Area forecast discussion
National Weather Service Buffalo New York
632 am EDT Friday may 24 2013
Synopsis...
showers lingering behind a departed cold front will taper off from
west to east today...but unseasonably cool temperatures will be the
rule. High pressure building across the Great Lakes will bring
mainly dry and cool conditions this weekend...before temperatures
will rebound back to above average next week.
&&
Near term /through tonight/...
radar imagery early this morning still shows numerous showers
pushing east across the area...but the back edge of the precipitation is
working into far western New York. As the axis of the upper level trough
pushes across western and central New York today...the showers will
taper off gradually from west to east. Cloudy skies this morning
will also give way to some increase in sunshine during the
afternoon...especially across western New York.
It will be quite chilly today with temperatures expected to range
from the upper 40s to middle 50s. Brisk northwest winds behind the
departed cold front will put even more a chill into the air.
Tonight...the upper trough is forecast to deepen...then close off
over southeast New York and New England. The associated surface low will
remain in place just off the southern New England coast. The moist
cyclonic flow along the western periphery of the low may generate a
few more showers across parts of the north country overnight.
Farther to the west...expect to see a sharp east to west decrease in
clouds. The clearing skies and ongoing cold air advection will allow
temperatures to cool into the upper 30s and lower 40s...with middle 30s
possible across parts of the southern tier. With temperatures
expected to cool into the middle 30s...the possibility of frost exists.
However...still feel that the northwest gradient wind will be strong
enough to preclude the development of frost across most of the
southern tier.
&&
Short term /Saturday through Sunday night/...
our region will be west of an upper level low which is forecast
to stall across New England this weekend. Although the spread in
model guidance has narrowed...there is still some uncertainty as
to how far west showers associated with this upper low will be.
Regardless of model differences...there continues to be high confidence in
fair weather and lots of sunshine for the western half of the
County Warning Area...which includes Buffalo...Rochester...and the southern tier.
There probably will be some clouds and perhaps a shower east of Lake
Ontario through Sunday...before the upper low finally drifts to the
east Sunday night. The forecast represents a consensus of the past
two runs of the GFS/NAM/sref/European/ggem.
Temperatures will continue to be on the cool side...but should
moderate a bit on Sunday. Highs will range from the upper 50s to
lower 60s on Saturday...and should top out in the 60s on Sunday.
Given the northwesterly gradient...expect an Early Lake breeze south
of Lake Ontario. Overnight lows will also be chilly...with some
patchy frost possible in the valleys of the southern tier with lows
in the middle to upper 30s. A modest gradient and warming 850mb
temperatures should limit frost potential elsewhere...with lows
mainly in the lower 40s.
&&
Long term /Monday through Thursday/...
latest medium range guidance suggests mainly dry weather through the
period...along with a gradual warming trend. Most of this period
will feature an upper level ridge over the Mississippi Valley
building eastward. A surface high will set up along the East
Coast...resulting in the development a warmer southerly flow of air.
Have a high confidence in dry weather for Monday and Monday
night...with the surface high likely to be across our region. After
this...a weak warm frontal boundary will extend from the upper
lakes...southeastward to the middle Atlantic coast. This boundary is
forecast to gradually lift toward our region through mid-week. Expect
scattered thunderstorms along this boundary...but have a low
confidence in timing when it will cross our region. The 00z GFS/ggem
lift the front across our region Wednesday...with the European
nearly a day slower. For now...with go with a persistent slight
chance for thunderstorms during the period. The passage of the front
will also key even warmer temperatures. Highs will likely rise into
the lower 80s by mid-week...with temperatures possibly even warmer
if the earlier frontal passage verifies.
&&
Aviation /12z Friday through Tuesday/...
widespread MVFR to IFR conditions prevail across the area early this
morning as plenty of moisture lingers behind the departed cold
front. The showers will slowly end from west to east during the day
as the upper level trough moves slowly east. IFR ceilings will improve
to MVFR as the rain tapers off. Later this morning and during the
afternoon...ceilings should lift to VFR...then scatter out...especially
across western New York. Clouds will continue to thin out tonight as
drier air works in from the west. The exception to this general
trend will be east of Lake Ontario where clouds and possible showers
will linger in the wake of the low that will be stationed off the
New England coast.
Outlook...
Saturday through Tuesday...VFR.
&&
Marine...
the modest northwest flow behind the departed cold front will
maintain small advisory conditions on the lake this morning into the
early afternoon. Low pressure that will be lifting up the New
England coast will maintain a northwest flow through the
weekend...but wind and waves are expected to remain just below
levels needed for a Small Craft Advisory.
&&
Buf watches/warnings/advisories...
New York...none.
Marine...Small Craft Advisory until noon EDT today for lez040-041.
Small Craft Advisory until 2 PM EDT this afternoon
for loz043-044.
Small Craft Advisory until noon EDT today for loz042-045.
&&
$$
Synopsis...tjp
near term...tjp
short term...apffel
long term...apffel
aviation...tjp
marine...tjp
