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FXUS61 KBGM 210215

Area Forecast Discussion
National Weather Service Binghamton NY
1015 PM EDT Fri Sep 20 2019

High pressure will bring fair weather and warm days to central 
New York and northeast Pennsylvania through the weekend. Expect
valley fog each morning this weekend, then sunny or mostly 
sunny skies. A weak front will bring scattered showers and 
perhaps a stray thunderstorm into the region on Monday.



1010 PM UPDATE...

Very quiet weather continues this evening. Just some minor
updates to the temperatures and winds. Expect valley fog to
begin to form once again after midnight. 

Previous discussion continues below. 

Quiet, fair and warm weather will dominate the near term period
as high pressure remains overhead. Only minor concerns will be 
for more valley fog (locally dense) late tonight into Saturday 
morning and cool overnight temperatures. Undercut NBM/Superblend
guidance by a few degrees based on the past few nights and 
another efficient radiational cooling set up. Now have forecast 
lows in the 40s, except for some low 50s both in the Finger 
Lakes and in the Wyoming Valley region. Still may not be cool 
enough if skies remain clear and winds light.

Then, latest guidance is indicating just a bit of instability 
and moisture sneaking into Steuben County Saturday afternoon as 
a weak shortwave disturbance drops down from Ontario. Added in a
slight chance for a stray shower or storm to western Steuben 
County to account for this. Otherwise, dry and mostly sunny 
with highs well above average in the upper 70s to lower 80s.

Dry Saturday night and not as cool with a steady south wind
developing. Could still see some patchy valley fog, but the 
wind may allow for more mixing. Partly cloudy with lows in the 
50s east, and lower 60s west of I-81; a bit more humid.


A strong ridge of high pressure will still in place on Sunday. 
The high pressure system will temporally shift east in response 
to an approaching cold front from the Great Lakes. The main 
change with the weather is that winds will become more southerly
and southwesterly bringing in milder air. Given the recent 
dryness and what modeled 925 mb temperatures it could get quite 
warm on Sunday with highs likely warmer than most of the 
statistical and blended data would indicate with highs in the 

The front will provide some lift but with very limited moisture.
It should be enough though for some showers to be around late 
Sunday night through Monday night. QPF continues to trend lower 
with this front as the modeling is keying more and more on the 
dry air in place that will take a while to moisten up. Modeled 
cape Monday afternoon and evening is still around 100 J/KG so a 
couple of rumbles of thunder can not be ruled out. Cloud cover 
will keep temperatures up in the 60's Sunday night and highs in
the 70's to around 80 on Monday. 

Behind the cold front, winds shift to the northwest. This will bring 
southward some moisture off the Great Lakes. Blended model data here 
appears too optimistic with the amount of clouds as this is usually 
a case where most of our region gets a cloudy day. A spotty shower 
or two in the Lake Effect regions is possible as well. Cooler 
air will advect in as well with temperatures back down into the
50's and 60's Monday night and Tuesday.


Model solutions diverge towards the middle of the week, but 
they are hinting that another frontal system could affect the 
region by the end of the week, but major timing errors exist at 
this time. Would not be surprised if this next front gets 
delayed until Friday and that it will be a fairly dry front with
little rainfall, as it is going to be very difficult to break 
down the broad ridge that will be in place over the Eastern U.S.


Mainly VFR conditions are expected at all terminals through this
TAF period. As is usual this time of the year, the one exception
will likely be at KELM, where IFR and occasional airport 
minimum visibilities are expected due to valley fog. Greatest 
confidence in seeing visibilities less than 1/2 mile is between 
10Z and 13Z. After 13Z, the fog will gradually dissipate, 
leading to VFR conditions once again after 14Z. 

Winds tonight will be light and variable before becoming mainly
west-southwesterly at less than 5 knots during the daylight 
hours on Saturday.

Saturday night through Sunday...VFR except late night/early 
morning valley fog expected for at least KELM; possibly KITH and
KBGM for brief periods as well.

Sunday night through Tuesday...Mainly VFR, but some restrictions
possible in showers as front crosses, especially Monday 
afternoon and evening.

Wednesday...VFR conditions likely with high pressure building 
in. May see some patchy fog at KELM in the morning.





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