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Area forecast discussion
National Weather Service Cleveland Ohio
322 am EDT Fri Mar 24 2017

a warm front over the Midwest will lift north across the area
this morning. Saturday, low pressure over Missouri will move
northeast to near Chicago by Sunday morning. Sunday the low will
continue northeast across the central Great Lakes.


Near term /through today/...
rain moving east across the area early today. If timing holds,
the precip should move east of Ashtabula/Trumbull counties
around 7am and out of northwestern PA around 8am. Have moved pops to
categorical in the grids across the region through the early
morning based on timing. Will also linger likely/chance pops in
northwestern PA into mid morning in case timing is too fast. With the
warm front north of the area for the late morning and
afternoon...still believe there will be at least some sunshine.
Will still hold onto 65 to 70% coverage but should yield a
"partly sunny" forecast in the zones. Impressive warm advection
took place from late yday and through the night. By 12z 850mb
temps should be +10 to +12c across the area. This along with the
broken sunshine should get afternoon temps into the 60s. Early
today models show a 50-60kt low level jet across the area. Winds
drop off back to around 30kts later this afternoon. With good
mixing expected it should be a breezy day with sustained winds
15 to 25 mph with gusts over 30mph.


Short term /tonight through Monday night/...
tonight the warm front will be to our north but should begin to
sag south towards morning possibly nudging back into the area.
Believe for the most part we should remain dry with the focus
for precip remaining north of the front. Will bring a slight
chance into the northern counties after midnight and then
increase to low chance pops extreme north towards dawn. Saturday
glfmx moisture will begin to get pulled north through the
Mississippi Valley ahead of the low in Missouri. Looking at the
NAM and GFS this deeper moisture doesnt quite reach into the
area however it will be just to our west and south by 00z
Sunday. Still, enough moisture in the deep southerly flow to
expect scattered showers. The NAM also brings 500 j/kg of cape
into the western counties during the afternoon. Best chances
will be west so will have likely pops there and chance pops
elsewhere. Will also have a chance of thunder where pops are
likely. No big changes for the rest of the period. Saturday
night and Sunday look wet as the Gulf moisture gets wrapped
across the area. Sunday night the low weakens and the moisture
begins moving northeast out of the area. Forcing is minimal so
will continue lowering pops through the night west to east.
Monday will still keep chance pops in place as low pressure
moves across southern Missouri. Temps on the mild side.


Long term /Tuesday through Thursday/...
extended pattern continues to be in a state of flux with fairly
rapid transitions between shortwave troughs and minor ridging taking
place. This means overall weather pattern will be fluctuating
between dry periods and wet periods. Polar jet stream is progged to
remain north of the area keeping any Arctic air masses from pushing
south into the forecast area for the foreseeable future.

First in a series of upper level trough/ridge pairs moves east into
the area Tuesday. This trough will develop a weak positive vorticity
maximum and result in a weak surface low pressure system that will
move east across the Ohio Valley region. Limited moisture with the
features will move east across the forecast area as well on Tuesday.
Hence, will keep a mention of showers in the forecast during the day
pulling out to the east Tuesday night as the upper level and surface
ridge builds east.

Upper level ridge amplifies Wednesday and Thursday helping to build
surface ridge over the area. Then, by Thursday, next trough diving
southeast out of the northern rockies evolves into a potent upper
level low pressure system that becomes vertically stacked over
Arkansas. Once the low pressure system rounds the base of the mean
trough, it lifts northeast toward the area to bring more rain to the
area by Friday.

As mentioned, temperatures should remain mild through the forecast


Aviation /06z Friday through Tuesday/...
a warm front will begin to lift north across the area this
morning while an upper level feature slides east along the warm
frontal boundary. Showers will move east with the upper level
feature early this morning and then end by day break. Ceilings
should remain VFR through the duration of the rainfall. Main
issue will be the development of wind shear between 1500 and
2000 feet and winds increase to 45 to 50 knots along the warm
front. Once warm front lifts north, stronger winds will mix down
to the surface ending threat for wind shear this morning. As
upper level feature moves east and warm front lifts north, we
should see improving ceilings to 25000 feet. Then, another shot
of low level moisture will push east over the area tonight
dropping ceilings down to around 2500 feet. Winds will diminish

Outlook...areas of non-VFR Saturday and Sunday. Non VFR
possible again Monday night and Tuesday.


Lake winds will be on the increase today as a warm front lifts north
of the area. Warm air advection in the wake of the warm front will
likely be strong enough to push the cold dome over the lake to the
north allowing some of the wind to mix down to the surface. Not
expecting Small Craft Advisory criteria to be met due to short fetch
over the nearshore waters. Winds diminish overnight as warm front
becomes stationary and tries to push back south as a back door cold
front late tonight. Northeast flow develops Saturday and will likely
need a Small Craft Advisory headline by Saturday morning continuing
into Sunday morning. Warm front lifts back north Sunday allowing
winds to diminish once again. Generally light and variable winds
Monday into Tuesday.


Cle watches/warnings/advisories...



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