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000
FXUS63 KLSX 290801
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
301 AM CDT Tue Jul 29 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 259 AM CDT Tue Jul 29 2014

Instability sprinkles are possible this afternoon, but the
steepest lapse rates remain well to the north and east of the CWA.
High temperatures should be a few degrees warmer than yesterday
for most areas, but still 8-10 degrees below average for this time
of year.

Kanofsky

.LONG TERM:  (Tonight through Monday)
Issued at 259 AM CDT Tue Jul 29 2014

Previous forecast trends look reasonable and no major changes were
required with this forecast package. Ongoing northwest flow
pattern aloft will persist through the end of the week and into
the weekend. There are no strong signals for either widespread
precipitation or hot/humid weather during this time. Light
precip is possible each afternoon this week due to instability-
driven showers (possibly aided by transient vorticity maxima) and
perhaps a few thunderstorms, but most locations are expected to
remain dry. Moisture/instability parameters look a bit better on
Thu aftn compared to the rest of the week. The upper air pattern
begins to change over the weekend after a complex closed upper low
near Hudson Bay lifts northeastward and a ridge over the western
CONUS begins to shift into the plains.

Kanofsky

&&

.AVIATION:  (For the 06z TAFs through 06z Tuesday Night)
Issued at 1146 PM CDT Mon Jul 28 2014

Surface ridge to continue building into the region tonight with
light and variable winds and clear skies. There are still some
lingering mid clouds floating south through forecast area but they
should continue to dissipate. Otherwise, winds to pickup a bit by
mid morning from the northwest with some diurnal cu. Then winds
and clouds to diminish by sunset once again. Some models are
indicating a shortwave could undercut the ridge Tuesday afternoon
with some scattered showers possible. But confidence is low for
now, so kept tafs dry at this time.

Specifics for KSTL:
Surface ridge to continue building into the region tonight with
light and variable winds and clear skies. Otherwise, winds to
pickup a bit by 15z Tuesday from the northwest with some diurnal cu.
Then winds and clouds to diminish by sunset once again. Some
models are indicating a shortwave could undercut the ridge Tuesday
afternoon with some scattered showers possible. But confidence is
low for now, so kept taf dry at this time.

Byrd

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 290801
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
301 AM CDT Tue Jul 29 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 259 AM CDT Tue Jul 29 2014

Instability sprinkles are possible this afternoon, but the
steepest lapse rates remain well to the north and east of the CWA.
High temperatures should be a few degrees warmer than yesterday
for most areas, but still 8-10 degrees below average for this time
of year.

Kanofsky

.LONG TERM:  (Tonight through Monday)
Issued at 259 AM CDT Tue Jul 29 2014

Previous forecast trends look reasonable and no major changes were
required with this forecast package. Ongoing northwest flow
pattern aloft will persist through the end of the week and into
the weekend. There are no strong signals for either widespread
precipitation or hot/humid weather during this time. Light
precip is possible each afternoon this week due to instability-
driven showers (possibly aided by transient vorticity maxima) and
perhaps a few thunderstorms, but most locations are expected to
remain dry. Moisture/instability parameters look a bit better on
Thu aftn compared to the rest of the week. The upper air pattern
begins to change over the weekend after a complex closed upper low
near Hudson Bay lifts northeastward and a ridge over the western
CONUS begins to shift into the plains.

Kanofsky

&&

.AVIATION:  (For the 06z TAFs through 06z Tuesday Night)
Issued at 1146 PM CDT Mon Jul 28 2014

Surface ridge to continue building into the region tonight with
light and variable winds and clear skies. There are still some
lingering mid clouds floating south through forecast area but they
should continue to dissipate. Otherwise, winds to pickup a bit by
mid morning from the northwest with some diurnal cu. Then winds
and clouds to diminish by sunset once again. Some models are
indicating a shortwave could undercut the ridge Tuesday afternoon
with some scattered showers possible. But confidence is low for
now, so kept tafs dry at this time.

Specifics for KSTL:
Surface ridge to continue building into the region tonight with
light and variable winds and clear skies. Otherwise, winds to
pickup a bit by 15z Tuesday from the northwest with some diurnal cu.
Then winds and clouds to diminish by sunset once again. Some
models are indicating a shortwave could undercut the ridge Tuesday
afternoon with some scattered showers possible. But confidence is
low for now, so kept taf dry at this time.

Byrd

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 290446
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1146 PM CDT Mon Jul 28 2014

.UPDATE:
Issued at 950 PM CDT Mon Jul 28 2014

Much of the cloudcover from earlier this evening has dissipated
across the area, and temperatures have fallen to the mid 60s north
to low 70s south. Overnight lows in the mid 50s to around 60
degrees still look on target, and thus, no major changes have been
made to the forecast aside from minor adjustments to account for
near term trends.

JP
&&

.SHORT TERM:  (Through Late Tonight)
Issued at 325 PM CDT Mon Jul 28 2014

Sprawling ridge of high pressure extending from Saskatchewan Canada
southeast through the Great Plains and into the Midwest.  Extensive
area of diurnal stratocumulus has erupted again today, but this
should dissipate quickly this evening.  Expect a mostly clear night
with unseasonably cool temperatures from the mid 50s to around 60 in
the STL Metro area.

Carney

.LONG TERM:  (Tuesday through Next Monday)
Issued at 325 PM CDT Mon Jul 28 2014

A deep longwave upper TROF will dominate eastern North America thru
the end of the week, resulting in NW flow over our region.  Some
loosening up of this pattern looks to occur for early next week, but
the overall theme remains the same:  an extended period of below
normal temps should be the result with maxes from 80-85 each day
with mins in the 50s and low 60s.  Given how this July has not been
that hot at all, some of our climo sites, such as UIN and COU, could
be in line for a top 5 coolest July on record.

Weak upper level disturbances will trickle down in the NW flow the
next several days, and with marginal levels of moisture and some
favorable lo level instability, low-topped SHRA or even TSRA will be
possible in the afternoon the next couple of days.  See the activity
in northwest IA currently for reference.  It will be a very low PoP
though, with most not receiving anything.  By Thursday, a bit better
moisture but still not great, will allow somewhat deeper convection
to occur and this setup will continue thru the end of the week with
afternoon chances each day.  A drier setup looks set for next week
though.

TES
&&

.AVIATION:  (For the 06z TAFs through 06z Tuesday Night)
Issued at 1146 PM CDT Mon Jul 28 2014

Surface ridge to continue building into the region tonight with
light and variable winds and clear skies. There are still some
lingering mid clouds floating south through forecast area but they
should continue to dissipate. Otherwise, winds to pickup a bit by
mid morning from the northwest with some diurnal cu. Then winds
and clouds to diminish by sunset once again. Some models are
indicating a shortwave could undercut the ridge Tuesday afternoon
with some scattered showers possible. But confidence is low for
now, so kept tafs dry at this time.

Specifics for KSTL:
Surface ridge to continue building into the region tonight with
light and variable winds and clear skies. Otherwise, winds to
pickup a bit by 15z Tuesday from the northwest with some diurnal cu.
Then winds and clouds to diminish by sunset once again. Some
models are indicating a shortwave could undercut the ridge Tuesday
afternoon with some scattered showers possible. But confidence is
low for now, so kept taf dry at this time.

Byrd
&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$
WFO LSX







000
FXUS63 KLSX 290446
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1146 PM CDT Mon Jul 28 2014

.UPDATE:
Issued at 950 PM CDT Mon Jul 28 2014

Much of the cloudcover from earlier this evening has dissipated
across the area, and temperatures have fallen to the mid 60s north
to low 70s south. Overnight lows in the mid 50s to around 60
degrees still look on target, and thus, no major changes have been
made to the forecast aside from minor adjustments to account for
near term trends.

JP
&&

.SHORT TERM:  (Through Late Tonight)
Issued at 325 PM CDT Mon Jul 28 2014

Sprawling ridge of high pressure extending from Saskatchewan Canada
southeast through the Great Plains and into the Midwest.  Extensive
area of diurnal stratocumulus has erupted again today, but this
should dissipate quickly this evening.  Expect a mostly clear night
with unseasonably cool temperatures from the mid 50s to around 60 in
the STL Metro area.

Carney

.LONG TERM:  (Tuesday through Next Monday)
Issued at 325 PM CDT Mon Jul 28 2014

A deep longwave upper TROF will dominate eastern North America thru
the end of the week, resulting in NW flow over our region.  Some
loosening up of this pattern looks to occur for early next week, but
the overall theme remains the same:  an extended period of below
normal temps should be the result with maxes from 80-85 each day
with mins in the 50s and low 60s.  Given how this July has not been
that hot at all, some of our climo sites, such as UIN and COU, could
be in line for a top 5 coolest July on record.

Weak upper level disturbances will trickle down in the NW flow the
next several days, and with marginal levels of moisture and some
favorable lo level instability, low-topped SHRA or even TSRA will be
possible in the afternoon the next couple of days.  See the activity
in northwest IA currently for reference.  It will be a very low PoP
though, with most not receiving anything.  By Thursday, a bit better
moisture but still not great, will allow somewhat deeper convection
to occur and this setup will continue thru the end of the week with
afternoon chances each day.  A drier setup looks set for next week
though.

TES
&&

.AVIATION:  (For the 06z TAFs through 06z Tuesday Night)
Issued at 1146 PM CDT Mon Jul 28 2014

Surface ridge to continue building into the region tonight with
light and variable winds and clear skies. There are still some
lingering mid clouds floating south through forecast area but they
should continue to dissipate. Otherwise, winds to pickup a bit by
mid morning from the northwest with some diurnal cu. Then winds
and clouds to diminish by sunset once again. Some models are
indicating a shortwave could undercut the ridge Tuesday afternoon
with some scattered showers possible. But confidence is low for
now, so kept tafs dry at this time.

