Severe Thunderstorm Warning 140, NWS Louisville, KY

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
117 PM EDT Mon Jun 8 2015

...Updated Aviation Discussion...

...Forecast Update...
Updated at 1207 PM EDT Mon Jun 8 2015

The forecast is largely on track early this afternoon.  As expected,
the cloud cover has continued to hold on and is just now beginning
to thin across portions of western KY.  Think this is where the
beginning of any stronger convection will develop, as low-level
instability is highest in this region (KCKV at 84/73 this hour).  In
fact, a strong storm was developing along the KY/TN border near
Murray, KY as of this writing.  Even with the cloud cover, forcing
from a seasonably strong mid-level wave should help compensate a bit
and should help initiate strong to locally severe storms across
western KY, spreading into central/southern KY this afternoon.
Think the risk for northern KY and southern IN continues to remain a
bit lower given the cloud cover.  Damaging winds continue to be the
main threat, along with marginally severe hail.  Any tornado threat
will likely be confined to boundary interactions as the ambient
environment is not overly favorable.  That being said, there are
several boundaries in the area that will need to be monitored,
especially across southern KY.

Updated 915 AM EDT Mon Jun 8 2015

The forecast this morning is largely on track, just went ahead and
updated the forecast to reflect the latest radar trends.  Convection
continues to blossom early this morning in response to a veering
low-level jet impinging on multiple outflow boundaries left over by
overnight convection across IN/IL.  Given the generally uncapped
atmosphere, this convection has been rather "messy" and currently
does not have much organization to it.

With the ongoing convection has come an extensive cloud shield,
which currently encompasses much of southern IN and central KY.
This cloud cover is rather thick, and will likely limit
destabilization especially across southern IN and northern KY.  For
this reason, agree with SPC's decision to hedge the Slight Risk
further to the south.  Many of the hi-res ensembles suggest that the
outflow boundary(s) will serve as the effective boundary(s) this
afternoon, which will keep the focus across central and especially
southern KY.  Can't completely rule out some atmospheric recovery
further north along the synoptic front where the forcing will be
better, but we will need to quickly erode quite a bit of cloud cover
for that to happen.  Nevertheless, any storms that do develop will
have access to 30-40 knots of deep-layer shear.  0-3km shear vectors
will be oriented WSW to NNE at 15 to 20 knots, so bowing segments
that can orient themselves this way will have the best potential for
damaging winds.

.SHORT TERM (Now through Tuesday)...
Issued at 305 AM EDT Mon Jun 8 2015

Leading convective line over southern Indiana is becoming
outflow-dominated and dying out as it tries to push into the I-64
corridor. The behavior of this line and the stratiform precip to the
north will make all the difference in the timing and placement of
likely strong to severe storms later today.

Confidence is limited given the model discrepancies that are already
in play, but still believe that we will have two opportunities for
convective initiation. The first will be on the outflow from the
ongoing storms, and by the time we do start to fire off storms, that
will most likely be solidly into central Kentucky. The second
opportunity will come later this afternoon with the cold front, and
will be dependent on whether the atmosphere can reload across
southern Indiana and north central Kentucky. Either way, there is
plenty of forcing aloft to support strong storms, most likely in the
form of another squall line. Low-level shear isn't overly
impressive, but between the potential for boundary interactions and
LCLs easily dropping to 800m AGL (if you believe the GFS), it's hard
to rule out mesovortex spin-ups.

Front will push through this evening, with convection exiting to the
southeast. However, lingering precip chances will carry through most
of the night in south-central and east-central KY, and the low-level
air mass isn't that much less humid than what we had over the
weekend. Temps continue on the high side of climo for Mon night/Tue,
pretty well in line with MOS and raw model consensus.

.LONG TERM (Tuesday Night through Sunday)...
Issued at 325 AM EDT Mon Jun 8 2015

Tuesday Night - Thursday Night...

The upper flow will transition from dry NW behind the departing
trough Tuesday night, to weak flow between between stronger
westerlies to the north and a SE CONUS ridge through mid week. This
will result in a dry period due to the relative lack of any
noticeable synoptic triggers. Will make note of a frontal boundary
stalling across central IL/IN/OH, and a very weak upper low over the
lower Mississippi River Valley. The Ohio River Valley will be
sandwiched between these two features, although the upper low may
throw just enough moisture into our southern counties on Thursday
for an isolated shower or storm.

Otherwise, expect a mostly sunny and warm period. Highs Wednesday
and Thursday should reach into the upper 80s to around 90 given H85
temps in the upper teens and good heating. Overnight lows will also
become steadily milder going from the low and mid 60s on Tuesday
night to the upper 60s to around 70 by Thursday night.

Friday - Sunday

The SE CONUS ridge will retrograde and become re-established over
the Gulf Coast states in response to a shortwave digging through New
England. This will bring more Gulf moisture into the Ohio River
Valley due to weak SW flow through a deep layer. The end result will
be a continued warm pattern with mainly diurnally driven scattered
thunderstorm chances through weekend. Coverage of storms may need to
be increased along the placement of a surface frontal boundary that
looks  to stall out along the northern periphery of the upper ridge,
which happens to be our northern CWA. So, forecast will generally
call for 40-50% coverage of afternoon/evening storms mainly across
the NE half of the CWA with Iso-Sct (20-30%) coverage across our
south. These orientations are subject to change based on where the
frontal boundary ends up positioning itself.

The placement of this boundary will also have an effect on
temperatures as areas south of the boundary should stay relatively
dry and warmer. Upper 80s to around 90 south, with low and mid 80s
expected north in more clouds/convection.

