Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 07/16/22

Area Forecast Discussion

National Weather Service Louisville KY

 735 PM EDT Fri Jul 15 2022

...Updated Aviation Discussion...

.Short Term...(This evening through Saturday)
Issued at 247 PM EDT Fri Jul 15 2022

Current surface analysis reveals a very weak, diffuse surface
boundary/moisture gradient across portions of southern Indiana and
central Kentucky. Afternoon cu field has developed in most areas of
ample surface heating, though warmer air above ~850mb (via AMDAR
soundings) has kept a `cap` on any convective/shower development.
The cap will gradually weaken through the afternoon, and we could
see some very, very isolated showers develop, but expect most areas
to remain dry in the near term.

Regional radars show a broad area of showers with a very occasional
rumble of thunder stretching from central Missouri into northern
Indiana, slowly drifting toward the southeast. Cloud cover ahead of
this area of precipitation has already started to drift into northern
portions of the CWA, and coverage should increase through the
remainder of the day. This area of precipitation is associated with
a weak shortwave which will gradually weaken as it pushes southeast.
Models depict coverage of this precipitation to become isolated to
widely scattered by the time it arrives in our neck of the woods
this evening, and mainly impact portions of southern Indiana and
northern Kentucky through the overnight hours.

Some lingering isolated to widely scattered showers will likely be
ongoing Saturday morning, but activity is expected to gradually
diminish in coverage and push east of I-65 Saturday afternoon. Most
areas should remain dry Saturday, and temperatures will be on the
warm side, with highs climbing into the low and mid 90s in many
spots.

.Long Term...(Saturday night through Friday)
Issued at 305 PM EDT Fri Jul 15 2022

Sunday and Monday...

As we move into the second half of the upcoming weekend, wetter and
milder conditions are expected across the Ohio and Tennessee
valleys. Sunday morning, a mid-level shortwave will move from NW to
SE from the upper Mississippi Valley into the lower Great Lakes
region. This feature is expected to bring quite a bit of moisture
along with it, with NAEFS and EPS ensemble mean PW values expected
to approach or slightly exceed 2 inches by Sunday afternoon.
Additionally, model soundings depict "tall, skinny" CAPE profiles,
which will both limit severe potential and promote efficient
rainfall within heavier precipitation cores. With around 500 J/kg
MLCAPE to work with, thunder will be possible, especially across
southern KY, but mediocre shear should help keep heavy rainfall as
the main threat for convection Sunday into Monday.

Temperatures for Sunday into Monday will be kept in check by
increased cloud cover and precipitation, with highs both days
generally in the low-to-mid 80s, although some parts of southern IN
will struggle to reach 80 degrees Sunday afternoon. Lows will be
mild both Sunday and Monday morning, with minimums ranging from the
upper 60s to the mid 70s. In total, by the time the bulk of the
precipitation exits the region Monday night, most if not all
locations across the region should see some rainfall, with anywhere
between 1 and 2 inches of QPF expected on average, and higher totals
possible where heavy showers/storms persist for an extended time.

Tuesday through Friday morning...

For Tuesday and Wednesday, expect temperatures to warm back above
normal levels as the mid-level trough departs to the NE and ridging
centered over the Four Corners region creeps into the area from the
west. By Wednesday afternoon, another shortwave will try to swing
along the periphery of the large scale ridge, bringing another
chance for rain as it swings through. 15/00Z WPC Ensemble Cluster
Analysis reveals that there is a bit of a discrepancy between the
GEFS and EPS families, with more GEFS members developing a higher-
amplitude wave while the EPS members tend to depict a weaker
shortwave. Additionally, the 15/12Z deterministic GFS run brings in
greater low-level moisture ahead of the mid-level disturbance, which
would contribute to greater shower and thunderstorm chances
Wednesday afternoon and evening, while its ECMWF counterpart keeps
things drier. Regardless, it appears that this system will be much
drier overall than the one for Sunday/Monday, with south central and
eastern KY expected to have the best shot at seeing any
precipitation during the mid-week time frame.

After the surface "cold" front associated with the aforementioned
mid-level disturbance passes through Wednesday night/Thursday
morning, low/mid-level NW flow will dry things out for the end of
the upcoming week. The incoming air mass behind the mid-week front
is not expected to bring much cooler air, with highs behind the
front still expected to reach the upper 80s and lower 90s. Beyond
the extended forecast period, current guidance suggests persistent
ridging may set up across most of the CONUS, with a return of well-
above normal temperatures favored for the end of July.

&&

.Aviation...(00Z TAF Issuance)
Issued at 735 PM EDT Fri Jul 15 2022

Satellite imagery over the Ohio Valley shows high clouds working
over the area as a weak system moves through IL and IN. Radars
across IN/IL have been showing areas of showers and a few embedded
thunderstorms but this activity continues to weaken as it works into
southern IN and central KY. While a passing shower/sprinkle is
possible this evening for HNB/SDF/LEX the threat looks very low as
we continue to have mostly dry air in the lower layers. The low end
chance of precipitation carries over into tomorrow morning but given
how low the chances are continue to keep them out of the TAF. Winds
will be light trough the overnight.

Tomorrow, clouds will break some and winds will increase a bit out
of the south. Flight categories through tonight and into tomorrow
look to remain VFR.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
IN...None.
KY...None.
&&

$$

Short Term...DM
Long Term...CSG
Aviation...BTN