Special Weather Statement, NWS Louisville, KY

Area Forecast Discussion
National Weather Service Louisville KY
330 PM EDT Thu Aug 3 2017

.Short Term (Now through Friday Night)...
Issued at 315 PM EDT Thu Aug 3 2017

Main weather player in the next 24 hrs is an upper shortwave trof
digging into the Upper Midwest and driving a surface cold front into
the Upper Mississippi Valley. Ahead of it, a fairly sloppy pattern
remains in place over the Ohio Valley today with weak SW flow in a
deep layer of the atmosphere. We have seen a few isolated
thunderstorms pop in the heat of the early afternoon, but with
substantially less coverage compared to yesterday. Slight chances of
storms will persist until just before sunset. We don't expect any
strong or severe storms, but can't rule out some heavy rain
producers as movement is fairly slow and the atmosphere is still
juicy.

The evening looks dry but precip chances will ramp up toward morning
as the front impinges on the area from the NW. A weakening line of
thunderstorms will likely approach the Ohio River around daybreak,
but the weakening trend does limit our precip chances to around 50%.
After an early morning minimum, POPs will increase mid/late morning,
with 60-70% chances east of Interstate 65. Severe chances quite
limited by the timing coinciding with a diurnal minimum of
instability, but there is a Marginal risk east of a line from
Glasgow to Versailles. Damaging winds will be the main threat with
the strongest storms as mid-level winds hit 35 kt. Just enough
elevated instability for marginal hail, but should be progressive
enough to limit the excessive rain potential.

Cooler and drier air will spill into the area fairly quickly behind
the departing front. Max temps will only recover by about 10 degrees
from morning lows, but the more noticeable change will be the drop
in dewpoints. Friday night skies will clear to allow a fall-like
radiational cooling night, with most locations dropping into the
50s. Louisville may even get in on the act, but the climate sites
should all remain just above daily record lows, which are in the
lower/mid 50s.

.Long Term (Saturday through Thursday)...
Issued at 305 PM EDT Thu Aug 3 2017

Canadian high pressure will continue the early fall temperatures on
Saturday, with highs just either side of 80 in spite of abundant
sunshine, and low humidity. A southern-stream disturbance ejecting
out of the Plains will bring increasing clouds and warmer temps Sat
night, and then increasing rain chances during the day on Sunday.
Precip chances will peak Sunday night and Monday as a stronger
northern-stream wave swings through the Great Lakes, and taps into
the moisture drawn north by the lead disturbance.

From Monday night onward, we get into a progressive pattern and a
series of disturbances will interact with a nearly stationary front
somewhere near the Tennessee Valley. This will be just far enough
north, with just enough uncertainty to support a 20-30% POP across
south-central Kentucky, while keeping the forecast mainly dry across
southern Indiana and north-central Kentucky. Temps will be near
climo at night and a few degrees below normal in the daytime as
clouds will limit diurnal ranges.

&&

.Aviation (18Z TAF Update)...
Issued at 121 PM EDT Thu Aug 3 2017

Isolated to scattered afternoon showers and thunderstorms will
develop again today, with the best chances for storms along and east
of I-65. Much like yesterday, the heavier showers and storms could
drop cigs/vis to IFR/MVFR briefly. Showers and thunderstorms should
subside this evening shortly after sunset. A cold front will
approach from the northwest early tomorrow morning, and a line of
showers and storms will be possible ahead of it. Have introduced -
SHRA and VCTS into TAF sites, though confidence in timing of front
is still low.

&&

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

Short Term........RAS
Long Term.........RAS
Aviation..........DM

Hazardous Weather Outlook
National Weather Service Louisville KY
345 PM EDT Thu Aug 3 2017

INZ076>079-083-084-089>092-KYZ023>043-045>049-053>057-061>067-
070>078-081-082-041945-
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
345 PM EDT Thu Aug 3 2017 /245 PM CDT Thu Aug 3 2017/

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

.DAY ONE...Tonight.

Isolated thunderstorms will be possible across the outlook area
through early evening. Any storm will be capable of producing
brief heavy rainfall, intense cloud to ground lightning, and locally
gusty winds.

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

Numerous thunderstorms will affect the region on Friday as a cold
front moves through the area. The best chance for strong or severe
storms will be east of a line from Glasgow to Frankfort, where
damaging winds and hail will be possible with the strongest storms.
Any thunderstorm will be capable of producing brief heavy rainfall
and lightning.

