000
FXUS63 KLMK 220056
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
856 PM EDT TUE MAY 21 2013

.Forecast Update...
Issued at 855 PM EDT Tue May 21 2013

The next line of storms on radar will be moving into western
portions of the forecast area within the next hour. The strongest
portion of this line is at the northern end and this area should
track along and north of the Ohio River. How long this system holds
together is somewhat in question. Most mesoscale models show it
weakening as it continues east tonight and becoming more scattered
in nature. The models don`t have a great handle on the ongoing
strength. However, the general trend seems reasonable. The next line
of storms will them move in towards morning as a weak LLJ develops
and a shortwave approaches. Rather than try and time this out
specifically, have kept pops in the likely category for most of the
night across the western portion of the forecast area. Further east
the precipitation chances will be more scattered in nature overnight.

Issued at 630 PM EDT Tue May 21 2013

The storms have moved out of the area this evening and the Severe
Thunderstorm Watch has been cancelled. The next batch of storms is
just starting to move into far western Kentucky this evening. These
storms are expected to move into the forecast area late this evening
and into the overnight hours. Have adjusted pops down over the next
few hours before ramping them up again overnight. Updates are
already out.

&&

.Short Term (Tonight through Wednesday night)...
Issued at 315 PM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

A parade of MCSs has taken shape in the WSW flow from the southern
Plains into the Ohio and Tennessee Valleys. One MCS dissipated as it
moved across Kentucky this morning, and the next MCS in line has a
leading convective line extending from just SE of Elizabethtown,
southward into middle Tennessee. Near-severe wind gusts have been
observed already, and the potential remains for SVR winds in an
unstable and mostly unidirectionally-sheared environment. Hail is a
lesser threat, and tornado threat will be very minimal.

Expect showers and storms to continue for the next few hours, and
will try to delineate between the more numerous storms south of the
Bluegrass Parkway and the hit-and-miss activity that remains
possible farther north, but has not developed yet.

The evening looks to be dry as the heating of the day will be lost,
and we will be in a lull between systems. POPs will ramp up again
toward morning, especially in the west as low-level jetting
increases and fuels yet another MCS.

Tomorrow morning will look fairly similar to this morning, only with
the MCS closer to central Kentucky and probably lasting longer as
the low-level jet is a bit more persistent just ahead of the front.
MCS should still weaken or dissipate by midday, but will again leave
behind plenty of boundaries in an juicy environment. This bodes well
for re-development in the heat of the afternoon, which supports
likely POPs again.

Precip will diminish from west to east, mainly Wednesday evening as
the front pushes in and deeper moisture is shunted to our south and
east.

Not much confidence in the temp forecast as it will be modulated by
clouds and precip. Expect mins in the lower/mid 60s, with daytime
temps hitting 80. Max temps have the higher bust potential, as too
much rain will keep us in the mid 70s, while substantial breaks of
sunshine will give us mid 80s.

.Long Term (Thursday - Tuesday)...
Issued at 300 PM EDT Tue May 21 2013

At the start of the long-term period, the slow moving cold front
that is currently across the Plains and Middle Mississippi Valley
will be exiting our forecast area to the east. The convection
associated with the front will be pushed east and we should start
Thursday dry. However, the upper trough axis will be swinging across
the forecast area during the afternoon hours. Believe some
low-topped showers will develop in afternoon, which could produce
locally gusty winds. There could be some thunder with these showers,
but it will be isolated as cloud tops will be around or just
slightly above the freezing level. Breezy southwest winds will
become northwesterly through the day Thursday, with high
temperatures ranging from the upper 60s to middle 70s.

Distinctly cooler air with low dewpoints will continue through the
weekend, as high pressure of Canadian origin builds southward
through the Mississippi Valley Friday and into the Ohio Valley for
the holiday weekend. Despite clearing skies, Friday will stay quite
cool, with highs ranging from the middle 60s to right around 70
degrees. Temperatures will slowly moderate to low 70s in our north
to upper 70s in our south by Sunday, as ridging aloft edges back
over the Ohio Valley. Overnight lows during the weekend will be
rather cool with the low humidity. Expect lows around 50 degrees
Saturday morning, rising into the middle 50s Sunday morning.

By late Sunday, ridging will strengthen across the southern Plains,
with northwest flow aloft developing across the Ohio Valley. A warm
front will move northward across the forecast area, with moisture
beginning to pool late Sunday along and north of this boundary. The
warm front is expected to stretch along a line from Iowa southeast
through northern Kentucky Monday and shift north Tuesday. However,
there is a lot of model spread associated with the placement of this
boundary. The placement is significant because isolated to scattered
convection is expected to periodically develop along this boundary
and propagate in waves southeastward late Sunday through Monday and
perhaps even into Tuesday. This will spread showers and storms
across the region, but timing and locations to be impacted are much
in question. So, will continue with the running forecast of a slight
chance.

As for temperatures Monday through Tuesday, we should see a warm up
if heights aloft increase and the warm front lifts north. Will go
with high temperatures ranging from the middle 70s to lower 80s, but
this has a high bust potential if waves of storms track across the
region and cloud cover inundates the forecast area.

&&

.Aviation (00Z TAF Issuance)...
Issued at 722 PM EDT Tue May 21 2013

The TAF forecast remains tricky in regards to convection as there are
several waves of thunderstorms which may affect the sites over the
next 24-36 hours. The most immediate concern is the line of
thunderstorms currently in western KY. Many of the models have this
line weakening as it moves east. However, still think it will affect
SDF and BWG overnight. Timing the line at its current speed puts it
in to these sites between 04-05Z. Have therefore adjusted the TSRA
in the TAFs to reflect this. Beyond this time frame, additional
thunderstorms do look like they may develop towards the morning
hours. However, with uncertainty of development will carry VCTS
after 07Z through the mid morning hours. There should then be a lull
before redevelopment may occur Wednesday afternoon. Will keep the
latter portion of the TAF period dry for now, but thunderstorms may
need to be added as confidence in the forecast increases. Storms at
LEX will be more scattered in nature, especially during the first
half of the TAF period so will keep prevailing TSRA out of the TAFs
there for now.

The other concern for tomorrow will be the development of gusty
winds. Winds will strengthen out of the south through the morning
hours, with gusts in the 20-25 knot range expected.

&&

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


Update...........EER
Short Term.......RAS
Long Term........MJP
Aviation.........EER

000
FXUS63 KLMK 212324
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
724 PM EDT TUE MAY 21 2013

...Updated Aviation Discussion...

.Forecast Update...
Issued at 630 PM EDT Tue May 21 2013

The storms have moved out of the area this evening and the Severe
Thunderstorm Watch has been cancelled. The next batch of storms is
just starting to move into far western Kentucky this evening. These
storms are expected to move into the forecast area late this evening
and into the overnight hours. Have adjusted pops down over the next
few hours before ramping them up again overnight. Updates are
already out.

&&

.Short Term (Tonight through Wednesday night)...
Issued at 315 PM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

A parade of MCSs has taken shape in the WSW flow from the southern
Plains into the Ohio and Tennessee Valleys. One MCS dissipated as it
moved across Kentucky this morning, and the next MCS in line has a
leading convective line extending from just SE of Elizabethtown,
southward into middle Tennessee. Near-severe wind gusts have been
observed already, and the potential remains for SVR winds in an
unstable and mostly unidirectionally-sheared environment. Hail is a
lesser threat, and tornado threat will be very minimal.

Expect showers and storms to continue for the next few hours, and
will try to delineate between the more numerous storms south of the
Bluegrass Parkway and the hit-and-miss activity that remains
possible farther north, but has not developed yet.

The evening looks to be dry as the heating of the day will be lost,
and we will be in a lull between systems. POPs will ramp up again
toward morning, especially in the west as low-level jetting
increases and fuels yet another MCS.

Tomorrow morning will look fairly similar to this morning, only with
the MCS closer to central Kentucky and probably lasting longer as
the low-level jet is a bit more persistent just ahead of the front.
MCS should still weaken or dissipate by midday, but will again leave
behind plenty of boundaries in an juicy environment. This bodes well
for re-development in the heat of the afternoon, which supports
likely POPs again.

Precip will diminish from west to east, mainly Wednesday evening as
the front pushes in and deeper moisture is shunted to our south and
east.

Not much confidence in the temp forecast as it will be modulated by
clouds and precip. Expect mins in the lower/mid 60s, with daytime
temps hitting 80. Max temps have the higher bust potential, as too
much rain will keep us in the mid 70s, while substantial breaks of
sunshine will give us mid 80s.

.Long Term (Thursday - Tuesday)...
Issued at 300 PM EDT Tue May 21 2013

At the start of the long-term period, the slow moving cold front
that is currently across the Plains and Middle Mississippi Valley
will be exiting our forecast area to the east. The convection
associated with the front will be pushed east and we should start
Thursday dry. However, the upper trough axis will be swinging across
the forecast area during the afternoon hours. Believe some
low-topped showers will develop in afternoon, which could produce
locally gusty winds. There could be some thunder with these showers,
but it will be isolated as cloud tops will be around or just
slightly above the freezing level. Breezy southwest winds will
become northwesterly through the day Thursday, with high
temperatures ranging from the upper 60s to middle 70s.

Distinctly cooler air with low dewpoints will continue through the
weekend, as high pressure of Canadian origin builds southward
through the Mississippi Valley Friday and into the Ohio Valley for
the holiday weekend. Despite clearing skies, Friday will stay quite
cool, with highs ranging from the middle 60s to right around 70
degrees. Temperatures will slowly moderate to low 70s in our north
to upper 70s in our south by Sunday, as ridging aloft edges back
over the Ohio Valley. Overnight lows during the weekend will be
rather cool with the low humidity. Expect lows around 50 degrees
Saturday morning, rising into the middle 50s Sunday morning.

By late Sunday, ridging will strengthen across the southern Plains,
with northwest flow aloft developing across the Ohio Valley. A warm
front will move northward across the forecast area, with moisture
beginning to pool late Sunday along and north of this boundary. The
warm front is expected to stretch along a line from Iowa southeast
through northern Kentucky Monday and shift north Tuesday. However,
there is a lot of model spread associated with the placement of this
boundary. The placement is significant because isolated to scattered
convection is expected to periodically develop along this boundary
and propagate in waves southeastward late Sunday through Monday and
perhaps even into Tuesday. This will spread showers and storms
across the region, but timing and locations to be impacted are much
in question. So, will continue with the running forecast of a slight
chance.

As for temperatures Monday through Tuesday, we should see a warm up
if heights aloft increase and the warm front lifts north. Will go
with high temperatures ranging from the middle 70s to lower 80s, but
this has a high bust potential if waves of storms track across the
region and cloud cover inundates the forecast area.

&&

.Aviation (00Z TAF Issuance)...
Issued at 722 PM EDT Tue May 21 2013

The TAF forecast remains tricky in regards to convection as there are
several waves of thunderstorms which may affect the sites over the
next 24-36 hours. The most immediate concern is the line of
thunderstorms currently in western KY. Many of the models have this
line weakening as it moves east. However, still think it will affect
SDF and BWG overnight. Timing the line at its current speed puts it
in to these sites between 04-05Z. Have therefore adjusted the TSRA
in the TAFs to reflect this. Beyond this time frame, additional
thunderstorms do look like they may develop towards the morning
hours. However, with uncertainty of development will carry VCTS
after 07Z through the mid morning hours. There should then be a lull
before redevelopment may occur Wednesday afternoon. Will keep the
latter portion of the TAF period dry for now, but thunderstorms may
need to be added as confidence in the forecast increases. Storms at
LEX will be more scattered in nature, especially during the first
half of the TAF period so will keep prevailing TSRA out of the TAFs
there for now.

The other concern for tomorrow will be the development of gusty
winds. Winds will strengthen out of the south through the morning
hours, with gusts in the 20-25 knot range expected.

&&

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


Update...........EER
Short Term.......RAS
Long Term........MJP
Aviation.........EER

000
FXUS63 KLMK 212231
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
631 PM EDT TUE MAY 21 2013

.Forecast Update...
Issued at 630 PM EDT Tue May 21 2013

The storms have moved out of the area this evening and the Severe
Thunderstorm Watch has been cancelled. The next batch of storms is
just starting to move into far western Kentucky this evening. These
storms are expected to move into the forecast area late this evening
and into the overnight hours. Have adjusted pops down over the next
few hours before ramping them up again overnight. Updates are
already out.

&&

.Short Term (Tonight through Wednesday night)...
Issued at 315 PM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

A parade of MCSs has taken shape in the WSW flow from the southern
Plains into the Ohio and Tennessee Valleys. One MCS dissipated as it
moved across Kentucky this morning, and the next MCS in line has a
leading convective line extending from just SE of Elizabethtown,
southward into middle Tennessee. Near-severe wind gusts have been
observed already, and the potential remains for SVR winds in an
unstable and mostly unidirectionally-sheared environment. Hail is a
lesser threat, and tornado threat will be very minimal.

Expect showers and storms to continue for the next few hours, and
will try to delineate between the more numerous storms south of the
Bluegrass Parkway and the hit-and-miss activity that remains
possible farther north, but has not developed yet.

The evening looks to be dry as the heating of the day will be lost,
and we will be in a lull between systems. POPs will ramp up again
toward morning, especially in the west as low-level jetting
increases and fuels yet another MCS.

Tomorrow morning will look fairly similar to this morning, only with
the MCS closer to central Kentucky and probably lasting longer as
the low-level jet is a bit more persistent just ahead of the front.
MCS should still weaken or dissipate by midday, but will again leave
behind plenty of boundaries in an juicy environment. This bodes well
for re-development in the heat of the afternoon, which supports
likely POPs again.

Precip will diminish from west to east, mainly Wednesday evening as
the front pushes in and deeper moisture is shunted to our south and
east.

Not much confidence in the temp forecast as it will be modulated by
clouds and precip. Expect mins in the lower/mid 60s, with daytime
temps hitting 80. Max temps have the higher bust potential, as too
much rain will keep us in the mid 70s, while substantial breaks of
sunshine will give us mid 80s.

.Long Term (Thursday - Tuesday)...
Issued at 300 PM EDT Tue May 21 2013

At the start of the long-term period, the slow moving cold front
that is currently across the Plains and Middle Mississippi Valley
will be exiting our forecast area to the east. The convection
associated with the front will be pushed east and we should start
Thursday dry. However, the upper trough axis will be swinging across
the forecast area during the afternoon hours. Believe some
low-topped showers will develop in afternoon, which could produce
locally gusty winds. There could be some thunder with these showers,
but it will be isolated as cloud tops will be around or just
slightly above the freezing level. Breezy southwest winds will
become northwesterly through the day Thursday, with high
temperatures ranging from the upper 60s to middle 70s.

Distinctly cooler air with low dewpoints will continue through the
weekend, as high pressure of Canadian origin builds southward
through the Mississippi Valley Friday and into the Ohio Valley for
the holiday weekend. Despite clearing skies, Friday will stay quite
cool, with highs ranging from the middle 60s to right around 70
degrees. Temperatures will slowly moderate to low 70s in our north
to upper 70s in our south by Sunday, as ridging aloft edges back
over the Ohio Valley. Overnight lows during the weekend will be
rather cool with the low humidity. Expect lows around 50 degrees
Saturday morning, rising into the middle 50s Sunday morning.

By late Sunday, ridging will strengthen across the southern Plains,
with northwest flow aloft developing across the Ohio Valley. A warm
front will move northward across the forecast area, with moisture
beginning to pool late Sunday along and north of this boundary. The
warm front is expected to stretch along a line from Iowa southeast
through northern Kentucky Monday and shift north Tuesday. However,
there is a lot of model spread associated with the placement of this
boundary. The placement is significant because isolated to scattered
convection is expected to periodically develop along this boundary
and propagate in waves southeastward late Sunday through Monday and
perhaps even into Tuesday. This will spread showers and storms
across the region, but timing and locations to be impacted are much
in question. So, will continue with the running forecast of a slight
chance.

As for temperatures Monday through Tuesday, we should see a warm up
if heights aloft increase and the warm front lifts north. Will go
with high temperatures ranging from the middle 70s to lower 80s, but
this has a high bust potential if waves of storms track across the
region and cloud cover inundates the forecast area.

&&

.Aviation (18Z TAF Issuance)...
Issued at 115 PM EDT Tue May 21 2013

Still a tricky TAF set, but we seem to be coming into line with
previously advertised conditions as we get enough sunshine to
support heating.  Will initialize BWG with VCTS as a cluster of
storms makes its way east along the KY/TN border. Any direct impact
on the airport will be too brief to carry in the TAF. Convection has
yet to get going near SDF or LEX, but as temperatures warm we do
expect scattered storms to develop. As we are still a few degrees
shy of convective temps, will keep with the previous idea of
introducing VCTS beginning around 20-21Z.

Still looking for this activity to diminish after sunset with the
loss of heating. Will re-introduce precip as prevailing TSRA around
or just after midnight as the nose of a 40-50 kt low-level jet finds
its way into Kentucky. Will most likely see brief restrictions of
MVFR or even IFR later in the night, but look for prevailing VFR for
the vast majority of the time.

The latter few hours of the TAFs on Wednesday morning will be a lull
between complexes, with dry weather and VFR conditions. Only real
concern in this period will be SSW winds gusting into the 20-25 kt
range.

&&

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


Update...........EER
Short Term.......RAS
Long Term........MJP
Aviation.........RAS

000
FXUS63 KLMK 211931
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
331 PM EDT TUE MAY 21 2013

.Short Term (Tonight through Wednesday night)...
Issued at 315 PM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

A parade of MCSs has taken shape in the WSW flow from the southern
Plains into the Ohio and Tennessee Valleys. One MCS dissipated as it
moved across Kentucky this morning, and the next MCS in line has a
leading convective line extending from just SE of Elizabethtown,
southward into middle Tennessee. Near-severe wind gusts have been
observed already, and the potential remains for SVR winds in an
unstable and mostly unidirectionally-sheared environment. Hail is a
lesser threat, and tornado threat will be very minimal.

Expect showers and storms to continue for the next few hours, and
will try to delineate between the more numerous storms south of the
Bluegrass Parkway and the hit-and-miss activity that remains
possible farther north, but has not developed yet.

The evening looks to be dry as the heating of the day will be lost,
and we will be in a lull between systems. POPs will ramp up again
toward morning, especially in the west as low-level jetting
increases and fuels yet another MCS.

Tomorrow morning will look fairly similar to this morning, only with
the MCS closer to central Kentucky and probably lasting longer as
the low-level jet is a bit more persistent just ahead of the front.
MCS should still weaken or dissipate by midday, but will again leave
behind plenty of boundaries in an juicy environment. This bodes well
for re-development in the heat of the afternoon, which supports
likely POPs again.

Precip will diminish from west to east, mainly Wednesday evening as
the front pushes in and deeper moisture is shunted to our south and
east.

Not much confidence in the temp forecast as it will be modulated by
clouds and precip. Expect mins in the lower/mid 60s, with daytime
temps hitting 80. Max temps have the higher bust potential, as too
much rain will keep us in the mid 70s, while substantial breaks of
sunshine will give us mid 80s.

.Long Term (Thursday - Tuesday)...
Issued at 300 PM EDT Tue May 21 2013

At the start of the long-term period, the slow moving cold front
that is currently across the Plains and Middle Mississippi Valley
will be exiting our forecast area to the east. The convection
associated with the front will be pushed east and we should start
Thursday dry. However, the upper trough axis will be swinging across
the forecast area during the afternoon hours. Believe some
low-topped showers will develop in afternoon, which could produce
locally gusty winds. There could be some thunder with these showers,
but it will be isolated as cloud tops will be around or just
slightly above the freezing level. Breezy southwest winds will
become northwesterly through the day Thursday, with high
temperatures ranging from the upper 60s to middle 70s.

Distinctly cooler air with low dewpoints will continue through the
weekend, as high pressure of Canadian origin builds southward
through the Mississippi Valley Friday and into the Ohio Valley for
the holiday weekend. Despite clearing skies, Friday will stay quite
cool, with highs ranging from the middle 60s to right around 70
degrees. Temperatures will slowly moderate to low 70s in our north
to upper 70s in our south by Sunday, as ridging aloft edges back
over the Ohio Valley. Overnight lows during the weekend will be
rather cool with the low humidity. Expect lows around 50 degrees
Saturday morning, rising into the middle 50s Sunday morning.

