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FXUS61 KBUF 150256

Area Forecast Discussion
National Weather Service Buffalo NY
1056 PM EDT Sat Sep 14 2019

High pressure over the Ohio Valley will continue to build across the 
Lower Great Lakes tonight. This will lead to generally fair weather 
through Sunday morning. After a couple weak disturbances bring 
some light showers Sunday afternoon into Monday, we can look 
forward to mainly fair dry weather with above normal 
temperatures for the majority of the new work week.


IR satellite showing mainly clear to partly cloudy skies across the 
region. Winds have fallen off substantially as high pressure over 
the Ohio Valley continues to build in through the night. Expect the 
typical patchy valley fog across the Southern Tier late tonight 
through around mid morning Sunday. Low temperatures will drop into 
the upper 40s across the higher terrain east of Lake Ontario, as 
well as a few of the deepest sheltered valleys across the interior 
Southern Tier. Elsewhere low temps in the 50s are expected. 

On Sunday, attention will be focused on shortwave now moving into 
the Upper Great Lakes that is currently bringing showers and some 
thunderstorms to these areas. This shortwave will track toward the 
Lower Great Lakes on Sunday with primary enhanced lift from upper 
level jet remaining north of Lake Ontario. Still, may see enough 
lift from the upper level forcing and approaching sfc wave of low 
pressure to generate some light showers, especially closer to Lake 
Ontario and the north country. Forecast soundings indicate deep 
moisture is limited, so will cap PoPs at just chance at this time. 
That said, some of the latest guidance is a bit more aggressive and 
trending a bit further south, so rain chances may need to raised if 
subsequent model runs continue this trend. Otherwise, after a mostly 
sunny start to the day, clouds will increase from NNW to SSE 
starting around midday. Temperatures will reach the low to mid 70s 
for all but the Eastern Lake Ontario region, where thicker cloud 
cover will move in earliest.


Water Vapor imagery this afternoon displays a compact shortwave 
nearing the northern border of MN. This feature will pass across the 
Great Lakes region this weekend, and be responsible for light 
rainfall across our region to open the period...which will last 
through the day Monday.

At the surface a weak surface low will pass across our region 
Monday, just ahead of the upper level shortwave. Convergence around 
this low, combined with the deepening moisture...and lift ahead of 
the shortwave should bring light rain showers across much of the 
region. Will continue with high chance to low likely PoPs. Overall 
rainfall will generally be around a tenth of an inch or less.

Behind the surface low Monday a northeast wind will develop. This 
flow will hang lower clouds, and linger some drizzle across 
WNY...with the flow also bringing resistance to temperatures more 
than 70F for all but the southern two tiers of counties. 

Surface high pressure to our west Monday night will bring drier 
air...that will clear out skies especially away from the lake 
shoreline. As a light northerly flow continues through the night, 
and under clear skies some inland areas of the North Country may 
approach the upper 30s for lows.

Tuesday and Tuesday night this high pressure over southern Canada 
and building ridge aloft will yield mainly clear skies...low 
humidity and comfortable late summer temperatures in the lower 70s.


Good agreement remains amongst model and ensemble guidance for a
long stretch of high pressure dominated conditions over the 
lower Great Lakes from midweek through at least the start of 
next weekend. The run-to-run continuity of the solutions from 
the ECMWF, Canadian, and GEFS all favor a slow-moving evolution 
of a sprawling ridge from the central portion of the CONUS 
toward the Great Lakes. This will favor dry conditions and a 
very slow run-up in temperatures during the week with a 
similarly slow run-up in humidity, as well.

Of notable exception continues to be the operational GFS-FV3. It
still has some ripple running atop the ridge on Friday which
would mar the otherwise spectacular week. It continues to be 
discounted owing to virtually no support from other model 


Generally VFR conditions will be found across the region through the 
TAF period. Only exception could be some IFR VSBY in typical patchy 
valley fog late tonight through mid morning Sunday over the Southern 
Tier. Mid level decks will begin to thicken from NNW to SSE around 
midday, lowering to low VFR decks by mid to late afternoon with the 
chance for a few showers, especially north. 


Sunday night and Monday...Mainly VFR in scattered showers.
Tuesday through Thursday...VFR.


Last Small Craft Advisory for eastern Lake Erie has been allowed to 
expire. Winds have dropped off and waves will follow suit with the 
normal lag behind. With this in mind, there will still be some 
choppy conditions on both lakes through the early overnight hours. 
High pressure will continue to build across the Lower Great Lakes 
from the Ohio Valley, allowing winds and waves to further subside 
overnight. Plan on light winds and negligible waves for Sunday.






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