Area Forecast Discussion
Issued by NWS Cleveland, OH
FXUS61 KCLE 291634
Area Forecast Discussion
National Weather Service Cleveland OH
1234 PM EDT Wed Mar 29 2017
High pressure will slide across the Great Lakes today and off the
east coast on Thursday. Low pressure from the southwestern
states will cross the Mississippi Valley by late Thursday and
pass over the local area on Friday. Cooler air will spread
across the area Friday night and Saturday as the low shifts off
the east coast.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Locations that cleared out early have seen a nice jump in
temperatures with the late March sun. Raised highs a few degrees
across most inland areas. Temperatures closer to Lake Erie
should peak soon and either hold steady or even start to drop
off as northeast winds increase slightly this afternoon.
Original "Today" discussion...
High pressure will cross the eastern Great Lakes with the flow
veering northeast. The northeast flow is a forecast challenge
since the wind will be off Lake Erie all day. Stratus remains
upstream all the way to near Lake Ontario so it will take a
while to flush out the clouds. Areas of northwest OH that have
cleared will likely see the low clouds return except perhaps the
Toledo area. The model soundings show a lot of subsidence by
the afternoon so we should improve. With the high sun angle,
once we start mixing and drying, we should see decent
dissipation of the clouds this afternoon. The days are long and
areas that see enough sunshine will see temperatures recover
into the lower 50s except 40s near Lake Erie. High clouds will
begin to increase mid/late afternoon especially northwest OH.
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
High clouds will continue to increase tonight. The east wind will
likely not become calm. Forecast lows will be a degree or two higher
Not a lot of confidence on the timing of the arrival of the showers.
The deep upper low from the southwest will begin to lift out while a
relatively strong jet slides across the Great Lakes on Thursday.
This will produce increasing divergence aloft while at the same time
warm advection increases as the low level jet begins to increase.
The boundary layer will remain relatively dry and the upper
low/trough will remain well to the west. Given the uncertainty,
the best option may be to increase the PoP from west to east
through the day. Most of the models hint that an initial line of
convection will push across the midwest and could reach western
Ohio Thursday afternoon although it will probably be weakening.
Will have the highest PoP across northwest Ohio in the afternoon.
The showers should spread east Thursday night into early Friday and
should be widespread with deep Gulf moisture, good dynamics and a
good low level jet. The best cape is elevated but there could
be thunder, especially as the occluded front approaches later
The occluded front should move across the eastern counties Friday
but the upper low will reach northwest Ohio and there should be
additional showers developing. The atmosphere will begin to turn
cooler and more stable although lapse rates will get steeper. Will
leave thunder out for now.
Cold advection will increase by Friday night into Saturday. The
north to northwest flow does not bode well for warmth and high
temperatures on Saturday will hold in the 40s in most areas.
Subsidence will increase but we could easily hang on to stratocumulus
especially across northeast OH and northwest PA.
.LONG TERM /SUNDAY THROUGH TUESDAY/...
Split flow pattern continues through the long term which means we
get a system across the Ohio Valley every few days. Monday
night/Tuesday appears to be the next after Canadian high pressure
resides across the Great Lakes Sunday into Monday. While there is
some timing/track differences...there is somewhat better than
average agreement/consistency with this system. Will take it and
bump up precip chances for Monday night in particular. Once again if
this take a track south of the lake then temperatures could vary
greatly with the cool flow off of the lake. Will have the inland areas
climb into the lower 60s for Mon/Tue.
.AVIATION /12Z Wednesday THROUGH Sunday/...
Trend for today will be for ceilings to lift and scatter this
morning. Stratus a mix of MVFR and IFR. Exact timing of
improvement difficult with breaks developing here and there.
Stratus will eventually disconnect from the lake and drift
inland. Dry air seems to be effective upstream and optimistic
about our improvement. Subsidence with high pressure extending
southward across the area should also help.
Otherwise VFR beyond this morning for the rest of the TAF
period with northeast winds coming around to the east by 06Z
OUTLOOK...Non-VFR developing Thursday and continuing into
Friday. Non-VFR possible through Saturday morning NE OH and NW
High pressure extends southward across the northern and eastern
lakes today keeping winds from a northerly direction. Tonight that
high shifts east and low pressure will be approaching the Ohio
Valley for Thursday/Friday. Winds will respond on the lake and we
will have an extended period of northeast winds from tonight through
Thursday night. With a long fetch and enough of a gradient,
winds/waves will likely be enough to initiate a small craft advisory
Thursday. An inverted trough extending northeast from the low may
bring winds around to the south at least across the east end of the
lake Friday, but as the low passes across central Ohio, winds will
come around to the north by Friday night/Saturday. High pressure
wraps up the weekend.