000
FXUS61 KBGM 241412
AFDBGM

Area Forecast Discussion
National Weather Service Binghamton NY
1012 AM EDT Tue Apr 24 2018

.SYNOPSIS...
A period of transition as dry high pressure this morning, gives
way to an approaching low pressure system with thickening
clouds this afternoon followed by rain late today into tonight.
Showers persist Wednesday and then gradually diminish Thursday.
Another system will yield a good chance of rain by Saturday.

&&

.NEAR TERM /THROUGH TONIGHT/...
10 am update...
Forecast looks good for clouds and showers coming in later
today. Temperatures have shot up into the 50s and low 60s
already but that will slow with the clouds coming in. Dewpoints
higher than yesterday so RH will be higher and above red flag
criteria.

425 AM update...
Dry for now, but rain is en route for tonight.

Surface high pressure is still in control at the moment, yet it
is losing its grip on the region as the center shifts offshore.
Meanwhile, the upper ridge axis just passed overhead but will
also quickly head to the coast this morning and slide further
away. This will open our area to quickly increasing moisture;
first in the upper to mid levels in southerly flow aloft and
then in the lower levels via southeasterly flow. Model trends
favored delaying the onset compared to prior forecast, as it
will take awhile to overcome the significant amount of dry air
in the low levels. Thus, despite increasing and thickening high
clouds, almost all of today will be dry even though radar
returns will appear. Most of it will be virga; drying up before
reaching the ground.

Between 4-9 PM, some sprinkles will start to advect southwest to
northeast across the region. However, the main batch of
measurable rain will be overnight tonight into early Wednesday,
as several shortwaves embedded southerly flow (itself ahead of
evolving upper trough) run up through our region while
southeasterly low level flow also injects marine moisture.
Through tonight, rain amounts are expected to range about 4 to 8
tenths of an inch for Northeast PA-Sullivan County NY, though
the Poconos could get topographic enhancement of upsloping
southeasterly flow, to produce locally near an inch. Further
north, most of Central NY will only get about 2 to 4 tenths of
an inch of rain through tonight.

Temperatures today will be warmest in the northern Finger Lakes
through NY Thruway corridor where mid to upper 60s will be
found, courtesy of partial sunshine early and downsloping winds
through the day. Highs elsewhere will generally be upper 50s-
lower 60s; coolest south due to early thickening of clouds. Lows
tonight will be mainly lower to mid 40s.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
430 AM Update...
Rain will continue Wednesday as northern stream upper trough
digs and meets a weaker southern stream trough. Then Wednesday
night into Thursday, these two features will fuse into a single
compact cutoff low over our region, which will keep daytime
temperatures a bit shy of climatology while also keeping at
least some shower activity around.

Things quiet down late Thursday-early Friday, with highest
Friday climbing back to near normal; upper 50s-lower 60s.
However, a weak wave will move up the Midatlantic Coast.
Uncertain at this time if it will allow showers as far inland as
our region, but some models are trending that direction. I have
for now introduced a slight chance of showers Friday for the
southeastern half of the area. The better rain chances still
wait until the weekend.

&&

.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
4 am Tuesday update...
Our medium-range global models remain fairly consistent with
previous runs. As a result, no changes were made to the existing
forecast for this period.

Indications still are that a mean upper-level trough position
will stay anchored over eastern Canada and the northeastern
CONUS through much of the weekend. As short-waves rotate
through, showery weather and below normal temperatures for the
end of April, are expected.

Early next week, the above mentioned trough should weaken, as
the supporting vortex near Hudson Bay retreats northward. This
should allow significant height rises to take place, signaling
drier and significantly warmer weather.

Previous discussion... 300 pm Monday update...

Start of the period cold rain on back side of surface low and
upper level trough in eastern NY. The rain and low lift
northeast Wednesday night and Thursday. Rain may continue into
Thursday night in the far northeast. Temperatures at low levels
stay above freezing so precipitation should remain as rain.
Cooler highs Thursday in the 50s under the trough and with
neutral advection. Lows Thursday night in the mid and upper 30s.

Weak ridging aloft and weak surface high on Friday before the
next system approaches Friday night. The weekend system a cold
front and narrow but deep upper level trough moving in from the
west. Ahead of this is a coastal that stays well east of the
area. Rainfall amounts look light centered on the daytime
Saturday. Highs in the 50s Saturday. Sunday a large surface
high and upper level ridging moves in with dry mild air. The
high moves to the coast Monday but the region stays dry. Highs
in the 50s Sunday rise to the upper 50s and lower 60s Monday.

&&

.AVIATION /14Z TUESDAY THROUGH SATURDAY/...
12z update... It continues to look dry today, with the onset of
steadier rain/restrictive conditions not taking place until this
evening. As such, it looks like MVFR-fuel alternate
restrictions won`t develop until 00-03z. IFR conditions are
possible towards daybreak, especially at the higher elevation
sites (KBGM and KITH).

S-SE surface winds of 5-10 kt through much of the morning, may
become a bit gusty this afternoon/evening (gusts of 20-25 kt
likely).

Outlook...

Wednesday-Thursday... Restrictions likely with rain showers.
High confidence.

Thursday night and Friday...Generally VFR. Moderate confidence.

Friday night and Saturday...Some restrictions possible in
scattered rain showers. Lower confidence.

&&

.BGM WATCHES/WARNINGS/ADVISORIES...
PA...None.
NY...None.

&&

$$
SYNOPSIS...MDP/TAC
NEAR TERM...MDP/TAC
SHORT TERM...MDP
LONG TERM...MLJ/TAC
AVIATION...DJN/MLJ

NWS BGM Office Area Forecast Discussion

Random Fact

Snow

Snowflakes generally fall from the sky at speeds between one and five miles per hour.