By late Sunday, ridging will strengthen across the southern Plains,
with northwest flow aloft developing across the Ohio Valley. A warm
front will move northward across the forecast area, with moisture
beginning to pool late Sunday along and north of this boundary. The
warm front is expected to stretch along a line from Iowa southeast
through northern Kentucky Monday and shift north Tuesday. However,
there is a lot of model spread associated with the placement of this
boundary. The placement is significant because isolated to scattered
convection is expected to periodically develop along this boundary
and propagate in waves southeastward late Sunday through Monday and
perhaps even into Tuesday. This will spread showers and storms
across the region, but timing and locations to be impacted are much
in question. So, will continue with the running forecast of a slight
chance.

As for temperatures Monday through Tuesday, we should see a warm up
if heights aloft increase and the warm front lifts north. Will go
with high temperatures ranging from the middle 70s to lower 80s, but
this has a high bust potential if waves of storms track across the
region and cloud cover inundates the forecast area.

&&

.Aviation (18Z TAF Issuance)...
Issued at 115 PM EDT Tue May 21 2013

Still a tricky TAF set, but we seem to be coming into line with
previously advertised conditions as we get enough sunshine to
support heating.  Will initialize BWG with VCTS as a cluster of
storms makes its way east along the KY/TN border. Any direct impact
on the airport will be too brief to carry in the TAF. Convection has
yet to get going near SDF or LEX, but as temperatures warm we do
expect scattered storms to develop. As we are still a few degrees
shy of convective temps, will keep with the previous idea of
introducing VCTS beginning around 20-21Z.

Still looking for this activity to diminish after sunset with the
loss of heating. Will re-introduce precip as prevailing TSRA around
or just after midnight as the nose of a 40-50 kt low-level jet finds
its way into Kentucky. Will most likely see brief restrictions of
MVFR or even IFR later in the night, but look for prevailing VFR for
the vast majority of the time.

The latter few hours of the TAFs on Wednesday morning will be a lull
between complexes, with dry weather and VFR conditions. Only real
concern in this period will be SSW winds gusting into the 20-25 kt
range.

&&

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


Short Term.......RAS
Long Term........MJP
Aviation.........RAS

000
FXUS63 KLMK 211730
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
129 PM EDT TUE MAY 21 2013

...Updated Aviation Discussion...
.Forecast Update...
Issued at 905 AM EDT Tue May 21 2013

Precip from the overnight MCS is dissipating over central Kentucky
as we speak. Expect to see a break in the action for the next few
hrs, but we remain in a juicy air mass and a boundary-rich
environment. No changes to the afternoon forecast for scattered
shower/T-storm activity, nor the potential for these storms to pulse
up to marginal SVR levels. Expect to update text and point-and-click
within the next hour, after we give this dissipating trend a little
more time.

&&

.Short Term (Today - Wednesday)...
Issued at 251 AM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

Early this morning a long line of showers and thunderstorms
stretched from Michigan to Oklahoma.  This line will weaken
considerably as it pushes to the southeast away from the jet energy
that was supporting it earlier.  Will have likely PoPs in southwest
Indiana before dawn, and just chance PoPs across the area after dawn
as the line continues to fall apart.

We should see a break in the action for several hours before
redevelopment takes place this afternoon.  Widespread clouds and
scattered morning showers will prevent us from destabilizing fully,
but some strong storms could still fire in the warm and juicy
atmosphere. It will be interesting to see where the outflow boundary
from this morning`s convection ends up, as that could serve as a
focus for renewed convection.  As for any severe weather, it looks
like marginally severe hail is the primary threat, with marginally
severe wind gusts a secondary threat.  Tornadoes look unlikely,
though local boundary intersections will need to be watched for the
possibility of a brief spin-up.

We may see another break this evening as afternoon convection
wanes.  Renewed shower and thunderstorm activity is then expected
during the late night hours as a low level jet revs up from Memphis
to Fort Wayne.  A strong low level inversion is forecast to set up,
so small hail would be the main threat with any stronger storms.

On Wednesday the cold front that has been producing the rough
weather across the nation`s midsection recently will draw nearer
still to the LMK CWA, reaching the lower Wabash and middle
Mississippi Valleys by evening.  Additional shower and thunderstorm
development can be expected on Wednesday, particularly in the
afternoon.  Once again, widespread morning clouds and scattered
showers will prevent us from destabilizing much.  A few strong
storms will still be possible, though, with marginally severe hail
as the primary threat...marginally severe wind gusts secondary...and
tornadoes unlikely other than where local boundaries meet.

Temperatures are also very challenging given the clouds and rain.
For today will shoot for highs mostly in the middle 80s, though that
may be generous if we don`t get some sun this afternoon.  Muggy lows
tonight will be in the middle and upper 60s once again.  Model data
vary widely on how warm we will get on Wednesday.  For now will go
with highs around 80.

.Long Term (Wednesday Night through Monday)...
Issued at 245 AM EDT Tue May 21 2013

Upper air pattern at 500mb late Wednesday is forecast to become
somewhat amplified with thin ridging across the northern plains
sandwiched between a deep closed low off the Pacific Northwest coast
and a slow moving trough centered over the western Great Lakes. This
Great Lakes trough will deepen, with its base swinging across the
Commonwealth by early Friday morning. Showers and thunderstorms
Wednesday will diminish during the evening hours and overnight as
veering mid-level winds will bring lower PWATs east from Missouri.
PWATs of 1.6 inches earlier Wednesday will diminish to under one
inch by dawn Thursday. Still, will maintain at least a chance of
showers and an isolated thunderstorms overnight through Thursday
morning.

By late Thursday, a surface trough will move southeast of the Ohio
River, switching our winds to the northwest and eventually bringing
in substantially cooler air. Despite less available moisture, the
presence of the 500mb trough axis and a diffuse frontal boundary
will not preclude scattered low topped showers and isolated thunder
Thursday afternoon.

High pressure of Canadian origin will build southward along the
Mississippi Valley Friday, sliding east towards Ohio by Sunday
morning. Distinctly cooler air with low dewpoints will arrive by
Friday morning and continue through the entire weekend. Despite
clearing skies, Friday will stay quite cool and refreshing, with
highs only rising into the lower 70s at best. We can expect several
cool nights from Friday to Monday mornings with lows initially
around 50, rising into the upper 50s by Monday morning. Under mostly
clear skies, highs Saturday and Sunday will remain in the 70s.

By late Sunday, a slowly progressive 500mb wave pattern will have
moved the Great Lakes trough eastwards over New England. Ridging
will begin to build across the southern Plains, with northwest flow
developing across the Lower Ohio Valley. Moisture will begin to pool
late Sunday along and north of a warm front expected to develop
along a line from Iowa southeast through northern Kentucky. Will
introduce a chance for isolated to scattered convection late Sunday
and Monday, especially across our northern counties. Humidities will
also rise by Monday as southwesterly surface winds develop.

&&

.Aviation (18Z TAF Issuance)...
Issued at 115 PM EDT Tue May 21 2013

Still a tricky TAF set, but we seem to be coming into line with
previously advertised conditions as we get enough sunshine to
support heating.  Will initialize BWG with VCTS as a cluster of
storms makes its way east along the KY/TN border. Any direct impact
on the airport will be too brief to carry in the TAF. Convection has
yet to get going near SDF or LEX, but as temperatures warm we do
expect scattered storms to develop. As we are still a few degrees
shy of convective temps, will keep with the previous idea of
introducing VCTS beginning around 20-21Z.

Still looking for this activity to diminish after sunset with the
loss of heating. Will re-introduce precip as prevailing TSRA around
or just after midnight as the nose of a 40-50 kt low-level jet finds
its way into Kentucky. Will most likely see brief restrictions of
MVFR or even IFR later in the night, but look for prevailing VFR for
the vast majority of the time.

The latter few hours of the TAFs on Wednesday morning will be a lull
between complexes, with dry weather and VFR conditions. Only real
concern in this period will be SSW winds gusting into the 20-25 kt
range.

&&

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


Update...........RAS
Short Term.......13
Long Term........JSD
Aviation.........RAS

000
FXUS63 KLMK 211314
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
914 AM EDT TUE MAY 21 2013

.Forecast Update...
Issued at 905 AM EDT Tue May 21 2013

Precip from the overnight MCS is dissipating over central Kentucky
as we speak. Expect to see a break in the action for the next few
hrs, but we remain in a juicy air mass and a boundary-rich
environment. No changes to the afternoon forecast for scattered
shower/T-storm activity, nor the potential for these storms to pulse
up to marginal SVR levels. Expect to update text and point-and-click
within the next hour, after we give this dissipating trend a little
more time.

&&

.Short Term (Today - Wednesday)...
Issued at 251 AM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

Early this morning a long line of showers and thunderstorms
stretched from Michigan to Oklahoma.  This line will weaken
considerably as it pushes to the southeast away from the jet energy
that was supporting it earlier.  Will have likely PoPs in southwest
Indiana before dawn, and just chance PoPs across the area after dawn
as the line continues to fall apart.

We should see a break in the action for several hours before
redevelopment takes place this afternoon.  Widespread clouds and
scattered morning showers will prevent us from destabilizing fully,
but some strong storms could still fire in the warm and juicy
atmosphere. It will be interesting to see where the outflow boundary
from this morning`s convection ends up, as that could serve as a
focus for renewed convection.  As for any severe weather, it looks
like marginally severe hail is the primary threat, with marginally
severe wind gusts a secondary threat.  Tornadoes look unlikely,
though local boundary intersections will need to be watched for the
possibility of a brief spin-up.

We may see another break this evening as afternoon convection
wanes.  Renewed shower and thunderstorm activity is then expected
during the late night hours as a low level jet revs up from Memphis
to Fort Wayne.  A strong low level inversion is forecast to set up,
so small hail would be the main threat with any stronger storms.

On Wednesday the cold front that has been producing the rough
weather across the nation`s midsection recently will draw nearer
still to the LMK CWA, reaching the lower Wabash and middle
Mississippi Valleys by evening.  Additional shower and thunderstorm
development can be expected on Wednesday, particularly in the
afternoon.  Once again, widespread morning clouds and scattered
showers will prevent us from destabilizing much.  A few strong
storms will still be possible, though, with marginally severe hail
as the primary threat...marginally severe wind gusts secondary...and
tornadoes unlikely other than where local boundaries meet.

Temperatures are also very challenging given the clouds and rain.
For today will shoot for highs mostly in the middle 80s, though that
may be generous if we don`t get some sun this afternoon.  Muggy lows
tonight will be in the middle and upper 60s once again.  Model data
vary widely on how warm we will get on Wednesday.  For now will go
with highs around 80.

.Long Term (Wednesday Night through Monday)...
Issued at 245 AM EDT Tue May 21 2013

Upper air pattern at 500mb late Wednesday is forecast to become
somewhat amplified with thin ridging across the northern plains
sandwiched between a deep closed low off the Pacific Northwest coast
and a slow moving trough centered over the western Great Lakes. This
Great Lakes trough will deepen, with its base swinging across the
Commonwealth by early Friday morning. Showers and thunderstorms
Wednesday will diminish during the evening hours and overnight as
veering mid-level winds will bring lower PWATs east from Missouri.
PWATs of 1.6 inches earlier Wednesday will diminish to under one
inch by dawn Thursday. Still, will maintain at least a chance of
showers and an isolated thunderstorms overnight through Thursday
morning.

By late Thursday, a surface trough will move southeast of the Ohio
River, switching our winds to the northwest and eventually bringing
in substantially cooler air. Despite less available moisture, the
presence of the 500mb trough axis and a diffuse frontal boundary
will not preclude scattered low topped showers and isolated thunder
Thursday afternoon.

High pressure of Canadian origin will build southward along the
Mississippi Valley Friday, sliding east towards Ohio by Sunday
morning. Distinctly cooler air with low dewpoints will arrive by
Friday morning and continue through the entire weekend. Despite
clearing skies, Friday will stay quite cool and refreshing, with
highs only rising into the lower 70s at best. We can expect several
cool nights from Friday to Monday mornings with lows initially
around 50, rising into the upper 50s by Monday morning. Under mostly
clear skies, highs Saturday and Sunday will remain in the 70s.

By late Sunday, a slowly progressive 500mb wave pattern will have
moved the Great Lakes trough eastwards over New England. Ridging
will begin to build across the southern Plains, with northwest flow
developing across the Lower Ohio Valley. Moisture will begin to pool
late Sunday along and north of a warm front expected to develop
along a line from Iowa southeast through northern Kentucky. Will
introduce a chance for isolated to scattered convection late Sunday
and Monday, especially across our northern counties. Humidities will
also rise by Monday as southwesterly surface winds develop.

&&

.Aviation (12Z TAF Issuance)...
Issued at 644 AM EDT Tue May 21 2013

A complex and, as a result, low confidence forecast.  A storm system
approaching from the Plains will throw unsettled weather at us
throughout the TAF period.

A line of storms is advancing into central Kentucky at 1045Z.  Have
used radar animations to bring this line into the TAF sites over the
next few hours.  The line should be weaker by the time it gets as
far east as the airports, and should be mostly in the form of
showers with isolated TSRA.  SDF stands the best chance at receiving
the most adverse weather from this line.

Once that clears out, we should have several quiet hours from mid
morning through mid afternoon.  The amount of destabilization we`ll
be able to realize this afternoon is in question, given the morning
clouds and showers.  Nevertheless, will forecast scattered
thunderstorm redevelopment during the heat of the day.  Winds may
get a little gusty this afternoon as well...especially if we can get
some decent sunshine.

Another quiet period is expected this evening as the afternoon
convection wanes.  Then, another round of showers and storms should
break out late tonight as the Plains storm system continues its
approach and a low level jet cranks up from Memphis to Toledo.

Needless to say, with all this going on, changes will certainly be
made to the TAFs over the course of the day.

&&

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


Update...........RAS
Short Term.......13
Long Term........JSD
Aviation.........13

000
FXUS63 KLMK 211046
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
645 AM EDT TUE MAY 21 2013

...Updated Aviation Discussion...



.Short Term (Today - Wednesday)...
Issued at 251 AM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

Early this morning a long line of showers and thunderstorms
stretched from Michigan to Oklahoma.  This line will weaken
considerably as it pushes to the southeast away from the jet energy
that was supporting it earlier.  Will have likely PoPs in southwest
Indiana before dawn, and just chance PoPs across the area after dawn
as the line continues to fall apart.

We should see a break in the action for several hours before
redevelopment takes place this afternoon.  Widespread clouds and
scattered morning showers will prevent us from destabilizing fully,
but some strong storms could still fire in the warm and juicy
atmosphere. It will be interesting to see where the outflow boundary
from this morning`s convection ends up, as that could serve as a
focus for renewed convection.  As for any severe weather, it looks
like marginally severe hail is the primary threat, with marginally
severe wind gusts a secondary threat.  Tornadoes look unlikely,
though local boundary intersections will need to be watched for the
possibility of a brief spin-up.

We may see another break this evening as afternoon convection
wanes.  Renewed shower and thunderstorm activity is then expected
during the late night hours as a low level jet revs up from Memphis
to Fort Wayne.  A strong low level inversion is forecast to set up,
so small hail would be the main threat with any stronger storms.

On Wednesday the cold front that has been producing the rough
weather across the nation`s midsection recently will draw nearer
still to the LMK CWA, reaching the lower Wabash and middle
Mississippi Valleys by evening.  Additional shower and thunderstorm
development can be expected on Wednesday, particularly in the
afternoon.  Once again, widespread morning clouds and scattered
showers will prevent us from destabilizing much.  A few strong
storms will still be possible, though, with marginally severe hail
as the primary threat...marginally severe wind gusts secondary...and
tornadoes unlikely other than where local boundaries meet.

Temperatures are also very challenging given the clouds and rain.
For today will shoot for highs mostly in the middle 80s, though that
may be generous if we don`t get some sun this afternoon.  Muggy lows
tonight will be in the middle and upper 60s once again.  Model data
vary widely on how warm we will get on Wednesday.  For now will go
with highs around 80.

.Long Term (Wednesday Night through Monday)...
Issued at 245 AM EDT Tue May 21 2013

Upper air pattern at 500mb late Wednesday is forecast to become
somewhat amplified with thin ridging across the northern plains
sandwiched between a deep closed low off the Pacific Northwest coast
and a slow moving trough centered over the western Great Lakes. This
Great Lakes trough will deepen, with its base swinging across the
Commonwealth by early Friday morning. Showers and thunderstorms
Wednesday will diminish during the evening hours and overnight as
veering mid-level winds will bring lower PWATs east from Missouri.
PWATs of 1.6 inches earlier Wednesday will diminish to under one
inch by dawn Thursday. Still, will maintain at least a chance of
showers and an isolated thunderstorms overnight through Thursday
morning.

By late Thursday, a surface trough will move southeast of the Ohio
River, switching our winds to the northwest and eventually bringing
in substantially cooler air. Despite less available moisture, the
presence of the 500mb trough axis and a diffuse frontal boundary
will not preclude scattered low topped showers and isolated thunder
Thursday afternoon.

High pressure of Canadian origin will build southward along the
Mississippi Valley Friday, sliding east towards Ohio by Sunday
morning. Distinctly cooler air with low dewpoints will arrive by
Friday morning and continue through the entire weekend. Despite
clearing skies, Friday will stay quite cool and refreshing, with
highs only rising into the lower 70s at best. We can expect several
cool nights from Friday to Monday mornings with lows initially
around 50, rising into the upper 50s by Monday morning. Under mostly
clear skies, highs Saturday and Sunday will remain in the 70s.

By late Sunday, a slowly progressive 500mb wave pattern will have
moved the Great Lakes trough eastwards over New England. Ridging
will begin to build across the southern Plains, with northwest flow
developing across the Lower Ohio Valley. Moisture will begin to pool
late Sunday along and north of a warm front expected to develop
along a line from Iowa southeast through northern Kentucky. Will
introduce a chance for isolated to scattered convection late Sunday
and Monday, especially across our northern counties. Humidities will
also rise by Monday as southwesterly surface winds develop.

&&

.Aviation (12Z TAF Issuance)...
Issued at 644 AM EDT Tue May 21 2013

A complex and, as a result, low confidence forecast.  A storm system
approaching from the Plains will throw unsettled weather at us
throughout the TAF period.

A line of storms is advancing into central Kentucky at 1045Z.  Have
used radar animations to bring this line into the TAF sites over the
next few hours.  The line should be weaker by the time it gets as
far east as the airports, and should be mostly in the form of
showers with isolated TSRA.  SDF stands the best chance at receiving
the most adverse weather from this line.

Once that clears out, we should have several quiet hours from mid
morning through mid afternoon.  The amount of destabilization we`ll
be able to realize this afternoon is in question, given the morning
clouds and showers.  Nevertheless, will forecast scattered
thunderstorm redevelopment during the heat of the day.  Winds may
get a little gusty this afternoon as well...especially if we can get
some decent sunshine.

Another quiet period is expected this evening as the afternoon
convection wanes.  Then, another round of showers and storms should
break out late tonight as the Plains storm system continues its
approach and a low level jet cranks up from Memphis to Toledo.

Needless to say, with all this going on, changes will certainly be
made to the TAFs over the course of the day.

&&

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


Short Term.......13
Long Term........JSD
Aviation.........13

000
FXUS63 KLMK 210958
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
558 AM EDT TUE MAY 21 2013

.Mesoscale Update...
Issued at 558 AM EDT Tue May 21 2013

Raised PoPs for much of the CWA as a line of showers and storms
races eastward from western Kentucky toward southern Indiana and
central Kentucky.  The line is expected to diminish as it moves
east, but our western one or two tiers of counties should still see
widespread convection.  The line has had a history of winds to
nearly 50 mph, though winds are not expected to be that strong by
the time it gets this far east...probably more in the 30 to 40 mph
range along the western LMK CWA border from Jasper to Russellville.

Of most concern is storms along the northern half of the line that
will be moving along the east-west outflow boundaries put out by
showers and storms that came in from the northwest a few hours ago.
At 10Z the east-west boundaries stretched roughly from Frankfort to
Elizabethtown to Owensboro.  Storms riding along those boundaries
will have an increased chance of low level rotation.

