Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Buffalo New York
402 am EDT Wednesday Jun 3 2015
high pressure sliding off the New England coast will bring the
return of light southerly flow across western and north central New
York over the next few days. This pattern will provide for a warming
trend through Friday. Expect dry weather today...with a few showers
or thunderstorms possible by late Thursday and Friday as more
moisture returns to the area. A cold front passage Friday night will
moderate temperatures to near seasonal normals and bring drier air for
Near term /through tonight/...
with weak ridging aloft and a surface high pressure sliding off the
New England coast this afternoon...expect a very quiet weather day
today. Some areas of fog across the southern tier and east of Lake
Ontario...where the winds have been able to go calm overnight...will
burn off quickly after sunrise this morning. Light easterly winds
and 850 mb temperatures to around +10c will make for seasonal high
temperatures/ in the low to middle 70s/ for most locations. The only
exception will be along the South Shore of Lake Ontario where the
lake breeze will keep high temperatures in the 60s. With no real
moisture and mainly downslope flow...expect abundant sunshine across
the forecast area today.
Tonight...despite mostly clear skies...southeasterly winds around 5
knots will favor light downsloping for much of the area...which will
mean warmer overnight lows. This combined with a slightly warmer
airmass will keep overnight lows in the 50s for most areas.
Short term /Thursday through Friday night/...
high pressure will drift east Thursday...with an increasing return
flow bringing warmer more humid air back across our region. Current
model runs trying to show a small area of increased instability
across the southern tier by afternoon. This may result in a few late
day showers or thunderstorms in the vicinity a lake breeze boundary.
Otherwise it should be partly/mostly sunny with high temperatures in
the middle to upper 70s.
Any convection will come to an end by late evening as weak high
pressure returns for Thursday night. However...regardless of dry
conditions...clouds will persist overnight as the next low pressure
system and associated weak cold front approaches from the northwest.
Low temperatures on Thursday night will remain on the milder side
with most lows in the middle 50s to lower 60s as a result of the clouds
inhibiting any nocturnal cooling.
On Friday...the weak cold front will slowly push across our forecast
area. Given the lack of forcing...we are not expecting widespread
convection from the frontal passage.
Both the mainstream GFS and European model (ecmwf) are now in agreement that
sprawling Canadian high pressure centered near James Bay should push
the front south to the Middle Atlantic States during the course of
Friday night. Will taper off the probability of precipitation overnight while leaving just
the chance for a lingering shower late for all areas but the iag
Long term /Saturday through Tuesday/...
a large area of high pressure will drift across eastern Canada
during the first half of the weekend. This should suppress the
moisture from a stalled frontal far enough to our south to
encourage dry pleasant weather across our forecast area...as
temperatures on Saturday will climb into the low to middle 70s.
As this high moves across New England to the Canadian Maritimes on
Sunday...once again...the clockwise circulation around such a
feature will lead to warmer more humid air to return to our region
from the upper Ohio Valley. Temperatures will climb back into the
upper 70s for most areas by Sunday afternoon as a result...although
some late day thunderstorms could develop over the western counties
ahead of an approaching low pressure system.
There will be a higher probability for showers and thunderstorms
Sunday night and Monday though when the area of low pressure will
swing a cold front across the lower Great Lakes.
For Tuesday...weak impulses circulating around a deep upper level
low over eastern Canada could generate more showers across our
Aviation /09z Wednesday through Sunday/...
VFR flight conditions and light easterly winds will be common
through the day Wednesday. The only exception will be early this
morning across portions of the southern tier and east of Lake
Ontario...where areas of shallow fog will develop. Of the taf
sites...kart will be most prone to this fog development...but only
if winds can go calm...as any light easterly winds will should
mitigate fog development. Climatologically...kart is difficult to
fog in...and thus have only hinted at MVFR fog in the taf tempo
Thursday and Friday...VFR/MVFR with a chance of showers.
Saturday and Sunday...VFR.
high pressure will slide off the New England coast today with light
winds and minimal waves on the eastern Great Lakes. Wind and waves
will tick up slightly Friday night as a cold front crosses the lower
Great Lakes...but this looks to be below Small Craft Advisory levels
at this point. Another high pressure will build across the lower
Great Lakes for the weekend...with light winds and minimal waves