CLE issues Area Forecast Discussion (AFD) at Dec 27, 6:50 AM EST872
FXUS61 KCLE 271150
AFDCLE
Area Forecast Discussion
National Weather Service Cleveland OH
650 AM EST Fri Dec 27 2024
.SYNOPSIS...
Low pressure will lift out of the lower Mississippi Valley and
into the northern Great Lakes through tonight, lifting a warm
front across the area. Another area of low pressure will lift
out of lower Mississippi Valley across the Ohio Valley and into
the eastern Great Lakes Sunday into Monday.
&&
.NEAR TERM /THROUGH SATURDAY/...
Low pressure over Arkansas early this morning will lift north-
northeast into the upper Mississippi Valley and western Great
Lakes through Saturday. A warm front will lift northeast across
the local area late this afternoon or this evening ahead of the
low. A cold front will approach from the northwest Saturday
evening, but likely won't make much headway into the local area
with the next low pressure taking shape to the southwest before
the cold front can push into the local area.
In terms of sensible weather impacts, clouds will thicken and
lower this afternoon and evening as isentropic lift increases
ahead of the approaching warm front. Some showers likely spread
in from the west/southwest this afternoon and evening. Showers
will generally be on a weakening trend as they push into our
area through this evening, owing to a retreating shortwave ridge
axis aloft and downsloping southeast flow. Still, anyone can see
a light amount of rain late tonight and tonight across the area.
Heading into Saturday we get into the warm sector south of the
warm front as a mid-level dry slot wraps in. This should yield a
mainly dry day, though with some warm air/moisture advection
returning from the south during the afternoon keep low POPs and
mostly cloudy skies in the forecast. QPF values have trended
lower for the period, now generally <0.10" through Saturday.
Highs today will warm into the upper 40s and lower 50s. Lows
tonight will mainly stay in the 40s, with some 30s possible east
of I-79 in PA. Highs Saturday push into the mid 50s to around
60. South-southeast breezes will pick up a bit this afternoon
into tonight. Non-hazardous, though some 20-30 MPH gusts are
possible, especially across Northwest and North Central OH along
with the downsloping locations along the eastern lakeshore.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
Potent upper-level trough over the lower Mississippi Valley Saturday
night will strengthen as it lifts north-northeastward across the
area Sunday and Sunday night. The attendant surface low deepens to
sub-1000mb as it traverses the forecast area Sunday. Strong synoptic-
scale forcing/lift should result in areawide rain quickly
overspreading the area after 06Z/Sun with near continuous, areawide
rainfall through at least the entire morning Sunday. Rain is likely
to continue into the afternoon/evening hours, however most global
models have a dry slot briefly developing, so expect some breaks in
precipitation during this time frame, especially in the southern and
eastern part of the forecast area. Ensemble mean QPF is forecast to
be around 0.6-1" when all is said and done (locally higher/lower
amounts of course). Not overly concerned with flooding but areas
that receive greater than an inch could see some nuisance flooding
(e.g. minor standing water in low-lying areas).
Some model guidance develop low instability within the warm sector
all the way northward to near the low pressure center. This is most
aggressively depicted by the NAM, though is it at least hinted at by
most other global models. This could add a convective element to
showers that develop along and ahead of the cold front Sunday
afternoon/evening. For now, didn't include thunderstorms in the
forecast yet but it's possible this may be needed in future
forecasts if this trend continues. Any amount of instability this
time of year is worth keeping an eye on, simply because it is almost
always accompanied by a lot of deep-layer shear. In our case,
instability is predicted to be quite low (generally 300 J/kg or
less) though this tends to be enough for marginal, isolated severe
weather when in the presence of strong synoptic-scale lift and low-
level wind speeds (forecast 40-50 knots at 850mb). SPC Day 3 severe
thunderstorm outlook does have a marginal risk just clipping our
forecast area in Stark/Holmes counties. Strong, gusty winds are the
most likely weather hazard if thunderstorms do develop.
As this low lifts into southeastern Ontario Sunday night, moisture
wrapping around this low is likely to lead to at least lingering
precipitation Sunday night through Monday morning. Latest global
model ensembles have trended a bit cold on the backside of this low,
especially the ECWMF ENS, with the 0 C line wrapping in a bit
quicker. This isn't reflected in the current forecast quite yet, but
it's possible that some of this precipitation could fall as a
rain/snow mix at times Sunday night into Monday morning. High
pressure will build in Monday afternoon into Monday night.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
The active pattern continues as another low pressure system (of
~1000 mb) is expected to move east across the Ohio Valley Tuesday
into Tuesday night. Light to moderate rainfall is expected with
average QPF around 0.25-0.5" with this system. A more notable
pattern change is expected thereafter, with temperatures crashing
down to near normal January temperatures Wednesday onward. Some of
the "system precipitation" could transition to rain/snow mix and
then some light snow on Wednesday before we transition to lake
effect snow for the snowbelt of Northeast Ohio and Northwest
Pennsylvania Wednesday night and Thursday. There is a pretty good
chance for "shovelable snow" of 2" or greater for a good portion of
the snowbelt during the timeframe and into the weekend.
&&
.AVIATION /12Z Friday THROUGH Tuesday/...
Mainly VFR continues through most of today. A warm front moves
through this evening, bringing showers along and ahead of it and
lower ceilings along and behind it. Confidence in vsby
restrictions is low, but confidence in ceilings falling to MVFR
from west to east is higher. Dry downslope flow will slow the
advance of lower ceilings some at eastern sites. Guidance has
backed off a bit on IFR ceiling potential this evening into
tonight behind the warm front. A dry antecedent airmass and
downsloping southeast flow may make it hard for ceilings to get
too low tonight. While potential still remains, currently don't
have IFR in any TAFs as confidence in it is too low.
Winds will be out of the southeast and remain under 10 knots
this morning before increasing to 8 to 14 knots this afternoon
and tonight. With a strong low-level jet moving overhead for
several hours this evening into tonight as a low-level inversion
develops, elected to add low-level wind shear to the TAFs from
CLE and CAK points west. The low-level jet is a bit weaker to
the east.
Outlook...Non-VFR likely in occasional showers and lower
ceilings through Sunday night. Additional non-VFR possible in
rain on Tuesday.
&&
.MARINE...
East to southeast winds continue today before a warm front lifts
north across the lake tonight, with flow becoming south. A low moves
northeast across Lake Erie on Sunday, with a great deal of
uncertainty in the wind and wave forecast Sunday, though there is a
pretty good chance for impactful weather. Confidence increases in
stronger west to southwest winds of 20 knots or greater Sunday night
into Monday before high pressure builds in Monday afternoon into
Monday night. Low pressure expected to build into Ohio Valley on
Tuesday with east to northeast flow developing on Lake Erie.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...None.
PA...None.
MARINE...None.
&&
$$
SYNOPSIS...Sullivan
NEAR TERM...Sullivan
SHORT TERM...Saunders
LONG TERM...Saunders
AVIATION...Sullivan
MARINE...Saunders
Source:
CLE issues Area Forecast Discussion (AFD) at Dec 27, 6:50 AM EST---------------
If I'm using your data in a way that is against your terms please email the team at "threatweb@pupswoof117.com"! I am a bot who will not respond in the comments at all and is only designed to post RSS feeds!
