guidance envelope in bringing rain chances into
Western NY by late afternoon. Continued to favor the slower
ECMWF/GEM guidance and kept a dry forecast through Friday evening. A
push of stronger warm advection ahead of the system will bring highs
back into the mid to upper 80s on Friday, with the warmest
temperatures on the lake plains of Western NY with an added boost
from southerly downslope flow.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
Friday night and Saturday a mid level cutoff low and associated
surface low over the western Great Lakes will make only very slow
progress to the east across Michigan. A few widely scattered showers
or thunderstorms may reach Western NY later Friday night and
Saturday, with dry conditions prevailing east of Lake Ontario. A
better chance of rain will arrive Saturday night and Sunday as the
system advances east across Ohio and Lake Erie, with more favorable
forcing and moisture arriving. Model guidance also hints at some
moisture from a sub-tropical system advecting northward along the
eastern seaboard Sunday. Some of this moisture may get pulled back
into the system approaching from the west, although the model
consensus keeps the bulk of this along the east coast. The trough is
forecast to weaken in place by Monday, with a chance of a few more
showers or isolated thunderstorms. Given the convective nature of
all the rain chances this weekend, expect coverage of soaking rain
to be spotty, with only limited improvement of dry soil conditions.

Highs on Saturday will reach the mid 80s at lower elevations, with
upper 70s to lower 80s by Sunday with more cloud cover and shower
coverage. Lows will generally run in the mid to upper 60s on the
lake plains, and lower 60s across the interior along with moderate
humidity. Expect similar near average temperatures to persist
through early next week.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
Showers and thunderstorms expected at the terminals tonight.
Heavy rain will result in IFR conditions at the terminals. Some
storms may be strong with gusts up to 40kts however confidence
is low it would reach the airfields. VFR/MVFR conditions
expected between showers and thunderstorms. A cold front will
move through the terminals from west to east Tuesday.

With the frontal passage, winds will rapid switch from SW to NW
on Tuesday, ushering in clear skies as drier air arrives in the
afternoon. The front will move through KIAG/KBUF early Tuesday
and KART by Tuesday afternoon.

Outlook...

Tuesday night...VFR.
Wednesday through Friday...VFR.
Saturday...VFR, except MVFR in showers and thunderstorms.

&&

.MARINE...
Showers and thunderstorms will move from southwest to northeast
across the lakes tonight as a cold front approaches. SMW's may
be warrented through the overnight.

The cold front will pass across the Eastern Great Lakes region
late tonight and early Tuesday, with west to northwest winds
freshening Tuesday and Tuesday night. This may bring wave
heights and wind speeds to advisory levels, especially on Lake
Ontario on Tuesday.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

SYNOPSIS...Fries
NEAR TERM...Fries/HSK
SHORT TERM...Hitchcock
LONG TERM...Hitchcock
AVIATION...Fries/HSK
MARINE...Fries/HSK

Hazardous Weather Outlook
National Weather Service Buffalo NY
718 PM EDT Mon Jul 16 2018

NYZ001>008-010>014-019>021-085-171800-
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Jefferson-Lewis-
Northern Erie-Genesee-Wyoming-Livingston-Ontario-Chautauqua-
Cattaraugus-Allegany-Southern Erie-
718 PM EDT Mon Jul 16 2018

This Hazardous Weather Outlook is for western and north central New
York.

.DAY ONE...Tonight.

Thunderstorms over the region tonight are forecast to contain
torrential downpours. This could lead to localized flood problems...
particularly for the smaller tributaries and for low lying areas.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

This product, along with other watches, warnings, advisories, and
statements issued by the National Weather Service office in Buffalo
can be found on the internet at http://www.weather.gov/buf

LEZ020-040-041-LOZ042>045-062>065-SLZ022-024-171800-
Upper Niagara River and Buffalo Harbor-
Lake Erie nearshore waters from Ripley to Dunkirk-
Lake Erie nearshore waters from Dunkirk to Buffalo-
Lake Ontario nearshore waters from the Niagara River to Hamlin Beach-
Lake Ontario nearshore waters from Hamlin Beach to Sodus Bay-
Lake Ontario nearshore waters from Sodus Bay to Mexico Bay-
Lake Ontario nearshore waters from Mexico Bay to the Saint Lawrence
River-
Lake Ontario open waters from the Niagara River to Hamlin Beach-
Lake Ontario open waters from Hamlin Beach to Sodus Bay-
Lake Ontario open waters from Sodus Bay to Mexico Bay-
Lake Ontario open waters from Mexico Bay to the Saint Lawrence River-
Saint Lawrence River from Cape Vincent to Ogdensburg-
Saint Lawrence River from Ogdensburg to Saint Regis-
718 PM EDT Mon Jul 16 2018

This Hazardous Weather Outlook is for portions of Lake Erie, Lake
Ontario and Saint Lawrence River.

.DAY ONE...Tonight.

