Scientific Forecaster Discussion
fxus61 Kiln 281757
Area forecast discussion
National Weather Service Wilmington Ohio
157 PM EDT Fri Jul 28 2017
an area of low pressure will move across northern Kentucky and
into West Virginia today, providing continued showers and
thunderstorms. High pressure will build in behind the departing
low for the weekend.
Near term /until 6 PM this evening/...
a frontal boundary has slipped south overnight and stalled out
E-W near the Ohio River. This front has been the focus for new
convective development. Wave of low pressure will ripple along
this quasi-stationary boundary today. The environment is very
moist with precipitable water values above 2 inches. This moist
airmass along with favorable flow for some back building, deep
warm cloud depth and saturated soils will lead to flooding.
Therefore, have bumped pops into categorical range and issued a
Flash Flood Watch for iln/S southern counties thru the
Clouds will continue with only some late day breaks possible
across the northwest County Warning Area. These clouds and precipitation will
hold temperatures below normal today, with highs only rising
into the upper 70s/around 80.
Short term /6 PM this evening through 6 PM Saturday/...
any evening showers, mainly across the eastern cwa, will come
to an end as low pressure moves further away from the area
tonight. North/northwest flow will bring in drier air, and
support clearing skies from west to east tonight. This will pave
the way for a good deal of sunshine on Saturday, with lower
humidity and temperatures 5 to 10 degrees below average.
Long term /Saturday night through Thursday/...
pattern of a ridge over the west/trough in the east looks to
continue for much of the long term, placing the Ohio Valley in a
northwest flow. At the surface, high pressure builds from the
Great Lakes Sunday into Monday before shifting east for the
middle of the week.
Dry conditions are expected to continue through Wednesday as
temperatures moderate back into the mid 80s for highs/mid 60s
for lows. A cold front will approach toward the end of the
week, but timing is still uncertain. With moisture/instability
increase, have a chance of thunderstorms on Thursday and if the
front is still in the vicinity then the chance of thunderstorms
may continue into Friday.
Aviation /18z Friday through Wednesday/...
frontal boundary is slowly sagging south of the Ohio River
taking the widespread showers and thunderstorms with it. Upper
low over se lower Michigan dropping southeast thru NE Ohio to
a position over western PA by morning. This feature will keep a
chance of a shower or perhaps a thunderstorm in the forecast
mainly over kcmh/klck thru the afternoon.
Moisture will decrease and clouds will rise with lingering MVFR
ceilings becoming VFR this afternoon. Expect VFR conditions
overnight and into Saturday as surface high pressure builds
into the Great Lakes.
North winds will gust up to around 20 kts this afternoon into
this evening and then north-northeast winds will gust up to 22
kts Saturday afternoon.
Outlook...no sig weather expected.
Ohio...Flash Flood Watch until 5 PM EDT this afternoon for ohz081-088.
Kentucky...Flash Flood Watch until 5 PM EDT this afternoon for kyz098>100.