Specifics for KSTL:
Surface ridge to continue building into the region tonight with
light and variable winds and clear skies. Otherwise, winds to
pickup a bit by 15z Tuesday from the northwest with some diurnal cu.
Then winds and clouds to diminish by sunset once again. Some
models are indicating a shortwave could undercut the ridge Tuesday
afternoon with some scattered showers possible. But confidence is
low for now, so kept taf dry at this time.

Byrd
&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$
WFO LSX






000
FXUS63 KLSX 290253
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
953 PM CDT Mon Jul 28 2014

.UPDATE:
Issued at 950 PM CDT Mon Jul 28 2014

Much of the cloudcover from earlier this evening has dissipated
across the area, and temperatures have fallen to the mid 60s north
to low 70s south. Overnight lows in the mid 50s to around 60
degrees still look on target, and thus, no major changes have been
made to the forecast aside from minor adjustments to account for
near term trends.

JP

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 325 PM CDT Mon Jul 28 2014

Sprawling ridge of high pressure extending from Saskatchewan Canada
southeast through the Great Plains and into the Midwest.  Extensive
area of diurnal stratocumulus has erupted again today, but this
should dissipate quickly this evening.  Expect a mostly clear night
with unseasonably cool temperatures from the mid 50s to around 60 in
the STL Metro area.

Carney

.LONG TERM:  (Tuesday through Next Monday)
Issued at 325 PM CDT Mon Jul 28 2014

A deep longwave upper TROF will dominate eastern North America thru
the end of the week, resulting in NW flow over our region.  Some
loosening up of this pattern looks to occur for early next week, but
the overall theme remains the same:  an extended period of below
normal temps should be the result with maxes from 80-85 each day
with mins in the 50s and low 60s.  Given how this July has not been
that hot at all, some of our climo sites, such as UIN and COU, could
be in line for a top 5 coolest July on record.

Weak upper level disturbances will trickle down in the NW flow the
next several days, and with marginal levels of moisture and some
favorable lo level instability, low-topped SHRA or even TSRA will be
possible in the afternoon the next couple of days.  See the activity
in northwest IA currently for reference.  It will be a very low PoP
though, with most not receiving anything.  By Thursday, a bit better
moisture but still not great, will allow somewhat deeper convection
to occur and this setup will continue thru the end of the week with
afternoon chances each day.  A drier setup looks set for next week
though.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Tuesday Evening)
Issued at 643 PM CDT Mon Jul 28 2014

With surface ridge building in will see winds diminish this
evening. Also, diurnal sc continues to dissipate. So will see
clear skies and light and variable winds overnight. Then by mid
morning on Tuesday, winds to pickup a bit from the northwest with
some scattered cu developing.

Specifics for KSTL:
With surface ridge building in will see winds diminish this
evening. Also, diurnal sc continues to dissipate. So will see
clear skies and light and variable winds overnight. Then by mid
morning on Tuesday, winds to pickup a bit from the northwest with
some scattered cu developing.

Byrd

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 290253
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
953 PM CDT Mon Jul 28 2014

.UPDATE:
Issued at 950 PM CDT Mon Jul 28 2014

Much of the cloudcover from earlier this evening has dissipated
across the area, and temperatures have fallen to the mid 60s north
to low 70s south. Overnight lows in the mid 50s to around 60
degrees still look on target, and thus, no major changes have been
made to the forecast aside from minor adjustments to account for
near term trends.

JP

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 325 PM CDT Mon Jul 28 2014

Sprawling ridge of high pressure extending from Saskatchewan Canada
southeast through the Great Plains and into the Midwest.  Extensive
area of diurnal stratocumulus has erupted again today, but this
should dissipate quickly this evening.  Expect a mostly clear night
with unseasonably cool temperatures from the mid 50s to around 60 in
the STL Metro area.

Carney

.LONG TERM:  (Tuesday through Next Monday)
Issued at 325 PM CDT Mon Jul 28 2014

A deep longwave upper TROF will dominate eastern North America thru
the end of the week, resulting in NW flow over our region.  Some
loosening up of this pattern looks to occur for early next week, but
the overall theme remains the same:  an extended period of below
normal temps should be the result with maxes from 80-85 each day
with mins in the 50s and low 60s.  Given how this July has not been
that hot at all, some of our climo sites, such as UIN and COU, could
be in line for a top 5 coolest July on record.

Weak upper level disturbances will trickle down in the NW flow the
next several days, and with marginal levels of moisture and some
favorable lo level instability, low-topped SHRA or even TSRA will be
possible in the afternoon the next couple of days.  See the activity
in northwest IA currently for reference.  It will be a very low PoP
though, with most not receiving anything.  By Thursday, a bit better
moisture but still not great, will allow somewhat deeper convection
to occur and this setup will continue thru the end of the week with
afternoon chances each day.  A drier setup looks set for next week
though.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Tuesday Evening)
Issued at 643 PM CDT Mon Jul 28 2014

With surface ridge building in will see winds diminish this
evening. Also, diurnal sc continues to dissipate. So will see
clear skies and light and variable winds overnight. Then by mid
morning on Tuesday, winds to pickup a bit from the northwest with
some scattered cu developing.

Specifics for KSTL:
With surface ridge building in will see winds diminish this
evening. Also, diurnal sc continues to dissipate. So will see
clear skies and light and variable winds overnight. Then by mid
morning on Tuesday, winds to pickup a bit from the northwest with
some scattered cu developing.

Byrd

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 282347
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
647 PM CDT Mon Jul 28 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 325 PM CDT Mon Jul 28 2014

Sprawling ridge of high pressure extending from Saskatchewan Canada
southeast through the Great Plains and into the Midwest.  Extensive
area of diurnal stratocumulus has erupted again today, but this
should dissipate quickly this evening.  Expect a mostly clear night
with unseasonably cool temperatures from the mid 50s to around 60 in
the STL Metro area.

Carney

.LONG TERM:  (Tuesday through Next Monday)
Issued at 325 PM CDT Mon Jul 28 2014

A deep longwave upper TROF will dominate eastern North America thru
the end of the week, resulting in NW flow over our region.  Some
loosening up of this pattern looks to occur for early next week, but
the overall theme remains the same:  an extended period of below
normal temps should be the result with maxes from 80-85 each day
with mins in the 50s and low 60s.  Given how this July has not been
that hot at all, some of our climo sites, such as UIN and COU, could
be in line for a top 5 coolest July on record.

Weak upper level disturbances will trickle down in the NW flow the
next several days, and with marginal levels of moisture and some
favorable lo level instability, low-topped SHRA or even TSRA will be
possible in the afternoon the next couple of days.  See the activity
in northwest IA currently for reference.  It will be a very low PoP
though, with most not receiving anything.  By Thursday, a bit better
moisture but still not great, will allow somewhat deeper convection
to occur and this setup will continue thru the end of the week with
afternoon chances each day.  A drier setup looks set for next week
though.

TES
&&

.AVIATION:  (For the 00z TAFs through 00z Tuesday Evening)
Issued at 643 PM CDT Mon Jul 28 2014

With surface ridge building in will see winds diminish this
evening. Also, diurnal sc continues to dissipate. So will see
clear skies and light and variable winds overnight. Then by mid
morning on Tuesday, winds to pickup a bit from the northwest with
some scattered cu developing.

Specifics for KSTL:
With surface ridge building in will see winds diminish this
evening. Also, diurnal sc continues to dissipate. So will see
clear skies and light and variable winds overnight. Then by mid
morning on Tuesday, winds to pickup a bit from the northwest with
some scattered cu developing.

Byrd
&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$
WFO LSX






000
FXUS63 KLSX 282025
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
325 PM CDT Mon Jul 28 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 325 PM CDT Mon Jul 28 2014

Sprawling ridge of high pressure extending from Saskatchewan Canada
southeast through the Great Plains and into the Midwest.  Extensive
area of diurnal stratocumulus has erupted again today, but this
should dissipate quickly this evening.  Expect a mostly clear night
with unseasonably cool temperatures from the mid 50s to around 60 in
the STL Metro area.

Carney

.LONG TERM:  (Tuesday through Next Monday)
Issued at 325 PM CDT Mon Jul 28 2014

A deep longwave upper TROF will dominate eastern North America thru
the end of the week, resulting in NW flow over our region.  Some
loosening up of this pattern looks to occur for early next week, but
the overall theme remains the same:  an extended period of below
normal temps should be the result with maxes from 80-85 each day
with mins in the 50s and low 60s.  Given how this July has not been
that hot at all, some of our climo sites, such as UIN and COU, could
be in line for a top 5 coolest July on record.

Weak upper level disturbances will trickle down in the NW flow the
next several days, and with marginal levels of moisture and some
favorable lo level instability, low-topped SHRA or even TSRA will be
possible in the afternoon the next couple of days.  See the activity
in northwest IA currently for reference.  It will be a very low PoP
though, with most not receiving anything.  By Thursday, a bit better
moisture but still not great, will allow somewhat deeper convection
to occur and this setup will continue thru the end of the week with
afternoon chances each day.  A drier setup looks set for next week
though.

TES

&&

.AVIATION:  (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1206 PM CDT Mon Jul 28 2014

Hi pressure will control the weather through Tuesday. VFR flight
conditions and northwest flow will prevail. Expect this
afternoon`s ceilings to clear out by early this evening. Scattered
clouds will likely return Tuesday.

Specifics for KSTL:

VFR flight conditions and northwest flow is expected to continue
through Tuesday. Expect this afternoon`s ceilings to dissipate by
early evening.  Scattered clouds will likely return Tuesday.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX






000
FXUS63 KLSX 282025
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
325 PM CDT Mon Jul 28 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 325 PM CDT Mon Jul 28 2014

Sprawling ridge of high pressure extending from Saskatchewan Canada
southeast through the Great Plains and into the Midwest.  Extensive
area of diurnal stratocumulus has erupted again today, but this
should dissipate quickly this evening.  Expect a mostly clear night
with unseasonably cool temperatures from the mid 50s to around 60 in
the STL Metro area.