Thunderstorms tonight could produce localized wind gusts over 35
knots.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

This product, along with other watches, warnings, advisories, and
statements issued by the National Weather Service office in Buffalo
can be found on the internet at http://www.weather.gov/buf

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BUFFALO NY
754 PM EDT MON JUL 16 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0520 PM     TSTM WND DMG     1 S NEWARK              43.03N  77.09W
07/16/2018                   WAYNE              NY   LAW ENFORCEMENT

            TREE DOWN ON CLARK RD.

&&

EVENT NUMBER BUF1800516

AR

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BUFFALO NY
923 PM EDT MON JUL 16 2018

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0855 PM     TSTM WND DMG     JAMESTOWN               42.10N  79.24W
07/16/2018                   CHAUTAUQUA         NY   LAW ENFORCEMENT

            TREES DOWN.

&&

EVENT NUMBER BUF1800520

KENYON

Special Weather Statement
National Weather Service Buffalo NY
933 PM EDT MON JUL 16 2018

NYZ012-020-021-085-170230-
Cattaraugus-Allegany-Southern Erie-Wyoming-
933 PM EDT MON JUL 16 2018

...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN WYOMING...CENTRAL
CATTARAUGUS...SOUTHEASTERN ERIE AND NORTHWESTERN ALLEGANY COUNTIES...

At 933 PM EDT, a strong thunderstorm was located 10 miles northwest
of Salamanca, moving northeast at 35 mph.

Winds in excess of 30 mph are possible with this storm.

Locations impacted include...
Salamanca, Springville, Colden, Gowanda, Ashford, Arcade,
Franklinville, Belfast, Cuba and Rushford.

This includes Interstate 86 between exits 27 and 28.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 4209 7858 4238 7902 4277 7857 4231 7806
TIME...MOT...LOC 0133Z 233DEG 28KT 4226 7889

Reynolds

Special Weather Statement
National Weather Service Buffalo NY
1021 PM EDT MON JUL 16 2018

NYZ020-021-170315-
Cattaraugus-Allegany-
1021 PM EDT MON JUL 16 2018

...AN AREA OF STRONG THUNDERSTORMS WILL AFFECT EASTERN CATTARAUGUS
AND ALLEGANY COUNTIES...

At 1019 PM EDT, strong thunderstorms were clustered over eastern
Cattaraugus county and the northern two thirds of Allegany county.
This area of strong storms was moving northeast at 35 mph.

Winds in excess of 30 mph are possible with these storms.

Locations impacted include...
Olean, Alfred, Belfast, Cuba, Rushford, Houghton, Weston Mills,
Caneadea, Hinsdale and Friendship.

This includes Interstate 86 between exits 26 and 32.

Torrential rainfall is also occurring with these storms, and may
cause localized flooding. Rainfall of one to as much as two inches
will be possible by midnight from these storms. Do not drive your
vehicle through flooded roadways.

Frequent cloud to ground lightning is also occurring with these
storms. Lightning can strike 10 miles away from a thunderstorm. Seek
a safe shelter inside a building or vehicle.

Persons in campgrounds should consider seeking sturdy shelter until
this storm passes.

LAT...LON 4200 7844 4249 7844 4247 7775 4220 7776
TIME...MOT...LOC 0219Z 249DEG 31KT 4221 7834

RSH

Special Weather Statement
National Weather Service Buffalo NY
1124 PM EDT MON JUL 16 2018

NYZ021-170400-
Allegany-
1124 PM EDT MON JUL 16 2018

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN ALLEGANY COUNTY...

At 1120 PM EDT, a strong thunderstorm was located near Genesee, or
12 miles south of Wellsville, moving northeast at 40 mph. This
thunderstorm will bring additional rain of a half inch or more to
areas that have already received 2 to 3 inches of rain from earlier
this evening. Water can easily pond in this area and small streams
again briefly rise.

Locations impacted include...
Whitesville and Paynesville.

Heavy rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 4213 7775 4200 7775 4200 7799
TIME...MOT...LOC 0320Z 239DEG 36KT 4194 7792

Thomas

Special Weather Statement
National Weather Service Buffalo NY
1255 AM EDT TUE JUL 17 2018

NYZ007-170615-
Jefferson-
1255 AM EDT TUE JUL 17 2018

...A STRONG THUNDERSTORM WILL AFFECT JEFFERSON COUNTY...

At 1254 AM EDT, a strong thunderstorm was located 12 miles northwest
of Stony Point, or 26 miles west of Watertown, moving northeast at 50
mph.

Winds in excess of 40 mph are possible with this storm.

Locations impacted include...
Watertown, Fort Drum, Stony Point, Clayton, Dexter, Glen Park,
Redwood, Kring Point State Park, Henderson Harbor and Wellesley
Island State Park.

This includes Interstate 81 between exits 44 and 52.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

LAT...LON 4422 7545 4373 7627 4378 7629 4383 7636
      4387 7635 4384 7644 4387 7650 4391 7650
      4396 7644 4396 7634 4402 7636 4405 7642
      4410 7643 4414 7635 4420 7631 4422 7620
      4424 7617 4429 7615 4435 7595 4440 7586
TIME...MOT...LOC 0454Z 241DEG 44KT 4398 7645

Thomas