&&

.Short Term (Today - Wednesday)...
Issued at 251 AM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

Early this morning a long line of showers and thunderstorms
stretched from Michigan to Oklahoma.  This line will weaken
considerably as it pushes to the southeast away from the jet energy
that was supporting it earlier.  Will have likely PoPs in southwest
Indiana before dawn, and just chance PoPs across the area after dawn
as the line continues to fall apart.

We should see a break in the action for several hours before
redevelopment takes place this afternoon.  Widespread clouds and
scattered morning showers will prevent us from destabilizing fully,
but some strong storms could still fire in the warm and juicy
atmosphere. It will be interesting to see where the outflow boundary
from this morning`s convection ends up, as that could serve as a
focus for renewed convection.  As for any severe weather, it looks
like marginally severe hail is the primary threat, with marginally
severe wind gusts a secondary threat.  Tornadoes look unlikely,
though local boundary intersections will need to be watched for the
possibility of a brief spin-up.

We may see another break this evening as afternoon convection
wanes.  Renewed shower and thunderstorm activity is then expected
during the late night hours as a low level jet revs up from Memphis
to Fort Wayne.  A strong low level inversion is forecast to set up,
so small hail would be the main threat with any stronger storms.

On Wednesday the cold front that has been producing the rough
weather across the nation`s midsection recently will draw nearer
still to the LMK CWA, reaching the lower Wabash and middle
Mississippi Valleys by evening.  Additional shower and thunderstorm
development can be expected on Wednesday, particularly in the
afternoon.  Once again, widespread morning clouds and scattered
showers will prevent us from destabilizing much.  A few strong
storms will still be possible, though, with marginally severe hail
as the primary threat...marginally severe wind gusts secondary...and
tornadoes unlikely other than where local boundaries meet.

Temperatures are also very challenging given the clouds and rain.
For today will shoot for highs mostly in the middle 80s, though that
may be generous if we don`t get some sun this afternoon.  Muggy lows
tonight will be in the middle and upper 60s once again.  Model data
vary widely on how warm we will get on Wednesday.  For now will go
with highs around 80.

.Long Term (Wednesday Night through Monday)...
Issued at 245 AM EDT Tue May 21 2013

Upper air pattern at 500mb late Wednesday is forecast to become
somewhat amplified with thin ridging across the northern plains
sandwiched between a deep closed low off the Pacific Northwest coast
and a slow moving trough centered over the western Great Lakes. This
Great Lakes trough will deepen, with its base swinging across the
Commonwealth by early Friday morning. Showers and thunderstorms
Wednesday will diminish during the evening hours and overnight as
veering mid-level winds will bring lower PWATs east from Missouri.
PWATs of 1.6 inches earlier Wednesday will diminish to under one
inch by dawn Thursday. Still, will maintain at least a chance of
showers and an isolated thunderstorms overnight through Thursday
morning.

By late Thursday, a surface trough will move southeast of the Ohio
River, switching our winds to the northwest and eventually bringing
in substantially cooler air. Despite less available moisture, the
presence of the 500mb trough axis and a diffuse frontal boundary
will not preclude scattered low topped showers and isolated thunder
Thursday afternoon.

High pressure of Canadian origin will build southward along the
Mississippi Valley Friday, sliding east towards Ohio by Sunday
morning. Distinctly cooler air with low dewpoints will arrive by
Friday morning and continue through the entire weekend. Despite
clearing skies, Friday will stay quite cool and refreshing, with
highs only rising into the lower 70s at best. We can expect several
cool nights from Friday to Monday mornings with lows initially
around 50, rising into the upper 50s by Monday morning. Under mostly
clear skies, highs Saturday and Sunday will remain in the 70s.

By late Sunday, a slowly progressive 500mb wave pattern will have
moved the Great Lakes trough eastwards over New England. Ridging
will begin to build across the southern Plains, with northwest flow
developing across the Lower Ohio Valley. Moisture will begin to pool
late Sunday along and north of a warm front expected to develop
along a line from Iowa southeast through northern Kentucky. Will
introduce a chance for isolated to scattered convection late Sunday
and Monday, especially across our northern counties. Humidities will
also rise by Monday as southwesterly surface winds develop.

&&

.Aviation (06Z TAF Issuance)...
Issued at 117 AM EDT Tue May 21 2013

A complex and, as a result, low confidence forecast.  A storm system
approaching from the Plains will throw unsettled weather at us
throughout the TAF period.

Of first concern is the possibility of LLWS early this morning.
Looking at KLVX VWP and surface obs, it looks like there is little
to no directional shear and borderline speed shear, so will leave
LLWS out of the TAFs for now.

A line of storms is advancing across Illinois at 05Z.  Have used
radar animations to bring this line into the TAF sites over the next
several hours.  The line should be weaker by the time it gets this
far east, and should be mostly in the form of showers with isolated
TSRA.

Once that clears out, we should have several quiet hours from mid
morning through mid afternoon.  The amount of destabilization we`ll
be able to realize is in question, given the morning clouds and
showers.  Nevertheless, will forecast scattered thunderstorm
redevelopment during the heat of the day.  Winds may get a little
gusty this afternoon as well...especially if we can get some decent
sunshine.

Another quiet period is expected this evening as the afternoon
convection wanes.  Then, another round of showers and storms should
break out late tonight as the Plains storm system continues its
approach and a low level jet cranks up from Memphis to Fort Wayne.

Needless to say, with all this going on, changes will certainly be
made to the TAFs over the course of the day.

&&

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


Mesoscale........13
Short Term.......13
Long Term........JSD
Aviation.........13

000
FXUS63 KLMK 210654
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
253 AM EDT TUE MAY 21 2013

.Short Term (Today - Wednesday)...
Issued at 251 AM EDT Tue May 21 2013

A difficult and complicated forecast as a storm system approaches
from the Plains...

Early this morning a long line of showers and thunderstorms
stretched from Michigan to Oklahoma.  This line will weaken
considerably as it pushes to the southeast away from the jet energy
that was supporting it earlier.  Will have likely PoPs in southwest
Indiana before dawn, and just chance PoPs across the area after dawn
as the line continues to fall apart.

We should see a break in the action for several hours before
redevelopment takes place this afternoon.  Widespread clouds and
scattered morning showers will prevent us from destabilizing fully,
but some strong storms could still fire in the warm and juicy
atmosphere. It will be interesting to see where the outflow boundary
from this morning`s convection ends up, as that could serve as a
focus for renewed convection.  As for any severe weather, it looks
like marginally severe hail is the primary threat, with marginally
severe wind gusts a secondary threat.  Tornadoes look unlikely,
though local boundary intersections will need to be watched for the
possibility of a brief spin-up.

We may see another break this evening as afternoon convection
wanes.  Renewed shower and thunderstorm activity is then expected
during the late night hours as a low level jet revs up from Memphis
to Fort Wayne.  A strong low level inversion is forecast to set up,
so small hail would be the main threat with any stronger storms.

On Wednesday the cold front that has been producing the rough
weather across the nation`s midsection recently will draw nearer
still to the LMK CWA, reaching the lower Wabash and middle
Mississippi Valleys by evening.  Additional shower and thunderstorm
development can be expected on Wednesday, particularly in the
afternoon.  Once again, widespread morning clouds and scattered
showers will prevent us from destabilizing much.  A few strong
storms will still be possible, though, with marginally severe hail
as the primary threat...marginally severe wind gusts secondary...and
tornadoes unlikely other than where local boundaries meet.

Temperatures are also very challenging given the clouds and rain.
For today will shoot for highs mostly in the middle 80s, though that
may be generous if we don`t get some sun this afternoon.  Muggy lows
tonight will be in the middle and upper 60s once again.  Model data
vary widely on how warm we will get on Wednesday.  For now will go
with highs around 80.


.Long Term (Wednesday Night through Monday)...
Issued at 245 AM EDT Tue May 21 2013

Upper air pattern at 500mb late Wednesday is forecast to become
somewhat amplified with thin ridging across the northern plains
sandwiched between a deep closed low off the Pacific Northwest coast
and a slow moving trough centered over the western Great Lakes. This
Great Lakes trough will deepen, with its base swinging across the
Commonwealth by early Friday morning. Showers and thunderstorms
Wednesday will diminish during the evening hours and overnight as
veering mid-level winds will bring lower PWATs east from Missouri.
PWATs of 1.6 inches earlier Wednesday will diminish to under one
inch by dawn Thursday. Still, will maintain at least a chance of
showers and an isolated thunderstorms overnight through Thursday
morning.

By late Thursday, a surface trough will move southeast of the Ohio
River, switching our winds to the northwest and eventually bringing
in substantially cooler air. Despite less available moisture, the
presence of the 500mb trough axis and a diffuse frontal boundary
will not preclude scattered low topped showers and isolated thunder
Thursday afternoon.

High pressure of Canadian origin will build southward along the
Mississippi Valley Friday, sliding east towards Ohio by Sunday
morning. Distinctly cooler air with low dewpoints will arrive by
Friday morning and continue through the entire weekend. Despite
clearing skies, Friday will stay quite cool and refreshing, with
highs only rising into the lower 70s at best. We can expect several
cool nights from Friday to Monday mornings with lows initially
around 50, rising into the upper 50s by Monday morning. Under mostly
clear skies, highs Saturday and Sunday will remain in the 70s.

By late Sunday, a slowly progressive 500mb wave pattern will have
moved the Great Lakes trough eastwards over New England. Ridging
will begin to build across the southern plains, with northwest flow
developing across the Lower Ohio Valley. Moisture will begin to pool
late Sunday along and north of a warm front expected to develop
along a line from Iowa southeast through northern Kentucky. Will
introduce a chance for isolated to scattered convection late Sunday
and Monday, especially across our northern counties. Humidities will
also rise by Monday as southwesterly surface winds develop.

&&

.Aviation (06Z TAF Issuance)...
Issued at 117 AM EDT Tue May 21 2013

A complex and, as a result, low confidence forecast.  A storm system
approaching from the Plains will throw unsettled weather at us
throughout the TAF period.

Of first concern is the possibility of LLWS early this morning.
Looking at KLVX VWP and surface obs, it looks like there is little
to no directional shear and borderline speed shear, so will leave
LLWS out of the TAFs for now.

A line of storms is advancing across Illinois at 05Z.  Have used
radar animations to bring this line into the TAF sites over the next
several hours.  The line should be weaker by the time it gets this
far east, and should be mostly in the form of showers with isolated
TSRA.

Once that clears out, we should have several quiet hours from mid
morning through mid afternoon.  The amount of destabilization we`ll
be able to realize is in question, given the morning clouds and
showers.  Nevertheless, will forecast scattered thunderstorm
redevelopment during the heat of the day.  Winds may get a little
gusty this afternoon as well...especially if we can get some decent
sunshine.

Another quiet period is expected this evening as the afternoon
convection wanes.  Then, another round of showers and storms should
break out late tonight as the Plains storm system continues its
approach and a low level jet cranks up from Memphis to Fort Wayne.

Needless to say, with all this going on, changes will certainly be
made to the TAFs over the course of the day.

&&

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


Short Term.......13
Long Term........JSD
Aviation.........13

000
FXUS63 KLMK 210518
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
118 AM EDT TUE MAY 21 2013

...Updated Aviation Discussion...

.Short Term (Now - Tuesday Night)...
Issued at 300 PM EDT Mon May 20 2013

Low-level debris clouds from convection across the Middle
Mississippi Valley overspread the Lower Ohio Valley early this
morning. This caused a slow warming trend through this afternoon.
However, clouds are breaking up with breezy south-southwest winds
aiding in mixing. Still some time for warming, with mid and upper
80s being common. Louisville could still make a run at 90, but
believe the record of 91 (1934) will remain. Latest guidance and
aircraft soundings continue to illustrate the ridge aloft has us
under a cap. A very thin line of light rain showers and isolated
thunderstorms has developed across eastern Illinois. This will have
a tough time reaching us this afternoon, but could skirt our
northern most counties this evening if it holds together. How much
the cap weakens between now and then will be the determining factor.
The best chance will be farther north in Indiana, where the cap is
weaker.

Heading into tonight and Tuesday, the upper-level ridge over our
area will break down as the central CONUS trough axis moves into the
eastern Plains and upper Midwest, where convection is expected to
develop this afternoon and evening. This upstream convection should
progress eastward into the Ohio Valley late tonight. Latest guidance
indicates this activity should approach the forecast area in a
weakening state during the pre-dawn hours. However, westerlies are
increasing and the ridge aloft will be weakening, so some storms may
hold on. This convection should wane early Tuesday, but will leave
plenty of mesoscale boundaries around the region.

Additional development is expected in the afternoon and evening hours
Tuesday, to our west along a frontal boundary and over our area with
the remnant mesoscale boundaries. SPC has placed areas along and
west of a Bowling Green to Frankfort line in a slight risk. With
increasing 0-6km bulk shear of around 25-35 knots and strongly
unstable airmass, multicell clusters would be the convective mode.
Heavy rainfall and cloud to ground lightning, along with isolated
large hail and damaging winds will be the main threats. So, severe
storms are possible Tuesday afternoon and evening. The convection
will push east and weaken in strength, but some models are
indicating another round of showers and thunderstorms late Tuesday
night. Will not get too fancy with the PoP forecast given great
uncertainty among models with timing of these events.

As for temperatures, we will remain rather mild tonight, with temps
ranging from the middle 60s to lower 70s. Highs Tuesday will be
cooler with the potential outflow/convection in the morning, debris
clouds, and the ridge axis having shifted east. Middle to upper 80s
and humid conditions are on tap. Temperatures Tuesday night should
remain mild, as temperatures drop into the middle and upper 60s.

.Long Term (Wednesday through Monday)...
Issued at 255 PM EDT Mon May 20 2013

Unsettled weather is expected Wednesday and Thursday, in association
with a slow and complex frontal passage. The best chances for precip
and the strongest storms will be on Wednesday, with a deep
southwesterly moisture feed across the Ohio Valley. Not too excited
about SVR potential as instability will be the limiting factor and
our best guess is that precip will already be ongoing at daybreak.
Still, it merits likely POPs through the day on Wednesday.

Much lower POPs on Wednesday night as the deep moisture will be
shunted to our south and east. Will see high-end chance POPs again
on Thursday as the positively-tilted upper trough swings through the
Great Lakes and the Ohio Valley, and decent low-level moisture
remains in place. Best rain chances will be over the Bluegrass,
closer to the more favorable dynamics. This activity will be
shallower and less intense than any storms we see on Wednesday.
Temps through Thursday will be near normal by day, and a few degrees
above normal by night due to a moist air mass and abundant cloud
cover.

Upper trough axis will slip to our east by Thursday evening, opening
the door for a very mild area of Canadian high pressure.
Picture-postcard weather is on tap for Friday and Saturday with
plenty of sunshine, temps a few degrees below normal, and low
humidity.

Temps will recover to near normal during the latter half of the
holiday weekend. However there is some question as to where a
backdoor front will set up, and how efficiently that will focus
precip. Therefore will include a slight chance of showers and storms
from Saturday night onward.

&&

.Aviation (06Z TAF Issuance)...
Issued at 117 AM EDT Tue May 21 2013

A complex and, as a result, low confidence forecast.  A storm system
approaching from the Plains will throw unsettled weather at us
throughout the TAF period.

Of first concern is the possibility of LLWS early this morning.
Looking at KLVX VWP and surface obs, it looks like there is little
to no directional shear and borderline speed shear, so will leave
LLWS out of the TAFs for now.

A line of storms is advancing across Illinois at 05Z.  Have used
radar animations to bring this line into the TAF sites over the next
several hours.  The line should be weaker by the time it gets this
far east, and should be mostly in the form of showers with isolated
TSRA.

Once that clears out, we should have several quiet hours from mid
morning through mid afternoon.  The amount of destabilization we`ll
be able to realize is in question, given the morning clouds and
showers.  Nevertheless, will forecast scattered thunderstorm
redevelopment during the heat of the day.  Winds may get a little
gusty this afternoon as well...especially if we can get some decent
sunshine.

Another quiet period is expected this evening as the afternoon
convection wanes.  Then, another round of showers and storms should
break out late tonight as the Plains storm system continues its
approach and a low level jet cranks up from Memphis to Fort Wayne.

Needless to say, with all this going on, changes will certainly be
made to the TAFs over the course of the day.

&&

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


Short Term.......MJP
Long Term........RAS
Aviation.........13

000
FXUS63 KLMK 210154
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
954 PM EDT MON MAY 20 2013

.Forecast Update...
Issued at 950 PM EDT Mon May 20 2013

The ongoing line of thunderstorms stretching from IL to TX will
continue to move east overnight. The latest models have the remnants
of this system moving into the forecast after 06Z tonight and most
of them have th bulk of the storms moving in after 09Z. Have
therefore pushed back the precipitation chances in the forecast
until after 06Z. The line is expected to weaken as it moves into the
forecast area. However, some strong storms will still be a
possibility early tomorrow morning, particularly across southern
Indiana. An isolated severe thunderstorm or two may be possible
across our farthest northwest counties. The threats with any strong
to severe storms still look to be hail and gusty winds.

&&

.Short Term (Now - Tuesday Night)...
Issued at 300 PM EDT Mon May 20 2013

Low-level debris clouds from convection across the Middle
Mississippi Valley overspread the Lower Ohio Valley early this
morning. This caused a slow warming trend through this afternoon.
However, clouds are breaking up with breezy south-southwest winds
aiding in mixing. Still some time for warming, with mid and upper
80s being common. Louisville could still make a run at 90, but
believe the record of 91 (1934) will remain. Latest guidance and
aircraft soundings continue to illustrate the ridge aloft has us
under a cap. A very thin line of light rain showers and isolated
thunderstorms has developed across eastern Illinois. This will have
a tough time reaching us this afternoon, but could skirt our
northern most counties this evening if it holds together. How much
the cap weakens between now and then will be the determining factor.
The best chance will be farther north in Indiana, where the cap is
weaker.

Heading into tonight and Tuesday, the upper-level ridge over our
area will break down as the central CONUS trough axis moves into the
eastern Plains and upper Midwest, where convection is expected to
develop this afternoon and evening. This upstream convection should
progress eastward into the Ohio Valley late tonight. Latest guidance
indicates this activity should approach the forecast area in a
weakening state during the pre-dawn hours. However, westerlies are
increasing and the ridge aloft will be weakening, so some storms may
hold on. This convection should wane early Tuesday, but will leave
plenty of mesoscale boundaries around the region.

Additional development is expected in the afternoon and evening hours
Tuesday, to our west along a frontal boundary and over our area with
the remnant mesoscale boundaries. SPC has placed areas along and
west of a Bowling Green to Frankfort line in a slight risk. With
increasing 0-6km bulk shear of around 25-35 knots and strongly
unstable airmass, multicell clusters would be the convective mode.
Heavy rainfall and cloud to ground lightning, along with isolated
large hail and damaging winds will be the main threats. So, severe
storms are possible Tuesday afternoon and evening. The convection
will push east and weaken in strength, but some models are
indicating another round of showers and thunderstorms late Tuesday
night. Will not get too fancy with the PoP forecast given great
uncertainty among models with timing of these events.

As for temperatures, we will remain rather mild tonight, with temps
ranging from the middle 60s to lower 70s. Highs Tuesday will be
cooler with the potential outflow/convection in the morning, debris
clouds, and the ridge axis having shifted east. Middle to upper 80s
and humid conditions are on tap. Temperatures Tuesday night should
remain mild, as temperatures drop into the middle and upper 60s.

.Long Term (Wednesday through Monday)...
Issued at 255 PM EDT Mon May 20 2013

Unsettled weather is expected Wednesday and Thursday, in association
with a slow and complex frontal passage. The best chances for precip
and the strongest storms will be on Wednesday, with a deep
southwesterly moisture feed across the Ohio Valley. Not too excited
about SVR potential as instability will be the limiting factor and
our best guess is that precip will already be ongoing at daybreak.
Still, it merits likely POPs through the day on Wednesday.

Much lower POPs on Wednesday night as the deep moisture will be
shunted to our south and east. Will see high-end chance POPs again
on Thursday as the positively-tilted upper trough swings through the
Great Lakes and the Ohio Valley, and decent low-level moisture
remains in place. Best rain chances will be over the Bluegrass,
closer to the more favorable dynamics. This activity will be
shallower and less intense than any storms we see on Wednesday.
Temps through Thursday will be near normal by day, and a few degrees
above normal by night due to a moist air mass and abundant cloud
cover.

