Scientific Forecaster Discussion
fxus61 kcle 302001
Area forecast discussion
National Weather Service Cleveland Ohio
401 PM EDT sun Apr 30 2017
a warm front along the South Shore of Lake Erie will move north
tonight. Deepening low pressure over the plains will move north
to Wisconsin Monday and Ontario on Tuesday. The associated cold
front will move across the local area on Monday. Cooler and
blustery weather will spread across the area behind the cold
front. Another strong low pressure system will develop by
Thursday in the lower Ohio Valley.
Near term /until 6 am Monday morning/...
have given up on getting the warm front offshore east of
Cleveland. The lake breeze has enhanced the northeast flow such
that it will be locked in until the daytime heating ends. Winds
will come around from the south tonight and Erie will hit its
high temperature sometime between Sundown and midnight. Toledo
has a shot at the warmer air as there will be showers/storms
late this afternoon and evening that could mix down the south
Other pop-up showers/storms will continue late this afternoon
and evening. Dcape is high to the south and east and will have
to watch the storms skirting Canton, Youngstown and Meadville
for localized wind gusts.
The south wind will lose some of the gustiness tonight but the
low level jet will increase so winds will increase again later
tonight especially as the showers approach ahead of the cold
front in the predawn hours. The onset of the showers could
potentially mix down the higher winds and will have to keep an
eye on things Monday morning.
Short term /6 am Monday morning through Monday night/...
the showers will likely out run the front on Monday as the flow
aloft is south-southwest. New showers and thunderstorms will redevelop east
of I-77, perhaps along the Route 7/11 corridor from ytown to
Ashtabula or just east of there. The highest instability will
likely be farther east in central PA and upstate New York but will
have to monitor the development Monday afternoon. Stronger
winds will mix down behind the front and Monday will become a
windy day especially from around the I-71 corridor west across
Northwest Ohio. Cold advection will develop but it will remain
relatively mild for may 1st with highs from the upper 60s to
the mid 70s.
A few wrap around showers with the trough aloft will develop
later Monday afternoon and evening. The majority of the showers
will probably occur Monday night. Cooler Monday night. Forecast
lows near guidance in the 40s.
Long term /Tuesday through Sunday/...
lingering wrap around moisture will lead to a chance for a few
showers Tuesday afternoon as the upper level trough moves off to the
northeast. The best chance will be across the northern half of Ohio
into northwest Pennsylvania. The chance for showers will come to an
end Tuesday evening into Tuesday night as a surface high begins to
nudge in from the west. Tuesday afternoon will be windy once again
with wind gusts around 35 to 40 mph expected across the western half
of Ohio, and only slightly weaker winds farther east.
The high will be over the Great Lakes region Wednesday, and this
should keep most everyone dry through the day with much calmer
winds. It's possible a few showers could make it into far southern
areas by late afternoon, but that will be more likely after dark.
A low will be moving eastward near or just south of the Ohio River
Thursday. This will mean widespread rain for most everyone. Far
Northwest Ohio will be on the edge of the rain shield, so have lower
pops in that area. Winds will turn out of the east and northeast as
the low moves off to the east later Thursday. Winds then turn more
northerly Friday and Friday night and will turn out of the northwest
for the weekend. Gusty winds are expected Friday, and possibly
Thursday as well. The strongest winds will be near the Lakeshore and
across Northwest Ohio. The upper-level low will likely stall out
somewhere in the region Friday into the weekend. This would mean
continued rain chances through this period. Where exactly it stalls
out will play a key role in where the best chance of rain will be,
so for now just have chance pops everywhere until we can get a
better feel on where exactly it will stall out. Temperatures will be
below normal the entire period.
Aviation /18z Sunday through Friday/...
the warm front remains near the South Shore of Lake Erie
reinforced by the lake breeze. It will likely take until early
tonight to get the wind to shift from the south at Keri. The
wind direction at ktol is also tough. There are showers in the
vicinity of ktol and thunderstorms from Indiana will likely
reach ktol late this afternoon which may be enough to shift the
wind to a southerly direction. Elsewhere, a few pop up
showers/storms are possible, mainly at kcak and kyng this
The cold front from the west will reach Northwest Ohio early
Monday morning. Cannot rule out convection tonight ahead of the
front but given the lack of confidence did not mention anything
in the taf forecasts until the prefrontal showers/storms arrive
from west to east Monday morning.
South winds will be gusty at times this afternoon and the
gustiness will continue at time tonight and become even stronger
Outlook...non-VFR and scattered showers possible Monday through
Tuesday night and again Thursday.
east to northeast winds continue on the lake. Marginal small craft
conditions continue and will let the headline go till later this
morning. Winds will eventually flip to a more southerly direction
but that probably won't occur till sometime this evening. A cold
front is still on track to cross the lake on Monday. Southwesterly
wind behind the front will become westerly on Tuesday. There will
be a good push of cold air behind the front and speeds will come up.
Will likely need another prolonged period of small craft headlines
beginning sometime Monday night and likely continuing into
Wednesday. Winds will flip to an easterly direction on Thursday in
response to the low entering the lower Ohio Valley.
Marine...Small Craft Advisory until 10 PM EDT this evening for