694
FXUS61 KCLE 040016
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
816 PM EDT Thu Apr 3 2025

.SYNOPSIS...
Low pressure moves off into Eastern Canada as a frontal boundary
wavers north and south over the Ohio River Valley this evening.
Low pressure systems will track northeast into the region
through the weekend bringing moderate to heavy rain at times.
Another low pressure will approach from the northwest on Monday
bringing much colder air and the potential for light snow to
start the week and high pressure will build in behind.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
730 PM Update...
Overall, no changes were needed with this update. The next
update may include modifications to PoPs depending on the
northward extent of the main precip shield, but would like to
monitor radar trends and ASOS/AWOS obs over the next couple of
hours before making adjustments.

Previous Discussion...
An upper level trough currently located over the western half
of CONUS will be slowly moving eastward as a strong jet and
accompanying LLJ push northward from the south into the Great
Lakes region. The LLJ will start to really get going late Friday
night with models showing a 50kt LLJ moving into the region
bringing ample moisture advection. The current break in the rain
will end late this evening as precipitation will return as the
boundary over the Ohio River Valley wavers to the north
overnight tonight. Most of the precipitation will stay in the
southern portion of the CWA, with areas south of U.S. Route 30
seeing between 0.25-0.50 inches of rain through Friday morning.
Areas north will see less than 0.25 inches of rain. There will
be drier weather during the day Friday, as the boundary drifts
back south. The next round of precipitation will return Friday
evening into the overnight hours as a low pressure system and
warm front move north across the region. The bulk of the
precipitation is expected to fall late Friday night with an
overall QPF expected to be between 0.50-1.00 inches during the
overnight hours. Areas west of I-71 will be closer to 1.00 inch
total during that time period with locally higher amounts
possible as well. With the rainfall received Wednesday night,
flooding of rivers, streams, and street flooding is a concern.
Will need to continue to monitor into the weekend. Temperatures
will stay mild through the period with highs in the low 50s on
Friday and overnight lows being in the mid to upper 40s.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Active weather continues into the start of the weekend, with a front
wavering across the northern Ohio Valley through early Sunday
before getting shunned farther to the southeast Sunday into Sunday
night. A weak shortwave and associated wave of surface low pressure
will be riding along the front across the area to start Saturday,
with another round of widespread rain and perhaps a bit of thunder
ongoing. We will see a bit of a break in the rain during the day
Saturday behind the low as the front pushes a bit to the southeast.
Another shortwave and associated wave of weak surface low pressure
will ride along the front Saturday night into Sunday, bringing
another round of rain...particularly across our southern counties. A
brief spell of high pressure and drier weather builds in late Sunday
and Sunday night as the front finally pushes far enough to our
southeast to allow dry air from the north to win out.

A modest severe threat may develop on the warm side of the front by
early Saturday afternoon amid a weakly unstable, strongly sheared
environment. There is some model disagreement on how quickly the
front pushes southeast and out of our area Saturday morning/early
afternoon, though a slower front would increase concern for severe
weather locally. Overall a rather conditional threat, and feel the
SPC Day 3 Marginal Risk (level 1 of 5) sufficiently covers it for
now. Damaging winds would be the main concern, with a non-zero
tornado threat owing to the strong low-level and deep-layer shear.

The greater concern for the weekend will be continued hydro/flooding
concerns. The current forecast has an additional 1.00-2.00" of rain
from Saturday morning through Sunday from approximately a Findlay to
Sandusky line points southeast, with the greatest amounts towards Mt
Vernon. There is some uncertainty regarding the northern extent of
the heavier rain potential, particularly Saturday afternoon and
beyond. The overall axis has shifted south slightly with this
forecast package, but is still enough rain to maintain river
flooding concerns through the weekend as it is. Will also need to
watch for localized flash or urban flooding with any training
convection on Saturday (if convection materializes before the front
pushes southeast), along with Saturday night if we get a quick hit
of 1.00"+ of rain as some guidance suggests. The Flood Watch remains
as posted along and west of I-77 until Sunday morning, and those
with flood-related concerns should continue monitoring rainfall
forecasts, river levels, and river level forecasts.

Highs on Saturday will range from the upper 50s in Toledo to the 60s
for much of the area, possibly touching 70 towards Canton and
Youngstown if the front is slow enough to push back southeast. Lows
Saturday night much chillier, mainly mid 30s to near 40. Highs on
Sunday will be stuck in the 40s, with a frosty night Sunday night
with lows in the upper 20s/lower 30s.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
A potent trough with a tap of lingering arctic air over Canada will
swing through the Great Lakes Monday into Tuesday. This
deeper/colder trough will lift out fairly quickly towards mid-week,
though general longwave troughing will persist over the Northeast
through the remainder of the long term, maintaining cooler than
normal conditions.