Carney

.LONG TERM:  (Tuesday through Next Monday)
Issued at 325 PM CDT Mon Jul 28 2014

A deep longwave upper TROF will dominate eastern North America thru
the end of the week, resulting in NW flow over our region.  Some
loosening up of this pattern looks to occur for early next week, but
the overall theme remains the same:  an extended period of below
normal temps should be the result with maxes from 80-85 each day
with mins in the 50s and low 60s.  Given how this July has not been
that hot at all, some of our climo sites, such as UIN and COU, could
be in line for a top 5 coolest July on record.

Weak upper level disturbances will trickle down in the NW flow the
next several days, and with marginal levels of moisture and some
favorable lo level instability, low-topped SHRA or even TSRA will be
possible in the afternoon the next couple of days.  See the activity
in northwest IA currently for reference.  It will be a very low PoP
though, with most not receiving anything.  By Thursday, a bit better
moisture but still not great, will allow somewhat deeper convection
to occur and this setup will continue thru the end of the week with
afternoon chances each day.  A drier setup looks set for next week
though.

TES

&&

.AVIATION:  (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1206 PM CDT Mon Jul 28 2014

Hi pressure will control the weather through Tuesday. VFR flight
conditions and northwest flow will prevail. Expect this
afternoon`s ceilings to clear out by early this evening. Scattered
clouds will likely return Tuesday.

Specifics for KSTL:

VFR flight conditions and northwest flow is expected to continue
through Tuesday. Expect this afternoon`s ceilings to dissipate by
early evening.  Scattered clouds will likely return Tuesday.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX





000
FXUS63 KLSX 281720
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1220 PM CDT Mon Jul 28 2014

.SHORT TERM: (Today and Tonight)
Issued at 300 AM CDT Mon Jul 28 2014

Surface high pressure currently centered in the northern Plains
will continue to settle southward through the Nation`s midsection
today bringing the first in a string of days of below average
temperatures. There should be a good blow-up of diurnal cu beginning
around mid-morning and dissipating by early evening. Baring some
persistent and unexpected patches of clouds overnight like those
currently across MN, most locations should fall into the 50s for
lows.

Glass

.LONG TERM: (Tuesday through Sunday)
Issued at 300 AM CDT Mon Jul 28 2014

The long wave trof over eastern NOAM will persist with varying degrees
of intensity through the end of the week and into the weekend ahead,
maintaining below average temperatures across the region. Surface
high pressure will continue to dominate on Tuesday although in a
weakening state. Cooling aloft could produce enough instability
for some spotty diurnal showers, however my confidence is not
great enough to mention in the forecast. The surface pressure
pattern during the later half of the week will largely be
dominated by weak high pressure although there could be subtle
wind shifts/pressure trofs passing southward associated with weak
disturbances in the NNW flow aloft. Any precipitation will be
quite spotty and mainly diurnally driven with probabilities too
low to mention, until Friday/Saturday when the odds are slightly
higher. The main baroclinic zone and threat of organized showers
and thunderstorms will remain well southwest/south of the CWA.

Glass

&&

.AVIATION:  (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1206 PM CDT Mon Jul 28 2014

Hi pressure will control the weather through Tuesday. VFR flight
conditions and northwest flow will prevail. Expect this
afternoon`s ceilings to clear out by early this evening. Scattered
clouds will likely return Tuesday.

Specifics for KSTL:

VFR flight conditions and northwest flow is expected to continue
through Tuesday. Expect this afternoon`s ceilings to dissipate by
early evening.  Scattered clouds will likely return Tuesday.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 281720
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1220 PM CDT Mon Jul 28 2014

.SHORT TERM: (Today and Tonight)
Issued at 300 AM CDT Mon Jul 28 2014

Surface high pressure currently centered in the northern Plains
will continue to settle southward through the Nation`s midsection
today bringing the first in a string of days of below average
temperatures. There should be a good blow-up of diurnal cu beginning
around mid-morning and dissipating by early evening. Baring some
persistent and unexpected patches of clouds overnight like those
currently across MN, most locations should fall into the 50s for
lows.

Glass

.LONG TERM: (Tuesday through Sunday)
Issued at 300 AM CDT Mon Jul 28 2014

The long wave trof over eastern NOAM will persist with varying degrees
of intensity through the end of the week and into the weekend ahead,
maintaining below average temperatures across the region. Surface
high pressure will continue to dominate on Tuesday although in a
weakening state. Cooling aloft could produce enough instability
for some spotty diurnal showers, however my confidence is not
great enough to mention in the forecast. The surface pressure
pattern during the later half of the week will largely be
dominated by weak high pressure although there could be subtle
wind shifts/pressure trofs passing southward associated with weak
disturbances in the NNW flow aloft. Any precipitation will be
quite spotty and mainly diurnally driven with probabilities too
low to mention, until Friday/Saturday when the odds are slightly
higher. The main baroclinic zone and threat of organized showers
and thunderstorms will remain well southwest/south of the CWA.

Glass

&&

.AVIATION:  (For the 18z TAFs through 18z Tuesday Afternoon)
Issued at 1206 PM CDT Mon Jul 28 2014

Hi pressure will control the weather through Tuesday. VFR flight
conditions and northwest flow will prevail. Expect this
afternoon`s ceilings to clear out by early this evening. Scattered
clouds will likely return Tuesday.

Specifics for KSTL:

VFR flight conditions and northwest flow is expected to continue
through Tuesday. Expect this afternoon`s ceilings to dissipate by
early evening.  Scattered clouds will likely return Tuesday.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 281122
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
622 AM CDT Mon Jul 28 2014

.SHORT TERM: (Today and Tonight)
Issued at 300 AM CDT Mon Jul 28 2014

Surface high pressure currently centered in the northern Plains
will continue to settle southward through the Nation`s midsection
today bringing the first in a string of days of below average
temperatures. There should be a good blow-up of diurnal cu beginning
around mid-morning and dissipating by early evening. Baring some
persistent and unexpected patches of clouds overnight like those
currently across MN, most locations should fall into the 50s for
lows.

Glass

.LONG TERM: (Tuesday through Sunday)
Issued at 300 AM CDT Mon Jul 28 2014

The long wave trof over eastern NOAM will persist with varying degrees
of intensity through the end of the week and into the weekend ahead,
maintaining below average temperatures across the region. Surface
high pressure will continue to dominate on Tuesday although in a
weakening state. Cooling aloft could produce enough instability
for some spotty diurnal showers, however my confidence is not
great enough to mention in the forecast. The surface pressure
pattern during the later half of the week will largely be
dominated by weak high pressure although there could be subtle
wind shifts/pressure trofs passing southward associated with weak
disturbances in the NNW flow aloft. Any precipitation will be
quite spotty and mainly diurnally driven with probabilities too
low to mention, until Friday/Saturday when the odds are slightly
higher. The main baroclinic zone and threat of organized showers
and thunderstorms will remain well southwest/south of the CWA.

Glass

&&

.AVIATION:  (For the 12z TAFs through 12z Tuesday Morning)
Issued at 619 AM CDT Mon Jul 28 2014

VFR with diurnal cu developing this morning and scattering out by
late afternoon. Bufkit profiles support wind gusts of 15-20kts.

Specifics for KSTL: VFR with diurnal cu developing this morning
and scattering out by late afternoon. Bufkit profiles support wind
gusts of 15-20kts.

Kanofsky

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 281122
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
622 AM CDT Mon Jul 28 2014

.SHORT TERM: (Today and Tonight)
Issued at 300 AM CDT Mon Jul 28 2014

Surface high pressure currently centered in the northern Plains
will continue to settle southward through the Nation`s midsection
today bringing the first in a string of days of below average
temperatures. There should be a good blow-up of diurnal cu beginning
around mid-morning and dissipating by early evening. Baring some
persistent and unexpected patches of clouds overnight like those
currently across MN, most locations should fall into the 50s for
lows.

Glass

.LONG TERM: (Tuesday through Sunday)
Issued at 300 AM CDT Mon Jul 28 2014

The long wave trof over eastern NOAM will persist with varying degrees
of intensity through the end of the week and into the weekend ahead,
maintaining below average temperatures across the region. Surface
high pressure will continue to dominate on Tuesday although in a
weakening state. Cooling aloft could produce enough instability
for some spotty diurnal showers, however my confidence is not
great enough to mention in the forecast. The surface pressure
pattern during the later half of the week will largely be
dominated by weak high pressure although there could be subtle
wind shifts/pressure trofs passing southward associated with weak
disturbances in the NNW flow aloft. Any precipitation will be
quite spotty and mainly diurnally driven with probabilities too
low to mention, until Friday/Saturday when the odds are slightly
higher. The main baroclinic zone and threat of organized showers
and thunderstorms will remain well southwest/south of the CWA.

Glass

&&

.AVIATION:  (For the 12z TAFs through 12z Tuesday Morning)
Issued at 619 AM CDT Mon Jul 28 2014

VFR with diurnal cu developing this morning and scattering out by
late afternoon. Bufkit profiles support wind gusts of 15-20kts.

Specifics for KSTL: VFR with diurnal cu developing this morning
and scattering out by late afternoon. Bufkit profiles support wind
gusts of 15-20kts.

Kanofsky

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 280816
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
316 AM CDT Mon Jul 28 2014

.SHORT TERM: (Today and Tonight)
Issued at 300 AM CDT Mon Jul 28 2014

Surface high pressure currently centered in the northern Plains
will continue to settle southward through the Nation`s midsection
today bringing the first in a string of days of below average
temperatures. There should be a good blow-up of diurnal cu beginning
around mid-morning and dissipating by early evening. Baring some
persistent and unexpected patches of clouds overnight like those
currently across MN, most locations should fall into the 50s for
lows.

