Area Forecast Discussion
Issued by NWS Wilmington, OH
FXUS61 KILN 311945
Area Forecast Discussion
National Weather Service Wilmington OH
345 PM EDT WED AUG 31 2016
A cold front will move south of the Ohio River by Thursday morning.
High pressure and a dry airmass will then build in through the
weekend. Cooler than normal temperatures accompanying the high
will gradually warm to near normal by Sunday as the high shifts
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Showers and thunderstorms, most numerous across central Ohio, will
continue east/southeast through the rest of the afternoon and
and early evening. This main convection is associated with a
prefrontal convergent trof axis, with the main cold front trailing
behind to the north.
For later this evening and overnight, the cold front will move
south toward the Ohio River. The loss of diurnal instability and
weak frontal convergence will cause the chance of showers and
thunderstorms to gradually diminish. Have taken a blend of MOS/raw
2 meter temperatures for lows. Lows will range from the upper 50s
northwest to the upper 60s far south.
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
The cold front will move south away from the area on Thursday.
Drier and cooler weather will filter into the region from the
north. Skies will become mostly sunny all locations by early
afternoon, but some diurnal CAA cumulus clouds may offer a little
more cloud coverage in the northwest by mid/late afternoon. Highs
will range from the mid 70s north to near 80 along and south of
the Ohio River.
Dry weather is expected for the period Thursday night through
Friday night as sprawling surface high pressure sets up residence
across the Great Lakes. Temperatures will be a little bit below
normal for the period...with lows in the 50s and highs 75 to 80.
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Until the track of the tropical system (now designated as Hermine)
becomes better known, there will be a little bit of uncertainty
regarding the forecast for the Ohio Valley over the weekend. As 12Z
models have shifted slightly west, expected impacts have moved a
little closer to Ohio and Kentucky. For now, however, there is no
reason to alter the dry and warming forecast -- with high confidence
in a pronounced mid-level ridge building in over the Mississippi
Valley and Great Lakes. As this ridge continues to sharpen, with
height rises over the ILN forecast area expected to continue well
into next week, dry conditions and warming temperatures will be
required in the forecast. This overall shift in pattern appears very
likely, with strong agreement from individual members in the 12Z
GEFS. However, details in the eventual strength of the ridge
(especially at its center in the southeastern states) appear to be
tied to the tropical concerns, with greater spreads in the exact
placement of the features by Monday and beyond.
The max temp forecasts have already been somewhat generous with
temperatures, and this trend will be continued, with slight
increases in the forecast for Monday through Wednesday. This will
bring temperatures to values near 90 in the southern / southeastern
sections of the forecast area, and lower 90s possibly on Wednesday.
With increasing moisture (dewpoints moving into the upper 60s to
near 70) the chance for precipitation will increase slightly by
Tuesday and Wednesday. With little in the way of organized forcing
expected, this will be kept in the 20-30 percent range and generally
diurnal in nature.
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
Convection is now developing from KDAY-MKFD line, which appears to
be in the vicinity of the front. Dropped the tempo group from
KDAY taf and went with a VCTS based on the current radar loop. For
the rest of the tafs, went with a 3 to 4 hours of tempo mvfr vsby
in TSRA until the convection works thru the region.
By 00Z expect the convection to be south of the tafs, with a mid
deck remaining over the tafs. As drier air begins to filter into
the region on north winds tonight, the AC should scatter out.
However there are indications on the forecast time sections that
some IFR stratus could form. Right now only put in scattered
stratus, but will have to keep an eye on it and see if broken cigs
develop. Dissipated any stratus by 13Z, leaving VFR conditions.
OUTLOOK...No significant weather expected.