Special Weather Statement, NWS Buffalo, NY

Area Forecast Discussion
National Weather Service Buffalo NY
852 PM EDT Thu Mar 15 2018

.SYNOPSIS...
A broad area of low pressure over the Canadian maritimes will
gradually lift north on Friday as an area of high pressure pushes
east across the Great Lakes for the weekend. Northwest flow will
drive some snow showers south of the lakes overnight before tapering
off Friday. The high pressure will support mainly dry weather over
the weekend with temperatures a few degrees below normal.

&&

.NEAR TERM /THROUGH FRIDAY/...
Mid-level trough continues moist cyclonic northwest flow across the
eastern Great Lakes this evening. This flow is driving scattered to
numerous snow showers mainly east of Lake Erie across the Niagara
Frontier south into the western Southern Tier and east of Lake
Ontario. 00z KBUF RAOB shows steep low level lapse rate with and
sufficient moisture from the surface through 700mb. The 850mb temp
was -9C which is not quite supportive for lake effect. Expect the
this pattern to remain in place through the overnight with the mid-
level trough only slowly pivoting east. A surface trough is expected
to drop south across our region overnight helping to support
additional snow showers and bring cooling 850mb temps in its wake.
Model soundings suggest 850mb temps could drop as low as -16C which
would allow some support from the lakes and likely leading to some
lake effect streamers southeast of the lakes overnight. Surface lows
are forecast to drop to the mid teens away from the lakes to low 20s
near the lakes overnight. Additionally a surface pressure gradient
will continue steady 10-15 kt surface winds. Snowfall overnight
should be limited to 1-2 inches southeast of the lakes with 2-4
inches in the higher terrain of the western Southern Tier. The lake
plains and Finger Lakes should see an inch or less of additional
accumulation.

Through Friday, the mid-level trough and associated synoptic
moisture will slowly exit to the east while surface high pressure
begins to build across the Great Lakes. The incoming surface high
will also bring an end to lake contributions as subsidence inversion
builds over western NY. There will be some additional light
accumulations of snow showers generally an inch or less mainly east
of the lakes and across the higher terrain before ending. Some
sunshine will likely develop as low clouds break with departing snow
showers. Cool northwest flow will keep temperatures below normal
with highs only reaching into the mid 20s away from the lakes to low
30s near the lakes. A lingering pressure gradient will allow some
wind gusts to reach into the 20-30mph range.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
Split upper-level flow over the midwest will leave the Eastern Great
Lakes under cool northwest flow as a vertically stacked mid-level
closed low continues to spin over northern Quebec/Newfoundland.
Meanwhile, surface high pressure over Canada will build south and
southeast Saturday. Leftover lake snows south and southeast of the
lakes will quickly shutdown Friday night as drier air and subsidence
from the aforementioned surface high builds into the region.

Saturday, with high pressure building overhead and copious amounts
of mid-March sunshine daytime highs will climb into the upper 20s in
the North Country to the mid-upper 30s across Western New York.
Overnight, lows will drop back into the teens Saturday night with a
few single digit readings found across the north country. Sunday, a
fast moving mid-level shortwave will drop southeast through the
northwesterly flow along with its weak trailing cold front. This
feature will mainly introduce some mid and high cloudiness across
the region Sunday afternoon. Although, a slight chance of a few
flurries or snow shower will be possible across the Finger lakes and
North Country. Otherwise, mainly dry conditions will persist into
Monday with a bit of cooling behind the front.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Surface high pressure centered over Ontario Canada will reassert
itself over our region Sunday night with cooler but dry weather
expected Monday. Meanwhile, a surface low will advance east from the
Midwest and potentially bring a chance of precipitation (more snow)
to our region Tuesday through Thursday. However, don't get to
excited global models (GFS/GEM/EC) have been all over the board with
this next system and uncertainty remains very high with respect to
track and overall intensity. It's quite possible that a large
portion of our forecast area might even remain largely precipitation
free with recent guidance tracking this system well south of our
forecast area. Have kept chance POPs for now with all the
uncertainty at this point through the end of this period.

