Scientific Forecaster Discussion
fxus61 kcle 240125
Area forecast discussion
National Weather Service Cleveland Ohio
925 PM EDT Fri Jun 23 2017
a cold front will cross the area this evening. A series of
troughs will cross the eastern Great Lakes and upper Ohio
Valley through the weekend and into Monday. High pressure will
then move overhead for the remainder of the work week with one
cold front sagging southward nearing Lake Erie Thursday into
Near term /until 6 am Saturday morning/...
still a little light rain at cak, yng and Mt Vernon, but the
front is still west of mfd. So cut pops to chance pops in the
east and ended mention of rain in the west. Tweaked overnight
lows up a degree or two as the clouds are a little slower to
erode. No other changes for the 930 update.
the widespread heavy rain threat has pushed south of the area,
with light to moderate rain remaining across the southern half
of our County Warning Area to start the evening. But the cold
front remains across far Southeast Michigan/Northwest Ohio and with
soupy airmass, localized heavy rain still a threat this evening.
Just enough instability for a few thunderstorms as Northwest Ohio
has been able to warm the best this afternoon. All precip
should be east of the area by about 3am. Cooler tonight with
upper 50s across the west and inland northwest PA and lower 60s
Short term /6 am Saturday morning through Monday night/...
a broad upper level trough will encompass the Great Lakes and
Ohio Valley region for this weekend bringing temperatures down 5
to 10 degrees below normal. A series of surface troughs will
pass, each brining somewhat cooler air to the area each time.
Monday will be the coolest with 800 mb temperatures around 5c or 6c.
Will have a number of locations which will remain in the 60s
Monday. Lows each night will dip into the 50s. As far as
precipitation GOES, one trough crosses Saturday. There likely
will not be enough moisture with it and will keep the mention of
precip out of the forecast. A more pronounced trough crosses
Sunday and we should have a daytime peak in instability showers
as lapse rates steepen. Same GOES for Monday. Will have best
chances each time across northeast Ohio/NW PA.
Long term /Tuesday through Friday/...
not many changes to the long term today. The period will start out
unseasonably cool with highs Tuesday at least 10 degrees below
normal. There could be some instability showers in the morning in
the east but drier air should win out by afternoon. The high
responsible for the drying will move off to the east on Wednesday.
This will allow another strong storm system to drop over the
northern lakes. This low will pass well to the north on Thursday
with a trailing front pushing south over the area. This will result
in scattered showers and thunderstorm chances beginning Thursday.
The front will stall over the area by Friday resulting in continuing
precip chances. Overall...the models are in fair agreement with
this scenario. Temperatures will be back to near normal by Thursday
Aviation /00z Saturday through Wednesday/...
not much rain left as the drier air begins to press across the
area and subsidence increases. The cold front is shallow and is
near the Lake Erie shore this evening with MVFR ceilings
associated with the front. The front will drop across the
forecast area tonight and ceilings should improve to VFR from northwest
to southeast. Winds will become westerly.
Cumulus will develop on Saturday. A short period of MVFR
cumulus is possible but it would likely last no longer than an
hour or two and given the low confidence, did not include it in
the taf forecasts. A VFR ceiling should develop (bkn040-060) by
Saturday afternoon. West winds will become gusty.
Outlook...chance of brief MVFR in showers Sunday into Monday
with a cold front and trough aloft.
a cold front will sag south across the lake this evening causing the
flow to become west to northwest. A brief period of Small Craft
Advisory conditions (waves about 4 feet) will develop this
evening behind the front but it should be short lived. The west
flow will continue most of the weekend. It looks like speeds
will increase a little late Saturday. Do not think we will need
a small craft headline but this is something that will need to
be watched. Westerly flow is also expected Monday. Another cold
front will cross the lake by daybreak Tuesday with a return to
northwest to north flow. A ridge will follow Tuesday night with
the flow finally returning to a southerly direction Wednesday.
Ohio...beach hazards statement until 10 PM EDT this evening for
PA...beach hazards statement until 10 PM EDT this evening for
Marine...Small Craft Advisory until 10 PM EDT this evening for