Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Buffalo New York
931 am EST Sat Feb 28 2015
high pressure passing over Pennsylvania will produce bright sunshine
across the majority of the region today...with only some nuisance
light lake effect flurries found east of Lake Ontario. As the high
exits the East Coast late tonight and Sunday...a wavy frontal
boundary will approach the region. This next system will generate
widespread accumulating snow during the second half of the weekend.
A warmer...second storm system will impact our region by middle week
with a mixed bag of precipitation and possibly some strong winds.
Near term /through tonight/...
high pressure centered over Pennsylvania will supply plenty of
bright sunshine across the western counties today...but it will
remain cold. 850 mb temperatures in the minus teens celsius will only support
afternoon highs in the upper teens to lower 20s f...and while these
readings will be higher than the past few days...it will still be
some 15 to 20 degree f below normal.
While western New York will bask under sunny skies this last day of
February...a cold westerly flow will keep light lake effect flurries
in place east of Lake Ontario. This nuisance activity will be
severely limited by several factors...including a low cap of under
5k feet and significant ice cover at the east end of the lake. Also
working against significant snow accums will be an increasingly
sheared boundary layer. As a result...expect nothing more than
flurries across northern Oswego County and the Tug Hill shifting
north into Jefferson County this afternoon and dissipating with
little or no accumulation.
Tonight...the aforementioned surface high will make its way to the east
East Coast. This will encourage the low level winds to back to the
south...thus pushing any light lake induced flurries northward
across the northern portion of Jefferson County where they will end
completely by late evening. Elsewhere...clear skies over the western
counties during the evening will give way to increasing clouds late
as a wavy frontal boundary will approach from the west. The
thickening clouds over the far western counties could even support
some light snow by daybreak Sunday.
Warm advection ahead of the ill defined baroclinic zone will lead to
slowly rising temperatures after midnight. After reaching overnight
lows within a few degrees of zero during the first half of night...
most areas should experience a 5 to 10 degree rise in the Mercury by
Short term /Sunday through Monday night/...
high pressure will move off the middle Atlantic coast early Sunday and
a return flow of moisture and warmer overrunning air will set the
stage for the next accumulating snow event.
The upper flow will be quasizonal with a series of diffuse vorticity
maxima...but the driving forces for the snowfall may be found in the
boundary layer and even further aloft at jet stream level of 300mb.
Forcing will only initially be isentropic with a broad region of
warm advection earlier Sunday...then further supported by a deeper
layer of lift associated with the left exit of a 160kt 300mb jet
streak over northern IL/in/OH...providing enough lift to support a
widespread light to moderate snow fall Sunday afternoon and evening.
Warmer profiles ahead of the surface low should hold snow ratios
down to an average of 12:1 during much of the event until colder air
circulates in behind the surface wave later Sunday night into Monday
with overall quantitative precipitation forecast from this system from a third to a half inch. While
all counties should see a few inches of snow...the southern tier has
the highest probability of 6 of more inches Sunday and Sunday night
due to closer proximity to the forcing contributed by the low level
jet and deeper moisture field. Have issued a Winter Storm Watch
covering this area.
Temperatures Sunday will climb toward 30 then only slip into the
upper teens to lower 20s Sunday night with falling snow and cloud
cover. Wrap around moisture and deformation on the back side of the
departing low on Monday will continue chances of some limited snow
tapering off through the day. Temperatures Monday will warm toward
the upper 20s early then fall through the afternoon with the cold
advection behind the storm. Pacific based high pressure will build
over the forecast area behind the departing storm with clearing
skies going into Monday night. The cold advection...clear skies and
light winds will promote a return to below normal low temperatures
dropping to around 10.
Long term /Tuesday through Friday/...
just as we are finished clearing the driveways and sidewalks from
sundays storm...another stronger and warmer storm will quickly
approach for Tuesday and Wednesday with a potential for an icy mix
followed by strong winds. Several strong shortwave disturbances with
attendant vorticity maximum will eject eastward out of a full
latitude western states trough Tuesday triggering a rapidly
deepening Great Lakes cutter type low. Deep southerly flow ahead of
this system will spread a plume of warm moist Gulf sourced air
northward across the Ohio Valley and northeast Tuesday night.
While snow looks to begin arriving across the forecast area Tuesday
with sub-freezing temperatures in place...warm air aloft under
southerly flow will override colder sub-freezing surface
temperatures later Tuesday into Tuesday night producing a warm nose
in vertical temperature profiles. This will likely cause snow to
change to an icy mix overnight with some sections possibly even
going over to plain rain as temperatures push toward 40 degrees.
The mature low will shift just northwest of western New York on
Tuesday night into Wednesday with the systems cold front and
possible trailing strong winds crossing the forecast area through
Wednesday. After a short period of plain rain ahead of the front the
rain will mix with snow as the front shifts east. The track of this
deepening low cutting just to the northwest is a favorable pattern
for strong winds across our forecast area. Models show a significant
pressure fall-rise couplet crossing directly across western and
north-central New York indicating the start of the downward Transfer
of a 40-50kt low level jet just above the surface. This system will
need to continue to be closely watched in the coming days with the
wintry mix and potential for strong winds. Cold air will continue to
filter across the region Thursday and Friday with a western Canadian
sourced high working across the central states. Expecting mainly dry
dry weather toward the end of the week with a return to sub-freezing
Aviation /15z Saturday through Wednesday/...
high pressure over Pennsylvania will supply near cloud free VFR
conditions across the western counties today...while a cold westerly
flow over Lake Ontario will continue to generate some local MVFR
conditions in lake effect flurries and light snow showers for sites
such as kart and kgtb.
