Area forecast discussion
National Weather Service Buffalo New York
257 am EDT sun may 26 2013
Synopsis...
Canadian high pressure building across the Great Lakes will bring
mainly dry and cool conditions for the remainder of Memorial Day
weekend. Some of the typically cooler areas will see frost again
Monday morning. Then temperatures will warm to above average by
middle-week with the next chance of thunderstorms on Wednesday.
&&
Near term /through tonight/...
a vertically stacked area of low pressure in the Gulf of Maine will
slowly lift to the north today. Moisture on the western periphery of
this low will continue to clip the Eastern Lake Ontario region
through this morning...but should taper off this afternoon as the
low slowly pulls away. Otherwise...the western two-thirds of the County Warning Area
will be sunny today.
As was the case yesterday...temperatures will start off near
freezing in the cooler valleys of the southern tier and in parts of
Wyoming and Erie counties. Elsewhere will be chilly too...but a
modest wind should prevent much in the way of frost this morning.
Temperatures will warm quickly today with highs mainly in the lower
60s.
Tonight...high pressure will build into the region from the upper
lakes. While temperatures aloft will be warmer...light winds will
allow for nearly ideal radiational cooling tonight. Because of
this...some additional locations will have frost tonight. There is a
good possibility of freezing temperatures again tonight in western
portions of the southern tier and in the Boston Hills. While the
immediate lakeshores should be safe...isolated frost is possible
across interior portions and even the Eastern Lake Ontario region. To
avoid confusion...will allow the current frost/freeze headlines to
expire before issuing additional headlines for tonight.
&&
Short term /Monday through Tuesday night/...
Sunday night will again be chilly as surface high pressure settles
southeastward towards western New York. Subsidence with this feature
will promote clear skies and with a relaxed pressure gradient this
will allow for winds to go calm...especially across wny. A slight
pressure gradient across the north country with the lingering
surface low over Atlantic Canada may keep a slight wind through the
night. With the ideal radiational cooling conditions lows will fall
down into the 30s...with freezing temperatures likely across the
southern tier...southern Erie and Wyoming County. Will issue a
freeze watch for the southern tier...southern Erie and Wyoming
counties starting at 11 PM Sunday night as clear skies and light
winds will allow for temperatures to quickly radiate.
With the high pressure camped over the region Monday...Memorial Day
will be sunny with temperatures still a bit on the cool side...with
highs in the upper 60s for most.
Monday night a few clouds will start to build from the west as a
elongated surface warm front pushes northeastward. There is still
some uncertainty within the operational models with the 12z NAM and
rgem a bit faster with moisture advection and the warm front than
the 12z GFS and European model (ecmwf). Will bring a few showers into the southern
tier late Tuesday...and as the warm front nears the region Tuesday
night bring a chance for showers through the night across the
region. Instability is limited ahead of this warm front and will
just have showers in the forecast through the night with the weak
isentropic lift. The southerly winds and clouds overnight night will
keep lows more on the mild side...with temperatures dropping off
into the upper 50s and lowers 60s.
&&
Long term /Wednesday through Saturday/...
we will finish the last few days of may and start June with a Summer
like feel. An upper level ridge will build early in the period over
the eastern states along with increasing surface temperatures and
humidity. The ridge will weaken some Friday and Saturday which will
slow the warming trend.
For Wednesday a weak warm front will lift across the County Warning Area. A weak
upper level shortwave cresting over the ridge combined with building
moisture will bring a chance for showers and thunderstorms through
the day. As this warm front lifts northward the focus for showers
and thunderstorms Wednesday night will be across the north country
with a warm and muggy airmass lingering farther to the south.
On Thursday the upper level ridge builds across the Great Lakes
region and this should limit the showers and thunderstorms across
the region.
A shortwave trough diving southeastward from James Bay and across
Quebec will weaken the ridge Thursday night and into the weekend.
With the falling heights aloft expect temperatures to peak in the
Thursday-Friday timeframe and then a little cooler to start next
weekend...though still above normal.
A back door cold front will drop southward from Canada and bring the
chance for showers and thunderstorms Thursday night to the north
country...and with the weak boundary remaining over the County Warning Area on
Friday...possibly another pop up storm Friday afternoon. For now
will keep Friday dry and see where this boundary lingers. South of
this boundary temperatures will climb into the low to middle 80s.
On Saturday an upper level trough will drop into the western Great
Lakes region. Showers and thunderstorms will accompany this feature
with activity likely to remain just to our west through the daytime.
Highs on Saturday will be a degree or two cooler than Friday.
&&
Aviation /07z Sunday through Thursday/...
VFR conditions will be in place across all of western and north
central New York through tonight. Despite some leftover light rain
east of Lake Ontario tonight and early today...high pressure building
east across the Great Lakes region will keep VFR conditions in place.
Outlook...
Monday and Tuesday...VFR.
Wednesday...mainly VFR with a chance of showers and thunderstorms
and associated brief MVFR/IFR.
Thursday...mainly VFR.
&&
Marine...
low pressure in the Gulf of Maine and high pressure over the
western lakes will result in a persistent moderate northwest flow across
the lower lakes for today. Expect small craft conditions to continue
on Lake Ontario into this afternoon when the pressure gradient
finally begins to relax as the high builds eastward toward the
waters. Winds should be on the light side early next week...then an
approaching frontal boundary will potentially result in Small Craft
Advisory winds mid-week.
&&
Buf watches/warnings/advisories...
New York...freeze watch from this evening through Monday morning for
nyz012-019>021-085.
Freeze warning until 8 am EDT this morning for nyz019>021.
Marine...Small Craft Advisory until 2 PM EDT this afternoon for
loz042>045.
&&
$$
Synopsis...apffel
near term...apffel
short term...Thomas
long term...Thomas
aviation...apffel
marine...apffel/tjp