Scattered thunderstorms will also be possible Sunday and into Monday
as another weather system moves across the outlook area.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be requested over the next few days.

&&

More information, along with other weather, hydrological and
climate information can be found, at weather.gov/louisville.

RAS

Special Weather Statement
National Weather Service Louisville KY
404 PM EDT THU AUG 3 2017

KYZ031>033-032030-
Oldham-Henry-Trimble-
404 PM EDT THU AUG 3 2017

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN OLDHAM...SOUTH
CENTRAL TRIMBLE AND WEST CENTRAL HENRY COUNTIES...

At 403 PM EDT, a strong thunderstorm was located near La Grange,
moving northeast at 15 mph.

Winds in excess of 40 mph and torrential rainfall are possible with
this storm, especially along I-71.

Locations impacted include...
La Grange, New Castle, Pendleton, Russell Corner, Sligo, Sulphur,
Liro and Tarascon.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 3836 8538 3843 8544 3856 8527 3844 8513
TIME...MOT...LOC 2003Z 235DEG 14KT 3844 8533

DM

Special Weather Statement
National Weather Service Louisville KY
436 PM EDT THU AUG 3 2017

KYZ031-033-032100-
Oldham-Henry-
436 PM EDT THU AUG 3 2017

...A STRONG THUNDERSTORM WILL AFFECT EAST CENTRAL OLDHAM AND
SOUTHWESTERN HENRY COUNTIES...

At 436 PM EDT, a strong thunderstorm was located over La Grange,
moving east at 20 mph.

Winds in excess of 40 mph and pea size hail are possible with this
storm.

Locations impacted include...
La Grange, Pendleton, Eminence, Smithfield, Ballardsville, Liro,
Tarascon, Centerfield and Buckner.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 3835 8541 3843 8543 3851 8523 3837 8517
TIME...MOT...LOC 2036Z 253DEG 15KT 3840 8533

DM

Special Weather Statement
National Weather Service Louisville KY
458 PM EDT THU AUG 3 2017

KYZ033-032115-
Henry-
458 PM EDT THU AUG 3 2017

...A STRONG THUNDERSTORM WILL AFFECT SOUTHWESTERN HENRY COUNTY...

At 457 PM EDT, a strong thunderstorm was located near New Castle,
moving east at 20 mph.

Wind gusts up to 50 mph, half inch hail, and torrential rainfall are
possible with this storm.

Locations impacted include...
New Castle, Pendleton, Eminence, Smithfield, Tarascon and Bellview.

Torrential rainfall is occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 3852 8512 3835 8513 3836 8528 3839 8531
      3846 8534
TIME...MOT...LOC 2057Z 266DEG 15KT 3841 8525

DM

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOUISVILLE KY
526 PM EDT THU AUG 3 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0526 PM     FLASH FLOOD      3 SSW SLIGO             38.44N 85.34W
08/03/2017                   OLDHAM             KY   LAW ENFORCEMENT

            REPORTS OF FLASH FLOODING AND HIGH WATER
            OVER ROADWAY.

&&

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LOUISVILLE KY
527 PM EDT THU AUG 3 2017

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0527 PM     FLASH FLOOD      3 SSW SULPHUR           38.45N 85.29W
08/03/2017                   HENRY              KY   CO-OP OBSERVER

            HIGH WATER AND PONDING OVER HWY 153.

&&

Special Weather Statement
National Weather Service Louisville KY
547 PM EDT THU AUG 3 2017

KYZ031-032-032215-
Oldham-Trimble-
547 PM EDT THU AUG 3 2017

...A STRONG THUNDERSTORM WILL AFFECT NORTHERN OLDHAM AND SOUTHERN
TRIMBLE COUNTIES...

At 547 PM EDT, a strong thunderstorm was located near La Grange,
moving northeast at 25 mph.

Winds in excess of 30 mph are possible with this storm.

Locations impacted include...
Bedford, Owen, Westport, Halls Landing, Oldham, Greenhaven, Monitor,
Russell Corner, Skylight and Cedar Point.

Torrential rainfall is also occurring with this storm, and may cause
localized flooding. Do not drive your vehicle through flooded
roadways.

LAT...LON 3867 8527 3860 8522 3858 8521 3858 8520
      3857 8519 3839 8549 3843 8557 3846 8554
      3847 8550 3850 8548 3853 8542 3856 8541
      3868 8528
TIME...MOT...LOC 2147Z 231DEG 20KT 3845 8545

ZT