Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Buffalo New York
1106 PM EST Tuesday Mar 3 2015
colder air in the wake of a complex storm system will overspread the
region Wednesday and Wednesday night...while strong high pressure
will settle south across the center of the country. This will
eventually lead to some all too familiar frigid weather for
Wednesday night and Thursday when temperatures will average 15 to 20
degrees below normal.
Near term /through Wednesday/...
a complex storm system produced a wide variety of accumulating
wintry precipitation across our region during the past 18
hours...but the steadiest precipitation has now pushed off to our
east. While some spotty light rain will be found across the western
counties overnight...new ice related problems are no longer
expected. There could still be some leftover pockets of light
freezing rain east of The Finger lakes though...so will leave the
Winter Weather Advisory in place in that area until 4 am.
In terms of temperatures...the Mercury will continue to climb in
most area overnight to as high as 40 over the western counties and
the low to middle 30s east of Lake Ontario. A cold front pushing
through the area by daybreak will then start a trend of lowering
On Wednesday...the very brief bout of milder weather will give way
to strong cold advection. Arctic high pressure over the Canadian
prairies will settle to the southeast across the northern plains and
upper Mississippi Valley...while the aforementioned storm system
will make its way across northern Quebec. After morning high
temperatures near or above freezing...temperatures will gradually
sink back into the 20s during the course of the afternoon.
The slow return to colder weather on Wednesday will be accompanied
by mainly precipitation free conditions...except leftover morning snow
showers over the southern tier...and some weak lake effect snow
showers east of Lake Ontario.
Short term /Wednesday night through Thursday night/...
synoptically during this period another cold high will gradually
spread into the area with much below normal temperatures expected.
Lake effect snow can be expected in the west northwesterly flow
downstream of the ice free area on Lake Ontario.
Light lake effect snow showers can be expected within a fairly
unidirectional west northwest flow regime Wednesday night and
Thursday. Forecast sounding inversion heights are expected to
increase to the 4-6kft range which may support Minor Lake effect
snow for areas east and southeast of Lake Ontario downwind of the
Thursday will likely be frigid as 850 mb temperatures hover around
-20c. Some warming can be expected Friday with the approach of
another shortwave and isentropic lift.
Long term /Friday through Tuesday/...
the models are looking more consistent for the middle week system with
a lot of ridging aloft and a wave running up the front to our west.
This would allow for warmer air to flood across the Ohio Valley and
eastern Great Lakes. Still not very comfortable with the exact track
and strength of the surface low and the specific timing. The warm up
will be slowed to some extent by the extensive snow cover but there
certainly seems to be an increasing chance that we will be on the
warm side of the system.
Will continue the trend of nudging up forecast temperatures and
allowing for a change to rain. Will not go as warm as it could get
just yet given that we are still 5/6 days away and no confidence yet
on the exact timing. The warmest temperatures may well occur Tuesday
night or early Wednesday...offset of the normal high/low forecast
times. Temperatures could be already be on the way down by daybreak
Wednesday...or it could be 50 degrees. Other possibilities will have
to examined as confidence increases and we get more comfortable with
the timing such as the risk of flooding and the threat of
Aviation /04z Wednesday through Sunday/...
a wealth of low level moisture and the passage of a cold frontal
boundary will keep MVFR ceilings in place across the majority of the
region overnight. Across the southern tier...IFR ceilings will gradually
lift to MVFR by daybreak.
On Wednesday...conditions will improve to VFR as high pressure over
the northern plains will gradually push across the middle western
Thursday...mainly VFR but with a chance of snow Showers. Lake effect
snow likely southeast of Lake Ontario.
Friday into Sunday...mainly VFR.
a relatively tight surface pressure gradient in the wake of a storm
system to our north will produce gusty winds across Lake Ontario
through the day Wednesday. This will justify keeping a Small Craft
Advisory in place for the New York nearshores of Lake Ontario.
As high pressure builds across the middle west and Ohio Valley late
Wednesday and Thursday...winds will drop below Small Craft Advisory
New York...Winter Weather Advisory until 4 am EST Wednesday for
Marine...Small Craft Advisory until 8 am EST Wednesday for loz043-044.
Small Craft Advisory until 7 PM EST Wednesday for loz042.