While the nuisance lake flurries will push north and diminish to
flurries tonight...clear skies over the western counties will give
way to increasing clouds overnight. The lowering and thickening
clouds could even support some light snow over the far western
counties by daybreak...resulting in deteriorating VFR to at least
Sunday and Sunday night...IFR in widespread snow.
Monday...MVFR with snow showers...then improving to VFR.
Tuesday...becoming windy. MVFR/IFR with a wintry mix.
Wednesday...windy. MVFR with snow showers.
high pressure centered over Pennsylvania today will push east to the
coast tonight. The relatively weak surface pressure gradient will thus
keep winds and waves (in ice free areas) below Small Craft Advisory
Sunday and Sunday night...a wavy frontal boundary will gradually
push across the lower Great Lakes. While generating widespread light
to moderate snow...this scenario will continue to promote light
winds through at least the first half of Sunday night. Winds will
then freshen ahead of a strong area of high pressure that will push
southeast from the northern plains. Small Craft Advisory conditions
will be likely on Lake Ontario by midday Monday.
there is the potential for ice jam flooding Tuesday night and
Wednesday across the Niagara Frontier and western southern tier
The cold weather has caused creek and river ice to increase
significantly during the past few weeks. Outside of fast flowing
areas...virtually all the creeks and rivers are frozen with a very
thick ice pack in place. Ice exceeds a foot in many slow flowing
Low pressure is forecast to track west and north of western New
York Tuesday and Wednesday. This path will push warmer air into
the area...possibly changing precipitation to rain. At this
time...around an inch of rain is possible Tuesday night into early
Wednesday across western New York. That amount of rain may cause
creek and river ice to break up and possible ice jam flooding.
---this February is wrapping up to be one of the coldest and
snowiest months in our primary climate stations history. The
continued northwest flow of bitterly cold air has left the month
of February a historic month that will be a benchmark mark for
years to come. Below are the coldest months in each stations
history. Temperature records for Buffalo and Rochester go back to
1871...while temperature records in Watertown go back to 1950.
Station: value (f) month (year)
Buffalo 11.6 Feb (1934)
13.4 Feb (1875)
13.8 Jan (1977)
14.1 Jan (1918)
14.6 Feb (1885)
14.9 Feb (1979)
15.5 Feb (1978)
15.6 Jan (1920)
15.6 Jan (1912)
16.2 Jan (1945)
Rochester 12.6 Feb (1934)
13.7 Feb (1979)
14.4 Feb (1875)
14.5 Feb (1885)
14.8 Jan (1918)
14.9 Jan (1994)
15.2 Jan (1945)
15.5 Jan (1977)
15.7 Jan (1981)
16.1 Jan (1920)
Watertown 6.4 Dec (1989)
6.5 Jan (1970)
6.9 Jan (1994)
7.9 Feb (1978)
8.0 Jan (1981)
8.1 Jan (2004)
8.4 Feb (1979)
10.0 Jan (2003)
10.1 Jan (1977)
10.3 Jan (1961)
Current monthly average temperatures are listed on the cf6 climate
---February has also been a snowy month as a persistent track of
clippers within a northwest flow has maintained nickel and dime
snows through the month...this after a significant synoptic storm to
start February. Below are the top snowiest february's on record.
Snowfall records go back to 1884.
Station: snow (in) year
Buffalo 1 54.2 1958
2 49.5 1960
3 46.2 2015 (data through 2/27)
Rochester 1 64.8 1958
2 58.3 1960
3 46.5 2007
4 45.2 2015 (data through 2/27)
--- Buffalo New York has remained at or below freezing since
January 30th. Below is a list of longest consecutive days at or
below freezing in buffalo's history.
Station: run length end date
Buffalo45 daysfeb 8 1977
41 daysmar 8 1978
34 days Feb 10 1985
31 daysfeb 24 1901
29 days Feb 27 2015
28 days Jan 12 1881
--- it is likely that Buffalo remains below freezing the entire
month of February. This has happened once before...in the year 1978.
---Rochester has had 9 days this month with minimum temperatures
falling below zero. Below is a list of greatest number of days
in February with minimum temperatures below zero...
9 2015 (data through 2/27)
The greatest number of days in a month that have minimum temperatures
fall below zero is February 1979...and also January 1994.
The greatest number of days in a winter season in Rochester that
have minimum temperatures fall below zero is 15 days set back in
---Watertown has had 19 days this month with minimum temperatures
falling below zero. Below is a list of greatest number of days in
February with minimum temperatures below zero...
19 2015 (data through 2/27)
New York...Winter Storm Watch from late tonight through Monday morning