Area Forecast Discussion
Issued by NWS Wilmington, OH-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KILN 212349
Area Forecast Discussion
National Weather Service Wilmington OH
649 PM EST Sat Jan 21 2017
Temperatures will remain mild through Wednesday before cooling
to more seasonable levels by the end of next week. A storm
system and surface low pressure center will ride up into the
lower Ohio Valley and Tennessee Valley region Sunday and then
move very slowly northeastward along the eastern slopes of the
Appalachians. This system will keep our weather unsettled
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Regional radar mosaic has shown some enhanced echos developing
across the eastern portions of the forecast area. Echos are
still light but there are some embedded showers that could be
producing some light rain at the surface in spots. The HRRR has
been representing this fairly well today and continues to show
some backbuilding of isold showers further west across the area
through the overnight period. Consequently increased pops
across the entire area tonight to handle this potential. Any
precipitation will be light. There will also be the potential
for some fog in our far northwest where there is a better chance
for some clearing overnight. Did beef up the fog a bit for
these areas, generally north and west of a Richmond to
Versailles to Kenton line.
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
Storm system poised to push into the Ohio Valley by Sunday will
produce some overrunning precipitation from south to north
through the day. Areas along the Ohio River should expect to
see rain developing by around sunrise or just after. Rain should
push northward from there, entering our northern most zones by
late afternoon. Forecast soundings did suggest a hint of some
elevated instability. As such continued to included a mention of
thunder. However, better instability appears to hold off until
later in the day as the storm center gets closer to our area and
generally across the southern third of our area.
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
A significant change in the overall mean flow will occur during the
coming week, with ridging building into the western United States
and troughing in the east. This will signal a return to more normal
winter like temperatures late in the week along with the chance for
periodic light snow showers and rain showers from Wednesday night
into Friday night.
However, before this transition occurs we will be focused on low
pressure at the surface and aloft that will be moving out of the TN
Valley northeastward up the Appalachians from Sunday night into
Monday. This will bring rain to the forecast area. There is fairly
good agreement among the models on this scenario and agreement that
the heaviest rains will remain south and east of the forecast area.
The 12Z NAM is an outlier with QPF in our area, generating in excess
of 1.5 inches in parts of the southern forecast area from late
Sunday into Monday night. However other models and GFS ensembles and
the SREF support lower rainfall totals during this time, and this is
reflected in WPC guidance and the NDFD forecast.
In the wake of the low pressure moving off to our northeast,
somewhat cooler air will move into the area at the start of the
week. However temperatures will remain above normal, and
temperatures will warm even more on Wednesday ahead of an advancing
cold front. Brief ridging at the surface and aloft will build into
the OH Valley and Great Lakes Tuesday, ahead of the advancing cold
front. The cold front will move east of the area late Wednesday, and
this will signal a downward trend in temperatures that will continue
through the end of the week.
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --VFR conditions will prevail through much of the period. Mid deck
will persist overnight. There could be a few light showers
falling out of those clouds, with central Ohio having the better
chance of seeing any precipitation. But even if that occurs, there
will be no restrictions. South winds will back to easterly towards
Clouds will lower during the day as showers spread north ahead of
a surface low. Conditions will stay VFR initially as precipitation
starts, but some heavier pockets of rain will eventually cause
some MVFR visibilities. In addition, moistening low levels will
lead to MVFR ceilings developing below 2000 ft before the TAF
period ends. Winds will back further to northeast and strengthen
OUTLOOK...MVFR/IFR ceilings and visibilities will occur Sunday
night into Monday night. MVFR ceilings may linger into Tuesday.
MVFR ceilings possible again Wednesday into Thursday.
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