604 
FXUS61 KBUF 071138
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
738 AM EDT Fri Oct 7 2022

.SYNOPSIS...
A sharp cold front is crossing the region this morning with showers 
spreading from west to east through today. Showers transition to 
spotty lake effect showers tonight through Saturday with most places 
staying dry into the weekend. It will be much cooler behind the 
front where temperatures peak well below normal through the weekend.

&&

.NEAR TERM /THROUGH SATURDAY/...
Surface low pressure across southern Quebec this morning will slowly 
track east today. The associated cold front extends from Ottawa to 
northwest PA and lays across western NY this morning. Winds 
have shifted to the west-northwest behind the front where light 
southerly winds persist across central and north central NY. The
front will move from west to east this morning. A cold airmass 
resides behind this frontal boundary and will spread across the 
eastern Great Lakes region today and tonight bringing well below
normal temperatures and spotty lake effect showers. 

An upper level trough just north of Georgian Bay will track east 
into Quebec today. Ascent in the mid levels combined with increasing 
moisture and strong low-level convergence will bring showers across 
the region this morning. Temperatures aloft are falling quickly
behind the front and lake enhancement is expected to northwest 
facing slopes immediately east of Lake Erie through daybreak and
east of Lake Ontario daybreak through mid-morning. Elsewhere, 
showers will be more spotty through the morning. The advertised 
cold airmass will spread across the relatively warm lakes today.
Temperatures at 850mb will likely fall to -2C by late 
afternoon. Showers will remain possible across the region 
through the afternoon with lake enhancement southeast of the 
Lakes. Moisture diminishes quickly behind the front which will 
negatively impact lake effect showers through the afternoon. 
Rainfall amounts will average 0.10-0.25 inches immediately east 
of Lake Erie and Lake Ontario with less than 0.10 inches 
elsewhere. Breezy today with northwest winds gusting to 20-25 
mph and gusts as high as 30mph near the southern Lake Ontario 
shoreline. High temperatures will likely be reached around 
daybreak today with temperatures holding steady or falling 
through the afternoon. Highs will range from the upper 40s to 
low 50s across far western NY to the mid to upper 50s east of 
the Genesee Valley. 

Another trough will swing across the eastern Great Lakes region 
tonight. Ascent and increasing moisture may kick up the intensity of 
lake effect showers this evening. No problem with cold air as cold 
air advection continues through most of tonight with 850mb 
temperatures reaching -5C by late tonight. Northwest flow will 
direct these showers southeast of the Lakes into Saturday morning. 
As surface temperatures fall into the 30s, some rain showers may mix 
with snow across the higher terrain into Saturday morning. Chilly 
tonight with lows in the low to mid 30s across the higher terrain to 
the low 40s near the shorelines and southeast of Lake Ontario. 

A strong area of high pressure over the middle Mississippi Valley 
will track eastward Saturday. The wind field will start to veer 
moving any lake effect showers northward through the day. Moisture 
is very limited so lake effect showers will be weak and spotty. By 
Saturday afternoon, southwest winds become well aligned with the 
eastern Great Lakes and lake effect clouds and bands may develop 
with the best chance east of Lake Ontario. Rainfall amounts will be 
light. Between lake effect showers, mostly sunny skies expected. 
Cool Saturday with temperatures in the upper 40s to mid 50s.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
A persistent longwave trough will still be in place across the Great 
lakes region as we open this period...but the good news is that it 
will be on its last legs. Chilly air within this trough will support 
some early season lake effect showers east of both lakes Saturday 
night into Sunday...esp across the North country where a little more 
synoptic moisture will accompany an environment with a cap of 6-8kft 
and low shear in the H8-9 layer. Will raise pops to likely in this 
area for MAINLY rain showers...while high chc pops will be in place 
E-NE of Lk Erie. Worth mentioning that the GEM looks far superior to 
most of the guidance packages for this...esp over the GFS which is 
suspiciously 'dry'. Over a half inch of rain will be likely in the 
vcnty of the Tug Hill Plateau. 

A pair of shortwaves will then push a weak cold front through the 
region Sunday night and Monday. Given the lack of baroclinicity and 
UL jet support...the bulk of the pcpn associated with this forcing 
will only support chc pops for rain showers...most of which will 
come within residual lake driven convection east of Lk Ontario 
Sunday night. Otherwise...Monday should feature improving conditions 
with gradual clearing.

High pressure centered over the Mid Atlantic region will then supply 
us with fair dry weather Monday night.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
A progressive ridge moving across and east of the Lower Great Lakes 
will support a wealth of sunshine Tuesday and Wednesday along with 
temperatures that will climb back above normal. 

The stretch of fine weather will come to an abrupt end Wednesday 
night and particularly Thursday when showers will accompany the 
passage of a strong cold front.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
A cold front is across western NY this morning and will track 
through the rest of the region through mid-morning. Winds have
become west-northwest across much of western NY. The front will
track east through the morning hours with a wind shift at KART 
by 15z this morning. Mainly MVFR across western NY with IFR
across the higher terrain including KJHW this morning. MVFR has
already moved into KART ahead of the front. Regional radar 
shows scattered showers along and behind the cold front western
and north central NY. These showers will cross western and 
north central NY through this morning however intensity should 
remain light to moderate with only a short period of potential 
visibility restrictions. 

MVFR restrictions will continue through today as the cold front 
moves east of the eastern Great Lakes region. Northwest winds will 
continue through the day with gusts in the 20-25kt range with the 
higher gusts near the southern Lake Ontario shoreline. A much cooler 
airmass will move overhead today into tonight and lake effect rain 
showers will persist into this evening. Local MVFR restrictions 
possible mainly at KJHW and KROC through tonight.  

Outlook... 

Saturday through Sunday night...MVFR restrictions possible in lake 
effect showers. 
Monday through Tuesday...Mainly VFR.

&&

.MARINE...
A strong cold front will cross the Lakes this morning with winds 
veering to the northwest. As this occurs...Small Craft conditions 
will quickly develop on area lakes. Small Craft Advisories for both 
lakes are in effect through this evening.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...Small Craft Advisory until 11 AM EDT this morning for LEZ040-
         041.
         Small Craft Advisory until 8 PM EDT this evening for 
         LOZ030-042.
         Small Craft Advisory until 11 PM EDT this evening for 
         LOZ043>045.

&&

$$

SYNOPSIS...HSK
NEAR TERM...HSK
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...HSK
MARINE...HSK