Special Weather Statement, NWS Louisville, KY

Area Forecast Discussion
National Weather Service Louisville KY
320 PM EDT Thu Oct 7 2021

.Short Term...(This evening through Friday)
Issued at 315 PM EDT Thu Oct 7 2021

A low pressure system is currently just north of St. Louis, MO. From
now until sunset tomorrow, this closed upper low will get pushed to
the northeast until it's over Lake Michigan. This is keeping
boundary layer winds from the south throughout the CWA, and will
keep scattered showers and thunderstorms moving northward in an
environment with MLCAPE between 1,000 to 1,500 J/kg, PWATs around
1.5", and very little directional shear. With normalized CAPE values
of 0.1 or less, CAPE profiles are long and skinny, so severe weather
isn't expected. CAM guidance has most of this evenings activity east
of Interstate 65.

The main focus tonight is east of a line running through Louisville
and Bowling Green. Guidance is varied on a low stratus/fog event.
Believe with all the low level moisture it will likely be more low
stratus with areas of fog, but this is also dependent on where there
is extra moisture from rainfall today and areas of clear skies
tonight. Widespread 500 foot and lower ceilings are likely with near
calm winds. Low temperatures are expected to drop to near 60 with
Louisville remaining in the mid 60s.

Tomorrow, ahead of a shortwave that will clear the area of moisture,
a few isolated showers and storms will likely move through southern
Indiana and central Kentucky. Any shower will likely only drop a few
hundredths or so of rain. High temperatures are expected in the mid
70s to 80.

&&

.Long Term...(Friday night through Thursday)
Issued at 255 PM EDT Thu Oct 7 2021

Overview...Expect a foggy start to an otherwise warm, dry, and sunny
weekend as high pressure builds into the region. A succession of
systems will see the return of rain chances Monday into Tuesday
morning and again Thursday.

The Weekend...The upper low now over the lower Great Lakes will open
up into a trough with its axis lying SSE across central KY as 5H
ridging builds in over the area and surface high pressure spreads
across much of the Eastern US. Look for fog to development overnight
into Saturday morning as a result of abundant low level moisture,
light winds, and clearing skies. Fog will dissipate by late morning
leading to mostly sunny skies by mid afternoon. Southerly flow on
the western side of the surface high will continue to advect warm,
moist air into the region resulting in afternoon highs in the low to
mid 80s and dew points in the mid 60s for the weekend.

Monday into Tuesday Morning...By Monday the upper ridge axis moves
to the east of central KY as a mid-level disturbance experiences lee-
side cyclogenesis with a closed low forming over the TX Panhandle.
Models tend to agree with the strength of the upper ridge over the
Gulf and Eastern US deflecting most of this upstream energy to the
NE on a trajectory toward the Great Lakes. Models also time the
approach of the cold front during the diurnal minimum from Monday
night into Tuesday morning along with abundant mid-level dry air. So
will go with slight to chance PoPs for this period.

Tuesday Afternoon and beyond...Brief upper ridging moves into the
region as a stout mid-level impulse with Pacific origins digs deep
into the longwave trough over the Southwest CONUS. Fair weather is
expected Tuesday afternoon through much of Wednesday over the OH
Valley before this disturbance brings the return of rain chances for
Wednesday night into Thursday. Temperatures remain in the upper 70s
to low 80s through mid week.

&&

.Aviation...(18Z TAF Issuance)
Issued at 202 PM EDT Thu Oct 7 2021

Today, expect improving ceiling at HNB over the next couple of hours.
SDF and HNB are going to border areas of expected rainfall, but
believe they will remain mostly dry and under VFR conditions through
the rest of the period. LEX stands the best chance at seeing a
passing shower/thunderstorm this afternoon/evening.

Tonight, LEX is of greatest concern as fog is expected over much of
the Bluegrass and Lake Cumberland regions, but with a layer of
stratus, this could be a low stratus/fog event. This is also
dependent on which areas see rain today and/or clear skies tonight.
Ceilings could drop into IFR conditions with the possibility of fog
crashing visibilities. BWG will likely see fog as well but to a
lesser extent.

&&

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

Short Term...KDW
Long Term...CG
Aviation...KDW

Hazardous Weather Outlook
National Weather Service Louisville KY
326 PM EDT Thu Oct 7 2021

INZ076>079-083-084-089>092-KYZ023>043-045>049-053>057-061>067-
070>078-081-082-081930-
Orange-Washington-Scott-Jefferson-Dubois-Crawford-Perry-Harrison-
Floyd-Clark-Hancock-Breckinridge-Meade-Ohio-Grayson-Hardin-Bullitt-
Oldham-Trimble-Henry-Shelby-Franklin-Spencer-Anderson-Woodford-
Fayette-Bourbon-Nicholas-Nelson-Mercer-Jessamine-Larue-Marion-Boyle-
Garrard-Madison-Butler-Edmonson-Hart-Green-Taylor-Casey-Lincoln-
Logan-Warren-Simpson-Allen-Barren-Monroe-Metcalfe-Adair-Russell-
Cumberland-Clinton-
Including the cities of Paoli, Salem, Scottsburg, Madison, Jasper,
English, Tell City, Corydon, New Albany, Jeffersonville, Lewisport,
Hawesville, Hardinsburg, Brandenburg, Hartford, Leitchfield,
Elizabethtown, Shepherdsville, Louisville, La Grange, Bedford,
Milton, New Castle, Shelbyville, Frankfort, Georgetown, Cynthiana,
Taylorsville, Lawrenceburg, Versailles, Lexington, Paris, Carlisle,
Bardstown, Springfield, Harrodsburg, Nicholasville, Winchester,
Hodgenville, Lebanon, Danville, Lancaster, Richmond, Morgantown,
Brownsville, Horse Cave, Greensburg, Campbellsville, Liberty,
Stanford, Russellville, Bowling Green, Franklin, Providence,
Scottsville, Glasgow, Tompkinsville, Edmonton, Columbia, Jamestown,
Burkesville, and Albany
326 PM EDT Thu Oct 7 2021 /226 PM CDT Thu Oct 7 2021/

This hazardous weather outlook is for portions of south central
Indiana and Central Kentucky.

.DAY ONE...Tonight.

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not anticipated.

KDW

Special Weather Statement
National Weather Service Louisville KY
550 PM EDT Thu Oct 7 2021

KYZ038-045-072215-
Spencer KY-Nelson KY-
550 PM EDT Thu Oct 7 2021

...A strong thunderstorm will impact portions of southern Spencer and
northeastern Nelson Counties through 615 PM EDT...

At 548 PM EDT, Doppler radar was tracking a strong thunderstorm 9
miles southeast of Taylorsville, moving northwest at 25 mph.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
  Chaplin, Bloomfield, and Wakefield.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, seek shelter inside a building.

&&

LAT...LON 3809 8522 3791 8515 3790 8515 3789 8518
      3788 8519 3790 8520 3788 8520 3786 8525
      3787 8525 3786 8526 3785 8528 3799 8544
      3809 8524
TIME...MOT...LOC 2148Z 148DEG 21KT 3792 8523

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

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