Upper trough axis will slip to our east by Thursday evening, opening
the door for a very mild area of Canadian high pressure.
Picture-postcard weather is on tap for Friday and Saturday with
plenty of sunshine, temps a few degrees below normal, and low
humidity.

Temps will recover to near normal during the latter half of the
holiday weekend. However there is some question as to where a
backdoor front will set up, and how efficiently that will focus
precip. Therefore will include a slight chance of showers and storms
from Saturday night onward.

&&

.Aviation (00Z TAF Issuance)...
Issued at 720 PM EDT Mon May 20 2013

The main TAF concerns for this forecast period will be marginal LLWS
overnight tonight and then timing of convection for tomorrow.  A
potent low pressure system over the Plains states will continue to
make slow progress eastward toward the Midwest through tomorrow.
Ahead of this system, a 30-35 kt LLJ will get going tonight.
However, according to model soundings, the atmosphere should stay
mixy with sfc winds staying in the 7-11 kt range overnight and no
real good inversion becoming established.  Therefore, decided to
leave LLWS out of the TAFs at this point.

For tomorrow, waves of convection are expected to push through the
TAF sites.  According to the latest high-res model data, the first
wave should occur during the mid morning to early afternoon hours
with a second wave occurring during the evening hours.  Have tried
to indicate these 2 different waves especially in the longer SDF
TAF, but timing will likely need to be adjusted.  The strength of
these waves is in question as well.  We`ll likely see a broken line
of showers and t-storms during the first round tomorrow
morning/early afternoon, but just how intense this first wave will
be is still unknown.  Will need to monitor trends overnight as
convection heads this way.  Have remained on the conservative side
in the TAFs right now with VFR conditions, VCTS, and wind gusts
around 20 kts.  Look for further refinements to t-storm timing and
strength in coming TAF packages.

Sfc winds will generally remain out of the SSE this evening and then
shift to SSW during the early morning hours.  Wind gusts of 18-22
kts will be possible outside of any t-storm tomorrow afternoon.

&&

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


Update...........EER
Short Term.......MJP
Long Term........MJ
Aviation.........AMS

000
FXUS63 KLMK 202325
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
724 PM EDT MON MAY 20 2013

...Updated Aviation Discussion...

.Short Term (Now - Tuesday Night)...
Issued at 300 PM EDT Mon May 20 2013

Low-level debris clouds from convection across the Middle
Mississippi Valley overspread the Lower Ohio Valley early this
morning. This caused a slow warming trend through this afternoon.
However, clouds are breaking up with breezy south-southwest winds
aiding in mixing. Still some time for warming, with mid and upper
80s being common. Louisville could still make a run at 90, but
believe the record of 91 (1934) will remain. Latest guidance and
aircraft soundings continue to illustrate the ridge aloft has us
under a cap. A very thin line of light rain showers and isolated
thunderstorms has developed across eastern Illinois. This will have
a tough time reaching us this afternoon, but could skirt our
northern most counties this evening if it holds together. How much
the cap weakens between now and then will be the determining factor.
The best chance will be farther north in Indiana, where the cap is
weaker.

Heading into tonight and Tuesday, the upper-level ridge over our
area will break down as the central CONUS trough axis moves into the
eastern Plains and upper Midwest, where convection is expected to
develop this afternoon and evening. This upstream convection should
progress eastward into the Ohio Valley late tonight. Latest guidance
indicates this activity should approach the forecast area in a
weakening state during the pre-dawn hours. However, westerlies are
increasing and the ridge aloft will be weakening, so some storms may
hold on. This convection should wane early Tuesday, but will leave
plenty of mesoscale boundaries around the region.

Additional development is expected in the afternoon and evening hours
Tuesday, to our west along a frontal boundary and over our area with
the remnant mesoscale boundaries. SPC has placed areas along and
west of a Bowling Green to Frankfort line in a slight risk. With
increasing 0-6km bulk shear of around 25-35 knots and strongly
unstable airmass, multicell clusters would be the convective mode.
Heavy rainfall and cloud to ground lightning, along with isolated
large hail and damaging winds will be the main threats. So, severe
storms are possible Tuesday afternoon and evening. The convection
will push east and weaken in strength, but some models are
indicating another round of showers and thunderstorms late Tuesday
night. Will not get too fancy with the PoP forecast given great
uncertainty among models with timing of these events.

As for temperatures, we will remain rather mild tonight, with temps
ranging from the middle 60s to lower 70s. Highs Tuesday will be
cooler with the potential outflow/convection in the morning, debris
clouds, and the ridge axis having shifted east. Middle to upper 80s
and humid conditions are on tap. Temperatures Tuesday night should
remain mild, as temperatures drop into the middle and upper 60s.

.Long Term (Wednesday through Monday)...
Issued at 255 PM EDT Mon May 20 2013

Unsettled weather is expected Wednesday and Thursday, in association
with a slow and complex frontal passage. The best chances for precip
and the strongest storms will be on Wednesday, with a deep
southwesterly moisture feed across the Ohio Valley. Not too excited
about SVR potential as instability will be the limiting factor and
our best guess is that precip will already be ongoing at daybreak.
Still, it merits likely POPs through the day on Wednesday.

Much lower POPs on Wednesday night as the deep moisture will be
shunted to our south and east. Will see high-end chance POPs again
on Thursday as the positively-tilted upper trough swings through the
Great Lakes and the Ohio Valley, and decent low-level moisture
remains in place. Best rain chances will be over the Bluegrass,
closer to the more favorable dynamics. This activity will be
shallower and less intense than any storms we see on Wednesday.
Temps through Thursday will be near normal by day, and a few degrees
above normal by night due to a moist air mass and abundant cloud
cover.

Upper trough axis will slip to our east by Thursday evening, opening
the door for a very mild area of Canadian high pressure.
Picture-postcard weather is on tap for Friday and Saturday with
plenty of sunshine, temps a few degrees below normal, and low
humidity.

Temps will recover to near normal during the latter half of the
holiday weekend. However there is some question as to where a
backdoor front will set up, and how efficiently that will focus
precip. Therefore will include a slight chance of showers and storms
from Saturday night onward.

&&

.Aviation (00Z TAF Issuance)...
Issued at 720 PM EDT Mon May 20 2013

The main TAF concerns for this forecast period will be marginal LLWS
overnight tonight and then timing of convection for tomorrow.  A
potent low pressure system over the Plains states will continue to
make slow progress eastward toward the Midwest through tomorrow.
Ahead of this system, a 30-35 kt LLJ will get going tonight.
However, according to model soundings, the atmosphere should stay
mixy with sfc winds staying in the 7-11 kt range overnight and no
real good inversion becoming established.  Therefore, decided to
leave LLWS out of the TAFs at this point.

For tomorrow, waves of convection are expected to push through the
TAF sites.  According to the latest high-res model data, the first
wave should occur during the mid morning to early afternoon hours
with a second wave occurring during the evening hours.  Have tried
to indicate these 2 different waves especially in the longer SDF
TAF, but timing will likely need to be adjusted.  The strength of
these waves is in question as well.  We`ll likely see a broken line
of showers and t-storms during the first round tomorrow
morning/early afternoon, but just how intense this first wave will
be is still unknown.  Will need to monitor trends overnight as
convection heads this way.  Have remained on the conservative side
in the TAFs right now with VFR conditions, VCTS, and wind gusts
around 20 kts.  Look for further refinements to t-storm timing and
strength in coming TAF packages.

Sfc winds will generally remain out of the SSE this evening and then
shift to SSW during the early morning hours.  Wind gusts of 18-22
kts will be possible outside of any t-storm tomorrow afternoon.

&&

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


Short Term.......MJP
Long Term........RAS
Aviation.........AMS

000
FXUS63 KLMK 201905
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
305 PM EDT MON MAY 20 2013

.Short Term (Now - Tuesday Night)...
Issued at 300 PM EDT Mon May 20 2013

Low-level debris clouds from convection across the Middle
Mississippi Valley overspread the Lower Ohio Valley early this
morning. This caused a slow warming trend through this afternoon.
However, clouds are breaking up with breezy south-southwest winds
aiding in mixing. Still some time for warming, with mid and upper
80s being common. Louisville could still make a run at 90, but
believe the record of 91 (1934) will remain. Latest guidance and
aircraft soundings continue to illustrate the ridge aloft has us
under a cap. A very thin line of light rain showers and isolated
thunderstorms has developed across eastern Illinois. This will have
a tough time reaching us this afternoon, but could skirt our
northern most counties this evening if it holds together. How much
the cap weakens between now and then will be the determining factor.
The best chance will be farther north in Indiana, where the cap is
weaker.

Heading into tonight and Tuesday, the upper-level ridge over our
area will break down as the central CONUS trough axis moves into the
eastern Plains and upper Midwest, where convection is expected to
develop this afternoon and evening. This upstream convection should
progress eastward into the Ohio Valley late tonight. Latest guidance
indicates this activity should approach the forecast area in a
weakening state during the pre-dawn hours. However, westerlies are
increasing and the ridge aloft will be weakening, so some storms may
hold on. This convection should wane early Tuesday, but will leave
plenty of mesoscale boundaries around the region.

Additional development is expected in the afternoon and evening hours
Tuesday, to our west along a frontal boundary and over our area with
the remnant mesoscale boundaries. SPC has placed areas along and
west of a Bowling Green to Frankfort line in a slight risk. With
increasing 0-6km bulk shear of around 25-35 knots and strongly
unstable airmass, multicell clusters would be the convective mode.
Heavy rainfall and cloud to ground lightning, along with isolated
large hail and damaging winds will be the main threats. So, severe
storms are possible Tuesday afternoon and evening. The convection
will push east and weaken in strength, but some models are
indicating another round of showers and thunderstorms late Tuesday
night. Will not get too fancy with the PoP forecast given great
uncertainty among models with timing of these events.

As for temperatures, we will remain rather mild tonight, with temps
ranging from the middle 60s to lower 70s. Highs Tuesday will be
cooler with the potential outflow/convection in the morning, debris
clouds, and the ridge axis having shifted east. Middle to upper 80s
and humid conditions are on tap. Temperatures Tuesday night should
remain mild, as temperatures drop into the middle and upper 60s.

.Long Term (Wednesday through Monday)...
Issued at 255 PM EDT Mon May 20 2013

Unsettled weather is expected Wednesday and Thursday, in association
with a slow and complex frontal passage. The best chances for precip
and the strongest storms will be on Wednesday, with a deep
southwesterly moisture feed across the Ohio Valley. Not too excited
about SVR potential as instability will be the limiting factor and
our best guess is that precip will already be ongoing at daybreak.
Still, it merits likely POPs through the day on Wednesday.

Much lower POPs on Wednesday night as the deep moisture will be
shunted to our south and east. Will see high-end chance POPs again
on Thursday as the positively-tilted upper trough swings through the
Great Lakes and the Ohio Valley, and decent low-level moisture
remains in place. Best rain chances will be over the Bluegrass,
closer to the more favorable dynamics. This activity will be
shallower and less intense than any storms we see on Wednesday.
Temps through Thursday will be near normal by day, and a few degrees
above normal by night due to a moist air mass and abundant cloud
cover.

Upper trough axis will slip to our east by Thursday evening, opening
the door for a very mild area of Canadian high pressure.
Picture-postcard weather is on tap for Friday and Saturday with
plenty of sunshine, temps a few degrees below normal, and low
humidity.

Temps will recover to near normal during the latter half of the
holiday weekend. However there is some question as to where a
backdoor front will set up, and how efficiently that will focus
precip. Therefore will include a slight chance of showers and storms
from Saturday night onward.

&&

.Aviation (18Z TAF Issuance)...
Issued at 130 PM EDT Mon May 20 2013

Morning low-level debris clouds should give way to VFR conditions
this afternoon and evening as south-southwest winds help mix the
lower atmosphere and an upper-level ridge of high pressure holds
overhead. Expect a few Cu around 2-4 K feet and some upper level
clouds. Southerly winds will increase to between 10 and 15 mph by
late morning with a few gusts up around 20 mph. Scattered showers
and storms may move into southern Indiana late tonight, in a
weakening state. These appear to approach SDF in the pre-dawn hours.
Not sure what form they will possess, given the weakening. With low
confidence and differences between the latest suite of guidance,
will not mention in the SDF TAF at this time. Another concern is
marginal LLWS at SDF and BWG around 09-13Z. There is a decent
inversion at low levels, but if outflow moves in during this time,
LLWS will be void. Given the uncertainty and marginal status, will
not mention in the TAFs.

&&

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


Short Term.......MJP
Long Term........RAS
Aviation.........MJP

000
FXUS63 KLMK 201732
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
131 PM EDT MON MAY 20 2013

...Updated Aviation Discussion...

.Forecast Update...
Issued at 1100 AM EDT Mon May 20 2013

Low-level debris clouds from morning convection across the Middle
Mississippi Valley have overspread the Lower Ohio Valley. These
should break up a bit this afternoon as winds become gusty out of
the southwest and mix the boundary layer. Even with the cloud cover,
temperatures have increased into the low and mid 70s as of 10 AM
EDT. With clouds expected to break up later, will not make many
adjustments to the running forecast at this time.

Otherwise, ridging aloft remains in control. According to the latest
guidance and aircraft soundings, there is a cap aloft. Some models
break that cap this afternoon, while others hold on to at least some
weak inversion. Believe some models are advecting dewpoints that are
too high into the region, creating more available surface-based
CAPE. With this, will side with slightly lower dewpoints and at
least a weak cap. If bombarded with outflow boundaries today, then I
would say there is the potential for pulse storms to develop which
could go big with 2-3K J/kg available. However, outflow from morning
convection washed out before reaching our area and do not see any
convection close by that would help trigger development. So, plan to
continue with a dry forecast this afternoon, but will monitor trends.

&&

.Short Term (Now - Tuesday)...
Issued at 309 AM EDT May 20 2013

The biggest concern for the early morning hours continues to be
patchy fog formation, however steady southerly winds will likely
keep this potential confined to sheltered valleys and spots that
received rainfall yesterday. Will only keep patchy fog wording in
the zones for now. Otherwise expect a dry, mostly clear, and mild
overnight in the mid and upper 60s.

An upper level ridge axis is in place over the Ohio Valley and will
remain that way today. Meanwhile, central CONUS trough and its
associated features will continue to produce severe weather across
the eastern Plains into the Great Lakes. Will keep the forecast dry
over our region as there will be no real trigger for convection. A
couple of concerns worth noting, however. First of all, forecast
soundings do not show as much of a subsidence inversion as had been
forecast in past days. Secondly, the generally uncapped environment
will be quite unstable as temperatures in the upper 80s and dew
points in the upper 60s combine with steep low and mid level lapse
rates. There is potential that differential heating (from upstream
convective debris) or a remnant outflow boundary (also from upstream
convection) could set off a few thunderstorms. The higher resolution
20/00Z SPC WRF model shows this, but has not done well over our area
recently. Anything that is able to go in our environment will likely
go big due to the instability. After collaboration with surrounding
offices, have decided to keep the forecast dry as there is a low
probability of this occurring and coverage is expected to be less
than 20 percent. Will have to watch for areas of moisture
convergence and cu development this afternoon. If any storm does go,
large hail, cloud to ground lightning, and heavy rainfall would be
the main threats.

Temperatures are expected to be even warmer today under partly
cloudy skies and steady southerly flow. The forecast temperature for
Louisville (90) is expected to fall just 1 degree short of the old
record (91 set in 1934). A few spots will likely be right around the
90 degree mark, although the majority of locations will settle for
the upper 80s. Much will depend on cloud cover, especially if
upstream convective debris makes it this far east.

As we move into tonight and Tuesday, the upper level ridge over
our area will break down as the trough axis moves into the eastern
Plains and upper Midwest. With stronger westerlies aloft and a
strongly unstable airmass in place, upstream convection is expected
to survive into the Ohio Valley. Tonight`s chances will only be
across southern Indiana, however by Tuesday much of the CWA will
have solid storm chances (40-50%). This will begin an active period
of weather as the associated cold front hangs back to our west for a
couple of days. SPC has placed areas along and west of a Bowling
Green to Frankfort line in a slight risk. This makes sense given the
increase in 0-6 KM bulk shear around 25-30 knots and the strongly
unstable airmass. Multicell clusters with heavy rainfall and cloud
to ground lightning, along with isolated instances of large hail and
damaging winds will be the main threats.

Tonight`s temperatures will again be mild in the upper 60s and low
70s. Tuesday will see a warmup to the upper 80s in most spots.

.Long Term (Tuesday night - Sunday)...
Issued at 306 AM EDT Mon May 20 2013

Thunderstorms will erupt from Illinois to Texas around the beginning
of the long term and will push east into our region overnight
Tuesday night.  While severe weather looks likely out to our west,
the storms will become increasingly elevated as they head eastward
as shown on sounding progs advertising a strong nocturnal inversion
setting up around 925hPa.  So, while the low level jet does crank up
from Memphis to Indianapolis overnight, most of those winds should
stay off the surface.  Wet bulb zeroes look to be a little too high
for anything more than isolated marginally severe hail.  The best
chance for any strong storms will be along and west of Interstate 65.

Wednesday remains complicated.  Surface low pressure will move from
Illinois to Michigan and will drag a cold front into the Mississippi
Valley.  We`ll be under the entrance region of the upper jet and
additional convection is likely.  However, how strong the storms
will be is still a question mark.  Surface based instability may be
hampered depending on how much cloud and shower activity there is
from the previous night`s rain.  Total totals in the upper 40s and
SWEAT index around 300 are marginal for any severe storms (and are
actually lower on Wednesday than Tuesday night).  Wet bulb zeroes do
lower some on Wednesday, though, supporting a little more of a hail
risk.

Scattered storms will remain in the forecast Wednesday night and
Thursday until the aforementioned low pulls off into New England and
drags a secondary cold front through here Thursday evening.
Canadian high pressure will then move in from the north and keep us
dry through at least Saturday.

The forecast for Saturday night-Sunday is almost nil confidence,
with the GFS keeping us dry and the ECMWF bringing in widespread
shower/tstorm activity.  Will lean toward the generally more
reliable ECMWF this far out in the forecast, and even the drier GFS
has a warm front in the Ohio Valley during this time period, further
supporting the idea of a chance of rain.  Will keep PoPs very low.

Will go for high temperatures on Wednesday around 80, though the
prevalence of clouds/precip will have a big effect on that.  Highs
should then be in the 70s for the rest of the forecast period.

&&

.Aviation (18Z TAF Issuance)...
Issued at 130 PM EDT Mon May 20 2013

Morning low-level debris clouds should give way to VFR conditions
this afternoon and evening as south-southwest winds help mix the
lower atmosphere and an upper-level ridge of high pressure holds
overhead. Expect a few Cu around 2-4 K feet and some upper level
clouds. Southerly winds will increase to between 10 and 15 mph by
late morning with a few gusts up around 20 mph. Scattered showers
and storms may move into southern Indiana late tonight, in a
weakening state. These appear to approach SDF in the pre-dawn hours.
Not sure what form they will possess, given the weakening. With low
confidence and differences between the latest suite of guidance,
will not mention in the SDF TAF at this time. Another concern is
marginal LLWS at SDF and BWG around 09-13Z. There is a decent
inversion at low levels, but if outflow moves in during this time,
LLWS will be void. Given the uncertainty and marginal status, will
not mention in the TAFs.

&&

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


Update...........MJP
Short Term.......BJS
Long Term........13
Aviation.........MJP

000
FXUS63 KLMK 201501
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1101 AM EDT MON MAY 20 2013

.Forecast Update...
Issued at 1100 AM EDT Mon May 20 2013

Low-level debris clouds from morning convection across the Middle
Mississippi Valley have overspread the Lower Ohio Valley. These
should break up a bit this afternoon as winds become gusty out of
the southwest and mix the boundary layer. Even with the cloud cover,
temperatures have increased into the low and mid 70s as of 10 AM
EDT. With clouds expected to break up later, will not make many
adjustments to the running forecast at this time.

