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fxus61 kbgm 172316 
afdbgm 


Area forecast discussion 
National Weather Service Binghamton New York 
716 PM EDT Wednesday Mar 17 2010 


Synopsis... 
a building ridge of high pressure will continue to provide for 
fair and pleasant conditions across the area. Unreasonably warm 
temperatures will persist with afternoon high temperatures 
expected to climb into the upper 50s to lower 60s both Thursday 
and Friday. Even warmer conditions are then likely on Saturday 
before a strong cold front plows through the area on Sunday. 


&& 


Near term /through Thursday/... 
PA and New York remain between the northern branch of the jet and the southern 
branch. Hence there is a very mild wrly flow of air with rdging 
aloft. A weak frontal boundary will sag southward toward northern New York state late 
tonight and Thursday and spread some scattered high clouds around. Otherwise it 
will be mainly clear. 


&& 


Short term /Thursday night through Saturday night/... 
very little to talk about in the short term as a ridge of high 
pressure will continue to take form across the area. This 
will all occur ahead of a digging upper trough across the western 
US which will lead to our next batch of weather towards the 
conclusion of the weekend. In any event...building heights along 
with warming 850 mb temperatures will allow afternoon high temperatures to 
remain well above normal through the period. Each day will allow 
for slightly warmer conditions as a 850 mb thermal ridge in advance 
of a weak surface low passing to the north sets up across the area by 
Friday. The only main concern with going temperature grids will be Friday 
afternoon across the lake plain where a weak frontal boundary 
attached to the previously mentioned surface low may encroach across 
the area. If this occurs...westerly flow behind the front for a 
may lead to slightly cooler conditions (mid/upper 50s as opposed 
to low 60s). Other than that...stalled front will quickly lift 
north of the area on Saturday with southwesterly flow expected to 
return area wide. Downsloping winds combined with warmer warm 
temperatures aloft and a well mixed atmosphere should allow for low/middle 
60s area wide by Sat afternoon with some isolated locations 
possibly approaching 70 in the valleys! 


&& 


Long term /Sunday through Wednesday/... 
main concern during this period will be a strong cold front that 
has been advertised to pass Sun night/early Monday. Unfortunately 
all the model agreement that we had with yesterday/S 12z runs is 
no longer as today/S 12z GFS/Canadian Gem are now trending faster 
than the 00z European model (ecmwf). That said...main reason for this is that the 
slower European model (ecmwf) develops a closed middle-level low across the Southern 
Plains/western tenn River Valley on Sat as the previously mentioned deep 
trough ejects out of the Southern Plains. Meanwhile the 12z GFS/Gem 
maintains an open wave through as it progresses east within the 
southern stream. That said...waited all morning to see the new Gem 
as initial thoughts were that that 12z GFS was out to 
lunch...however have been forced to reanalyze this with the 12z 
Gem. That said...have trended slightly faster and have made a 
concentrated effort to not totally discount the slower 00z European model (ecmwf). 
In response to this...have lowered afternoon high temperatures on sun as 
GFS/Gem now suggest front will occur during the day as opposed to 
Sun night/early Monday. Additionally...have increased probability of precipitation on sun as 
regardless of what model you choose...all are suggesting a rather 
healthy dose of rain as the front passes through. Still not overly 
concerned for thunder for the time being as very little 
instability is expected ahead of the frontal boundary...which will 
be further realized with an earlier frontal passage based on lack of daytime 
heating. So for now...have decided to take to conservative approach 
with hopes that subsequent model runs will help pin down the 
details a little better. 


Strong cold advection still expected behind the cold front for Monday 
with 850 mb temperatures decreasing to -8 to -12c range by 00z Tuesday. Have 
maintained -ra/snow mention through the day on Monday with wrap around 
moisture expected. -Sn may persist into Tuesday night ahead of a 
secondary cold front that is advertised to move through Monday 
night/early Tuesday. Moderating trend then expected by midweek as high 
pressure across the southeast slides off the East Coast and 
southerly flow returns. 


&& 


Aviation /23z Wednesday through Monday/... 
VFR conditions through tomorrow as high pressure continues to 
influence the weather over the Middle Atlantic States. 


Winds will diminish to light and variable tonight. Tomorrow they 
will range from light and variable to out of the north around 10 kts. 


Outlook... 


Wednesday to Sat...VFR. 


Sun...VFR. Showers and MVFR restrictions possible late in the 
day. 
Monday...VFR/MVFR rain showers 


&& 


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


&& 


$$ 
Synopsis...cmg 
near term...djn 
short term...cmg 
long term...cmg 
aviation...sli