804 
FXUS61 KCLE 040824
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
424 AM EDT Fri Oct 4 2024

.SYNOPSIS...
A cold front will sag southeast across the area today, followed
by high pressure tonight through Saturday night. A stronger cold
front will blast through the area Sunday afternoon with cooler 
Canadian high pressure building in behind it early next week. 

&&

.NEAR TERM /THROUGH SATURDAY/...
Very pleasant and non-impactful early fall weather continues to
end the work week and start the weekend. A weak cold front will
sag across the area through this afternoon as a shortwave trough
zipping across the upper Great Lakes and into southeastern
Canada glances the region. High clouds are exiting to the east
this morning, with more widespread mid to high-level clouds
sweeping across the area in response to the shortwave and front
later this morning into this afternoon. Forcing and moisture 
are both limited. Held onto a brief window of 20% POPs along the
lakeshore from extreme northeast OH into Erie County PA this 
afternoon just behind the frontal passage, though overall toned
the POPs down a bit. Mainly clear conditions work in tonight 
and persist for Saturday behind the front. Winds will be light.

Highs today will be similar to or perhaps slightly (~1F) cooler
than Thursday's values, generally in the mid to upper 70s but
with lower 70s towards northwest PA. Lows tonight mainly in the
50s, but with a few outlying 40s likely and with places like
downtown Cleveland struggling to dip much below 60. Highs
Saturday will range from the upper 60s in PA and far northeast 
OH to the low to mid 70s across the rest of northern Ohio.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
High pressure retreats to the east on Saturday night as a fast 
moving trough approaches from the west. The pressure gradient 
increases overnight with southerly winds also ramping up, and 
lifting a warm front north across the area. While temperatures are 
forecast to climb into the mid 70s to lower 80s, we also expect to 
see an increase in moisture to the region with a narrow corridor of 
dewpoints approaching 60 degrees ahead of an approaching cold front. 
Deep layer moisture advection does occur ahead of an upper level 
trough that forces a cold front east across the area during the 
afternoon. Models suggest ML CAPE values of 1000+ along and east of 
the I-71 corridor. Breezy conditions will be in place on Sunday both 
ahead of and behind the front which may limit the rise in dewpoints 
to some extent due to mixing. Lowered/removed pops from a portion of 
the area during the morning as most of the area will be capped. As 
moistening occurs during the afternoon, the front will likely kick 
off at least scattered thunderstorms across the eastern half of the 
forecast area. The wind field also increases along the front with 0-
6km bulk sheer values of 40+ knots. Coverage of convection is 
somewhat in question across the central and western half of the area 
with the higher chances in the far eastern CWA. If we end up with 
convection, will need to keep an eye out for a few strong to severe 
storms during the mid to late afternoon. 

Conditions dry out quickly behind the front as a pretty impressive 
dry-slot wraps in through the 850-500mb layer. Westerly winds will 
gust to around 30 mph behind the front. Temperatures at 925mb fall 
from near 18-20C on Sunday to 9-12C on Monday. High temperatures 
behind the front will average about 15 degrees cooler on Monday as 
more fall-like conditions return. While we will see some lake effect 
cloud on Monday, it will mainly be confined to the far east given 
the return to a dry airmass with high pressure building into the 
Ohio Valley. 

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
An upper level trough will be over eastern Canada for much of the 
long term period with another shortwave trough crossing the eastern 
Great Lakes on Monday night. There is some disagreement with the 
placement of the trough during the extended which will impact 
temperatures and precipitation potential through the middle of next 
week. It looks like temperatures will tend to be slightly below 
normal. Overnight lows will be in the 40s most nights and we may 
finally see some frost in cooler locations. Given the generally dry 
airmass, only have some very low pops in the far eastern counties 
next week but a trough position centered closer to Lake Ontario per 
several runs of the ECMWF would yield a cooler and wetter
solution. 

&&

.AVIATION /06Z Friday THROUGH Tuesday/...
VFR is expected through the TAF period. There are some high 
clouds filtering through early this morning. Not expecting 
much/if any valley fog this morning, though will keep an eye on
the TOL area for a low probability (20%) chance for brief non- 
VFR visibility. A weak cold front will move through this 
afternoon, with mid to high-level clouds. Can't rule out a 
sprinkle near ERI but no restrictions are expected. Light and 
variable winds through this morning will turn north-northwest at
5 to 8 knots behind the front this afternoon, before turning 
more north-northeast and subsiding to 3 to 6 knots tonight.

Outlook...Non-VFR possible in isolated to scattered 
thunderstorms Sunday afternoon and evening. A few stronger wind 
gusts could be possible.

&&

.MARINE...
A weak cold front will cross Lake Erie today with light southerly 
winds veering to northwesterly. Overall winds will remain light 
today, then veer around to the northeast at 10-20 knots tonight, 
making for slightly choppy conditions on the central basin into 
Saturday. Winds increase to 15-25 knots out of the south on Saturday 
night as a warm front lifts north. This is quickly followed by a 
stronger cold front on Sunday with winds shifting to west and 
northwest at around 20 knots. A window of Small Craft Advisory 
conditions are likely Sunday night with waves of 3-5 feet from 
Cleveland to Erie. 

Beyond that time frame we get into a little bit of a pattern change 
as fall like conditions return with northwest winds and a trough 
over the eastern Great Lakes. The strength of this trough will be 
monitored. 

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.

&&

$$

SYNOPSIS...Sullivan
NEAR TERM...Sullivan
SHORT TERM...KEC
LONG TERM...KEC
AVIATION...Sullivan
MARINE...KEC