Glass

.LONG TERM: (Tuesday through Sunday)
Issued at 300 AM CDT Mon Jul 28 2014

The long wave trof over eastern NOAM will persist with varying degrees
of intensity through the end of the week and into the weekend ahead,
maintaining below average temperatures across the region. Surface
high pressure will continue to dominate on Tuesday although in a
weakening state. Cooling aloft could produce enough instability
for some spotty diurnal showers, however my confidence is not
great enough to mention in the forecast. The surface pressure
pattern during the later half of the week will largely be
dominated by weak high pressure although there could be subtle
wind shifts/pressure trofs passing southward associated with weak
disturbances in the NNW flow aloft. Any precipitation will be
quite spotty and mainly diurnally driven with probabilities too
low to mention, until Friday/Saturday when the odds are slightly
higher. The main baroclinic zone and threat of organized showers
and thunderstorms will remain well southwest/south of the CWA.

Glass

&&

.AVIATION:  (For the 06z TAFs through 06z Monday Night)
Issued at 1128 PM CDT Sun Jul 27 2014

Northwest winds near or below 10KT tonight will increase and become
gusty once again by mid- morning on Monday, but not quite as gusty
as on Sunday afternoon. Through the day, winds will slowly veer
to a more northerly direction before becoming light
northerly/light and variable overnight Monday night. Expect
diurnal cumulus to return on Monday as well, and while most
locations should see scattered coverage, models indicate several
hours of broken ceilings Monday morning through early Monday
afternoon that could affect metro area TAF sites. However,
ceilings will be around 5000ft, thus, VFR flight conditions will
prevail through the period.

Specifics for KSTL:
Light northwest winds tonight will increase and gust to around
18KT by late morning on Monday. Expect diurnal cumulus to develop
by around 15Z, and with cooler air aloft and models indicating
steepening lapse rates, broken ceilings are expected for at least
several hours from late Monday morning through Monday afternoon.
However, cloudcover should scatter out by late afternoon and then
clear, with winds becoming light northerly overnight. VFR through
the period.

JP

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 280816
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
316 AM CDT Mon Jul 28 2014

.SHORT TERM: (Today and Tonight)
Issued at 300 AM CDT Mon Jul 28 2014

Surface high pressure currently centered in the northern Plains
will continue to settle southward through the Nation`s midsection
today bringing the first in a string of days of below average
temperatures. There should be a good blow-up of diurnal cu beginning
around mid-morning and dissipating by early evening. Baring some
persistent and unexpected patches of clouds overnight like those
currently across MN, most locations should fall into the 50s for
lows.

Glass

.LONG TERM: (Tuesday through Sunday)
Issued at 300 AM CDT Mon Jul 28 2014

The long wave trof over eastern NOAM will persist with varying degrees
of intensity through the end of the week and into the weekend ahead,
maintaining below average temperatures across the region. Surface
high pressure will continue to dominate on Tuesday although in a
weakening state. Cooling aloft could produce enough instability
for some spotty diurnal showers, however my confidence is not
great enough to mention in the forecast. The surface pressure
pattern during the later half of the week will largely be
dominated by weak high pressure although there could be subtle
wind shifts/pressure trofs passing southward associated with weak
disturbances in the NNW flow aloft. Any precipitation will be
quite spotty and mainly diurnally driven with probabilities too
low to mention, until Friday/Saturday when the odds are slightly
higher. The main baroclinic zone and threat of organized showers
and thunderstorms will remain well southwest/south of the CWA.

Glass

&&

.AVIATION:  (For the 06z TAFs through 06z Monday Night)
Issued at 1128 PM CDT Sun Jul 27 2014

Northwest winds near or below 10KT tonight will increase and become
gusty once again by mid- morning on Monday, but not quite as gusty
as on Sunday afternoon. Through the day, winds will slowly veer
to a more northerly direction before becoming light
northerly/light and variable overnight Monday night. Expect
diurnal cumulus to return on Monday as well, and while most
locations should see scattered coverage, models indicate several
hours of broken ceilings Monday morning through early Monday
afternoon that could affect metro area TAF sites. However,
ceilings will be around 5000ft, thus, VFR flight conditions will
prevail through the period.

Specifics for KSTL:
Light northwest winds tonight will increase and gust to around
18KT by late morning on Monday. Expect diurnal cumulus to develop
by around 15Z, and with cooler air aloft and models indicating
steepening lapse rates, broken ceilings are expected for at least
several hours from late Monday morning through Monday afternoon.
However, cloudcover should scatter out by late afternoon and then
clear, with winds becoming light northerly overnight. VFR through
the period.

JP

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 280439
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1139 PM CDT Sun Jul 27 2014

.UPDATE:
Issued at 851 PM CDT Sun Jul 27 2014
Issued at 558 PM CDT Sun Jul 27 2014

Just made some minor changes to the temperature and wind
forecasts. otherwise going forecast look good. We can really use
some rain around here.

Przybylinski

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 06z TAFs through 06z Monday Night)
Issued at 1128 PM CDT Sun Jul 27 2014

Northwest winds near or below 10KT tonight will increase and become
gusty once again by mid- morning on Monday, but not quite as gusty
as on Sunday afternoon. Through the day, winds will slowly veer
to a more northerly direction before becoming light
northerly/light and variable overnight Monday night. Expect
diurnal cumulus to return on Monday as well, and while most
locations should see scattered coverage, models indicate several
hours of broken ceilings Monday morning through early Monday
afternoon that could affect metro area TAF sites. However,
ceilings will be around 5000ft, thus, VFR flight conditions will
prevail through the period.

Specifics for KSTL:
Light northwest winds tonight will increase and gust to around
18KT by late morning on Monday. Expect diurnal cumulus to develop
by around 15Z, and with cooler air aloft and models indicating
steepening lapse rates, broken ceilings are expected for at least
several hours from late Monday morning through Monday afternoon.
However, cloudcover should scatter out by late afternoon and then
clear, with winds becoming light northerly overnight. VFR through
the period.

JP

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 280439
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1139 PM CDT Sun Jul 27 2014

.UPDATE:
Issued at 851 PM CDT Sun Jul 27 2014
Issued at 558 PM CDT Sun Jul 27 2014

Just made some minor changes to the temperature and wind
forecasts. otherwise going forecast look good. We can really use
some rain around here.

Przybylinski

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 06z TAFs through 06z Monday Night)
Issued at 1128 PM CDT Sun Jul 27 2014

Northwest winds near or below 10KT tonight will increase and become
gusty once again by mid- morning on Monday, but not quite as gusty
as on Sunday afternoon. Through the day, winds will slowly veer
to a more northerly direction before becoming light
northerly/light and variable overnight Monday night. Expect
diurnal cumulus to return on Monday as well, and while most
locations should see scattered coverage, models indicate several
hours of broken ceilings Monday morning through early Monday
afternoon that could affect metro area TAF sites. However,
ceilings will be around 5000ft, thus, VFR flight conditions will
prevail through the period.

Specifics for KSTL:
Light northwest winds tonight will increase and gust to around
18KT by late morning on Monday. Expect diurnal cumulus to develop
by around 15Z, and with cooler air aloft and models indicating
steepening lapse rates, broken ceilings are expected for at least
several hours from late Monday morning through Monday afternoon.
However, cloudcover should scatter out by late afternoon and then
clear, with winds becoming light northerly overnight. VFR through
the period.

JP

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 280154
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
854 PM CDT Sun Jul 27 2014

.UPDATE:
Issued at 851 PM CDT Sun Jul 27 2014
Issued at 558 PM CDT Sun Jul 27 2014

Just made some minor changes to the temperature and wind
forecasts. otherwise going forecast look good. We can really use
some rain around here.

Przybylinski

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Monday Evening)
Issued at 607 PM CDT Sun Jul 27 2014

Gusty northwest winds will prevail through the forecast period,
with gusts diminishing after sunset this evening, only to return
by mid- to late morning on Monday. VFR flight conditions are also
expected to continue. Area of stratocu north of area terminals
continues to dissipate as it edges southward, and given the loss
of heating and continued dry air filtering into the area
overnight, do not expect redevelopment until late Monday morning.
Currently, soundings indicate potential scattered to broken
ceilings Monday, though with bases expected to be around
4000-5000ft, VFR conditions will prevail.

Specifics for KSTL:
Gusty northwest winds will diminish after sunset this evening,
though sustained wind speeds will remain up around 10KT. Gusts
will return by mid- to late morning on Monday, though are expected
to be lower than the gusts experienced today, and remain
northwesterly. Currently, mostly clear conditions look to continue
through the overnight hours, with diurnal cumulus developing by
around 15Z Monday. Soundings indicate scattered to broken
coverage, particularly during the late morning and early
afternoon, but with bases around 5000ft, VFR conditions will
continue.

JP

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 280154
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
854 PM CDT Sun Jul 27 2014

.UPDATE:
Issued at 851 PM CDT Sun Jul 27 2014
Issued at 558 PM CDT Sun Jul 27 2014

Just made some minor changes to the temperature and wind
forecasts. otherwise going forecast look good. We can really use
some rain around here.

Przybylinski

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Monday Evening)
Issued at 607 PM CDT Sun Jul 27 2014

Gusty northwest winds will prevail through the forecast period,
with gusts diminishing after sunset this evening, only to return
by mid- to late morning on Monday. VFR flight conditions are also
expected to continue. Area of stratocu north of area terminals
continues to dissipate as it edges southward, and given the loss
of heating and continued dry air filtering into the area
overnight, do not expect redevelopment until late Monday morning.
Currently, soundings indicate potential scattered to broken
ceilings Monday, though with bases expected to be around
4000-5000ft, VFR conditions will prevail.

Specifics for KSTL:
Gusty northwest winds will diminish after sunset this evening,
though sustained wind speeds will remain up around 10KT. Gusts
will return by mid- to late morning on Monday, though are expected
to be lower than the gusts experienced today, and remain
northwesterly. Currently, mostly clear conditions look to continue
through the overnight hours, with diurnal cumulus developing by
around 15Z Monday. Soundings indicate scattered to broken
coverage, particularly during the late morning and early
afternoon, but with bases around 5000ft, VFR conditions will
continue.