Otherwise, ridging aloft remains in control. According to the latest
guidance and aircraft soundings, there is a cap aloft. Some models
break that cap this afternoon, while others hold on to at least some
weak inversion. Believe some models are advecting dewpoints that are
too high into the region, creating more available surface-based
CAPE. With this, will side with slightly lower dewpoints and at
least a weak cap. If bombarded with outflow boundaries today, then I
would say there is the potential for pulse storms to develop which
could go big with 2-3K J/kg available. However, outflow from morning
convection washed out before reaching our area and do not see any
convection close by that would help trigger development. So, plan to
continue with a dry forecast this afternoon, but will monitor trends.

&&

.Short Term (Now - Tuesday)...
Issued at 309 AM EDT May 20 2013

The biggest concern for the early morning hours continues to be
patchy fog formation, however steady southerly winds will likely
keep this potential confined to sheltered valleys and spots that
received rainfall yesterday. Will only keep patchy fog wording in
the zones for now. Otherwise expect a dry, mostly clear, and mild
overnight in the mid and upper 60s.

An upper level ridge axis is in place over the Ohio Valley and will
remain that way today. Meanwhile, central CONUS trough and its
associated features will continue to produce severe weather across
the eastern Plains into the Great Lakes. Will keep the forecast dry
over our region as there will be no real trigger for convection. A
couple of concerns worth noting, however. First of all, forecast
soundings do not show as much of a subsidence inversion as had been
forecast in past days. Secondly, the generally uncapped environment
will be quite unstable as temperatures in the upper 80s and dew
points in the upper 60s combine with steep low and mid level lapse
rates. There is potential that differential heating (from upstream
convective debris) or a remnant outflow boundary (also from upstream
convection) could set off a few thunderstorms. The higher resolution
20/00Z SPC WRF model shows this, but has not done well over our area
recently. Anything that is able to go in our environment will likely
go big due to the instability. After collaboration with surrounding
offices, have decided to keep the forecast dry as there is a low
probability of this occurring and coverage is expected to be less
than 20 percent. Will have to watch for areas of moisture
convergence and cu development this afternoon. If any storm does go,
large hail, cloud to ground lightning, and heavy rainfall would be
the main threats.

Temperatures are expected to be even warmer today under partly
cloudy skies and steady southerly flow. The forecast temperature for
Louisville (90) is expected to fall just 1 degree short of the old
record (91 set in 1934). A few spots will likely be right around the
90 degree mark, although the majority of locations will settle for
the upper 80s. Much will depend on cloud cover, especially if
upstream convective debris makes it this far east.

As we move into tonight and Tuesday, the upper level ridge over
our area will break down as the trough axis moves into the eastern
Plains and upper Midwest. With stronger westerlies aloft and a
strongly unstable airmass in place, upstream convection is expected
to survive into the Ohio Valley. Tonight`s chances will only be
across southern Indiana, however by Tuesday much of the CWA will
have solid storm chances (40-50%). This will begin an active period
of weather as the associated cold front hangs back to our west for a
couple of days. SPC has placed areas along and west of a Bowling
Green to Frankfort line in a slight risk. This makes sense given the
increase in 0-6 KM bulk shear around 25-30 knots and the strongly
unstable airmass. Multicell clusters with heavy rainfall and cloud
to ground lightning, along with isolated instances of large hail and
damaging winds will be the main threats.

Tonight`s temperatures will again be mild in the upper 60s and low
70s. Tuesday will see a warmup to the upper 80s in most spots.

.Long Term (Tuesday night - Sunday)...
Issued at 306 AM EDT Mon May 20 2013

Thunderstorms will erupt from Illinois to Texas around the beginning
of the long term and will push east into our region overnight
Tuesday night.  While severe weather looks likely out to our west,
the storms will become increasingly elevated as they head eastward
as shown on sounding progs advertising a strong nocturnal inversion
setting up around 925hPa.  So, while the low level jet does crank up
from Memphis to Indianapolis overnight, most of those winds should
stay off the surface.  Wet bulb zeroes look to be a little too high
for anything more than isolated marginally severe hail.  The best
chance for any strong storms will be along and west of Interstate 65.

Wednesday remains complicated.  Surface low pressure will move from
Illinois to Michigan and will drag a cold front into the Mississippi
Valley.  We`ll be under the entrance region of the upper jet and
additional convection is likely.  However, how strong the storms
will be is still a question mark.  Surface based instability may be
hampered depending on how much cloud and shower activity there is
from the previous night`s rain.  Total totals in the upper 40s and
SWEAT index around 300 are marginal for any severe storms (and are
actually lower on Wednesday than Tuesday night).  Wet bulb zeroes do
lower some on Wednesday, though, supporting a little more of a hail
risk.

Scattered storms will remain in the forecast Wednesday night and
Thursday until the aforementioned low pulls off into New England and
drags a secondary cold front through here Thursday evening.
Canadian high pressure will then move in from the north and keep us
dry through at least Saturday.

The forecast for Saturday night-Sunday is almost nil confidence,
with the GFS keeping us dry and the ECMWF bringing in widespread
shower/tstorm activity.  Will lean toward the generally more
reliable ECMWF this far out in the forecast, and even the drier GFS
has a warm front in the Ohio Valley during this time period, further
supporting the idea of a chance of rain.  Will keep PoPs very low.

Will go for high temperatures on Wednesday around 80, though the
prevalence of clouds/precip will have a big effect on that.  Highs
should then be in the 70s for the rest of the forecast period.

&&

.Aviation (12Z TAF Issuance)...
Issued at 641 AM EDT Mon May 20 2013

There is still a small window for some briefly reduced visibilities
at BWG/LEX, however with the sun beginning to rise the window is
rapidly closing. Have removed mention from the TAFs. VFR conditions
will prevail today as an upper level ridge of high pressure holds
overhead. Expect a few Cu around 3-4 K feet and some upper level
clouds. Southerly winds will increase to between 10 and 15 mph by
late morning with occasional gusts up around 20 mph. Scattered
storms may move into southern Indiana by late evening, however will
stay north of SDF.

&&

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


Update...........MJP
Short Term.......BJS
Long Term........13
Aviation.........BJS

000
FXUS63 KLMK 201042
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
642 AM EDT MON MAY 20 2013

...Updated Aviation Discussion...

.Short Term (Now - Tuesday)...
Issued at 309 AM EDT May 20 2013

The biggest concern for the early morning hours continues to be
patchy fog formation, however steady southerly winds will likely
keep this potential confined to sheltered valleys and spots that
received rainfall yesterday. Will only keep patchy fog wording in
the zones for now. Otherwise expect a dry, mostly clear, and mild
overnight in the mid and upper 60s.

An upper level ridge axis is in place over the Ohio Valley and will
remain that way today. Meanwhile, central CONUS trough and its
associated features will continue to produce severe weather across
the eastern Plains into the Great Lakes. Will keep the forecast dry
over our region as there will be no real trigger for convection. A
couple of concerns worth noting, however. First of all, forecast
soundings do not show as much of a subsidence inversion as had been
forecast in past days. Secondly, the generally uncapped environment
will be quite unstable as temperatures in the upper 80s and dew
points in the upper 60s combine with steep low and mid level lapse
rates. There is potential that differential heating (from upstream
convective debris) or a remnant outflow boundary (also from upstream
convection) could set off a few thunderstorms. The higher resolution
20/00Z SPC WRF model shows this, but has not done well over our area
recently. Anything that is able to go in our environment will likely
go big due to the instability. After collaboration with surrounding
offices, have decided to keep the forecast dry as there is a low
probability of this occurring and coverage is expected to be less
than 20 percent. Will have to watch for areas of moisture
convergence and cu development this afternoon. If any storm does go,
large hail, cloud to ground lightning, and heavy rainfall would be
the main threats.

Temperatures are expected to be even warmer today under partly
cloudy skies and steady southerly flow. The forecast temperature for
Louisville (90) is expected to fall just 1 degree short of the old
record (91 set in 1934). A few spots will likely be right around the
90 degree mark, although the majority of locations will settle for
the upper 80s. Much will depend on cloud cover, especially if
upstream convective debris makes it this far east.

As we move into tonight and Tuesday, the upper level ridge over
our area will break down as the trough axis moves into the eastern
Plains and upper Midwest. With stronger westerlies aloft and a
strongly unstable airmass in place, upstream convection is expected
to survive into the Ohio Valley. Tonight`s chances will only be
across southern Indiana, however by Tuesday much of the CWA will
have solid storm chances (40-50%). This will begin an active period
of weather as the associated cold front hangs back to our west for a
couple of days. SPC has placed areas along and west of a Bowling
Green to Frankfort line in a slight risk. This makes sense given the
increase in 0-6 KM bulk shear around 25-30 knots and the strongly
unstable airmass. Multicell clusters with heavy rainfall and cloud
to ground lightning, along with isolated instances of large hail and
damaging winds will be the main threats.

Tonight`s temperatures will again be mild in the upper 60s and low
70s. Tuesday will see a warmup to the upper 80s in most spots.

.Long Term (Tuesday night - Sunday)...
Issued at 306 AM EDT Mon May 20 2013

Thunderstorms will erupt from Illinois to Texas around the beginning
of the long term and will push east into our region overnight
Tuesday night.  While severe weather looks likely out to our west,
the storms will become increasingly elevated as they head eastward
as shown on sounding progs advertising a strong nocturnal inversion
setting up around 925hPa.  So, while the low level jet does crank up
from Memphis to Indianapolis overnight, most of those winds should
stay off the surface.  Wet bulb zeroes look to be a little too high
for anything more than isolated marginally severe hail.  The best
chance for any strong storms will be along and west of Interstate 65.

Wednesday remains complicated.  Surface low pressure will move from
Illinois to Michigan and will drag a cold front into the Mississippi
Valley.  We`ll be under the entrance region of the upper jet and
additional convection is likely.  However, how strong the storms
will be is still a question mark.  Surface based instability may be
hampered depending on how much cloud and shower activity there is
from the previous night`s rain.  Total totals in the upper 40s and
SWEAT index around 300 are marginal for any severe storms (and are
actually lower on Wednesday than Tuesday night).  Wet bulb zeroes do
lower some on Wednesday, though, supporting a little more of a hail
risk.

Scattered storms will remain in the forecast Wednesday night and
Thursday until the aforementioned low pulls off into New England and
drags a secondary cold front through here Thursday evening.
Canadian high pressure will then move in from the north and keep us
dry through at least Saturday.

The forecast for Saturday night-Sunday is almost nil confidence,
with the GFS keeping us dry and the ECMWF bringing in widespread
shower/tstorm activity.  Will lean toward the generally more
reliable ECMWF this far out in the forecast, and even the drier GFS
has a warm front in the Ohio Valley during this time period, further
supporting the idea of a chance of rain.  Will keep PoPs very low.

Will go for high temperatures on Wednesday around 80, though the
prevalence of clouds/precip will have a big effect on that.  Highs
should then be in the 70s for the rest of the forecast period.

&&

.Aviation (12Z TAF Issuance)...
Issued at 641 AM EDT Mon May 20 2013

There is still a small window for some briefly reduced visibilities
at BWG/LEX, however with the sun beginning to rise the window is
rapidly closing. Have removed mention from the TAFs. VFR conditions
will prevail today as an upper level ridge of high pressure holds
overhead. Expect a few Cu around 3-4 K feet and some upper level
clouds. Southerly winds will increase to between 10 and 15 mph by
late morning with occasional gusts up around 20 mph. Scattered
storms may move into southern Indiana by late evening, however will
stay north of SDF.

&&

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


Short Term.......BJS
Long Term........13
Aviation.........BJS

000
FXUS63 KLMK 200710
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
310 AM EDT MON MAY 20 2013

.Short Term (Now - Tuesday)...
Issued at 309 AM EDT May 20 2013

The biggest concern for the early morning hours continues to be
patchy fog formation, however steady southerly winds will likely
keep this potential confined to sheltered valleys and spots that
received rainfall yesterday. Will only keep patchy fog wording in
the zones for now. Otherwise expect a dry, mostly clear, and mild
overnight in the mid and upper 60s.

An upper level ridge axis is in place of the Ohio Valley and will
remain that way today. Meanwhile, central CONUS trough and its
associated features will continue to produce severe weather across
the eastern Plains into the Great Lakes. Will keep the forecast dry
over our region as there will be no real trigger for convection. A
couple of concerns worth noting, however. First of all, forecast
soundings do not show as much of a subsidence inversion as had been
forecast in past days. Secondly, the generally uncapped environment
will be quite unstable as temperatures in the upper 80s and dew
points in the upper 60s combine with steep low and mid level lapse
rates. There is potential that differential heating (from upstream
convective debris) or a remnant outflow boundary (also from upstream
convection) could set off a few thunderstorms. The higher resolution
20/00Z SPC WRF model shows this, but has not done well over our area
recently. Anything that is able to go in our environment will likely
go big due to the instability. After collaboration with surrounding
offices, have decided to keep the forecast dry as there is a low
probability of this occurring and coverage is expected to be less
than 20 percent. Will have to watch for areas of moisture
convergence and cu development this afternoon. If any storm does go
large hail, cloud to ground lightning, and heavy rainfall would be
the main threats.

Temperatures are expected to be even warmer today under partly
cloudy skies and steady southerly flow. The forecast temperature for
Louisville (90) is expected to fall just 1 degree short of the old
record (91 set in 1934). A few spots will likely be right around the
90 degree mark, although the majority of locations will settle for
the upper 80s. Much will depend on cloud cover, especially if
upstream convective debris makes it this far east.

As we move into tonight and Tuesday, the upper level ridge over
our area will break down as the trough axis moves into the eastern
Plains and upper Midwest. With stronger westerlies aloft and a
strongly unstable airmass in place, upstream convection is expected
to survive into the Ohio Valley. Tonight`s chances will only be
across southern Indiana, however by Tuesday much of the CWA will
have solid storm chances (40-50%). This will begin an active period
of weather as the associated cold front hangs back to our west for a
couple of days. SPC has placed areas along and west of a Bowling
Green to Frankfort line in a slight risk. This makes sense given the
increase in 0-6 KM bulk shear around 25-30 knots and the strongly
unstable airmass. Multicell clusters with heavy rainfall and cloud
to ground lightning, along with isolated instances of large hail and
damaging winds will be the main threats.

Tonight`s temperatures will again be mild in the upper 60s and low
70s. Tuesday will see a warmup to the upper 80s in most spots.

.Long Term (Tuesday night - Sunday)...
Issued at 306 AM EDT Mon May 20 2013

Thunderstorms will erupt from Illinois to Texas around the beginning
of the long term and will push east into our region overnight
Tuesday night.  While severe weather looks likely out to our west,
the storms will become increasingly elevated as they head eastward
as shown on sounding progs advertising a strong nocturnal inversion
setting up around 925hPa.  So, while the low level jet does crank up
from Memphis to Indianapolis overnight, most of those winds should
stay off the surface.  Wet bulb zeroes look to be a little too high
for anything more than isolated marginally severe hail.  The best
chance for any strong storms will be along and west of Interstate 65.

Wednesday remains complicated.  Surface low pressure will move from
Illinois to Michigan and will drag a cold front into the Mississippi
Valley.  We`ll be under the entrance region of the upper jet and
additional convection is likely.  However, how strong the storms
will be is still a question mark.  Surface based instability may be
hampered depending on how much cloud and shower activity there is
from the previous night`s rain.  Total totals in the upper 40s and
SWEAT index around 300 are marginal for any severe storms (and are
actually lower on Wednesday than Tuesday night).  Wet bulb zeroes do
lower some on Wednesday, though, supporting a little more of a hail
risk.

Scattered storms will remain in the forecast Wednesday night and
Thursday until the aforementioned low pulls off into New England and
drags a secondary cold front through here Thursday evening.
Canadian high pressure will then move in from the north and keep us
dry through at least Saturday.

The forecast for Saturday night-Sunday is almost nil confidence,
with the GFS keeping us dry and the ECMWF bringing in widespread
shower/tstorm activity.  Will lean toward the generally more
reliable ECMWF this far out in the forecast, and even the drier GFS
has a warm front in the Ohio Valley during this time period, further
supporting the idea of a chance of rain.  Will keep PoPs very low.

Will go for high temperatures on Wednesday around 80, though the
prevalence of clouds/precip will have a big effect on that.  Highs
should then be in the 70s for the rest of the forecast period.

&&

.Aviation (06Z TAF Issuance)...
Issued at 1257 AM EDT Mon May 20 2013

Only concern for tonight will be for potential fog at BWG/LEX. With
dew points running in the upper 60s to around 70, lower atmosphere
is already moist. Mostly clear skies should help with radiational
cooling, although may be offset by steady southerly winds between 5
and 10 mph. Therefore, will not forecast visibilities to go as low
as they did last night, but will keep them in MVFR rangetoward dawn.
Otherwise, conditions improve shortly after sunrise with a more
robust southerly wind developing through the late morning into the
afternoon. Expect 10 to 15 mph with a few gusts up around 20 mph. A
mid level capping inversion should keep convection at bay, although
any very isolated storm that might develop would likely be strong.
Will not include any mention due to low probability of occurrence
and coverage.

&&

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


Short Term.......BJS
Long Term........13
Aviation.........BJS

000
FXUS63 KLMK 200458
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1257 AM EDT MON MAY 20 2013

...Updated Aviation Discussion...

.Forecast Update...
Issued at 900 PM EDT Sun May 19 2013

Updated the forecast mainly to remove showers/t-storms for the rest
of the night and add patchy fog.  Convective activity has diminished
over the area this evening and expect a dry night with upper level
ridging in place.

Added patchy fog to the forecast mainly in locations that received
rainfall today especially from Logan County to Hardin County to
Clark County in KY and points eastward which saw some
showers/t-storms this evening.  This area will also see the lightest
winds tonight although sfc winds should still be in the 4-5 kt range
from the south with winds aloft at h925 increasing to 20-25 kts
later in the night as a LLJ gets going.  Overall soundings don`t
show the greatest inversion tonight with the wind fields remaining
mixy, so have capped fog coverage at patchy and anticipate that
vsbys will generally be in the 1-4 mile range in any fog that
develops.  May need to keep an eye on localized dense fog overnight
in valley locations where it rained this evening, but overall don`t
see fog as a major hazard tonight.

&&

.Short Term (Now - Monday Night)...
Issued at 300 PM EDT Sun May 19 2013

The upper low is currently shifting east of eastern Kentucky while
an upper-level ridge axis builds over western and central portions
of the state. The subsidence inversion associated with the ridge
will act to shut down rain chances and shift the greatest potential
east. There are some isolated showers trying to form along the warm
front in western Kentucky, southeast Illinois, and southwest
Indiana, but these are capped by the ridge aloft, have limited
vertical extent, and should not last long. Otherwise, isolated to
scattered showers and thunderstorms will have the best potential
across south-central Kentucky and northeastward through the Kentucky
Blue Grass. These will dissipate this evening with loss of heating
and loss of forcing from outflow boundaries associated with previous
convection.

The upper ridge will hold over the area keeping things dry tonight.
Expect a light southerly flow, which should keep temps mild. Lows
should only drop into the mid and upper 60s. Light winds should also
keep down fog potential, particularly locally dense fog.

Upper ridge axis will continue to hold through the day Monday. We
will see no rain, but much warmer and humid conditions. As mentioned
in the previous discussion, H85 temps jump to around 18 C with only
partly cloudy skies and breezy south-southwest winds. Temperatures
should top out in the mid and upper 80s. Louisville, the heat
island, will make a run at 90 degrees, which will be close to the
record of 91 (1934). The ridge axis will begin to shift east Monday
night. Latest suite of guidance indicates convection that develops
across the Middle Mississippi Valley Monday afternoon and evening
will approach our northwestern CWA late Monday night. This should
approach in a weakening state with it arriving late at night, plus
the upper ridge will still have some influence on the area. Clouds
will increase through the night, which should hold lows in the mid
and upper 60s, with some locations around 70.

.Long Term (Tuesday - Sunday)...
Issued at 319 PM EDT Sun May 19 2013

Overall, not much change in the long term as the multi-model
consensus continue to show good run to run continuity.  Stacked
upper low over the southern Midwest is forecast to slowly drift
eastward into the southern Great Lakes before merging with a larger
upper level wave over SE Canada.  Associated surface cyclone is
forecast to move from the northern Plains and into the the Great
Lakes while dragging a surface cold front through the Ohio Valley.
The models have started to converge on a singular solution here with
the frontal boundary passing through Wednesday night...with a
secondary frontal boundary passing through on Thursday evening.

