FXUS61 KCLE 280014
Area Forecast Discussion
National Weather Service Cleveland OH
814 PM EDT Thu Apr 27 2017
Strong low pressure over the northern Great lakes will move
across eastern Canada and the associated cold front will move east
of the area early tonight. High pressure will build across the area
tonight into Friday. A warm front will develop over the lower
Ohio Valley Friday night and lift north of the area on Sunday.
Another strong low pressure system will develop over the
Mississippi Valley on Sunday and push a cold front across the
area late Sunday night and Monday.
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Received numerous reports of small hail with the thunderstorms
this afternoon. Showers and thunderstorms will shift east of
the Pennsylvania counties by around 9 PM and the threat for any
stronger thunderstorms is low at this point. Skies have been
clearing behind the cold front except in far northwest Ohio
where stratocu has spread back in associated with the low level
wrap around moisture. Subsidence behind the front will limit the
expansion of stratocu overnight but we will see high clouds
arrive from the west so will continue with skies becoming partly
Previous discussion...Plenty of subsidence following the front
and the stratocumulus out west seems flat and diurnal looking
and we should see clearing spread across the area tonight. The
air mass is seasonable (I keep having to remind myself that it
is April) and with winds lightening before daybreak we should be
able to sneak down into the mid 40s in most areas with some
lower 40s in the cooler spots. high clouds will begin to
increase toward daybreak which may keep the bottom from falling
out on temps.
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY NIGHT/...
The fast flow aloft will redevelop as the trough lifts out on
Friday. Hard to get excited about the prospects for any significant
showers, at least for Friday. Frontogenetic forcing will slowly
increase and the jet is slowly progged to lift north across
the Great Lakes as we go into Friday night and the weekend. Upward
motion will likely increase in the entrance region of the jet.
Friday may be one of those days where radar echoes increase but it
takes a while for much of anything to reach the ground. Will have a
small chance of showers, mainly across northwest Ohio later in the
day. The wind field in the mid and lower layers is progged to
increase significantly Friday night and the threat of showers and
thunderstorms will increase as a short wave moves east in the
fast flow. The GFS develops a surface low over the lower Great Lakes
early Saturday while the ECMWF just drifts the front north and then
south again. In any case, temperatures near Lake Erie could
slide back down Saturday afternoon as the flow comes around more
from the north, the type of pattern where Toledo never does warm up
during the day.
The ridge builds on Sunday and it looks as if the warm front will
move north. Temperatures should shoot up in the south flow as 850 mb
temperatures are progged to rise to 16C or so. Not quite as
confident farther north at Toledo and Erie where the warm air may
arrive slightly later in the day so will hedge a bit on
The cold front will approach from the west later Sunday n night or
early Monday morning from the west and the chance of showers and
thunderstorms will begin to increase again. Sunday night will be a
warm night ahead of the front.
.LONG TERM /MONDAY THROUGH THURSDAY/...
The main upper trough over the US will set up over the MS river
valley into the Great Lakes thru the period. S/W's rotating thru the
upper trough will induce surface lows that move thru the region
Monday and again by Thu night while a front remains near the area
thru the period. Expect good chances for shra/tsra Mon then a lesser
chance for Mon night thru Thu. Temps will start out near normal on
Mon then trend below normal for Tue thru Thu.
.AVIATION /00Z Friday THROUGH Tuesday/...
Cold front on the OH/PA border and will move east of the area
within next hours or so taking all the convection with it. MVFR
wrap around will spread over the entire area overnight. Gusty
West winds will gradually diminish after sunset.
Conditions gradually improve to VFR Friday...but more showers
and TSRA expect Friday night.
OUTLOOK...Non-VFR at times in showers and thunderstorms Sat through
Mon then just showers Tue.
A cold front crossing the lake this evening will veer winds more to
the west while wind speeds should stay just under that needed to
produce sca conditions. Weak high pressure moving across Ohio should
diminish the winds late tonight and cause a backing to mainly south
for Fri as the front pushes back north of the lake briefly before
shifting back south across the lake Sat. Winds will veer to north
then ne sat into Sat night and increase enough to produce sca
conditions for a while into Sun until the front moves back north
thru the lake turning winds to south.
South winds will increase Sun night to 30 knots then turn sw then
west as a deep low passes by and pulls a series of cold fronts
across the lake Mon. West winds could be near gale force on Tue as
cool air pushes across the lake.