JP

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 272316
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
616 PM CDT Sun Jul 27 2014

.UPDATE:
Issued at 558 PM CDT Sun Jul 27 2014

Made some minor changes to the temperature and wind forecasts for
the next three hours. Will see how quickly temperatures fall from
sunset and forward. Kept surface winds up a bit for the near short
term ending at 0200 UTC. Still a good pressure gradient exists.

Przybylinski

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Monday Evening)
Issued at 607 PM CDT Sun Jul 27 2014

Gusty northwest winds will prevail through the forecast period,
with gusts diminishing after sunset this evening, only to return
by mid- to late morning on Monday. VFR flight conditions are also
expected to continue. Area of stratocu north of area terminals
continues to dissipate as it edges southward, and given the loss
of heating and continued dry air filtering into the area
overnight, do not expect redevelopment until late Monday morning.
Currently, soundings indicate potential scattered to broken
ceilings Monday, though with bases expected to be around
4000-5000ft, VFR conditions will prevail.

Specifics for KSTL:
Gusty northwest winds will diminish after sunset this evening,
though sustained wind speeds will remain up around 10KT. Gusts
will return by mid- to late morning on Monday, though are expected
to be lower than the gusts experienced today, and remain
northwesterly. Currently, mostly clear conditions look to continue
through the overnight hours, with diurnal cumulus developing by
around 15Z Monday. Soundings indicate scattered to broken
coverage, particularly during the late morning and early
afternoon, but with bases around 5000ft, VFR conditions will
continue.

JP

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 272316
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
616 PM CDT Sun Jul 27 2014

.UPDATE:
Issued at 558 PM CDT Sun Jul 27 2014

Made some minor changes to the temperature and wind forecasts for
the next three hours. Will see how quickly temperatures fall from
sunset and forward. Kept surface winds up a bit for the near short
term ending at 0200 UTC. Still a good pressure gradient exists.

Przybylinski

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Monday Evening)
Issued at 607 PM CDT Sun Jul 27 2014

Gusty northwest winds will prevail through the forecast period,
with gusts diminishing after sunset this evening, only to return
by mid- to late morning on Monday. VFR flight conditions are also
expected to continue. Area of stratocu north of area terminals
continues to dissipate as it edges southward, and given the loss
of heating and continued dry air filtering into the area
overnight, do not expect redevelopment until late Monday morning.
Currently, soundings indicate potential scattered to broken
ceilings Monday, though with bases expected to be around
4000-5000ft, VFR conditions will prevail.

Specifics for KSTL:
Gusty northwest winds will diminish after sunset this evening,
though sustained wind speeds will remain up around 10KT. Gusts
will return by mid- to late morning on Monday, though are expected
to be lower than the gusts experienced today, and remain
northwesterly. Currently, mostly clear conditions look to continue
through the overnight hours, with diurnal cumulus developing by
around 15Z Monday. Soundings indicate scattered to broken
coverage, particularly during the late morning and early
afternoon, but with bases around 5000ft, VFR conditions will
continue.

JP

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 272301
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
601 PM CDT Sun Jul 27 2014

.UPDATE:
Issued at 558 PM CDT Sun Jul 27 2014

Made some minor changes to the temperature and wind forecasts for
the next three hours. Will see how quickly temperatures fall from
sunset and forward. Kept surface winds up a bit for the near short
term ending at 0200 UTC. Still a good pressure gradient exists.

Przybylinski

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1245 PM CDT Sun Jul 27 2014

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. A large area of stratocumulus clouds is
headed south through Iowa toward the area; however ceilings are
AOA 3500 FT all the way up into Minnesota and Wisconsin. Also,
guidance is indicating that the leading edge of this cloud deck
will likely continue to dissipate this afternoon into the evening.
There may be some redevelopment tonight, tho am not confident it
will become a solid ceiling again. If it does, it should be
between 2000-3000FT. Clouds should dissipate by mid-morning Monday
and VFR conditions should prevail after that.

Specifics for KSTL:

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. Some uncertainty as to how far south
the large area of VFR stratocumulus over the Upper Midwest will
get, but current indications are that it will dissipate before
reaching Lambert. There may be some redevelopment tonight, tho am
not confident it will become a solid ceiling again. If it does, it
should be between 2000-3000FT. Clouds should dissipate by mid-
morning Monday and VFR conditions should prevail after that.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 272035
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
335 PM CDT Sun Jul 27 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1245 PM CDT Sun Jul 27 2014

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. A large area of stratocumulus clouds is
headed south through Iowa toward the area; however ceilings are
AOA 3500 FT all the way up into Minnesota and Wisconsin. Also,
guidance is indicating that the leading edge of this cloud deck
will likely continue to dissipate this afternoon into the evening.
There may be some redevelopment tonight, tho am not confident it
will become a solid ceiling again. If it does, it should be
between 2000-3000FT. Clouds should dissipate by mid-morning Monday
and VFR conditions should prevail after that.

Specifics for KSTL:

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. Some uncertainty as to how far south
the large area of VFR stratocumulus over the Upper Midwest will
get, but current indications are that it will dissipate before
reaching Lambert. There may be some redevelopment tonight, tho am
not confident it will become a solid ceiling again. If it does, it
should be between 2000-3000FT. Clouds should dissipate by mid-
morning Monday and VFR conditions should prevail after that.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX






000
FXUS63 KLSX 272035
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
335 PM CDT Sun Jul 27 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 335 PM CDT Sun Jul 27 2014

Primary cold front is through the area, and the secondary push of
cooler and much drier air is filtering through the area at this
time.  Dewpoint temperatures are already falling through the 60s
into the 50s and ambient temperatures are either steady or have
fallen a degree or so across parts of central and northeast Missouri
and west central Illinois.  The primary forecast challenge for
tonight will be temperatures and cloud cover behind the front.  The
shortwave over the Upper Midwest is continuing to dig to the
east-southeast and a broad swath of stratocumulus is following in
its wake.  Some of the strato-cu is undoubtedly diurnally driven and
will dissipate.  However, some of it looks thick enough to make it
into the area.  Not very confident on areal coverage tonight so have
only few-scattered clouds in the forecast.  MOS lows look reasonable
so followed them closely.

Carney

.LONG TERM:  (Monday through Next Sunday)
Issued at 335 PM CDT Sun Jul 27 2014

A deep longwave upper TROF will dominate eastern North America thru
the period, resulting in NW flow over our region.  An extended
period of below normal temps should be the result with maxes in the
upper 70s and low 80s each day with mins in the 50s and low 60s.
Quite a treat for the climatologically hottest time of the year.

The NW upper flow is expected to initially give us dry wx thru
Wednesday night, but what looks to be a bit stronger non-sheared
disturbances trickling down for Thursday thru Saturday with a bit
more moisture thru the column in place looks to be good enough for a
low PoP at this time for what should be diurnally driven SHRA/TSRA.

TES

&&

.AVIATION:  (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1245 PM CDT Sun Jul 27 2014

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. A large area of stratocumulus clouds is
headed south through Iowa toward the area; however ceilings are
AOA 3500 FT all the way up into Minnesota and Wisconsin. Also,
guidance is indicating that the leading edge of this cloud deck
will likely continue to dissipate this afternoon into the evening.
There may be some redevelopment tonight, tho am not confident it
will become a solid ceiling again. If it does, it should be
between 2000-3000FT. Clouds should dissipate by mid-morning Monday
and VFR conditions should prevail after that.

Specifics for KSTL:

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. Some uncertainty as to how far south
the large area of VFR stratocumulus over the Upper Midwest will
get, but current indications are that it will dissipate before
reaching Lambert. There may be some redevelopment tonight, tho am
not confident it will become a solid ceiling again. If it does, it
should be between 2000-3000FT. Clouds should dissipate by mid-
morning Monday and VFR conditions should prevail after that.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX





000
FXUS63 KLSX 271807
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
107 PM CDT Sun Jul 27 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 234 AM CDT Sun Jul 27 2014

The cold front has been rather slow moving thus far and stretched
across eastern IA through northwest MO into central KS at 07z.
Areas of fog have developed across portions of northeast Missouri
and west central Illinois where there was a bit more precipitation
yesterday and and the winds were light. The CWA was also void of
any precipitation. The closest showers and thunderstorms were
occurring in an east-west band from just northeast of KUIN to
east of KCMI and were associated with a region of moisture
convergence associated with the westerly low level wind max. The
shoft range guidance suggests that there could be some westward
development into the CWA over the next few hours, but the general
trend should be for this to push east through the early morning
hours as the cold front moves southeast. The cold front motion
will accelerate as the morning progresses in response to the upper
low/trof over the upper MS Valley digging southeastward toward the
Great Lakes. The northwest wind shift with the cold front should
also keep the fog as a short-lived phenomena. The air mass ahead
of the front will remain sufficiently moist and unstable to merit
low chance pops until fropa through the CWA around midday. Increasing
northwest winds in the wake of the front will usher drier and
cooler air into the region, predominately this afternoon.

Glass

.LONG TERM:  (Tonight through Saturday)
Issued at 234 AM CDT Sun Jul 27 2014

Surface high pressure will slowly build into the area tonight and
in ernest on Monday as the high center settles southward into the
northern Plains. The high will dominate the region through the
first part of the week with a deep longwave trof anchored across
eastern NOAM, bringing more below average temperatures. During the
later part of the week, there will be a few disturbances aloft
dropping southeastward across the region and into the base of the
upper trof. These features will have a weak surface reflection but
could generate a few showers and/or thunderstorms while also
helping maintain the below average temps.

Glass

&&

.AVIATION:  (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1245 PM CDT Sun Jul 27 2014

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. A large area of stratocumulus clouds is
headed south through Iowa toward the area; however ceilings are
AOA 3500 FT all the way up into Minnesota and Wisconsin. Also,
guidance is indicating that the leading edge of this cloud deck
will likely continue to dissipate this afternoon into the evening.
There may be some redevelopment tonight, tho am not confident it
will become a solid ceiling again. If it does, it should be
between 2000-3000FT. Clouds should dissipate by mid-morning Monday
and VFR conditions should prevail after that.