Before this system gets here, we`re going to see a generally
summertime pattern here in the Ohio Valley.  Fairly healthy high
pressure system over the western Atlantic working in tandem with the
low off to our northwest will result in continued southwesterly flow
into the Ohio Valley.  This will result in well above normal
temperatures at the beginning of the period along with increasingly
humid conditions.  Convection chances for Tuesday continue to look
more or less scattered at this point.  Still not seeing a well
defined lifting mechanism here other than differential heating and
convective overturning.  With deeper moisture and less capping over
the west/northwest sections, feel that convective coverage would
generally be more west of I-65 on Tuesday afternoon/evening.  Model
proximity soundings still suggest a high instability/low shear
profile suggestive of pulse type multi-cellular convection with a
threat of damaging winds and perhaps some hail.  Further east out
toward the I-75 corridor, a bit more capping is expected and thus
convective coverage looks to be less at this point.  High Tuesday
will warm into the mid-upper 80s with overnight lows in the upper
60s.

By Wednesday, surface cold front will be moving in closer from the
west.  Despite having a little stronger wind field coming into the
region along with better upper divergence, instability looks less on
Wednesday.  This is due to more mid-high level cloud cover expected
due to convective debris moving in from the west.  This would reduce
effective insolation during the afternoon.  Nonetheless, strong
storms will be possible given the overall profiles with damaging
winds and large hail being the primary severe weather threats.
Convection will likely continue into Wednesday night and Thursday as
we wait for the secondary front to push through along with the upper
trough.  So plan on keeping chance PoPs running through Thursday
night.  Highs Wednesday will be in the upper 70s to the mid 80s with
overnight lows in mid-upper 60s.

With the secondary front pushing through Thursday night, we`ll see
drier and cooler air push in late in the period.  The model
consensus has sped up the pattern progression here and it appears
that Friday and Saturday will remain dry and mild.  Highs Fri/Sat
look to top out in the 70-75 degree range with overnight lows in the
50s.

As usual for the later period, model differences start to emerge by
Sunday as some of the new data suggests that the cold front from
Thursday will stall out over the southern US and then retreat back
northward into the Ohio/Tennessee Valley.  This may serve as focus
for convective development as we head toward Memorial day.  For now,
will introduce some slight chc PoPs for Sunday, but if the latest
Euro trends continue, higher precipitation chances will be warranted
in future forecasts.

&&

.Aviation (06Z TAF Issuance)...
Issued at 1257 AM EDT Mon May 20 2013

Only concern for tonight will be for potential fog at BWG/LEX. With
dew points running in the upper 60s to around 70, lower atmosphere
is already moist. Mostly clear skies should help with radiational
cooling, although may be offset by steady southerly winds between 5
and 10 mph. Therefore, will not forecast visibilities to go as low
as they did last night, but will keep them in MVFR rangetoward dawn.
Otherwise, conditions improve shortly after sunrise with a more
robust southerly wind developing through the late morning into the
afternoon. Expect 10 to 15 mph with a few gusts up around 20 mph. A
mid level capping inversion should keep convection at bay, although
any very isolated storm that might develop would likely be strong.
Will not include any mention due to low probability of occurrence
and coverage.

&&

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


Update...........AMS
Short Term.......MJP
Long Term........MJ
Aviation.........BJS

000
FXUS63 KLMK 200104
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
903 PM EDT SUN MAY 19 2013

.Forecast Update...
Issued at 900 PM EDT Sun May 19 2013

Updated the forecast mainly to remove showers/t-storms for the rest
of the night and add patchy fog.  Convective activity has diminished
over the area this evening and expect a dry night with upper level
ridging in place.

Added patchy fog to the forecast mainly in locations that received
rainfall today especially from Logan County to Hardin County to
Clark County in KY and points eastward which saw some
showers/t-storms this evening.  This area will also see the lightest
winds tonight although sfc winds should still be in the 4-5 kt range
from the south with winds aloft at h925 increasing to 20-25 kts
later in the night as a LLJ gets going.  Overall soundings don`t
show the greatest inversion tonight with the wind fields remaining
mixy, so have capped fog coverage at patchy and anticipate that
vsbys will generally be in the 1-4 mile range in any fog that
develops.  May need to keep an eye on localized dense fog overnight
in valley locations where it rained this evening, but overall don`t
see fog as a major hazard tonight.

&&

.Short Term (Now - Monday Night)...
Issued at 300 PM EDT Sun May 19 2013

The upper low is currently shifting east of eastern Kentucky while
an upper-level ridge axis builds over western and central portions
of the state. The subsidence inversion associated with the ridge
will act to shut down rain chances and shift the greatest potential
east. There are some isolated showers trying to form along the warm
front in western Kentucky, southeast Illinois, and southwest
Indiana, but these are capped by the ridge aloft, have limited
vertical extent, and should not last long. Otherwise, isolated to
scattered showers and thunderstorms will have the best potential
across south-central Kentucky and northeastward through the Kentucky
Blue Grass. These will dissipate this evening with loss of heating
and loss of forcing from outflow boundaries associated with previous
convection.

The upper ridge will hold over the area keeping things dry tonight.
Expect a light southerly flow, which should keep temps mild. Lows
should only drop into the mid and upper 60s. Light winds should also
keep down fog potential, particularly locally dense fog.

Upper ridge axis will continue to hold through the day Monday. We
will see no rain, but much warmer and humid conditions. As mentioned
in the previous discussion, H85 temps jump to around 18 C with only
partly cloudy skies and breezy south-southwest winds. Temperatures
should top out in the mid and upper 80s. Louisville, the heat
island, will make a run at 90 degrees, which will be close to the
record of 91 (1934). The ridge axis will begin to shift east Monday
night. Latest suite of guidance indicates convection that develops
across the Middle Mississippi Valley Monday afternoon and evening
will approach our northwestern CWA late Monday night. This should
approach in a weakening state with it arriving late at night, plus
the upper ridge will still have some influence on the area. Clouds
will increase through the night, which should hold lows in the mid
and upper 60s, with some locations around 70.

.Long Term (Tuesday - Sunday)...
Issued at 319 PM EDT Sun May 19 2013

Overall, not much change in the long term as the multi-model
consensus continue to show good run to run continuity.  Stacked
upper low over the southern Midwest is forecast to slowly drift
eastward into the southern Great Lakes before merging with a larger
upper level wave over SE Canada.  Associated surface cyclone is
forecast to move from the northern Plains and into the the Great
Lakes while dragging a surface cold front through the Ohio Valley.
The models have started to converge on a singular solution here with
the frontal boundary passing through Wednesday night...with a
secondary frontal boundary passing through on Thursday evening.

Before this system gets here, we`re going to see a generally
summertime pattern here in the Ohio Valley.  Fairly healthy high
pressure system over the western Atlantic working in tandem with the
low off to our northwest will result in continued southwesterly flow
into the Ohio Valley.  This will result in well above normal
temperatures at the beginning of the period along with increasingly
humid conditions.  Convection chances for Tuesday continue to look
more or less scattered at this point.  Still not seeing a well
defined lifting mechanism here other than differential heating and
convective overturning.  With deeper moisture and less capping over
the west/northwest sections, feel that convective coverage would
generally be more west of I-65 on Tuesday afternoon/evening.  Model
proximity soundings still suggest a high instability/low shear
profile suggestive of pulse type multi-cellular convection with a
threat of damaging winds and perhaps some hail.  Further east out
toward the I-75 corridor, a bit more capping is expected and thus
convective coverage looks to be less at this point.  High Tuesday
will warm into the mid-upper 80s with overnight lows in the upper
60s.

By Wednesday, surface cold front will be moving in closer from the
west.  Despite having a little stronger wind field coming into the
region along with better upper divergence, instability looks less on
Wednesday.  This is due to more mid-high level cloud cover expected
due to convective debris moving in from the west.  This would reduce
effective insolation during the afternoon.  Nonetheless, strong
storms will be possible given the overall profiles with damaging
winds and large hail being the primary severe weather threats.
Convection will likely continue into Wednesday night and Thursday as
we wait for the secondary front to push through along with the upper
trough.  So plan on keeping chance PoPs running through Thursday
night.  Highs Wednesday will be in the upper 70s to the mid 80s with
overnight lows in mid-upper 60s.

With the secondary front pushing through Thursday night, we`ll see
drier and cooler air push in late in the period.  The model
consensus has sped up the pattern progression here and it appears
that Friday and Saturday will remain dry and mild.  Highs Fri/Sat
look to top out in the 70-75 degree range with overnight lows in the
50s.

As usual for the later period, model differences start to emerge by
Sunday as some of the new data suggests that the cold front from
Thursday will stall out over the southern US and then retreat back
northward into the Ohio/Tennessee Valley.  This may serve as focus
for convective development as we head toward Memorial day.  For now,
will introduce some slight chc PoPs for Sunday, but if the latest
Euro trends continue, higher precipitation chances will be warranted
in future forecasts.

&&

.Aviation (00Z TAF Issuance)...
Issued at 725 PM EDT Sun May 19 2013

VFR conditions expected for this TAF period as upper level ridging
moves through the area.  The only TAF concern will be the
possibility for some light br at LEX/BWG toward sunrise.  Not
totally confident that this will happen though given the mixy winds
aloft.  For consistency, will go ahead and leave a brief window for
MVFR vsbys at LEX/BWG tomorrow morning.  Once any light br clears,
SSW winds will pick up tomorrow afternoon as the sfc pressure
gradient tightens with winds gusting into the 17-20 kt range at
BWG/SDF.  LEX looks to be a little too far east to experience gusty
winds tomorrow afternoon although gradient winds should solidly
reach the 10-12 kt range with a few isld gusts possible.

&&

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


Update...........AMS
Short Term.......MJP
Long Term........MJ
Aviation.........AMS

000
FXUS63 KLMK 192327
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
726 PM EDT SUN MAY 19 2013

...Updated Aviation Discussion...

.Mesoscale Update...
Issued at 640 PM EDT Sun May 19 2013

After a few storms that produced quarter to golf ball size hail this
evening over central KY, storm strength is beginning to wane with
loss of day time heating and arrival of an upper ridge.  Expect
storms in the Bluegrass region to diminish over the next hour or two.

&&

.Short Term (Now - Monday Night)...
Issued at 300 PM EDT Sun May 19 2013

The upper low is currently shifting east of eastern Kentucky while
an upper-level ridge axis builds over western and central portions
of the state. The subsidence inversion associated with the ridge
will act to shut down rain chances and shift the greatest potential
east. There are some isolated showers trying to form along the warm
front in western Kentucky, southeast Illinois, and southwest
Indiana, but these are capped by the ridge aloft, have limited
vertical extent, and should not last long. Otherwise, isolated to
scattered showers and thunderstorms will have the best potential
across south-central Kentucky and northeastward through the Kentucky
Blue Grass. These will dissipate this evening with loss of heating
and loss of forcing from outflow boundaries associated with previous
convection.

The upper ridge will hold over the area keeping things dry tonight.
Expect a light southerly flow, which should keep temps mild. Lows
should only drop into the mid and upper 60s. Light winds should also
keep down fog potential, particularly locally dense fog.

Upper ridge axis will continue to hold through the day Monday. We
will see no rain, but much warmer and humid conditions. As mentioned
in the previous discussion, H85 temps jump to around 18 C with only
partly cloudy skies and breezy south-southwest winds. Temperatures
should top out in the mid and upper 80s. Louisville, the heat
island, will make a run at 90 degrees, which will be close to the
record of 91 (1934). The ridge axis will begin to shift east Monday
night. Latest suite of guidance indicates convection that develops
across the Middle Mississippi Valley Monday afternoon and evening
will approach our northwestern CWA late Monday night. This should
approach in a weakening state with it arriving late at night, plus
the upper ridge will still have some influence on the area. Clouds
will increase through the night, which should hold lows in the mid
and upper 60s, with some locations around 70.

.Long Term (Tuesday - Sunday)...
Issued at 319 PM EDT Sun May 19 2013

Overall, not much change in the long term as the multi-model
consensus continue to show good run to run continuity.  Stacked
upper low over the southern Midwest is forecast to slowly drift
eastward into the southern Great Lakes before merging with a larger
upper level wave over SE Canada.  Associated surface cyclone is
forecast to move from the northern Plains and into the the Great
Lakes while dragging a surface cold front through the Ohio Valley.
The models have started to converge on a singular solution here with
the frontal boundary passing through Wednesday night...with a
secondary frontal boundary passing through on Thursday evening.

Before this system gets here, we`re going to see a generally
summertime pattern here in the Ohio Valley.  Fairly healthy high
pressure system over the western Atlantic working in tandem with the
low off to our northwest will result in continued southwesterly flow
into the Ohio Valley.  This will result in well above normal
temperatures at the beginning of the period along with increasingly
humid conditions.  Convection chances for Tuesday continue to look
more or less scattered at this point.  Still not seeing a well
defined lifting mechanism here other than differential heating and
convective overturning.  With deeper moisture and less capping over
the west/northwest sections, feel that convective coverage would
generally be more west of I-65 on Tuesday afternoon/evening.  Model
proximity soundings still suggest a high instability/low shear
profile suggestive of pulse type multi-cellular convection with a
threat of damaging winds and perhaps some hail.  Further east out
toward the I-75 corridor, a bit more capping is expected and thus
convective coverage looks to be less at this point.  High Tuesday
will warm into the mid-upper 80s with overnight lows in the upper
60s.

By Wednesday, surface cold front will be moving in closer from the
west.  Despite having a little stronger wind field coming into the
region along with better upper divergence, instability looks less on
Wednesday.  This is due to more mid-high level cloud cover expected
due to convective debris moving in from the west.  This would reduce
effective insolation during the afternoon.  Nonetheless, strong
storms will be possible given the overall profiles with damaging
winds and large hail being the primary severe weather threats.
Convection will likely continue into Wednesday night and Thursday as
we wait for the secondary front to push through along with the upper
trough.  So plan on keeping chance PoPs running through Thursday
night.  Highs Wednesday will be in the upper 70s to the mid 80s with
overnight lows in mid-upper 60s.

With the secondary front pushing through Thursday night, we`ll see
drier and cooler air push in late in the period.  The model
consensus has sped up the pattern progression here and it appears
that Friday and Saturday will remain dry and mild.  Highs Fri/Sat
look to top out in the 70-75 degree range with overnight lows in the
50s.

As usual for the later period, model differences start to emerge by
Sunday as some of the new data suggests that the cold front from
Thursday will stall out over the southern US and then retreat back
northward into the Ohio/Tennessee Valley.  This may serve as focus
for convective development as we head toward Memorial day.  For now,
will introduce some slight chc PoPs for Sunday, but if the latest
Euro trends continue, higher precipitation chances will be warranted
in future forecasts.

&&

.Aviation (00Z TAF Issuance)...
Issued at 725 PM EDT Sun May 19 2013

VFR conditions expected for this TAF period as upper level ridging
moves through the area.  The only TAF concern will be the
possibility for some light br at LEX/BWG toward sunrise.  Not
totally confident that this will happen though given the mixy winds
aloft.  For consistency, will go ahead and leave a brief window for
MVFR vsbys at LEX/BWG tomorrow morning.  Once any light br clears,
SSW winds will pick up tomorrow afternoon as the sfc pressure
gradient tightens with winds gusting into the 17-20 kt range at
BWG/SDF.  LEX looks to be a little too far east to experience gusty
winds tomorrow afternoon although gradient winds should solidly
reach the 10-12 kt range with a few isld gusts possible.

&&

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

Mesoscale........AMS
Short Term.......MJP
Long Term........MJ
Aviation.........AMS

000
FXUS63 KLMK 192243
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
642 PM EDT SUN MAY 19 2013

.Mesoscale Update...
Issued at 640 PM EDT Sun May 19 2013

After a few storms that produced quarter to golf ball size hail this
evening over central KY, storm strength is beginning to wane with
loss of day time heating and arrival of an upper ridge.  Expect
storms in the Bluegrass region to diminish over the next hour or two.

&&

.Short Term (Now - Monday Night)...
Issued at 300 PM EDT Sun May 19 2013

The upper low is currently shifting east of eastern Kentucky while
an upper-level ridge axis builds over western and central portions
of the state. The subsidence inversion associated with the ridge
will act to shut down rain chances and shift the greatest potential
east. There are some isolated showers trying to form along the warm
front in western Kentucky, southeast Illinois, and southwest
Indiana, but these are capped by the ridge aloft, have limited
vertical extent, and should not last long. Otherwise, isolated to
scattered showers and thunderstorms will have the best potential
across south-central Kentucky and northeastward through the Kentucky
Blue Grass. These will dissipate this evening with loss of heating
and loss of forcing from outflow boundaries associated with previous
convection.

The upper ridge will hold over the area keeping things dry tonight.
Expect a light southerly flow, which should keep temps mild. Lows
should only drop into the mid and upper 60s. Light winds should also
keep down fog potential, particularly locally dense fog.

Upper ridge axis will continue to hold through the day Monday. We
will see no rain, but much warmer and humid conditions. As mentioned
in the previous discussion, H85 temps jump to around 18 C with only
partly cloudy skies and breezy south-southwest winds. Temperatures
should top out in the mid and upper 80s. Louisville, the heat
island, will make a run at 90 degrees, which will be close to the
record of 91 (1934). The ridge axis will begin to shift east Monday
night. Latest suite of guidance indicates convection that develops
across the Middle Mississippi Valley Monday afternoon and evening
will approach our northwestern CWA late Monday night. This should
approach in a weakening state with it arriving late at night, plus
the upper ridge will still have some influence on the area. Clouds
will increase through the night, which should hold lows in the mid
and upper 60s, with some locations around 70.

.Long Term (Tuesday - Sunday)...
Issued at 319 PM EDT Sun May 19 2013

Overall, not much change in the long term as the multi-model
consensus continue to show good run to run continuity.  Stacked
upper low over the southern Midwest is forecast to slowly drift
eastward into the southern Great Lakes before merging with a larger
upper level wave over SE Canada.  Associated surface cyclone is
forecast to move from the northern Plains and into the the Great
Lakes while dragging a surface cold front through the Ohio Valley.
The models have started to converge on a singular solution here with
the frontal boundary passing through Wednesday night...with a
secondary frontal boundary passing through on Thursday evening.

Before this system gets here, we`re going to see a generally
summertime pattern here in the Ohio Valley.  Fairly healthy high
pressure system over the western Atlantic working in tandem with the
low off to our northwest will result in continued southwesterly flow
into the Ohio Valley.  This will result in well above normal
temperatures at the beginning of the period along with increasingly
humid conditions.  Convection chances for Tuesday continue to look
more or less scattered at this point.  Still not seeing a well
defined lifting mechanism here other than differential heating and
convective overturning.  With deeper moisture and less capping over
the west/northwest sections, feel that convective coverage would
generally be more west of I-65 on Tuesday afternoon/evening.  Model
proximity soundings still suggest a high instability/low shear
profile suggestive of pulse type multi-cellular convection with a
threat of damaging winds and perhaps some hail.  Further east out
toward the I-75 corridor, a bit more capping is expected and thus
convective coverage looks to be less at this point.  High Tuesday
will warm into the mid-upper 80s with overnight lows in the upper
60s.

By Wednesday, surface cold front will be moving in closer from the
west.  Despite having a little stronger wind field coming into the
region along with better upper divergence, instability looks less on
Wednesday.  This is due to more mid-high level cloud cover expected
due to convective debris moving in from the west.  This would reduce
effective insolation during the afternoon.  Nonetheless, strong
storms will be possible given the overall profiles with damaging
winds and large hail being the primary severe weather threats.
Convection will likely continue into Wednesday night and Thursday as
we wait for the secondary front to push through along with the upper
trough.  So plan on keeping chance PoPs running through Thursday
night.  Highs Wednesday will be in the upper 70s to the mid 80s with
overnight lows in mid-upper 60s.

With the secondary front pushing through Thursday night, we`ll see
drier and cooler air push in late in the period.  The model
consensus has sped up the pattern progression here and it appears
that Friday and Saturday will remain dry and mild.  Highs Fri/Sat
look to top out in the 70-75 degree range with overnight lows in the
50s.

As usual for the later period, model differences start to emerge by
Sunday as some of the new data suggests that the cold front from
Thursday will stall out over the southern US and then retreat back
northward into the Ohio/Tennessee Valley.  This may serve as focus
for convective development as we head toward Memorial day.  For now,
will introduce some slight chc PoPs for Sunday, but if the latest
Euro trends continue, higher precipitation chances will be warranted
in future forecasts.

