475
fxus61 kcle 311941
afdcle
area forecast discussion
national weather service cleveland oh
341 pm edt mon aug 31 2026
.what has changed...
a heat advisory has been issued from a cleveland-akron-wooster-
mt vernon line points west from tuesday afternoon through
wednesday.
&&
.key messages...
1) it will be humid with a couple of rain chances through midday
tuesday, but with limited overall impacts/hazards.
2) hot and humid conditions are expected tuesday afternoon
through thursday, with peak heat index values ranging from the
mid 90s to lower 100s and limited overnight relief.
3) an unsettled pattern with multiple risks for thunderstorms
is expected late tuesday through friday. there is considerable
uncertainty regarding the timing and placement of thunderstorms,
but severe weather and locally heavy rainfall are possible.
&&
.discussion...
key message 1...
a very warm and humid monday afternoon across the area with
temperatures ranging from the upper 70s in pa to the upper 80s
in marion and dew points in the upper 60s and lower 70s. low
impact weather is expected through tuesday morning, though do
note it will be a muggy night with lows mainly staying up in the
lower to mid 70s with dew points only slightly cooler than that.
a weak shortwave glancing the region may continue to cause a few
light showers (and perhaps a stray storm) across the area
through early this evening before exiting east-southeast.
another shortwave will glance the region late tonight/early
tuesday, which will combine with ongoing warm air/moisture
advection to spark some showers and possibly an isolated storm
late tonight into early tuesday. any showers will exit to the
southeast by midday tuesday.
key message 2...
meteorological fall technically starts on tuesday, but it will
not feel like it with a heat advisory in effect for a good chunk
of the forecast area. upper ridging will reach peak amplitude
across the central and eastern u.s. tuesday and wednesday,
before shifting southwest as troughing builds over the northeast
thursday and friday. a very warm and humid airmass (pwats
climbing to nearly 2.00" and 850mb temperatures topping out at
20-22c) will support what is hopefully the season`s last round
of excessive heat across the local area through thursday.
high temperatures will range from the mid 80s to lower 90s on
tuesday with dew points in the low to mid 70s. wednesday appears
to be the hottest day, with highs ranging from the upper 80s to
mid 90s with dew points in the upper 60s and lower 70s. thursday
will still be quite warm but trend a bit cooler farther north,
with highs forecast to range from the mid 80s to lower 90s with
dew points mainly in the lower 70s. there is some potential for
lingering cloud cover, afternoon convection, and a lake breeze
to keep far northeast oh and northwest pa slightly cooler on
tuesday. convection potential does add some uncertainty for
wednesday and thursday. current consensus is that any lingering
convection will clear early wednesday, with any renewed
activity largely holding off until after peak heating. thursday
appears to have the greatest potential for convection to keep
temperatures cooler than forecast.
arguments for the heat being hazardous/impactful include warm/
humid nights providing for limited relief, the multi-day
duration, and some school buildings not having air conditioning
across the area. so while forecast peak heat index values are
on the lower end for a heat advisory and there is some
uncertainty, opted for a heat advisory from the cleveland-
akron area points west for tuesday and wednesday where
confidence is overall the highest in peak heat index values
nearing or reaching 100 degrees both days. we may need to expand
the advisory east to include more of our eastern ohio counties
for wednesday, but these areas look a bit cooler on tuesday than
areas farther west so left them out for now. parts of the
advisory may need to continue through thursday, though
uncertainty regarding the timing of the cold frontal passage and
convective potential are too high to do that yet.
key message 3...
the local area will be located on the edge of a heat ridge
through much of the week as a front waivers to our north through
wednesday and pushes south thursday and friday. this will place
us in a potentially active corridor of weather for most of the
week, though overall confidence in the timing and location of
greater thunderstorm potential remains low. with that said, an
elevated mixed layer (eml) plume will lead to steeper mid-level
lapse rates atop very warm and humid low-levels, fueling
moderate to very strong instability across the area from tuesday
afternoon until the cold front tries crossing thursday into
friday. west-northwest flow aloft will also be moderately
strong, providing sufficient shear for organized and potentially
severe convection. precipitable water values climbing to
1.70-2.00" in this very warm environment will also support
torrential rain rates within convection and potential for heavy
rain/flash flooding with any training or repeated rounds of
convection through the week.
starting with tuesday and tuesday night, it`s possible much of
the afternoon and evening hours are dry as there is a distinct
lack of large-scale forcing during that time. however, there`s
good agreement in very strong and only weakly capped instability
developing tuesday afternoon/evening. there may be some triggers
for afternoon/evening convection, mainly in the form of a lake
breeze near the northeastern lakeshore and potentially a
differential heating boundary left behind by morning clouds/
showers. these boundaries may support a few storms developing
during the afternoon or evening, mainly across northeastern
portions of our area. greater potential for storms may arrive
overnight tuesday night into very early wednesday morning as a
shortwave glances the region, potentially sparking thunderstorms
upstream that track into the local area. the greatest overall
chances for storms late tuesday and tuesday night will be across
northern portions of the area (including lake erie, northeast
oh, and northwest pa) with chances diminishing to the southwest.
it currently appears that any lingering activity will exit
early wednesday, leaving a period of drier weather through the
day. a shortwave will approach and move through late wednesday
and wednesday night as the surface cold front approaches from
the north. the current forecast favors potential for isolated to
scattered storms to try developing late wednesday afternoon or
evening, especially along the lake breeze or any boundaries left
by earlier convection, with greater potential sagging in from
the north/northwest later wednesday night. will need to closely
monitor this progression as hi-res models that run out through
wednesday (such as the 12z rrfs) do offer some potential for
organized convection to arrive as early as wednesday afternoon.
the same general pattern persists on thursday and possibly even
for friday, though details become quite murky by then and it`s
possible the front clears at least parts of our area. the
general theme is that unsettled weather remains in the forecast
for thursday and friday with lingering potential for organized
and potentially severe convection along and ahead of the front.
the greatest concern will gradually shift towards our
southwestern counties thursday and friday. the hope is that
high pressure to the northeast presses in enough to push the
front out of the area this weekend. confidence in that scenario
is not high so some lower rain chances remain in the forecast
for saturday and sunday, especially farther south and west.
&&
.aviation /18z monday through saturday/...
isolated rain showers with vfr conditions are possible over the
next couple but should dissipate as they move southeast. light
rain showers could linger in northwest pennsylvania tonight but
otherwise vfr is expected. isolated to scattered showers could
develop tuesday morning approximately 11-15z with some better
chance at non-vfr occurring, though this is very low confidence
at this point.
outlook...several rounds of thunderstorms are possible across
northeast ohio and northwest pennsylvania tuesday through
wednesday night, with a better chance at showers and storms
elsewhere in the area thursday and thursday night.
&&
.marine...
broad southwest flow is expected as the warm front pushes northeast
of lake erie, and will continue through at least wednesday night
before a cold front moves south across the lake on thursday. there
are a couple periods that winds could briefly reach 20 knots though
small craft advisories are not expected at this time. through the
week, there will be multiple chances for thunderstorms, though
timing if very uncertain at this point. any thunderstorms that do
occur could become strong to severe with a good chance of producing
winds > 34 knots and hail > 0.75".
&&
.cle watches/warnings/advisories...
oh...heat advisory from 2 pm tuesday to 8 pm edt wednesday for
ohz003-006>011-017>021-027>031-036-037-047.
pa...none.
marine...none.
&&
$$
discussion...sullivan
aviation...saunders
marine...saunders