Specifics for KSTL:

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. Some uncertainty as to how far south
the large area of VFR stratocumulus over the Upper Midwest will
get, but current indications are that it will dissipate before
reaching Lambert. There may be some redevelopment tonight, tho am
not confident it will become a solid ceiling again. If it does, it
should be between 2000-3000FT. Clouds should dissipate by mid-
morning Monday and VFR conditions should prevail after that.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 271807
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
107 PM CDT Sun Jul 27 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 234 AM CDT Sun Jul 27 2014

The cold front has been rather slow moving thus far and stretched
across eastern IA through northwest MO into central KS at 07z.
Areas of fog have developed across portions of northeast Missouri
and west central Illinois where there was a bit more precipitation
yesterday and and the winds were light. The CWA was also void of
any precipitation. The closest showers and thunderstorms were
occurring in an east-west band from just northeast of KUIN to
east of KCMI and were associated with a region of moisture
convergence associated with the westerly low level wind max. The
shoft range guidance suggests that there could be some westward
development into the CWA over the next few hours, but the general
trend should be for this to push east through the early morning
hours as the cold front moves southeast. The cold front motion
will accelerate as the morning progresses in response to the upper
low/trof over the upper MS Valley digging southeastward toward the
Great Lakes. The northwest wind shift with the cold front should
also keep the fog as a short-lived phenomena. The air mass ahead
of the front will remain sufficiently moist and unstable to merit
low chance pops until fropa through the CWA around midday. Increasing
northwest winds in the wake of the front will usher drier and
cooler air into the region, predominately this afternoon.

Glass

.LONG TERM:  (Tonight through Saturday)
Issued at 234 AM CDT Sun Jul 27 2014

Surface high pressure will slowly build into the area tonight and
in ernest on Monday as the high center settles southward into the
northern Plains. The high will dominate the region through the
first part of the week with a deep longwave trof anchored across
eastern NOAM, bringing more below average temperatures. During the
later part of the week, there will be a few disturbances aloft
dropping southeastward across the region and into the base of the
upper trof. These features will have a weak surface reflection but
could generate a few showers and/or thunderstorms while also
helping maintain the below average temps.

Glass

&&

.AVIATION:  (For the 18z TAFs through 18z Monday Afternoon)
Issued at 1245 PM CDT Sun Jul 27 2014

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. A large area of stratocumulus clouds is
headed south through Iowa toward the area; however ceilings are
AOA 3500 FT all the way up into Minnesota and Wisconsin. Also,
guidance is indicating that the leading edge of this cloud deck
will likely continue to dissipate this afternoon into the evening.
There may be some redevelopment tonight, tho am not confident it
will become a solid ceiling again. If it does, it should be
between 2000-3000FT. Clouds should dissipate by mid-morning Monday
and VFR conditions should prevail after that.

Specifics for KSTL:

Expect VFR flight conditions and gusty northwest wind to continue
to prevail this afternoon. Some uncertainty as to how far south
the large area of VFR stratocumulus over the Upper Midwest will
get, but current indications are that it will dissipate before
reaching Lambert. There may be some redevelopment tonight, tho am
not confident it will become a solid ceiling again. If it does, it
should be between 2000-3000FT. Clouds should dissipate by mid-
morning Monday and VFR conditions should prevail after that.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 271022
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
522 AM CDT Sun Jul 27 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 234 AM CDT Sun Jul 27 2014

The cold front has been rather slow moving thus far and stretched
across eastern IA through northwest MO into central KS at 07z.
Areas of fog have developed across portions of northeast Missouri
and west central Illinois where there was a bit more precipitation
yesterday and and the winds were light. The CWA was also void of
any precipitation. The closest showers and thunderstorms were
occurring in an east-west band from just northeast of KUIN to
east of KCMI and were associated with a region of moisture
convergence associated with the westerly low level wind max. The
shoft range guidance suggests that there could be some westward
development into the CWA over the next few hours, but the general
trend should be for this to push east through the early morning
hours as the cold front moves southeast. The cold front motion
will accelerate as the morning progresses in response to the upper
low/trof over the upper MS Valley digging southeastward toward the
Great Lakes. The northwest wind shift with the cold front should
also keep the fog as a short-lived phenomena. The air mass ahead
of the front will remain sufficiently moist and unstable to merit
low chance pops until fropa through the CWA around midday. Increasing
northwest winds in the wake of the front will usher drier and
cooler air into the region, predominately this afternoon.

Glass

.LONG TERM:  (Tonight through Saturday)
Issued at 234 AM CDT Sun Jul 27 2014

Surface high pressure will slowly build into the area tonight and
in ernest on Monday as the high center settles southward into the
northern Plains. The high will dominate the region through the
first part of the week with a deep longwave trof anchored across
eastern NOAM, bringing more below average temperatures. During the
later part of the week, there will be a few disturbances aloft
dropping southeastward across the region and into the base of the
upper trof. These features will have a weak surface reflection but
could generate a few showers and/or thunderstorms while also
helping maintain the below average temps.

Glass

&&

.AVIATION:  (For the 12z TAFs through 12z Monday Morning)
Issued at 514 AM CDT Sun Jul 27 2014

Cold front now pushing through the TAF sites. KUIN under blanket
of dense fog ahead of the front, but this should break up rapidly
by around 12Z. Otherwise VFR conditions are expected through this
TAF period. Surface winds will increase by midday and will likely
gust over 20 knots through the afternoon. Winds will diminish
rapidly after sunset.

Specifics for KSTL: VFR conditions expected. Surface winds will
increase by midday and could gust over 20 knots at times through
the afternoon. Winds will diminsh rapidly after sunset.

Browning

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 271022
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
522 AM CDT Sun Jul 27 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 234 AM CDT Sun Jul 27 2014

The cold front has been rather slow moving thus far and stretched
across eastern IA through northwest MO into central KS at 07z.
Areas of fog have developed across portions of northeast Missouri
and west central Illinois where there was a bit more precipitation
yesterday and and the winds were light. The CWA was also void of
any precipitation. The closest showers and thunderstorms were
occurring in an east-west band from just northeast of KUIN to
east of KCMI and were associated with a region of moisture
convergence associated with the westerly low level wind max. The
shoft range guidance suggests that there could be some westward
development into the CWA over the next few hours, but the general
trend should be for this to push east through the early morning
hours as the cold front moves southeast. The cold front motion
will accelerate as the morning progresses in response to the upper
low/trof over the upper MS Valley digging southeastward toward the
Great Lakes. The northwest wind shift with the cold front should
also keep the fog as a short-lived phenomena. The air mass ahead
of the front will remain sufficiently moist and unstable to merit
low chance pops until fropa through the CWA around midday. Increasing
northwest winds in the wake of the front will usher drier and
cooler air into the region, predominately this afternoon.

Glass

.LONG TERM:  (Tonight through Saturday)
Issued at 234 AM CDT Sun Jul 27 2014

Surface high pressure will slowly build into the area tonight and
in ernest on Monday as the high center settles southward into the
northern Plains. The high will dominate the region through the
first part of the week with a deep longwave trof anchored across
eastern NOAM, bringing more below average temperatures. During the
later part of the week, there will be a few disturbances aloft
dropping southeastward across the region and into the base of the
upper trof. These features will have a weak surface reflection but
could generate a few showers and/or thunderstorms while also
helping maintain the below average temps.

Glass

&&

.AVIATION:  (For the 12z TAFs through 12z Monday Morning)
Issued at 514 AM CDT Sun Jul 27 2014

Cold front now pushing through the TAF sites. KUIN under blanket
of dense fog ahead of the front, but this should break up rapidly
by around 12Z. Otherwise VFR conditions are expected through this
TAF period. Surface winds will increase by midday and will likely
gust over 20 knots through the afternoon. Winds will diminish
rapidly after sunset.

Specifics for KSTL: VFR conditions expected. Surface winds will
increase by midday and could gust over 20 knots at times through
the afternoon. Winds will diminsh rapidly after sunset.

Browning

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 270748
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
248 AM CDT Sun Jul 27 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 234 AM CDT Sun Jul 27 2014

The cold front has been rather slow moving thus far and stretched
across eastern IA through northwest MO into central KS at 07z.
Areas of fog have developed across portions of northeast Missouri
and west central Illinois where there was a bit more precipitation
yesterday and and the winds were light. The CWA was also void of
any precipitation. The closest showers and thunderstorms were
occurring in an east-west band from just northeast of KUIN to
east of KCMI and were associated with a region of moisture
convergence associated with the westerly low level wind max. The
shoft range guidance suggests that there could be some westward
development into the CWA over the next few hours, but the general
trend should be for this to push east through the early morning
hours as the cold front moves southeast. The cold front motion
will accelerate as the morning progresses in response to the upper
low/trof over the upper MS Valley digging southeastward toward the
Great Lakes. The northwest wind shift with the cold front should
also keep the fog as a short-lived phenomena. The air mass ahead
of the front will remain sufficiently moist and unstable to merit
low chance pops until fropa through the CWA around midday. Increasing
northwest winds in the wake of the front will usher drier and
cooler air into the region, predominately this afternoon.

Glass

.LONG TERM:  (Tonight through Saturday)
Issued at 234 AM CDT Sun Jul 27 2014

Surface high pressure will slowly build into the area tonight and
in ernest on Monday as the high center settles southward into the
northern Plains. The high will dominate the region through the
first part of the week with a deep longwave trof anchored across
eastern NOAM, bringing more below average temperatures. During the
later part of the week, there will be a few disturbances aloft
dropping southeastward across the region and into the base of the
upper trof. These features will have a weak surface reflection but
could generate a few showers and/or thunderstorms while also
helping maintain the below average temps.

