Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
736 PM EDT Tuesday Jun 2 2015
a ridge of surface high pressure over the Northern Ohio valley
will undercut a strong upper low in the eastern Tennessee Valley.
An inverted trough of surface low pressure will nose into the
region near or along the I-71 corridor. Southeast of the trough
will see increased humidity and a slightly increased chance of
Near term /until 6 am Wednesday morning/...
significant cloud cover will persist through much of the night
and see some erosion on the northern edge in Northern Ohio and
western edge running north-S through Indiana. Low temperatures will be
similar to previous nights in the lower 50s...could go lower into
the middle and upper 40s if cloud cover clears out
significantly...particularly north of I-70 corridor. Record lows
are in the lower 40s at this time of year so there is not much of
a threat of getting that cold.
Short term /6 am Wednesday morning through Thursday night/...
significant cloud cover will still be present over the region
Thursday and through the forecast period. The region will see some
dry air mixing in late...but a pessimistic cloud forecast seems to
be the better side to err on given the upper low only starting to
make an eastward progression to the Carolina coast Thursday and
The inverted trough running along or at least near the I-71
corridor will have most of the available lower level moisture
pooled on the southeast side of it nearest the Ohio/WV line. If
sun does make an appearance in the next few days...there will be
an increased chance of shower activity in the late day and early
evening. This activity if present will decrease dramatically with
the loss of daytime heating. Vorticity maxima will rotate around
the upper low as well and enhance any upward motion found during
the late day. Did not continue thunderstorm chances as models
were very muted in quantitative precipitation forecast bulls eyes over the Ohio Valley and that
this appears to be a cold pool shower event with not enough
vertical motions available for charge separation.
Temperatures will continue to exhibit a warming trend...with highs
reaching the middle 70s Wednesday and the low 80s Thursday. Overnight
lows will warm to around 60 Wednesday night to the lower 60s Thursday night.
Long term /Friday through Tuesday/...
have used a blend of the 00z/12z European model (ecmwf) and wpc for the extended
For Friday into Saturday...there remains some issues on how strong a
middle level trough will be over southeast Canada/New England and how fast it
will push a cold front through the region from the north. Given that
the dynamics are on the weak side...will maintain chance probability of precipitation with
There are some indications that surface high pressure will try to
build in from the north/northeast Saturday night. We should be in a
lull in terms of the threat for precipitation with drier air over the region.
Another middle level trough and stronger cold front are forecast to dig
southeast and push east/southeast through the Great Lakes and the
Ohio Valley Sunday into Monday. With better dynamics and frontal
convergence...will raise probability of precipitation to high chance.
For Monday night into Tuesday...under northwest flow...some embedded
disturbances may work their way into the region. Low chance probability of precipitation
have been included with this possibility.
Temperatures will be near or slightly above normal through the
Aviation /00z Wednesday through Sunday/...
fairly widespread MVFR ceilings across the region have finally started
to break up over the last hour or two with kcmh and Kiln both
scattering out within the last hour. A quick look at the raw 00z
iln sounding is still showing a nice inversion around 3500 feet so
am concerned that much of this moisture will remain trapped below
the inversion overnight. Model guidance is somewhat mixed as to
whether or not this will occur. If for some reason the lower ceilings
continue to dissipate and do not redevelop...would think we would
have a decent shot at then seeing at least some MVFR br development
in the light flow regime. So from a categorical viewpoint...think
it is best to remain on the pessimistic side and stick with
persistence and either hang on to MVFR ceilings or allow for them to
redevelop in areas that have scattered out. However...confidence
is not terribly high with this forecast. Assuming the lower ceilings
are present Wednesday morning...they should slowly lift into VFR
through late morning/early afternoon.
Outlook...no significant weather expected.