Temperatures likely will remain below climo as we head towards the
latter half of March. For this time of year highs should be in the
lower 40s and climb towards the upper 40s by the end of the Month.

&&

.AVIATION /01Z FRIDAY THROUGH TUESDAY/...
Mixed IFR and MVFR cigs and vis continue this evening in snow
showers east of the lakes with upper level low circulating cool and
moist air across the eastern Great Lakes. Visibilities will lower to
1-2 miles in heavier showers. VFR will prevail at ROC and ART with a
low chance of some widely scattered snow showers.

High pressure building across the Great Lakes on Friday will bring
improving conditions. All sites will see VFR by Friday afternoon.

Outlook...
Friday night through Monday...VFR.
Tuesday...chance of snow showers with VFR to MVFR.

&&

.MARINE...
Gradient between an area of high pressure over western Ontario
Canada and an area of low pressure over the Canadian maritimes will
keep small craft conditions going into late Friday Night/Saturday
morning. Winds will continue out of the northwest overnight with
respectable mixing potential on Friday. This will keep winds around
20-30 knots, strongest over Lake Ontario, with onshore flow.
Breakers will remain above 4 feet into early Saturday morning.
Satellite continues to show a large ice shelf across the eastern
portions of Lake Erie into the Buffalo area.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 8 PM EDT Friday for LEZ040-041.
         Small Craft Advisory until 2 PM EDT Saturday for
         LOZ043>045.
         Small Craft Advisory until 8 AM EDT Saturday for LOZ042.

&&

SYNOPSIS...Smith
NEAR TERM...Smith
SHORT TERM...AR
LONG TERM...AR
AVIATION...Smith
MARINE...Smith

Hazardous Weather Outlook
National Weather Service Buffalo NY
311 PM EDT Thu Mar 15 2018

NYZ001>008-010>014-019>021-085-161915-
Niagara-Orleans-Monroe-Wayne-Northern Cayuga-Oswego-Jefferson-Lewis-
Northern Erie-Genesee-Wyoming-Livingston-Ontario-Chautauqua-
Cattaraugus-Allegany-Southern Erie-
311 PM EDT Thu Mar 15 2018

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

.DAY ONE...This Afternoon and Tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

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-SLZ022-024-161915-
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-
311 PM EDT Thu Mar 15 2018

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

.DAY ONE...This Afternoon and Tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

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
553 PM EDT THU MAR 15 2018

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

0830 AM     SNOW             S WATERTOWN             43.97N  75.91W
03/15/2018  M13.4 INCH       JEFFERSON          NY   COCORAHS

&&

EVENT NUMBER BUF1800001

JAM

Special Weather Statement
National Weather Service Buffalo NY
955 PM EDT THU MAR 15 2018

NYZ001-010>013-160230-
Livingston-Wyoming-Genesee-Niagara-Northern Erie-
955 PM EDT THU MAR 15 2018

...AN AREA OF HEAVY SNOW WILL AFFECT NORTHERN WYOMING...NORTHERN
ERIE...CENTRAL LIVINGSTON...SOUTH CENTRAL NIAGARA AND GENESEE
COUNTIES...

At 948 PM EDT, an area of moderate to heavy snow was located from
the Greater Buffalo area southeast to central Livingston county.
Locations impacted include... Buffalo, Batavia, Geneseo, Warsaw,
Attica and Depew.

This includes the following highways...
 Interstate 390 between exits 6 and 7.
 Interstate 90 between exits 53 and 48.

Visibilities will drop quickly to less than a half mile in this area
of heavy snow. Roads will be slick and snow covered with a quick one
to two inches of accumulation.

LAT...LON 4263 7797 4277 7846 4278 7846 4290 7891
      4293 7890 4295 7892 4307 7886 4304 7798
      4261 7753
TIME...MOT...LOC 0148Z 240DEG 49KT 4296 7856

Smith