044 
FXUS61 KBUF 250534
AFDBUF

Area Forecast Discussion
National Weather Service Buffalo NY
134 AM EDT Wed Mar 25 2020

.SYNOPSIS...
Low pressure will pass by to our south today, spreading plenty of 
clouds across the region. Most of the area will remain dry, with 
just a small chance of a few light rain and snow showers near the 
Pennsylvania state line this morning. A weak cold front will then 
cross the area Thursday afternoon and Thursday night with a chance 
of a few light showers.

&&

.NEAR TERM /THROUGH TONIGHT/...
IR satellite imagery showing mid/high clouds spreading into the 
eastern Great Lakes early this morning to the north of a weak system 
over the Ohio Valley. There are still some areas of low stratus 
leftover as well, mainly across the Southern Tier and Finger Lakes, 
and also east of Lake Ontario.

A mid level shortwave will track from the Ohio Valley to the Mid 
Atlantic today, with a weak surface low developing off the Virginia 
Capes by midday. The shortwave will continue to spread extensive 
cloud cover across the eastern Great Lakes today. DPVA ahead of the 
mid level trough and an area of frontogenesis to the north of the 
weak surface wave will pass through Pennsylvania this morning 
through early afternoon. The vast majority of associated 
precipitation will stay south of the area, although a few light rain 
or wet snow showers cannot be ruled out this morning near the 
Pennsylvania state line. Highs will reach around 50 on the lake 
plains of Western NY, and generally mid 40s elsewhere. 

The mid level trough and surface low will move well offshore by this 
evening, with a weak ridge surface and aloft building into the Great 
Lakes. Cloud cover will likely linger through this evening, with a 
brief period of partial clearing possible through the middle of the 
night before clouds begin to increase again ahead of a cold front 
moving into the central Great Lakes. The cloud cover and weak warm 
advection will keep lows in the upper 30s to around 40 on the lake 
plains of Western NY, with mid 30s in the cooler Southern Tier 
valleys and east of Lake Ontario.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Dry weather will last through early Thursday. After that point,
shortwave bringing a round of wet snow to parts of the Upper 
Great Lakes on Wednesday night will be heading toward the Ottawa
River valley. Though associated sfc low pressure system stays 
mainly north over Ontario and Quebec on Thursday, weak cold 
front tied to the low drops across the region Thursday 
afternoon. Expect scattered showers along the front with 
proximity to strongest forcing from the shortwave favoring the 
North Country for the most rainfall. Warm advection ahead of the
front will result in temps well into the 50s across the region.


Front that moves though on Thursday will settle to the Ohio Valley 
and Mid Atlantic states on Thursday night before stalling out. Looks 
quiet on Thursday evening before a weak low pressure wave rides 
along the stalled out front to possibly bring some rain showers to 
the south of Lake Ontario late Thursday night. Would expect showers 
to likely focus on southern edge of broad upper jet cresting the 
Ohio Valley and where moisture transport is maximized on the nose of 
elevated instability working in from the Southern Plains along the 
stalled out front. That said, there is a potential that good portion 
of showers late Thursday night into Friday morning may only push as 
far north as the Southern Tier. Recent NAM runs into this idea 
supported by ECMWF. GFS and Canadian farther north though. Key on 
this will be how far south the front settles on Thursday evening. 
Whatever occurs from this batch of showers, it will quickly exit the 
region by late Friday morning leaving mostly cloudy conditions for 
rest of the day. Weak north to northeast flow will result in cooler 
day than Thursday with highs mainly in the 40s to maybe near 50F in 
a few spots.

Friday night starts off dry, then as deepening low pressure system 
over the middle Mississippi River valley takes shape pushing a warm 
front toward Ohio Valley, expect showers to spread into western NY 
late evening through the overnight. Showers will be supported by the 
approaching warm front in addition to right entrance of jet from 
Ontario to the Mid Atlantic and another jet from the southern Plains 
to the central Great Lakes along with broad area of warm advection 
and moisture transport. Rain will be most widespread west of the 
Genesee valley but looks like North Country likely stays dry though 
through Friday night as high pressure persisting over southern 
Quebec keeps low-levels too dry for any precip.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
A couple of rounds of rain are expected Saturday and Sunday as a 
surface low traverses northeast through the Great Lakes. The first 
round of rain will result from the passage of the surface low's warm 
front on Saturday. Heading into Sunday, the associated cold front 
from the aforementioned low pressure system will sweep through the 
region again causing the next round of rain. While the surface low 
does appear to be filling in at this point, chances for rain are 
favorable due to the upper level jet dynamics and bountiful moisture 
in the region.

As we start the work week, the low pressure system will continue to 
weaken as it positions itself over southern Ontario and Quebec. 
Throughout Sunday night and Monday, the parent low will slowly give 
way to a secondary low developing off the coast of New England. This 
will keep the chances for some showers across the region, especially 
for far eastern areas in our region due to the developing low off 
the coast. As the low pushes further east, colder air will wrap 
around on the backside of the low Monday afternoon. A period of cold 
air advection combined with any lingering moisture may be conducive 
for some lake enhancement east of Lake Ontario resulting in rain and 
eventually snow Monday afternoon through Monday night. As compared 
to previous model guidance, the period of cold air advection appears 
to momentarily reach -6C at 850 mb and therefore depreciating the 
chances for any real snow accumulations in the higher terrain in the 
areas east of Lake Ontario. We'll have to keep an eye on this as it 
approaches. 

High pressure builds in Tuesday allowing for a brief period of dry 
weather.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
A few areas of low stratus will continue through the rest of the 
overnight, mainly from the Southern Tier through the Finger Lakes 
with areas of MVFR and high terrain IFR CIGS. Otherwise VFR will 
prevail for the rest of the area with thickening and lowering mid 
level clouds.

A weak wave of low pressure will pass to the south of the region 
today, spreading extensive cloud cover across the eastern Great 
Lakes. CIGS will continue to lower, but should stay mainly VFR 
across lower elevations. The higher terrain, especially from the 
Southern Tier through the Finger Lakes will continue to see areas of 
MVFR CIGS through the day. A few scattered light rain/snow showers 
are possible this morning down near the PA state line, otherwise dry 
conditions will prevail today. Weak high pressure will build into 
the eastern Great Lakes tonight. This will maintain VFR conditions 
in most areas, although some patches of MVFR to IFR CIGS may develop 
across the Southern Tier mainly east of KJHW as low level moisture 
over PA advects northward.

Outlook...  
Thursday...Mainly VFR but with a chance of rain showers.
Friday...VFR.
Saturday...Mainly VFR with a chance of showers across the western 
Southern Tier. 
Saturday night and Sunday...MVFR/IFR with rain likely.

&&

.MARINE...
East winds averaging around 15 knots will continue to produce choppy 
conditions on the western portion of Lake Ontario through this 
morning before diminishing this afternoon. A cold front will then 
cross the area Thursday afternoon and evening. Southwest winds will 
increase ahead of the cold front. This will produce choppy 
conditions on both lakes, although winds and waves may stay just a 
little below Small Craft Advisory criteria.

&&

.BUF WATCHES/WARNINGS/ADVISORIES...
NY...None.
MARINE...None.

&&

$$

SYNOPSIS...Hitchcock
NEAR TERM...Hitchcock
SHORT TERM...JLA
LONG TERM...EAJ
AVIATION...Hitchcock
MARINE...Hitchcock