&&

.AVIATION (18Z TAF Update)...
Updated at 115 PM EDT Mon Jun 8 2015

Convection will likely affect all TAFs this afternoon, bringing
localized MVFR to IFR conditions.  However, outside of any
convection, conditions are expected to remain VFR with WSW winds
increasing to around 10-15 knots.  Have timed in the best chances
for storms in TEMPO groups at KLEX and KBWG, but admittedly
confidence in exact timing is low given there are several bands of
storms.  Will amend as needed.  KSDF will likely remain out of the
strongest and best coverage of storms, thus have just stuck with
VCTS wording there.

Convection will push southeast of all terminals this evening,
leaving partly cloudy to mostly clear skies.  Some light fog will be
possible at KBWG and KLEX, but synoptic winds should stay up just
enough (especially at KLEX) to preclude any dense fog development.

&&

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

Update.........KJD
Short Term.....RAS
Long Term......BJS
Aviation.......KJD

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LOUISVILLE KY
1227 PM CDT MON JUN 8 2015

KYZ082-081755-
CLINTON KY-
1227 PM CDT MON JUN 8 2015

...STRONG THUNDERSTORM WITH DANGEROUS LIGHTNING...HEAVY RAIN...AND
40 MPH WINDS...

AT 1225 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING
A STRONG THUNDERSTORM NEAR ALBANY...AND MOVING EAST AT 30 MPH.

OCCASIONAL LIGHTNING...HEAVY RAIN REDUCING VISIBILITIES...HALF INCH
HAIL...AND GUSTY WINDS OF AROUND 35 TO 40 MPH...ARE EXPECTED WITH
THIS STORM.

* THIS STORM WILL ALSO IMPACT...
  ALBANY...
  SAVAGE AND CARTWRIGHT...
  ALPHA AND NORA...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF ON OR NEAR A LAKE...RIVER...OR SWIMMING POOL...GET OUT OF THE
WATER AND MOVE INDOORS OR INSIDE A VEHICLE NOW. DON'T BE CAUGHT ON
THE WATER IN A THUNDERSTORM.

&&

LAT...LON 3662 8525 3669 8527 3678 8524 3682 8504
      3680 8501 3676 8500 3670 8502 3668 8500
      3663 8500 3663 8498 3661 8498
TIME...MOT...LOC 1727Z 258DEG 26KT 3670 8514

04

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LOUISVILLE KY
136 PM CDT MON JUN 8 2015

KYZ073>075-081-081905-
ALLEN KY-BARREN KY-CUMBERLAND KY-MONROE KY-
136 PM CDT MON JUN 8 2015

...STRONG THUNDERSTORM WITH DANGEROUS LIGHTNING...MODERATE RAIN...AND
50 MPH WINDS...

AT 134 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
STRONG THUNDERSTORM 6 MILES SOUTHEAST OF SCOTTSVILLE...AND MOVING
EAST AT 35 MPH.

CLOUD TO GROUND LIGHTNING...MODERATE RAIN REDUCING
VISIBILITIES...AND STRONG GUSTY WINDS OF AROUND 45 TO 50 MPH...ARE
EXPECTED WITH THIS STORM.

* THIS STORM WILL ALSO IMPACT...
  TOMPKINSVILLE...
  HOLLAND AND WALNUT HILL...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE AWARE THAT A GUST FRONT PRECEDING THIS STORM WILL GENERATE STRONG
AND GUSTY WINDS WELL BEFORE THE ARRIVAL OF ANY RAIN.

IF YOU ARE IN THE PATH OF THIS STORM...SEEK SHELTER INDOORS AND STAY
AWAY FROM WINDOWS. STAY TUNED TO NOAA ALL HAZARDS RADIO...
WEATHER.GOV/LOUISVILLE ON THE INTERNET...OR LOCAL MEDIA FOR LATER
UPDATES AND POSSIBLE WARNINGS.

&&

LAT...LON 3662 8588 3664 8618 3683 8607 3684 8562
      3682 8559 3684 8558 3684 8547 3661 8544
TIME...MOT...LOC 1836Z 286DEG 2KT 3672 8609

JDG

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE LOUISVILLE KY
143 PM CDT MON JUN 8 2015

KYZ070-081910-
LOGAN KY-
143 PM CDT MON JUN 8 2015

...THUNDERSTORM WITH DANGEROUS LIGHTNING...HEAVY RAIN...AND UP TO
HALF INCH HAIL AND 40 MPH WINDS...

AT 140 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR WAS TRACKING A
THUNDERSTORM 5 MILES NORTHEAST OF ELKTON...AND MOVING EAST AT 40 TO
50 MPH.

FREQUENT CLOUD TO GROUND LIGHTNING...BRIEF VERY HEAVY RAIN...HALF
INCH HAIL...AND GUSTY WINDS OF AROUND 35 TO 40 MPH...ARE EXPECTED
WITH THIS STORM.

* THIS STORM WILL ALSO IMPACT...
  RUSSELLVILLE...
  DANBY AND CAVE SPRINGS...
  DENNIS AND CORINTH...
  AUBURN...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...SEEK SHELTER INDOORS. STAY
TUNED TO NOAA ALL HAZARDS RADIO...WEATHER.GOV/LOUISVILLE ON THE
INTERNET...OR LOCAL MEDIA FOR LATER UPDATES.

&&

LAT...LON 3692 8706 3698 8666 3695 8664 3690 8662
      3688 8664 3684 8669 3682 8670 3675 8675
      3677 8706 3686 8707
TIME...MOT...LOC 1842Z 270DEG 45KT 3684 8705

TWF