Glass

&&

.AVIATION:  (For the 06z TAFs through 06z Sunday Night)
Issued at 1144 PM CDT Sat Jul 26 2014

Latest surface analysis continues to show slow progress with the
frontal boundaries to our north and west. Latest surface analysis
shows stationary front extending from central Wisconsin to an area
of weak low pressure west of Kansas City then southwest into
southwest Kansas. This front has moved little within the past 3
hours. Secondary frontal boundary extends from southern Minnesota
through northwest Kansas. This front has also made little progress
to the southeast. Upstairs 500 mb shortwave from over the High
Plains will slide southeast across the upper and parts of Mid-
Mississippi Valley region by 1200 - 1800 UTC time frame. Cold
front forecast east-central Missouri between 1200-1400 UTC.

Specifics for KSTL::Light and variable winds will become west-
southwesterly 5 to 8 kts after 0900 UTC. isolated showers and
thunderstorms are possible after 1000 UTC but should be ending by
1200 UTC. Expect cold front to move across STL between 1200 and
1400 UTC. Expected scattered showers to end after 1200 UTC.

Przybylinski

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 270504
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1204 AM CDT Sun Jul 27 2014

.UPDATE:
Issued at 935 PM CDT Sat Jul 26 2014

Trying to pin down convection threat for the remainder of tonight
remains somewhat of a head scratcher.  However, as we dig into the
details of the 00z UA data becoming doubtful that the the storm-
free conditions we are currently experiencing will continue
throughout the entire night.

Although all of the 00z raobs in the area are indicating that the
strong cap is persisting throughout the region early this evening, water
vapor imagery indicates that strong mid level WNW flow is
beginning to dig south as trof rotates around the unseasonably
strong mid level low near nw MN, and this should drag some cooler
mid level air into northern sections of the CWA during the
predawn hours aiding in the erosion of this wedge of warm mid
level air. In addition to this cooling and dynamics with the
shortwave, low level forcing should also be increasing as cold
front works its way into the mid-Mississippi Valley. And...
while the "cooled" air from the rain associated with this
afternoon`s MCV is currently parked over the CWA, airmass west of
our area (that missed out on the rain) remains very unstable at
02z, with MLCAPES of 4000-5000 J/KG, and this air will be
advected back into our area due to weak but persistent westerly
low level flow.

So...whether the storms form upstream and advect into the area,
or form in situ near the Mississippi River as suggested by the
latest HRRR, 18z NAM, and latest RUC runs, thunderstorms will
remain in the forecast overnight. Overall, think current trends of
ramping PoPs up after 05z is very reasonable, with the greatest
PoPs over northern and central sections of the CWA, where forcing
should be the greatest. A conditional threat of severe
thunderstorm is still in the cards for the region as noted in the
SWODY1, as large scale shear will be increasing as the westerlies
dip into the mid- Mississippi Valley and interacts with the
residually unstable ams.

Truett

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM:  (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014

The cold front is expected to push through early Sunday morning.  A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it.  The cooling effects will not be
felt too much early on, with another warm day expected:  max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.

After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region.  This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps.  For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.

TES

&&

.AVIATION:  (For the 06z TAFs through 06z Sunday Night)
Issued at 1144 PM CDT Sat Jul 26 2014

Latest surface analysis continues to show slow progress with the
frontal boundaries to our north and west. Latest surface analysis
shows stationary front extending from central Wisconsin to an area
of weak low pressure west of Kansas City then southwest into
southwest Kansas. This front has moved little within the past 3
hours. Secondary frontal boundary extends from southern Minnesota
through northwest Kansas. This front has also made little progress
to the southeast. Upstairs 500 mb shortwave from over the High
Plains will slide southeast across the upper and parts of Mid-
Mississippi Valley region by 1200 - 1800 UTC time frame. Cold
front forecast east-central Missouri between 1200-1400 UTC.

Specifics for KSTL::Light and variable winds will become west-
southwesterly 5 to 8 kts after 0900 UTC. isolated showers and
thunderstorms are possible after 1000 UTC but should be ending by
1200 UTC. Expect cold front to move across STL between 1200 and
1400 UTC. Expected scattered showers to end after 1200 UTC.

Przybylinski

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 270504
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1204 AM CDT Sun Jul 27 2014

.UPDATE:
Issued at 935 PM CDT Sat Jul 26 2014

Trying to pin down convection threat for the remainder of tonight
remains somewhat of a head scratcher.  However, as we dig into the
details of the 00z UA data becoming doubtful that the the storm-
free conditions we are currently experiencing will continue
throughout the entire night.

Although all of the 00z raobs in the area are indicating that the
strong cap is persisting throughout the region early this evening, water
vapor imagery indicates that strong mid level WNW flow is
beginning to dig south as trof rotates around the unseasonably
strong mid level low near nw MN, and this should drag some cooler
mid level air into northern sections of the CWA during the
predawn hours aiding in the erosion of this wedge of warm mid
level air. In addition to this cooling and dynamics with the
shortwave, low level forcing should also be increasing as cold
front works its way into the mid-Mississippi Valley. And...
while the "cooled" air from the rain associated with this
afternoon`s MCV is currently parked over the CWA, airmass west of
our area (that missed out on the rain) remains very unstable at
02z, with MLCAPES of 4000-5000 J/KG, and this air will be
advected back into our area due to weak but persistent westerly
low level flow.

So...whether the storms form upstream and advect into the area,
or form in situ near the Mississippi River as suggested by the
latest HRRR, 18z NAM, and latest RUC runs, thunderstorms will
remain in the forecast overnight. Overall, think current trends of
ramping PoPs up after 05z is very reasonable, with the greatest
PoPs over northern and central sections of the CWA, where forcing
should be the greatest. A conditional threat of severe
thunderstorm is still in the cards for the region as noted in the
SWODY1, as large scale shear will be increasing as the westerlies
dip into the mid- Mississippi Valley and interacts with the
residually unstable ams.

Truett

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM:  (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014

The cold front is expected to push through early Sunday morning.  A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it.  The cooling effects will not be
felt too much early on, with another warm day expected:  max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.

After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region.  This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps.  For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.

TES

&&

.AVIATION:  (For the 06z TAFs through 06z Sunday Night)
Issued at 1144 PM CDT Sat Jul 26 2014

Latest surface analysis continues to show slow progress with the
frontal boundaries to our north and west. Latest surface analysis
shows stationary front extending from central Wisconsin to an area
of weak low pressure west of Kansas City then southwest into
southwest Kansas. This front has moved little within the past 3
hours. Secondary frontal boundary extends from southern Minnesota
through northwest Kansas. This front has also made little progress
to the southeast. Upstairs 500 mb shortwave from over the High
Plains will slide southeast across the upper and parts of Mid-
Mississippi Valley region by 1200 - 1800 UTC time frame. Cold
front forecast east-central Missouri between 1200-1400 UTC.

Specifics for KSTL::Light and variable winds will become west-
southwesterly 5 to 8 kts after 0900 UTC. isolated showers and
thunderstorms are possible after 1000 UTC but should be ending by
1200 UTC. Expect cold front to move across STL between 1200 and
1400 UTC. Expected scattered showers to end after 1200 UTC.

Przybylinski

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 270242
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
942 PM CDT Sat Jul 26 2014

.UPDATE:
Issued at 935 PM CDT Sat Jul 26 2014

Trying to pin down convection threat for the remainder of tonight
remains somewhat of a head scratcher.  However, as we dig into the
details of the 00z UA data becoming doubtful that the the storm-
free conditions we are currently experiencing will continue
throughout the entire night.

Although all of the 00z raobs in the area are indicating that the
strong cap is persisting throughout the region early this evening, water
vapor imagery indicates that strong mid level WNW flow is
beginning to dig south as trof rotates around the unseasonably
strong mid level low near nw MN, and this should drag some cooler
mid level air into northern sections of the CWA during the
predawn hours aiding in the erosion of this wedge of warm mid
level air. In addition to this cooling and dynamics with the
shortwave, low level forcing should also be increasing as cold
front works its way into the mid-Mississippi Valley. And...
while the "cooled" air from the rain associated with this
afternoon`s MCV is currently parked over the CWA, airmass west of
our area (that missed out on the rain) remains very unstable at
02z, with MLCAPES of 4000-5000 J/KG, and this air will be
advected back into our area due to weak but persistent westerly
low level flow.

So...whether the storms form upstream and advect into the area,
or form in situ near the Mississippi River as suggested by the
latest HRRR, 18z NAM, and latest RUC runs, thunderstorms will
remain in the forecast overnight. Overall, think current trends of
ramping PoPs up after 05z is very reasonable, with the greatest
PoPs over northern and central sections of the CWA, where forcing
should be the greatest. A conditional threat of severe
thunderstorm is still in the cards for the region as noted in the
SWODY1, as large scale shear will be increasing as the westerlies
dip into the mid- Mississippi Valley and interacts with the
residually unstable ams.

Truett

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM:  (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014

The cold front is expected to push through early Sunday morning.  A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it.  The cooling effects will not be
felt too much early on, with another warm day expected:  max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.

After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region.  This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps.  For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Sunday Evening)
Issued at 655 PM CDT Sat Jul 26 2014

Mesoscale Convective Vortex (MCV) moved across north central
Missouri through southwest Illinois. Scattered light showers was
associated with the MVC while strong thunderstorms first formed
along the northeast quadrant of the MVC and eventually build ahead
of this featuer over central and parts of southeast Illinois.
Scattered light showers will continue over STL terminarls but will
end over UIN and eventually end over COU after 0200 UTC. Cold
front will move through UIN and COU between 0800 and 1000 UTC and
STL area after 1200 UTC. Scattered showers and thunderstorms still
possible with the passage of the cold front.

Specifics for KSTL:
Scattered showers will continue over area through 0200 UTC then
next chance for scattered showers and thunderstorms may occur with
the passage of the cold front before 1200 UTC. Southwest winds
will become northwest 10 to 15 mph after the passage of the cold
front.

