Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Cleveland Ohio
921 PM EDT Tuesday Sep 2 2014
high pressure will build northeast up the Appalachian Mountains
through Wednesday night and off the East Coast by Thursday night. A
warm front will lift northeast across the area Thursday followed by
a cold front Friday evening. High pressure will build southeast
across the region into the weekend.
Near term /until 6 am Wednesday morning/...
convection with diffuse cold front now reduced to 3 small clusters.
Very little lightning occurring. RUC hangs on to a few cells throughout
the night so will slow pop drop off enough to keep slight chance
going longer into the night.
Much of the cloud cover from earlier in the day has dissipated
leaving patchy lower clouds with band of jet induced cirrus above.
Weak cold advection looks even more likely to not be strong enough
to bring in the drier air as quick as thought earlier so will inch
lows up even another degree over the southeast 2/3 of the area.
Short term /6 am Wednesday morning through Friday night/...
broad upper level trough will move east of the area overnight
setting up a zonal flow across the country once again. Surface high
will build northeast and then east of the area by Wednesday night.
Warm air advection will resume on Thursday with a pretty good surge
of warm air racing northeast into the forecast area. 850 mb
temperatures rise from 16c Wednesday night to 20c by Friday.
Increased dew point air will return and bring with it higher
humidity on Friday.
Cold front is expected to move east across the region Friday
evening. Convection is expected to remain associated with the cold
front Friday afternoon into Friday night. Otherwise...no major
threat for showers and thunderstorms through the extended period
until Friday afternoon. Will have to keep an eye on the cold front
Friday for severe potential due to ideal timing in the heat of the
Long term /Saturday through Tuesday/...
a surface cold front will be just about out of the area at daybreak
Saturday. There could be a few showers along and behind the front
but rapid drying will occur during the afternoon. Readings next
weekend will be back below normal with lows Monday morning possibly
getting into the 40s. Sunday will be a pleasant day with abundant
sunshine. The Fall like weather will continue on Monday. The
surface high responsible for the quiet weather will eventually move
off to the east on Tuesday allowing warmer southerly flow to
return. Expect temperatures Tuesday to average near normal. Precipitation
chances should hold off till just after the period ends.
Aviation /00z Wednesday through Sunday/...
the cold front will sag across the area this evening with a few
more showers that may produce brief MVFR conditions. The drier air
will be slow to filter in and the wind will become light and fog
is likely in many areas by daybreak. Stratus is also possible...
mainly at inland sites and IFR conditions may occur for several
hours into middle morning. The fog and stratus should
dissipate...perhaps evolving into a cumulus field (sct-bkn035-045)
for a while. VFR conditions should prevail by late morning
everywhere. Lake breeze wind shifts likely at kcle and Keri.
Outlook...non VFR likely in showers and thunderstorms by Friday
evening into Saturday with the next cold front.
a surface cold front will move east of the lake by early this
evening. Lingering showers over the lake will also be gone by that
time. Expect the flow to become westerly behind the front and then
light and variable overnight. Light flow will then continue
Wednesday with southerly flow developing on Thursday as a surface
ridge pushes east of the lake. South to southwest flow will then
gradually increase ahead of a cold front that will drop south across
the lake early Saturday. More precipitation is likely with this front with
the flow becoming north behind it. Do not think speeds will be
strong enough for small craft headlines. Northerly flow will
continue through Sunday. Speeds most if not the entire period will
be under 15 knots.