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fxus61 Kiln 271523 
afdiln

Area forecast discussion
National Weather Service Wilmington Ohio
1023 am EST Mon Feb 27 2017

Synopsis...
a weak upper level disturbance will result in a chance of
showers today. A warm front will lift north across the region on
Tuesday, leading to mild temperatures and a chance for showers
and thunderstorms. A cold front will sag slowly southeast
across the region Tuesday night into Wednesday. This will bring
a continuation of widespread showers and thunderstorms through
mid week.

&&

Near term /until 6 PM this evening/...
an upper level disturbance will continue to move across the
region today. In addition isentropic lift will be present across
primarily eastern portions of the forecast area. Due to this
have higher rain chances across eastern portions of the region
today. The upper level disturbance and isentropic lift will push
out of the area by this evening and precipitation is expected
to briefly taper off.

Decreased temperatures today with cloud cover and precipitation.
Guidance values support this as well.

&&

Short term /6 PM this evening through Wednesday/...
a warm front will approach from the southwest overnight and then
lift northeast across our area through Tuesday morning. This
will be accompanied by strengthening southwesterly low and mid
level flow on Tuesday with a 40-50 knot 850 jet nosing into
western portions of our fa toward daybreak and then
overspreading the rest of our area during the mid to late
morning hours. In increasing low level convergence and
isentropic lift, expect to see shower development spread into
southwest/western portions of our area late tonight and then
become more numerous across the remainder of our area as we
progress through the morning on Tuesday. As we get more into
the warm sector and start to see some destabilization, some
embedded thunder will also be possible. This activity should
then push off to our east through the afternoon hours on
Tuesday. In developing low level warm air advection, expect highs on Tuesday
mainly in the 60s.

Short wave energy will move out of central rockies and into the
Great Lakes region Tuesday night into Wednesday. As it does, a
cold front stretching from the Great Lakes into the mid
Mississippi Valley will sag slowly southeast into our area
Tuesday night into Wednesday, with waves of low pressure riding
northeast along the front. There continues to be some model
timing and placement issues with the front as it moves through
our area on Wednesday, with the 00z GFS and CMC generally
faster than the 00z European model (ecmwf) and NAM. Nonetheless, in broad and
strong southwesterly flow ahead of this, strong moisture
transport will develop across the region Tuesday night with pws
pushing up into the 1.25 to possibly 1.5 inch range. This will
also help pull some better instabilities northeast into at least
western portions of our fa later Tuesday night into Wednesday
morning. This will allow for more widespread showers and
thunderstorms to develop/spread into our area Tuesday night and
push down across our area heading into Wednesday. Very strong
wind fields will result in impressive lower and deep shear
values and hodographs. The biggest question will be the amount
of instability but it does looks like there should be at least
enough to combine with the strong dynamics to result in a decent
severe threat Tuesday night into Wednesday. Given the high pws
and possibility for some training storms, heavy rain will also
be a concern. Gefs plumes are ranging from 1 to 2 inches of rain
across our area and we could end up with localized higher
amounts than this. Six hour ffg values are running around 2
inches so we may very well end up with some flooding concerns as
well Tuesday night into Wednesday.

Temperatures will likely be non diurnal both Tuesday night and
Wednesday and will be dependent on the exact timing of the
front. Will keep temperatures pretty steady Tuesday night given
the good southerly flow and then start to drop them off across
at least the northwest heading into Wednesday afternoon.

&&

Long term /Wednesday night through Sunday/...
a weak clipper type system will drop down out of Canada
Wednesday night and pivot east across the Great Lakes Thursday
into Thursday night. This will lead to a chance of showers for
Thursday afternoon into Thursday night, with the highest pops
across our northeast, closest to the better forcing. Depending
on the timing, we may be cold enough for a brief mix across our
northwest on Thursday. However, thermal fields off the forecast
soundings suggest the pcpn should be mainly liquid during the
day on Thursday, before possibly changing over to some snow from
the north Thursday night before ending.

Weak mid and upper level ridging will develop through the end of
the week. A weak short wave may drop down across the Great Lakes
on Saturday but it looks like any pcpn associated with this
should remain well off to our north. In developing warm air advection,
temperatures will moderate through the weekend with readings
pushing well above normal once again.

&&

Aviation /15z Monday through Friday/...
light precipitation will continue to spread up into areas
mainly to the southeast of I-71 this morning. This is in
association with a weak upper level disturbance that will push
east across the area through this afternoon coupled with a
30-40 knot low level jet that is nosing up into the Ohio Valley
this morning. Cigs are running VFR attm but they should lower
down into MVFR later this morning as the lower levels continue
to saturate. The better forcing will mostly shift off to the
east through this afternoon, but with some weak isentropic lift
persisting, a few showers may linger through the afternoon
hours. Will generally cover this threat with a vcsh. Cigs should
lift back into VFR heading into this evening. A warm front will
approach from the southwest late tonight and into Tuesday
morning. This will lead to some shower development toward
daybreak with a chance of showers and possibly a thunderstorm
then continuing through the morning hours.

Outlook...MVFR ceilings will be possible into Wednesday along
with a chance of thunderstorms. MVFR ceilings may linger into
Wednesday night and be possible again Thursday night. Wind gusts
to 30 kts will be possible Wednesday afternoon and evening.

&&

Iln watches/warnings/advisories...
Ohio...none.
Kentucky...none.
In...none.

&&

$$
Synopsis...jgl

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