Scientific Forecaster Discussion
fxus61 kbgm 240147
Area forecast discussion
National Weather Service Binghamton New York
947 PM EDT Fri Jun 23 2017
a low pressure system sliding east of our forecast area will
keep our weather unsettled through the weekend.
Near term /through Saturday night/...
947 PM update...
Thankfully, the precipitation across our forecast area through
this evening has been fairly light. With daytime instability
gone, we removed all mention of thunder for the overnight hours.
A stray strike remains possible, but the odds are too low to
include in the grids.
We lowered pops across the board through Saturday morning and
curve-fit the temperatures based on current readings.
Local radars continue to show fairly weak returns and
limited coverage. Coverage is increasing across the southern
tier as a series of mid level short waves move through in
southwest upper level flow. Coverage will continue to increase
late this afternoon and into the evening as the surface cold
front in southern Ontario begins dropping toward the area and
interacts with a very moist airmass. The potential for severe
weather looks really limited as extensive clouds cover has
resulted in cape values of only a 300-500 j/kg. Heavy downpours
are still possible with any significant convection which could
lead to isolated flash flooding. Activity will end from north
to south overnight as the boundary drops south through the
region and pushes the moist airmass out of the area.
Saturday/Saturday night...a dry period as we continue in
upper level southwest flow regime but no significant mid level
waves. A drier northwest surface flow will develop Saturday
morning leading to partly sunny skies with just an isolated
shower possible during the afternoon but almost all areas will
remain dry. Highs will range in the middle 70s to around 80.
Saturday night lows will drop into the middle to upper 50s.
Short term /Sunday through Monday/...
complex upper pattern in the short term and beyond with a broad
trof over the eastern third of the country and a ridge in the
western Atlantic. This will keep the forecast under a somewhat
swift SW flow and changeable weather. Short wave rotating
through the upper low over the Great Lakes will bring a chance
of afternoon showers Sunday. Lingering surface boundary and
upper cool pool will bring a chance again Monday, especially
during afternoon heating.
With the northwest to west surface flow and the lower heights,
temperatures through the period will continue to be below
normal, especially during the day.
Long term /Monday night through Friday/...
upper trof begins to move Tuesday with the axis over the area in
the afternoon triggering showers and thunderstorms once again.
Ridging finally returns on Wednesday and carries into Thursday
as heights build and a 1025mb surface high slides east through
the eastern U.S. Into the Atlantic. Near normal afternoon highs
will return Wednesday but especially Thursday as warm air
advection begins around the back of the high. Thunderstorms
developing along an advancing front should hold off until
Thursday night or Friday, just past the end of the period.
Aviation /02z Saturday through Wednesday/...
a cold front interacting with a very moist atmosphere will bring
sporadic showers to the region this evening. Thunderstorms are
a low probability and not included in forecast at this time.
Due to the very moist nature of the boundary layer, the flight
category will gradually lower into the MVFR/alternate required
category during the late evening hours. A period of
rain/showers seems likely just prior to sunrise as portions of
the tropical remnants of Cindy are forecast to sweep across the
area just ahead of the cold front. After frontal passage widespread
IFR ceilings are expected with a quick improvement to VFR
Saturday morning shortly after sunrise. Breezy with high clouds
are expected for the afternoon.
Southwest winds around 5-10 knots shifting to the northwest
overnight then increasing Saturday morning to around 12 knots.
Sunday - Tuesday...mostly VFR, but shower/storm and brief