948
FXUS61 KCLE 131318
AFDCLE

Area Forecast Discussion
National Weather Service Cleveland OH
918 AM EDT Thu Jun 13 2024

.SYNOPSIS...
High pressure exits east through today before a cold front enters
from the west late tonight into Friday. High pressure builds back
over the region for the weekend before building east on Sunday.

&&

.NEAR TERM /THROUGH FRIDAY/...
Update...
Most of the forecast remains valid per latest trends in obs and
model guidance. Only change was to increase the high
temperature forecast slightly for this late afternoon. This is
based on the expectation of intervals of sunshine/daytime
heating complemented by low-level WAA amidst 850 mb temperatures
warming to the 16C to 18C range by late afternoon. Thus, highs
are now expected to easily reach the lower to mid 80`s in NW PA
and mid 80`s to lower 90`s in northern OH. The hourly
temperature, apparent temperature, and dewpoint forecast was
QC`d accordingly. Please see discussion below for further
details.

Previous discussion...
Departing high pressure and southwesterly flow will bring one last
dry and hot day to the region. High temperatures this afternoon rise
into the mid to upper 80s with near 90 degree temperatures along the
I-75 corridor. Dry weather ends tonight as an upper trough and
accompanying surface cold front enter the region. Low pressure
centered over Quebec will slowly drag this cold front across
Northern Ohio overnight tonight. Given the timing of the frontal
passage, upstream severe weather across Southern Michigan and
Indiana will likely weaken as we lose daytime heating with the
severe weather threat for our area conditional on the
thermodynamic environment. For now, portions of Northwest Ohio
remain in a Marginal (Level 1/5) Risk for severe weather tonight.
Overnight lows settle generally in the mid 60s tonight.

Upper trough and shortwave aloft will slowly exit the region through
the day on Friday and will keep shower and thunderstorm chances in
the forecast through Friday afternoon. Another area of high pressure
and a much drier air mass will move in place from the northwest
by the end of the near term period. Near to slightly below
normal high temperatures are expected on Friday behind the cold
front and as winds turn northerly. Highs will range from the
low to mid 70s across Northwest Pennsylvania and Northeast Ohio
to the low to mid 80s across western zones.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
The southern Great Lakes/Ohio Valley is in for a significant pattern
change that will take place during the short term forecast period.
Upper level trough exits to the east Saturday with one last day of
temperatures largely in the 70s with a few lower 80s across the CWA.
500mb heights begin to build over the southern Appalachians with
return surface flow as high pressure from Saturday exits the mid
Atlantic coast Sunday. 850mb temperatures on the rise during this
time frame, and temperatures Sunday will run about 10 degrees warmer
with 80s and lower 90s making an appearance in the western zones of
the CWA. Pretty much a dry period as well with no organized
convection or precipitation in the vicinity of the area. Saturday
will also see the last of the dewpoints in the 50s for likely some
time to come as they surge well into the 60s Sunday.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
The incoming airmass and pattern that favors stout ridging aloft
with 500mb heights in the 590s and 850mb temperatures over 20C will
become a dominant feature for the CWA heading into the long term and
likely beyond for at least a couple of days. Dewpoints well into the
upper 60s to lower 70s and temperatures consistently in the lower to
upper 90s will make things rather uncomfortable with the first heat
wave of meteorological summer. Long range operational models showing
that the ridge aloft will hold its grip on the area for the
foreseeable future. Rain chances in the long term will be very low,
if any, and do not see any organized system moving through. The dry
ground will make heating a bit more efficient as we go through
successive days without precipitation.

&&

.AVIATION /12Z Thursday THROUGH Monday/...
Dry with VFR conditions through the first half of the TAF period
as high pressure exits to the east. A cold front will approach
western sites late this evening bringing a dying line of
thunderstorms to KTOL/KFDY around 22Z-00Z this evening. As the
line continues to move eastward, thunder potential and shower
coverage decreases as we lose daytime heating. Have VCSH at all
other TAF sites reaching MFD/CLE around 04-06Z, CAK/YNG/ERI
07-08Z. Behind the cold front, expect for a brief window of MVFR
ceilings to move overhead. Not anticipating these ceilings to
linger through the day Friday as another high pressure system
builds overhead from the north.

South winds 5-10 knots will increase to 12-15 knots with gusts
to 18-23 knots mainly west of I-71 this afternoon. Wind speeds
diminish below 10 knots late tonight. Winds turn north by the
end of the TAF period but remain between 5-10 knots.

Outlook...Non-VFR is possible with scattered showers and
thunderstorms tonight into Friday morning.

&&

.MARINE...
Southwest winds today become northerly around 10kts late tonight
into Friday with the passage of a cold front across Lake Erie
tonight. Wave heights to around 2ft late Friday through early
Saturday before high pressure moves to the east and turns winds
easterly 5-10kts. Wave heights subside to 1-2ft for the western
basin and less than a foot for the central and eastern basins
Saturday. After Saturday, expect offshore southerly winds and wave
heights less than a foot in the nearshore waters and 1-2ft in the
open waters into early next week.

&&

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

&&

$$

SYNOPSIS...Iverson
NEAR TERM...Iverson/Jaszka
SHORT TERM...26
LONG TERM...26
AVIATION...Iverson
MARINE...26