&&

.Aviation (18Z TAF Issuance)...
Issued at 125 PM EDT Sun May 19 2013

A weak upper low continues to meander around east Kentucky today,
with a weak frontal boundary across the Tennessee Valley. These two
disturbances will provide focus for isolated to scattered showers
and storms through the afternoon. Will continue with just scattered
shower coverage around LEX with isolated thunder. VFR conditions
will prevail through the afternoon and evening hours with a steady
SSW wind between 5 and 10 mph. Fog may become a concern again once
again tonight. However, surface winds are expected to stay up a bit,
which could limit fog, particularly dense fog, production.

&&

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


Mesoscale........AMS
Short Term.......MJP
Long Term........MJ
Aviation.........MJP

000
FXUS63 KLMK 191919
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
319 PM EDT SUN MAY 19 2013

.Short Term (Now - Monday Night)...
Issued at 300 PM EDT Sun May 19 2013

The upper low is currently shifting east of eastern Kentucky while
an upper-level ridge axis builds over western and central portions
of the state. The subsidence inversion associated with the ridge
will act to shut down rain chances and shift the greatest potential
east. There are some isolated showers trying to form along the warm
front in western Kentucky, southeast Illinois, and southwest
Indiana, but these are capped by the ridge aloft, have limited
vertical extent, and should not last long. Otherwise, isolated to
scattered showers and thunderstorms will have the best potential
across south-central Kentucky and northeastward through the Kentucky
Blue Grass. These will dissipate this evening with loss of heating
and loss of forcing from outflow boundaries associated with previous
convection.

The upper ridge will hold over the area keeping things dry tonight.
Expect a light southerly flow, which should keep temps mild. Lows
should only drop into the mid and upper 60s. Light winds should also
keep down fog potential, particularly locally dense fog.

Upper ridge axis will continue to hold through the day Monday. We
will see no rain, but much warmer and humid conditions. As mentioned
in the previous discussion, H85 temps jump to around 18 C with only
partly cloudy skies and breezy south-southwest winds. Temperatures
should top out in the mid and upper 80s. Louisville, the heat
island, will make a run at 90 degrees, which will be close to the
record of 91 (1934). The ridge axis will begin to shift east Monday
night. Latest suite of guidance indicates convection that develops
across the Middle Mississippi Valley Monday afternoon and evening
will approach our northwestern CWA late Monday night. This should
approach in a weakening state with it arriving late at night, plus
the upper ridge will still have some influence on the area. Clouds
will increase through the night, which should hold lows in the mid
and upper 60s, with some locations around 70.

.Long Term (Tuesday - Sunday)...
Issued at 319 PM EDT Sun May 19 2013

Overall, not much change in the long term as the multi-model
consensus continue to show good run to run continuity.  Stacked
upper low over the southern Midwest is forecast to slowly drift
eastward into the southern Great Lakes before merging with a larger
upper level wave over SE Canada.  Associated surface cyclone is
forecast to move from the northern Plains and into the the Great
Lakes while dragging a surface cold front through the Ohio Valley.
The models have started to converge on a singular solution here with
the frontal boundary passing through Wednesday night...with a
secondary frontal boundary passing through on Thursday evening.

Before this system gets here, we`re going to see a generally
summertime pattern here in the Ohio Valley.  Fairly healthy high
pressure system over the western Atlantic working in tandem with the
low off to our northwest will result in continued southwesterly flow
into the Ohio Valley.  This will result in well above normal
temperatures at the beginning of the period along with increasingly
humid conditions.  Convection chances for Tuesday continue to look
more or less scattered at this point.  Still not seeing a well
defined lifting mechanism here other than differential heating and
convective overturning.  With deeper moisture and less capping over
the west/northwest sections, feel that convective coverage would
generally be more west of I-65 on Tuesday afternoon/evening.  Model
proximity soundings still suggest a high instability/low shear
profile suggestive of pulse type multi-cellular convection with a
threat of damaging winds and perhaps some hail.  Further east out
toward the I-75 corridor, a bit more capping is expected and thus
convective coverage looks to be less at this point.  High Tuesday
will warm into the mid-upper 80s with overnight lows in the upper
60s.

By Wednesday, surface cold front will be moving in closer from the
west.  Despite having a little stronger wind field coming into the
region along with better upper divergence, instability looks less on
Wednesday.  This is due to more mid-high level cloud cover expected
due to convective debris moving in from the west.  This would reduce
effective insolation during the afternoon.  Nonetheless, strong
storms will be possible given the overall profiles with damaging
winds and large hail being the primary severe weather threats.
Convection will likely continue into Wednesday night and Thursday as
we wait for the secondary front to push through along with the upper
trough.  So plan on keeping chance PoPs running through Thursday
night.  Highs Wednesday will be in the upper 70s to the mid 80s with
overnight lows in mid-upper 60s.

With the secondary front pushing through Thursday night, we`ll see
drier and cooler air push in late in the period.  The model
consensus has sped up the pattern progression here and it appears
that Friday and Saturday will remain dry and mild.  Highs Fri/Sat
look to top out in the 70-75 degree range with overnight lows in the
50s.

As usual for the later period, model differences start to emerge by
Sunday as some of the new data suggests that the cold front from
Thursday will stall out over the southern US and then retreat back
northward into the Ohio/Tennessee Valley.  This may serve as focus
for convective development as we head toward Memorial day.  For now,
will introduce some slight chc PoPs for Sunday, but if the latest
Euro trends continue, higher precipitation chances will be warranted
in future forecasts.

&&

.Aviation (18Z TAF Issuance)...
Issued at 125 PM EDT Sun May 19 2013

A weak upper low continues to meander around east Kentucky today,
with a weak frontal boundary across the Tennessee Valley. These two
disturbances will provide focus for isolated to scattered showers
and storms through the afternoon. Will continue with just scattered
shower coverage around LEX with isolated thunder. VFR conditions
will prevail through the afternoon and evening hours with a steady
SSW wind between 5 and 10 mph. Fog may become a concern again once
again tonight. However, surface winds are expected to stay up a bit,
which could limit fog, particularly dense fog, production.

&&

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


Short Term.......MJP
Long Term........MJ
Aviation.........MJP

000
FXUS63 KLMK 191725
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
125 PM EDT SUN MAY 19 2013

...Updated Aviation Discussion...

.Forecast Update...
Issued at 1145 AM EDT Sun May 19 2013

Convection this morning across south-central Kentucky was on the
northern side of a weak warm frontal boundary. These storms produced
quite a bit of lightning, very heavy rain, and small hail. Activity
is diminishing with outflow moving in all directions away from the
old convective complex. Can see the outflow on radar and satellite
heading north toward the Ohio River. This may trigger new
development. However, an upper-level ridge axis and associated
capping is moving in from the west-northwest. This is evident in the
capping of cumulus across portions of western Kentucky. This will
continue to push east through the day. With this in mind, believe
the best chance for any additional isolated to scattered convection
will be across south-central Kentucky northeastward through the Blue
Grass, where capping aloft is less. Made a few adjustments to
near-term forecast to align with observations and blend with the
afternoon forecast, which looks on track.

&&

.Short Term (Now - Monday)...
Issued at 258 AM EDT Sun May 19 2013

The upper level low that has helped plague the area with scattered
showers and a few storms over the weekend is now located over SE
Kentucky. Meanwhile, a weak warm frontal boundary is situated from
central MO to central TN. This brings the boundary across western
Kentucky where some scattered to broken mid level clouds reside.
There are also some very light returns that are resulting in
sprinkles at best near the surface. Models have been depicting light
QPF with this boundary for several days, however think that even the
light QPF is overdone and may go with just some scattered sprinkles
through the morning hours across the southwest CWA, into the central
CWA. Otherwise, expect a dry morning. Will have to continue to
monitor fog development, with some locally dense spots possible. A
few obs have gone down to a half mile at times already. Do think
that the scattered to broken upper level clouds will hurt fog
potential some as we near dawn, so will only mention in the HWO
unless conditions warrant a more significant product.

The upper low is forecast to wobble over eastern Kentucky today
while an upper level ridge axis builds over central and western
portions of the state. A nice subsidence inversion looks to
accompany this ridge as evidenced on forecast soundings across the
western two thirds of the CWA by afternoon. Therefore, will only
keep iso-scattered (30%) pops in the eastern CWA this afternoon
where ridge does not build in until tonight. Will go dry across
western portions of the state as any potential precipitation with
the warm front should be shunted by the inversion. Will see partly
to mostly cloudy skies by afternoon as diurnally driven cu develop,
however will see a warm up. Look for low to mid 80s west and around
80 east.

Any lingering showers or storms will die off with the loss of
heating this evening. Upper ridge will hold over the area keeping
things dry. A light southerly flow will encompass the area which
should keep temps mild so only expecting lows in the mid and upper
60s. Also think the noticeable gradient winds will keep fog
formation potential in check.

Upper ridge axis will hold through the day on Monday as well,
continuing to keep the CWA dry. Will see a continued increase in
temperatures as H85 temps in jump up around 18 C with only partly
cloudy skies and steady SSW wind. Will go nearer the slightly cooler
NAM guidance in the mid and upper 80s. MAV guidance is going with
upper 80s and low 90s in many spots, but with the amount of
greenery, recent rainfall, and at least scattered cu, hard to
imagine we will get that warm. Just an interesting note, a high in
the low 90s at SDF on Monday would put the record of 91 (1934) in
jeopardy. Right now the forecast calls for 89. Stay tuned.

.Long Term (Monday night - Saturday)...
Issued at 257 AM EDT Sun May 19 2013

A stacked upper low over the mid-Missouri valley at the start of the
long term will slowly drift to the east to the Great Lakes by
Thursday morning and then get absorbed into a deep upper trof
sweeping through southeast Canada.  Correspondingly at the surface,
low pressure will advance from South Dakota to Michigan, pulling its
cold front through the Ohio Valley sometime Thursday or Thursday
evening.  Meanwhile, a large dome of high pressure over the Atlantic
will pump Gulf of Mexico warmth and moisture northward ahead of the
approaching storm system.  The result will be unseasonably
warm, muggy conditions with shower and thunderstorm chances.

Although the best chances for severe storms on Tuesday will remain
to our west, we could still see some strong pulsers here in the
afternoon or evening.  A few strong storms will again be possible on
Wednesday as the Plains system approaches.  Total totals and SWEAT
numbers are actually higher on Tuesday, likely due in part to
steeper mid level lapse rates.  Progged surface instability is also
stronger on Tuesday.  However on Wednesday there will be better
upper level divergence along with a 5H speed max and stronger 850hPa
winds as well.  Wednesday also should have higher 1000-850 RH, which
could serve as moisture to fuel storms but may also cause greater
cloud cover and, as a result, decreased insolation and less surface
based instability.

Canadian high pressure will invade from the north Friday/Saturday,
bringing much drier and cooler air to the region.

Tuesday will be the warmest day of the long term with afternoon
readings peaking in the middle and upper 80s.  Greater RH and shower
coverage on Wednesday should limit high temperatures to around 80.
Thursday through Saturday we`ll enjoy highs in the 70s.

&&

.Aviation (18Z TAF Issuance)...
Issued at 125 PM EDT Sun May 19 2013

A weak upper low continues to meander around east Kentucky today,
with a weak frontal boundary across the Tennessee Valley. These two
disturbances will provide focus for isolated to scattered showers
and storms through the afternoon. Will continue with just scattered
shower coverage around LEX with isolated thunder. VFR conditions
will prevail through the afternoon and evening hours with a steady
SSW wind between 5 and 10 mph. Fog may become a concern again once
again tonight. However, surface winds are expected to stay up a bit,
which could limit fog, particularly dense fog, production.

&&

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


Update...........MJP
Short Term.......BJS
Long Term........13
Aviation.........MJP

000
FXUS63 KLMK 191545
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1145 AM EDT SUN MAY 19 2013

.Forecast Update...
Issued at 1145 AM EDT Sun May 19 2013

Convection this morning across south-central Kentucky was on the
northern side of a weak warm frontal boundary. These storms produced
quite a bit of lightning, very heavy rain, and small hail. Activity
is diminishing with outflow moving in all directions away from the
old convective complex. Can see the outflow on radar and satellite
heading north toward the Ohio River. This may trigger new
development. However, an upper-level ridge axis and associated
capping is moving in from the west-northwest. This is evident in the
capping of cumulus across portions of western Kentucky. This will
continue to push east through the day. With this in mind, believe
the best chance for any additional isolated to scattered convection
will be across south-central Kentucky northeastward through the Blue
Grass, where capping aloft is less. Made a few adjustments to
near-term forecast to align with observations and blend with the
afternoon forecast, which looks on track.

&&

.Short Term (Now - Monday)...
Issued at 258 AM EDT Sun May 19 2013

The upper level low that has helped plague the area with scattered
showers and a few storms over the weekend is now located over SE
Kentucky. Meanwhile, a weak warm frontal boundary is situated from
central MO to central TN. This brings the boundary across western
Kentucky where some scattered to broken mid level clouds reside.
There are also some very light returns that are resulting in
sprinkles at best near the surface. Models have been depicting light
QPF with this boundary for several days, however think that even the
light QPF is overdone and may go with just some scattered sprinkles
through the morning hours across the southwest CWA, into the central
CWA. Otherwise, expect a dry morning. Will have to continue to
monitor fog development, with some locally dense spots possible. A
few obs have gone down to a half mile at times already. Do think
that the scattered to broken upper level clouds will hurt fog
potential some as we near dawn, so will only mention in the HWO
unless conditions warrant a more significant product.

The upper low is forecast to wobble over eastern Kentucky today
while an upper level ridge axis builds over central and western
portions of the state. A nice subsidence inversion looks to
accompany this ridge as evidenced on forecast soundings across the
western two thirds of the CWA by afternoon. Therefore, will only
keep iso-scattered (30%) pops in the eastern CWA this afternoon
where ridge does not build in until tonight. Will go dry across
western portions of the state as any potential precipitation with
the warm front should be shunted by the inversion. Will see partly
to mostly cloudy skies by afternoon as diurnally driven cu develop,
however will see a warm up. Look for low to mid 80s west and around
80 east.

Any lingering showers or storms will die off with the loss of
heating this evening. Upper ridge will hold over the area keeping
things dry. A light southerly flow will encompass the area which
should keep temps mild so only expecting lows in the mid and upper
60s. Also think the noticeable gradient winds will keep fog
formation potential in check.

Upper ridge axis will hold through the day on Monday as well,
continuing to keep the CWA dry. Will see a continued increase in
temperatures as H85 temps in jump up around 18 C with only partly
cloudy skies and steady SSW wind. Will go nearer the slightly cooler
NAM guidance in the mid and upper 80s. MAV guidance is going with
upper 80s and low 90s in many spots, but with the amount of
greenery, recent rainfall, and at least scattered cu, hard to
imagine we will get that warm. Just an interesting note, a high in
the low 90s at SDF on Monday would put the record of 91 (1934) in
jeopardy. Right now the forecast calls for 89. Stay tuned.

.Long Term (Monday night - Saturday)...
Issued at 257 AM EDT Sun May 19 2013

A stacked upper low over the mid-Missouri valley at the start of the
long term will slowly drift to the east to the Great Lakes by
Thursday morning and then get absorbed into a deep upper trof
sweeping through southeast Canada.  Correspondingly at the surface,
low pressure will advance from South Dakota to Michigan, pulling its
cold front through the Ohio Valley sometime Thursday or Thursday
evening.  Meanwhile, a large dome of high pressure over the Atlantic
will pump Gulf of Mexico warmth and moisture northward ahead of the
approaching storm system.  The result will be unseasonably
warm, muggy conditions with shower and thunderstorm chances.

Although the best chances for severe storms on Tuesday will remain
to our west, we could still see some strong pulsers here in the
afternoon or evening.  A few strong storms will again be possible on
Wednesday as the Plains system approaches.  Total totals and SWEAT
numbers are actually higher on Tuesday, likely due in part to
steeper mid level lapse rates.  Progged surface instability is also
stronger on Tuesday.  However on Wednesday there will be better
upper level divergence along with a 5H speed max and stronger 850hPa
winds as well.  Wednesday also should have higher 1000-850 RH, which
could serve as moisture to fuel storms but may also cause greater
cloud cover and, as a result, decreased insolation and less surface
based instability.

Canadian high pressure will invade from the north Friday/Saturday,
bringing much drier and cooler air to the region.

Tuesday will be the warmest day of the long term with afternoon
readings peaking in the middle and upper 80s.  Greater RH and shower
coverage on Wednesday should limit high temperatures to around 80.
Thursday through Saturday we`ll enjoy highs in the 70s.

&&

.Aviation (12Z TAF Issuance)...
Issued at 640 AM EDT Sun May 19 2013

Main concern this morning is with patches of dense fog. LEX will be
the terminal most impacted over next couple of hours as conditions
have dropped below minimums. Do expect improvement by around 9 AM
EDT. Enough mid level clouds have have developed around the BWG area
to improve conditions there. SDF should stay in the MVFR range,
although could briefly drop to IFR over the next hour or so.

Otherwise, a weak upper low will meander around east Kentucky today,
with a weak frontal boundary across the Tennessee Valley. These two
disturbances will provide focus for isolated to scattered showers
and storms today. At this point, confidence is only high enough in
scattered coverage around LEX to warrant mention. VFR conditions will
prevail from mid morning on with a steady SSW wind between 5 and 10
mph this afternoon. Fog may become a concern again tonight, although
surface winds are expected to stay up a bit and could limit fog
production.

&&

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


Update...........MJP
Short Term.......BJS
Long Term........13
Aviation.........BJS

000
FXUS63 KLMK 191041
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
640 AM EDT SUN MAY 19 2013

...Updated Aviation Discussion...

.Forecast Update...
Issued at 556 AM EDT Sun May 19 2013

A broken line of thunderstorms has blossomed over central Tennessee
this morning, however the bulk of the precipitation should remain
south of the state border. Do have mention of an isolated
thunderstorm possible along the southern tier or two of counties
this morning. Otherwise, the only other concern is with transient
patches of dense fog. Scattered mid low/mid level clouds are
limiting more widespread fog formation, however local obs and
webcams are showing enough patches to warrant a Special Weather
Statement. Visibilities may be reduced over short distances,
especially near bodies of water, sheltered valleys, and spots that
received recent rainfall. Conditions should improve by 9 AM EDT/8 AM
CDT.

&&

.Short Term (Now - Monday)...
Issued at 258 AM EDT Sun May 19 2013

The upper level low that has helped plague the area with scattered
showers and a few storms over the weekend is now located over SE
Kentucky. Meanwhile, a weak warm frontal boundary is situated from
central MO to central TN. This brings the boundary across western
Kentucky where some scattered to broken mid level clouds reside.
There are also some very light returns that are resulting in
sprinkles at best near the surface. Models have been depicting light
QPF with this boundary for several days, however think that even the
light QPF is overdone and may go with just some scattered sprinkles
through the morning hours across the southwest CWA, into the central
CWA. Otherwise, expect a dry morning. Will have to continue to
monitor fog development, with some locally dense spots possible. A
few obs have gone down to a half mile at times already. Do think
that the scattered to broken upper level clouds will hurt fog
potential some as we near dawn, so will only mention in the HWO
unless conditions warrant a more significant product.

The upper low is forecast to wobble over eastern Kentucky today
while an upper level ridge axis builds over central and western
portions of the state. A nice subsidence inversion looks to
accompany this ridge as evidenced on forecast soundings across the
western two thirds of the CWA by afternoon. Therefore, will only
keep iso-scattered (30%) pops in the eastern CWA this afternoon
where ridge does not build in until tonight. Will go dry across
western portions of the state as any potential precipitation with
the warm front should be shunted by the inversion. Will see partly
to mostly cloudy skies by afternoon as diurnally driven cu develop,
however will see a warm up. Look for low to mid 80s west and around
80 east.

Any lingering showers or storms will die off with the loss of
heating this evening. Upper ridge will hold over the area keeping
things dry. A light southerly flow will encompass the area which
should keep temps mild so only expecting lows in the mid and upper
60s. Also think the noticeable gradient winds will keep fog
formation potential in check.

