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Area forecast discussion 
National Weather Service Paducah Kentucky
648 am CDT Wednesday Jul 27 2016

Update...
issued at 648 am CDT Wed Jul 27 2016

The aviation section has been updated for the 12z taf issuance.

&&

Short term...(today through Friday night)
issued at 309 am CDT Wed Jul 27 2016

A few showers are moving northeast over the southeast corner of
the forecast area at this time. The latest hrrrs indicate that
this will continue through sunrise and then it should dissipate
quickly later this morning. The most recent hrrr runs have backed
off on development along the northwest periphery of the area this
morning. Will keep some chance pops up there through the morning,
but have already backed off from original plan up there.

All indications from the 00z guidance are that a weak surface
boundary will set up somewhere near the Ohio River by this
afternoon. This boundary will likely be a focus for thunderstorm
development through the afternoon. Focused good chance pops there,
but may ultimately need higher pops. Locally heavy rainfall and
lightning will be the primary concerns with convection today.

For tonight into Thursday, the primary mid/upper-level trough
will move eastward through the region. This should lead to an
increase in coverage of showers and storms by late tonight,
especially over the southeast half of the region. The 00z European model (ecmwf) is
the best match for this portion of the forecast. Heavy rainfall
will be more widespread in this time frame, and could lead to some
flooding issues, especially in areas that receive heavy rain this
afternoon and again tonight and Thursday. Do not think a Flash
Flood Watch is necessary at this time, but if the heavy rainfall
is more widespread than anticipated this afternoon one may become
necessary. For now will just talk it up in the severe weather potential statement.

Thursday night through Friday night is much drier, but we still
have good chance pops over much of the region. With a substantial
short-wave trough aloft moving through Thursday, would expect
subsidence to severely limit any precipitation for much of
Thursday night.

For Friday and Friday night we will still be under cyclonic flow
aloft and there could be some remnant of the old surface boundary
in our vicinity, so a disturbance or two could touch off some more
convection in either period. However, the general trend in guidance
is to push development southward, possibly keeping the entire area
dry. Suspect that we have too much pop for these periods.

High temperatures will be highly dependent on convective trends
through Friday. We may be a bit too warm Thursday, but otherwise,
tried to lean toward the warm side of the guidance envelope. Lows
will continue to run above normal.

Long term...(saturday through tuesday)
issued at 309 am CDT Wed Jul 27 2016

Medium confidence in the extended.

The latest model runs continue to show a nearly stationary upper
level trough over the area at the start of the extended. This will
provide for upward forcing with a surface reflection of a cold front
that will also be near stationary or meandering over the region. The
front starts to lift north and finally eastward early next week as
high pressure starts to build in from the west. Even though the high
is building in we will be in the warm sector allowing for at least
afternoon chances of storms but not likely overnight next week.
Finally another stronger front will be poised over the Central
Plains and should move in by mid week bringing our next chance of
strong storms to the region. Temperatures will be below normal most
of the extended then warm to near normal as the high and cold front
approach the region. However dew points stay around 70 which will
keep muggy conditions well established across the region day and
night. Most of the storms will remain below severe criteria but with
abundant moisture and afternoon heating any storm will be capable of
producing strong to severe winds and small hail as well. One
limiting factor for storms especially Saturday will be a subsidence
inversion.

&&

Aviation...
issued at 648 am CDT Wed Jul 27 2016

MVFR fog at kcgi and kpah and lower conditions in fog at kowb will
burn off in the first hour or two of the forecast. A lower MVFR
ceiling may develop as the fog lifts. Convection is expected to be
scattered this afternoon mainly in the southern half of the area.
Maintained the thunderstorms in the vicinity treatment, but left kevv dry, as coverage will
be lacking in that area. We may see scattered showers and
thunderstorms through the evening, but more widespread showers
and thunderstorms expected overnight, mainly east of the MS river.
Winds will be light through the forecast, so in the absence of
convection and associated cloud cover, fog will be a possibility
again late tonight.

&&

Pah watches/warnings/advisories...
Illinois...none.
MO...none.
In...none.
Kentucky...none.
&&

$$

Update...drs
short term...drs
long term...kh
aviation...drs

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