512 
fxus61 kbgm 120533 
afdbgm 


Area forecast discussion 
National Weather Service Binghamton New York 
1233 am EST Friday Mar 12 2010 


Synopsis... 
a complex area of low pressure over the middle Atlantic region will 
remain nearly stationary...and will bring periods of rain to the 
area through the weekend. The rain may be heavy at times on 
Saturday and Sunday...especially over the Catskills and Poconos. 


&& 


Near term /through today/... 
updated at 720 PM... 
lower cloud deck is spreading northward across the 
Poconos/Catskills early this evening...as a moist southeasterly 
flow is gradually increasing in the boundary layer. We expect this 
trend to continue...with much of the forecast area becoming 
overcast by later tonight. 


Forcing...however...remains quite weak...with most of the upper- 
level support well to our south and west. Moist upslope flow into 
the higher terrain of northeast PA and the Catskills...may bring 
some light showers or patchy drizzle after 06z...but we think that 
will be about it for precipitation overnight. 


Temperatures remain fairly mild this evening (upper 40s and 
50s). Given neutral to slight warm advection aloft...and little 
potential for radiational cooling overnight...we decided to raise 
our minimum temperatures by a few degrees most places. 


The prospects for rain should increase by later Friday 
afternoon...with better jet dynamics/forced ascent coming into 
play...and acting on a deepening moisture supply. Even 
then...though...most of the initial rainfall should stay 
concentrated across the southern half of the forecast area. 


&& 


Short term /tonight through Sunday/... 
complex area of low pressure will bring periods of rain to the area into 
this weekend. Some hints of a wintery mix across the higher 
elevations during the overnight hours from the NAM/GFS profiles...but 
this is not reflected in the srefs and this cooling may be 
overdone. If it did occur effects would appear to be minimal and 
confined to hiest elevations. So we've focused in the +ra potnl 
for this event and there is good agreement that the Poconos and 
Catskills stand the best chance to see sig event-total rain amts (2-3 
inches) this weekend with lesser amts to the north and west. In 
fact...models suggests some shadowing across central New York in this southeast 
flow...reducing precipitation amts across those areas. After collab with our 
neighbors...we've decided to hold off on any Flood Watch issuance 
at this time...but watches will likely be issued with later forecasts 
due to combination of rainfall and snowmelt if models retain 
continuity. It may become rather blustery across the higher elevations 
especially Catskills and Poconos where enhanced low level jet will likely 
be located. 


&& 


Long term /Sunday night through Thursday/... 
Saturday night and Sunday periods begin with a trough exiting the 
eastern forecast area, and showers coming to an end. High pressure 
will begin to rebuild from the Ohio Valley on Monday, with a cool 
northwesterly flow. 


Heights rebound significantly on Tuesday as ul ridge axis pushes 
eastward. Entire northeastern U.S. Will be solidly under surface 
high pressure. Height fields on Tuesday-Thursday are similar to 
those witnessed over the past several days in the northeast. With 
that in mind, the upper 40s forecast by the longer range MOS 
guidance seems too cool. We have hedged our forecast into the 
lower 50s, but upside remains. 


After Sunday, conditions will be fair with mostly clear skies 
through the period. 


&& 


Aviation /06z Friday through Tuesday/... 
MVFR at all sites to begin taf period with low level moisture 
streaming in on southeast flow. May see an occasional IFR ceiling at 
bgm/avp through daybreak. After sunrise...ceilings improve a 
tad...with Elm/rme potentially rising to IFR while remaining sites 
range from 1500-2500ft. Rain will begin to affect avp by middle- 
morning...then try to spread north during the afternoon. Expect 
Elm/bgm to see rain try to develop after 20z and become more 
steady after 00z. This area will gradually work north into 
ith/syr/rme late this evening. 


Southeast winds through the period. Winds will start off from 
5-10kts through morning...then increase by late morning. Gusts to 
near 20kts expected during the afternoon. Low level inversion may 
prevent much more in the way of mixing after this time...though 
higher elevation sites may see gusts to 25kts toward end of taf 
period. 


Outlook... 


Late Friday night into Sunday night...IFR/MVFR in rain/fog...especially 
through Sunday morning. 


Monday...imprvg to VFR. 


Monday ngt/Tue...VFR 


&& 


Bgm watches/warnings/advisories... 
PA...none. 
New York...none. 


&& 


$$ 
Synopsis... 
near term...mlj 
short term... 
long term...djp 
aviation...pvn