An arctic cold front (or at least an April version of one) will
blast across the area Monday afternoon/evening. A band of rain/snow
showers may accompany the front, with a quick blast of wind gusts
over 30 MPH along and just behind the front. There is good agreement
on 850mb temperatures plummeting to -14C to -16C Monday night into
early Tuesday with 700mb temperature bottoming out at -20 to -23C.
Over lake water temperatures of 2-4C, this yields fairly strong
instability over the lake for a brief window late Monday night into
Tuesday morning, with at least some lingering synoptic moisture to
at 850mb, possibly higher if the GFS/European are correct with a
more amplified trough. Given this, have at least a chance for snow
showers lingering in the snowbelt through Monday night into Tuesday
morning. Accumulating lake effect snow is not unheard of in April,
and if guidance doesn`t back off the depth of the trough the higher
terrain of the snowbelt could get an unwelcome (we are assuming
here) blanket of snow into early Tuesday. Accumulations shouldn`t be
heavy, but could easily be measurable and perhaps on the order of a
couple inches in the higher terrain. Locations outside of the
snowbelt should dry out quickly Monday night after the cold front
exits, though a few flurries may occasionally linger in the air
through early Tuesday anywhere in the cold/cyclonic flow...and any
lake effect should wind down/end quickly on Tuesday due to a
combination of the deep trough quickly departing and negative
diurnal influence on lake effect during the day this time of year.

High pressure should bring dry but chilly weather later Tuesday
through at least Wednesday. The next shortwave likely approaches
from the west Wednesday night or Thursday, though timing and
strength varies significantly on current guidance. This leads to a
gradual ramp up to 30-40% type POPs for rain by Thursday.

Temperatures will be a bit cooler than average Monday...much below
normal Tuesday...and gradually trending towards (but still not
getting back to) normal by Thursday.

&&

.AVIATION /00Z Friday THROUGH Tuesday/...
Rain will continue to overspread the area tonight, although
there is still some uncertainty in the northward extent of the
precip shield in addition to the timing of rain exiting the area
tonight/early Friday morning. Either way, there will likely be
periods of MVFR cigs/vsbys with a low-end chance of IFR vsbys
from roughly KMFD to KYNG and points south tonight (opted
against putting sub-MVFR conditions in the TAFs since confidence
is pretty low at this point). Showers will exit to the
southeast by 12Z Friday and dry weather is expected before rain
once again enters the area from the southwest towards the very
end of the TAF period.

Northwest winds will gradually shift to the northeast tonight
and expect wind speeds to remain below 10 knots through Friday
morning. Winds will likely increase to 6 to 12 knots from KCLE
to KMFD west and a few gusts to 20 knots cannot be ruled out
during the afternoon and early evening.

Outlook...Non-VFR ceilings will return across the region into
Friday with some non-VFR visibility possible in showers and
storms, mainly towards the southern part of the forecast area.
Non-VFR more likely areawide in showers and thunderstorms Friday
night into Saturday with non-VFR ceilings continuing into
Sunday. Additional non-VFR conditions possible in rain and snow
showers Monday into Tuesday.

&&

.MARINE...
West-southwest winds are brisk and gusty this afternoon. Small Craft
headlines continue from Cleveland points east through 8 PM this
evening. Winds are reaching the 20kt sustained criteria at times
farther west this afternoon and contemplated expanding the advisory,
though should be on their way down into this evening so held off due
to the brief/marginal nature of the conditions. Expect relatively
quiet marine conditions tonight into Friday. East-northeast winds
pick up to nearly 20 knots Friday night into early Saturday, and
could build waves enough to warrant a Small Craft Advisory for
western zones. Winds turn southwest and then northwest through
Saturday as low pressure passes by just to the south of the lake and
diminish to 10-15kt. Winds will remain onshore at up to 15kt through
Sunday and will maintain choppy conditions, though should be under
headline-criteria. Headlines will be needed as a strong cold front
crosses Monday afternoon/evening, ushering in strong northwest
flow.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Flood Watch through Sunday morning for OHZ003-006>011-017>021-
     027>032-036>038-047.
PA...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for
     LEZ146>149.

&&

$$

SYNOPSIS...23
NEAR TERM...23/15
SHORT TERM...Sullivan
LONG TERM...Sullivan
AVIATION...15
MARINE...Sullivan