Upper ridge axis will hold through the day on Monday as well,
continuing to keep the CWA dry. Will see a continued increase in
temperatures as H85 temps in jump up around 18 C with only partly
cloudy skies and steady SSW wind. Will go nearer the slightly cooler
NAM guidance in the mid and upper 80s. MAV guidance is going with
upper 80s and low 90s in many spots, but with the amount of
greenery, recent rainfall, and at least scattered cu, hard to
imagine we will get that warm. Just an interesting note, a high in
the low 90s at SDF on Monday would put the record of 91 (1934) in
jeopardy. Right now the forecast calls for 89. Stay tuned.

.Long Term (Monday night - Saturday)...
Issued at 257 AM EDT Sun May 19 2013

A stacked upper low over the mid-Missouri valley at the start of the
long term will slowly drift to the east to the Great Lakes by
Thursday morning and then get absorbed into a deep upper trof
sweeping through southeast Canada.  Correspondingly at the surface,
low pressure will advance from South Dakota to Michigan, pulling its
cold front through the Ohio Valley sometime Thursday or Thursday
evening.  Meanwhile, a large dome of high pressure over the Atlantic
will pump Gulf of Mexico warmth and moisture northward ahead of the
approaching storm system.  The result will be unseasonably
warm, muggy conditions with shower and thunderstorm chances.

Although the best chances for severe storms on Tuesday will remain
to our west, we could still see some strong pulsers here in the
afternoon or evening.  A few strong storms will again be possible on
Wednesday as the Plains system approaches.  Total totals and SWEAT
numbers are actually higher on Tuesday, likely due in part to
steeper mid level lapse rates.  Progged surface instability is also
stronger on Tuesday.  However on Wednesday there will be better
upper level divergence along with a 5H speed max and stronger 850hPa
winds as well.  Wednesday also should have higher 1000-850 RH, which
could serve as moisture to fuel storms but may also cause greater
cloud cover and, as a result, decreased insolation and less surface
based instability.

Canadian high pressure will invade from the north Friday/Saturday,
bringing much drier and cooler air to the region.

Tuesday will be the warmest day of the long term with afternoon
readings peaking in the middle and upper 80s.  Greater RH and shower
coverage on Wednesday should limit high temperatures to around 80.
Thursday through Saturday we`ll enjoy highs in the 70s.

&&

.Aviation (12Z TAF Issuance)...
Issued at 640 AM EDT Sun May 19 2013

Main concern this morning is with patches of dense fog. LEX will be
the terminal most impacted over next couple of hours as conditions
have dropped below minimums. Do expect improvement by around 9 AM
EDT. Enough mid level clouds have have developed around the BWG area
to improve conditions there. SDF should stay in the MVFR range,
although could briefly drop to IFR over the next hour or so.

Otherwise, a weak upper low will meander around east Kentucky today,
with a weak frontal boundary across the Tennessee Valley. These two
disturbances will provide focus for isolated to scattered showers
and storms today. At this point, confidence is only high enough in
scattered coverage around LEX to warrant mention. VFR conditions will
prevail from mid morning on with a steady SSW wind between 5 and 10
mph this afternoon. Fog may become a concern again tonight, although
surface winds are expected to stay up a bit and could limit fog
production.

&&

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


Update...........BJS
Short Term.......BJS
Long Term........13
Aviation.........BJS

000
FXUS63 KLMK 190957
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
557 AM EDT SUN MAY 19 2013

.Forecast Update...
Issued at 556 AM EDT Sun May 19 2013

A broken line of thunderstorms has blossomed over central Tennessee
this morning, however the bulk of the precipitation should remain
south of the state border. Do have mention of an isolated
thunderstorm possible along the southern tier or two of counties
this morning. Otherwise, the only other concern is with transient
patches of dense fog. Scattered mid low/mid level clouds are
limiting more widespread fog formation, however local obs and
webcams are showing enough patches to warrant a Special Weather
Statement. Visibilities may be reduced over short distances,
especially near bodies of water, sheltered valleys, and spots that
received recent rainfall. Conditions should improve by 9 AM EDT/8 AM
CDT.

&&

.Short Term (Now - Monday)...
Issued at 258 AM EDT Sun May 19 2013

The upper level low that has helped plague the area with scattered
showers and a few storms over the weekend is now located over SE
Kentucky. Meanwhile, a weak warm frontal boundary is situated from
central MO to central TN. This brings the boundary across western
Kentucky where some scattered to broken mid level clouds reside.
There are also some very light returns that are resulting in
sprinkles at best near the surface. Models have been depicting light
QPF with this boundary for several days, however think that even the
light QPF is overdone and may go with just some scattered sprinkles
through the morning hours across the southwest CWA, into the central
CWA. Otherwise, expect a dry morning. Will have to continue to
monitor fog development, with some locally dense spots possible. A
few obs have gone down to a half mile at times already. Do think
that the scattered to broken upper level clouds will hurt fog
potential some as we near dawn, so will only mention in the HWO
unless conditions warrant a more significant product.

The upper low is forecast to wobble over eastern Kentucky today
while an upper level ridge axis builds over central and western
portions of the state. A nice subsidence inversion looks to
accompany this ridge as evidenced on forecast soundings across the
western two thirds of the CWA by afternoon. Therefore, will only
keep iso-scattered (30%) pops in the eastern CWA this afternoon
where ridge does not build in until tonight. Will go dry across
western portions of the state as any potential precipitation with
the warm front should be shunted by the inversion. Will see partly
to mostly cloudy skies by afternoon as diurnally driven cu develop,
however will see a warm up. Look for low to mid 80s west and around
80 east.

Any lingering showers or storms will die off with the loss of
heating this evening. Upper ridge will hold over the area keeping
things dry. A light southerly flow will encompass the area which
should keep temps mild so only expecting lows in the mid and upper
60s. Also think the noticeable gradient winds will keep fog
formation potential in check.

Upper ridge axis will hold through the day on Monday as well,
continuing to keep the CWA dry. Will see a continued increase in
temperatures as H85 temps in jump up around 18 C with only partly
cloudy skies and steady SSW wind. Will go nearer the slightly cooler
NAM guidance in the mid and upper 80s. MAV guidance is going with
upper 80s and low 90s in many spots, but with the amount of
greenery, recent rainfall, and at least scattered cu, hard to
imagine we will get that warm. Just an interesting note, a high in
the low 90s at SDF on Monday would put the record of 91 (1934) in
jeopardy. Right now the forecast calls for 89. Stay tuned.

.Long Term (Monday night - Saturday)...
Issued at 257 AM EDT Sun May 19 2013

A stacked upper low over the mid-Missouri valley at the start of the
long term will slowly drift to the east to the Great Lakes by
Thursday morning and then get absorbed into a deep upper trof
sweeping through southeast Canada.  Correspondingly at the surface,
low pressure will advance from South Dakota to Michigan, pulling its
cold front through the Ohio Valley sometime Thursday or Thursday
evening.  Meanwhile, a large dome of high pressure over the Atlantic
will pump Gulf of Mexico warmth and moisture northward ahead of the
approaching storm system.  The result will be unseasonably
warm, muggy conditions with shower and thunderstorm chances.

Although the best chances for severe storms on Tuesday will remain
to our west, we could still see some strong pulsers here in the
afternoon or evening.  A few strong storms will again be possible on
Wednesday as the Plains system approaches.  Total totals and SWEAT
numbers are actually higher on Tuesday, likely due in part to
steeper mid level lapse rates.  Progged surface instability is also
stronger on Tuesday.  However on Wednesday there will be better
upper level divergence along with a 5H speed max and stronger 850hPa
winds as well.  Wednesday also should have higher 1000-850 RH, which
could serve as moisture to fuel storms but may also cause greater
cloud cover and, as a result, decreased insolation and less surface
based instability.

Canadian high pressure will invade from the north Friday/Saturday,
bringing much drier and cooler air to the region.

Tuesday will be the warmest day of the long term with afternoon
readings peaking in the middle and upper 80s.  Greater RH and shower
coverage on Wednesday should limit high temperatures to around 80.
Thursday through Saturday we`ll enjoy highs in the 70s.

&&

.Aviation (06Z TAF Issuance)...
Issued at 1255 AM EDT Sun May 19 2013

The upper low that has plagued the area with scattered showers is
now over SE Kentucky. Meanwhile, an upper level ridge axis is
centered over the Mississippi Valley and will progress eastward
toward the the TAF sites through the period. Will watch a weak
boundary stretched across the Tennessee Valley work northeastward
overnight, however only expect scattered to broken clouds around 3-5
K feet with the feature, and perhaps a few very light rain showers
near BWG. Impacts would be negligible. Of more concern, will be the
potential for fog under mostly clear skies and calm winds early on.
Will stick with a fairly low confidence forecast of MVFR
visibilities through dawn at BWG/LEX, before improvement. At this
point, thinking convection will be minimized at the TAF sites later
this afternoon as the upper level ridge axis moves overhead and mid
level cap keeps storms at bay. Will not mention any precipitation at
this point. Otherwise, expect scattered to broken VFR clouds with a
more noticeable SSW wind around 10 mph in the afternoon.

&&

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


Update...........BJS
Short Term.......BJS
Long Term........13
Aviation.........BJS

000
FXUS63 KLMK 190658
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
258 AM EDT SUN MAY 19 2013

.Short Term (Now - Monday)...
Issued at 258 AM EDT Sun May 19 2013

The upper level low that has helped plague the area with scattered
showers and a few storms over the weekend is now located over SE
Kentucky. Meanwhile, a weak warm frontal boundary is situated from
central MO to central TN. This brings the boundary across western
Kentucky where some scattered to broken mid level clouds reside.
There are also some very light returns that are resulting in
sprinkles at best near the surface. Models have been depicting light
QPF with this boundary for several days, however think that even the
light QPF is overdone and may go with just some scattered sprinkles
through the morning hours across the southwest CWA, into the central
CWA. Otherwise, expect a dry morning. Will have to continue to
monitor fog development, with some locally dense spots possible. A
few obs have gone down to a half mile at times already. Do think
that the scattered to broken upper level clouds will hurt fog
potential some as we near dawn, so will only mention in the HWO
unless conditions warrant a more significant product.

The upper low is forecast to wobble over eastern Kentucky today
while an upper level ridge axis builds over central and western
portions of the state. A nice subsidence inversion looks to accompany
this ridge as evidenced on forecast soundings across the western two
thirds of the CWA by afternoon. Therefore, will only keep
iso-scattered (30%) pops in the eastern CWA this afternoon where
ridge does not build in until tonight. Will go dry across western
portions of the state as any potential precipitation with the warm
front should be shunted by the inversion. Will see partly to mostly
cloudy skies by afternoon as diurnally driven cu develop, however
will see a warm up. Look for low to mid 80s west and around 80
east.

Any lingering showers or storms will die off with the loss of
heating this evening. Upper ridge will hold over the area keeping
things dry. A light southerly flow will encompass the area which
should keep temps mild so only expecting lows in the mid and upper
60s. Also think the noticeable gradient winds will keep fog
formation potential in check.

Upper ridge axis will hold through the day on Monday as well,
continuing to keep the CWA dry. Will see a continued increase in
temperatures as H85 temps in jump up around 18 C with only partly
cloudy skies and steady SSW wind. Will go nearer the slightly cooler
Nam guidance in the mid and upper 80s. Mav guidance is going with
upper 80s and low 90s in many spots, but with the amount of
greenery, recent rainfall, and at least scattered cu, hard to
imagine we will get that warm. Just an interesting note, a high in
the low 90s at SDF on Monday would put the record of 91 (1934) in
jeopardy. Right now the forecast calls for 89. Stay tuned.

.Long Term (Monday night - Saturday)...
Issued at 257 AM EDT Sun May 19 2013

A stacked upper low over the mid-Missouri valley at the start of the
long term will slowly drift to the east to the Great Lakes by
Thursday morning and then get absorbed into a deep upper trof
sweeping through southeast Canada.  Correspondingly at the surface,
low pressure will advance from South Dakota to Michigan, pulling its
cold front through the Ohio Valley sometime Thursday or Thursday
evening.  Meanwhile, a large dome of high pressure over the Atlantic
will pump Gulf of Mexico warmth and moisture northward ahead of the
approaching storm system.  The result will be unseasonably
warm, muggy conditions with shower and thunderstorm chances.

Although the best chances for severe storms on Tuesday will remain
to our west, we could still see some strong pulsers here in the
afternoon or evening.  A few strong storms will again be possible on
Wednesday as the Plains system approaches.  Total totals and SWEAT
numbers are actually higher on Tuesday, likely due in part to
steeper mid level lapse rates.  Progged surface instability is also
stronger on Tuesday.  However on Wednesday there will be better
upper level divergence along with a 5H speed max and stronger 850hPa
winds as well.  Wednesday also should have higher 1000-850 RH, which
could serve as moisture to fuel storms but may also cause greater
cloud cover and, as a result, decreased insolation and less surface
based instability.

Canadian high pressure will invade from the north Friday/Saturday,
bringing much drier and cooler air to the region.

Tuesday will be the warmest day of the long term with afternoon
readings peaking in the middle and upper 80s.  Greater RH and shower
coverage on Wednesday should limit high temperatures to around 80.
Thursday through Saturday we`ll enjoy highs in the 70s.

&&

.Aviation (06Z TAF Issuance)...
Issued at 1255 AM EDT Sun May 19 2013

The upper low that has plagued the area with scattered showers is
now over SE Kentucky. Meanwhile, an upper level ridge axis is
centered over the Mississippi Valley and will progress eastward
toward the the TAF sites through the period. Will watch a weak
boundary stretched across the Tennessee Valley work northeastward
overnight, however only expect scattered to broken clouds around 3-5
K feet with the feature, and perhaps a few very light rain showers
near BWG. Impacts would be negligible. Of more concern, will be the
potential for fog under mostly clear skies and calm winds early on.
Will stick with a fairly low confidence forecast of MVFR
visibilities through dawn at BWG/LEX, before improvement. At this
point, thinking convection will be minimized at the TAF sites later
this afternoon as the upper level ridge axis moves overhead and mid
level cap keeps storms at bay. Will not mention any precipitation at
this point. Otherwise, expect scattered to broken VFR clouds with a
more noticeable SSW wind around 10 mph in the afternoon.

&&

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


Short Term.......BJS
Long Term........13
Aviation.........BJS

000
FXUS63 KLMK 190457
AFDLMK
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
1257 AM EDT SUN MAY 19 2013

...Updated Aviation Discussion...

.Forecast Update...
Issued at 940 PM EDT Sat May 18 2013

Bumped up fog coverage in the grids, as airmass is pretty humid this
hour. Once sky cover breaks up we should quickly turn over to this
fog, with perhaps some low stratus as well. Winds are light out
there as the surface pressure gradients over the region is fairly
light now. Showers now are pretty isolated, so have lowered coverage
for the rest of the night.

&&

.Short Term (Now - Sunday Night)...
Issued at 300 PM EDT Sat May 18 2013

An area of low pressure continues to spin across the forecast area
this afternoon. Early morning light showers/drizzle gave way to a
few hours of dry conditions. However, now, with diurnal heating,
scattered showers have developed. Not seeing any lightning, but an
isolated thunderstorm cannot be ruled out given the steep lapse
rates aloft. Think the morning cloud cover helped keep instability
down a bit. The heavier rain producing showers should reside across
southeast Indiana and into the Kentucky Blue Grass, with isolated to
scattered showers elsewhere. Temperatures have reached the low to
mid 70s, with some warming still possible for several locations.

The coverage of showers and any storm that may develop will slowly
diminish this evening and tonight, as the upper low moves east. With
the departing low, an upper-level ridge axis will begin to build
across western Kentucky tonight. High resolution models continue to
indicate we will go briefly dry by around midnight through dawn.
Skies should become at least partly cloudy overnight, which will
allow temperatures to drop into the low and mid 60s and perhaps some
patchy fog or low stratus to form. Depending on the amount clearing,
some locally dense fog could develop, especially for locations that
receive rainfall today.

The upper low will move to the central Appalachians Sunday, with the
upper-level ridge axis continuing to build eastward. Expect diurnal
scattered convection across our eastern CWA, associated with the
upper low. Should also see some scattered convection across our
south and southwest with a weak warm front edging into the forecast
area. Heavy rain and of course lightning will be the main threats
with any convection that develops. High temperatures Sunday should
reach the upper 70s across the eastern CWA and low to mid 80s across
the west. Temperatures will drop back into the low and mid 60s under
partly cloudy skies. Once again, could see some patchy fog develop
around dawn Monday.

.Long Term (Monday - Saturday)...
Issued at 310 PM EDT Sat May 18 2013

The latest multi-model solutions continue to be in fairly good
agreement with a large upper level trough remaining nearly
stationary out over the Plains through the first part of the
forecast period.  With the upper trough to our west, the Ohio Valley
will see a relatively deep southwesterly flow aloft which will also
good moisture advection and continued warm temperatures through the
first half of the week.

Increasing humidity levels will be evident by Monday afternoon as
the southwesterly flow kicks into high gear.  Despite having good
moisture pooling across the region, latest model proximity soundings
do show expanding mid-level height rises across the region.  The
height rises along with a fairly evident capping inversion will
likely keep convection at a relative minimum Monday afternoon.
Highs Monday should top out in the 85-90 degree range.  With
dewpoints in the upper 60s to around 70, it will feel like the lower
90s across the region.  Lows Monday night look to cool into the
upper 60s to around 70.

By Tuesday, the upper ridge axis looks to shift a bit more to the
east.  Correspondingly, mid-level heights lower through the day and
the capping inversion is not as strong as what is indicated for
Monday.  As temperatures warm again into he 85-90 degree range,
we`re likely to see isolated to scattered convection develop during
the afternoon.  Latest data does not have a well defined lifting
mechanism that stands out...other than differential heating and
convective overturning.  Therefore, still am inclined to run low
chance PoPs equally across the forecast area.  Given the elevated
instability on Tuesday, a few of the storms that pop up could be on
the strong side.  The combination of high instability and weak shear
are suggestive of pulse type convection with damaging winds and hail
being a threat.

By midweek, the model solutions suggest that the upper trough axis
will slowly transition eastward from the Plains into the Great Lakes
region.  Corresponding occluding surface cyclone will move from the
Midwest into the Ohio Valley dragging a frontal boundary across the
region.  As this boundary pushes eastward, it will encounter ample
instability and moisture to produce a large area of thunderstorms
from the Great Lakes southward into the lower Mississippi Valley.
Strong to severe storms will be possible as this front moves
through.  Complex and unresolvable mesoscale interactions at this
time scale preclude defining a particular hazardous weather threat
at this time.  We feel those feature will come into clearer view
over the next few days.

The upper trough will slowly head eastward through the southern
Great Lakes on Thursday with a secondary frontal cruising through on
Thursday bringing yet another round of convection to the region.
Upper trough then looks to push on off to the east on Friday with
mid-level height rises taking place and surface high pressure
building back into the region. This should result in dry conditions
from Friday into Saturday.

Highs Wed/Thu will be cooler due to clouds and precipitation and
readings in the upper 70s to the lower 80s are expected with
overnight lows in the 60s.  Cooler temperatures look increasingly
likely on Friday/Saturday with highs in the lower 70s and overnight
lows cooling into the lower 50s.

&&

.Aviation (06Z TAF Issuance)...
Issued at 1255 AM EDT Sun May 19 2013

The upper low that has plagued the area with scattered showers is
now over SE Kentucky. Meanwhile, an upper level ridge axis is
centered over the Mississippi Valley and will progress eastward
toward the the TAF sites through the period. Will watch a weak
boundary stretched across the Tennessee Valley work northeastward
overnight, however only expect scattered to broken clouds around 3-5
K feet with the feature, and perhaps a few very light rain showers
near BWG. Impacts would be negligible. Of more concern, will be the
potential for fog under mostly clear skies and calm winds early on.
Will stick with a fairly low confidence forecast of MVFR
visibilities through dawn at BWG/LEX, before improvement. At this
point, thinking convection will be minimized at the TAF sites later
this afternoon as the upper level ridge axis moves overhead and mid
level cap keeps storms at bay. Will not mention any precipitation at
this point. Otherwise, expect scattered to broken VFR clouds with a
more noticeable SSW wind around 10 mph in the afternoon.

&&

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


Update...........RJS
Short Term.......MJP
Long Term........MJ
Aviation.........BJS