Przybylinski

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 270242
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
942 PM CDT Sat Jul 26 2014

.UPDATE:
Issued at 935 PM CDT Sat Jul 26 2014

Trying to pin down convection threat for the remainder of tonight
remains somewhat of a head scratcher.  However, as we dig into the
details of the 00z UA data becoming doubtful that the the storm-
free conditions we are currently experiencing will continue
throughout the entire night.

Although all of the 00z raobs in the area are indicating that the
strong cap is persisting throughout the region early this evening, water
vapor imagery indicates that strong mid level WNW flow is
beginning to dig south as trof rotates around the unseasonably
strong mid level low near nw MN, and this should drag some cooler
mid level air into northern sections of the CWA during the
predawn hours aiding in the erosion of this wedge of warm mid
level air. In addition to this cooling and dynamics with the
shortwave, low level forcing should also be increasing as cold
front works its way into the mid-Mississippi Valley. And...
while the "cooled" air from the rain associated with this
afternoon`s MCV is currently parked over the CWA, airmass west of
our area (that missed out on the rain) remains very unstable at
02z, with MLCAPES of 4000-5000 J/KG, and this air will be
advected back into our area due to weak but persistent westerly
low level flow.

So...whether the storms form upstream and advect into the area,
or form in situ near the Mississippi River as suggested by the
latest HRRR, 18z NAM, and latest RUC runs, thunderstorms will
remain in the forecast overnight. Overall, think current trends of
ramping PoPs up after 05z is very reasonable, with the greatest
PoPs over northern and central sections of the CWA, where forcing
should be the greatest. A conditional threat of severe
thunderstorm is still in the cards for the region as noted in the
SWODY1, as large scale shear will be increasing as the westerlies
dip into the mid- Mississippi Valley and interacts with the
residually unstable ams.

Truett

&&

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM:  (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014

The cold front is expected to push through early Sunday morning.  A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it.  The cooling effects will not be
felt too much early on, with another warm day expected:  max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.

After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region.  This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps.  For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Sunday Evening)
Issued at 655 PM CDT Sat Jul 26 2014

Mesoscale Convective Vortex (MCV) moved across north central
Missouri through southwest Illinois. Scattered light showers was
associated with the MVC while strong thunderstorms first formed
along the northeast quadrant of the MVC and eventually build ahead
of this featuer over central and parts of southeast Illinois.
Scattered light showers will continue over STL terminarls but will
end over UIN and eventually end over COU after 0200 UTC. Cold
front will move through UIN and COU between 0800 and 1000 UTC and
STL area after 1200 UTC. Scattered showers and thunderstorms still
possible with the passage of the cold front.

Specifics for KSTL:
Scattered showers will continue over area through 0200 UTC then
next chance for scattered showers and thunderstorms may occur with
the passage of the cold front before 1200 UTC. Southwest winds
will become northwest 10 to 15 mph after the passage of the cold
front.

Przybylinski

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 270012
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
712 PM CDT Sat Jul 26 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM:  (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014

The cold front is expected to push through early Sunday morning.  A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it.  The cooling effects will not be
felt too much early on, with another warm day expected:  max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.

After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region.  This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps.  For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Sunday Evening)
Issued at 655 PM CDT Sat Jul 26 2014

Mesoscale Convective Vortex (MCV) moved across north central
Missouri through southwest Illinois. Scattered light showers was
associated with the MVC while strong thunderstorms first formed
along the northeast quadrant of the MVC and eventually build ahead
of this featuer over central and parts of southeast Illinois.
Scattered light showers will continue over STL terminarls but will
end over UIN and eventually end over COU after 0200 UTC. Cold
front will move through UIN and COU between 0800 and 1000 UTC and
STL area after 1200 UTC. Scattered showers and thunderstorms still
possible with the passage of the cold front.

Specifics for KSTL:
Scattered showers will continue over area through 0200 UTC then
next chance for scattered showers and thunderstorms may occur with
the passage of the cold front before 1200 UTC. Southwest winds
will become northwest 10 to 15 mph after the passage of the cold
front.

Przybylinski

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX







000
FXUS63 KLSX 270012
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
712 PM CDT Sat Jul 26 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM:  (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014

The cold front is expected to push through early Sunday morning.  A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it.  The cooling effects will not be
felt too much early on, with another warm day expected:  max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.

After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region.  This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps.  For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.

TES

&&

.AVIATION:  (For the 00z TAFs through 00z Sunday Evening)
Issued at 655 PM CDT Sat Jul 26 2014

Mesoscale Convective Vortex (MCV) moved across north central
Missouri through southwest Illinois. Scattered light showers was
associated with the MVC while strong thunderstorms first formed
along the northeast quadrant of the MVC and eventually build ahead
of this featuer over central and parts of southeast Illinois.
Scattered light showers will continue over STL terminarls but will
end over UIN and eventually end over COU after 0200 UTC. Cold
front will move through UIN and COU between 0800 and 1000 UTC and
STL area after 1200 UTC. Scattered showers and thunderstorms still
possible with the passage of the cold front.

Specifics for KSTL:
Scattered showers will continue over area through 0200 UTC then
next chance for scattered showers and thunderstorms may occur with
the passage of the cold front before 1200 UTC. Southwest winds
will become northwest 10 to 15 mph after the passage of the cold
front.

Przybylinski

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 262040
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
340 PM CDT Sat Jul 26 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM:  (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014

The cold front is expected to push through early Sunday morning.  A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it.  The cooling effects will not be
felt too much early on, with another warm day expected:  max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.

After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region.  This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps.  For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.

TES

&&

.AVIATION:  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1241 PM CDT Sat Jul 26 2014

Primary concern is thunderstorms this afternoon and evening.
Expecting the precipitation over west central/centra MO to
continue to move eastward. It is unclear yet how much these storms
will strengthen/expand, but some strong wind gusts and hail are
possible with this complex as it moves eastward. Another area of
concern will be in northeast MO/west central IL later this
afternoon/this evening where a complex of severe thunderstorms is
expected to develop and should move rapidly east-southeast. Wind
gusts in excess of 50kts and large hail will be possible with
this cluster. Still some uncertainty on the exact track of the
thunderstorm complex, though the most likely parts of the area to
be affected will be along and north of a line from KIRK to KSLO.

Afterthe storms move through this evening, expect VFR flight
conditions. A cold front will move through early Sunday morning
shifting the wind to the west-northwest.

Specifics for KSTL:

Primary concern at Lambert is the possibility of thunderstorms
early this evening. Current thinking is that the storms over
central/west central Missouri may not affect the terminal, but a
cluster of severe thunderstorms will develop over northern
MO/southern IA and race east-southeast. Think the best threat for
storms will be north of Lambert along and north of a line from
KIRK to KSLO. After storms clear the area this evening expect VFR
flight conditions to prevail. A cold front will pass through the
terminal early Sunday morning which will shift the wind to the
northwest.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 7 PM CDT this evening FOR Franklin MO-
     Jefferson MO-St. Charles MO-St. Louis City MO-St. Louis MO-
     Warren MO.

IL...HEAT ADVISORY until 7 PM CDT this evening FOR Clinton IL-Madison
     IL-Monroe IL-St. Clair IL-Washington IL.

&&

$$

WFO LSX





000
FXUS63 KLSX 262040
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
340 PM CDT Sat Jul 26 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM:  (Sunday through Next Saturday)
Issued at 340 PM CDT Sat Jul 26 2014

The cold front is expected to push through early Sunday morning.  A
minimal rain threat will exist during the morning near it, with a
dry afternoon on tap behind it.  The cooling effects will not be
felt too much early on, with another warm day expected:  max temps
still look to top 90 degrees for most areas near and south of I-70.
The big difference will be lower humidity from today, however.

After Sunday, an extended dry period is forecast as a deep longwave
upper TROF sets up over eastern North America with a stout NW flow
aloft for our region.  This usually means either dry, or surprise
hit-and-run systems this time of year, but almost always means below
average temps.  For now, am going with dry until Thursday, with low
PoPs thereafter as a system works its way down into our region and
stays for a bit.

TES

&&

.AVIATION:  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1241 PM CDT Sat Jul 26 2014

Primary concern is thunderstorms this afternoon and evening.
Expecting the precipitation over west central/centra MO to
continue to move eastward. It is unclear yet how much these storms
will strengthen/expand, but some strong wind gusts and hail are
possible with this complex as it moves eastward. Another area of
concern will be in northeast MO/west central IL later this
afternoon/this evening where a complex of severe thunderstorms is
expected to develop and should move rapidly east-southeast. Wind
gusts in excess of 50kts and large hail will be possible with
this cluster. Still some uncertainty on the exact track of the
thunderstorm complex, though the most likely parts of the area to
be affected will be along and north of a line from KIRK to KSLO.

Afterthe storms move through this evening, expect VFR flight
conditions. A cold front will move through early Sunday morning
shifting the wind to the west-northwest.

Specifics for KSTL:

Primary concern at Lambert is the possibility of thunderstorms
early this evening. Current thinking is that the storms over
central/west central Missouri may not affect the terminal, but a
cluster of severe thunderstorms will develop over northern
MO/southern IA and race east-southeast. Think the best threat for
storms will be north of Lambert along and north of a line from
KIRK to KSLO. After storms clear the area this evening expect VFR
flight conditions to prevail. A cold front will pass through the
terminal early Sunday morning which will shift the wind to the
northwest.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 7 PM CDT this evening FOR Franklin MO-
     Jefferson MO-St. Charles MO-St. Louis City MO-St. Louis MO-
     Warren MO.

IL...HEAT ADVISORY until 7 PM CDT this evening FOR Clinton IL-Madison
     IL-Monroe IL-St. Clair IL-Washington IL.

&&

$$

WFO LSX






000
FXUS63 KLSX 262024
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
324 PM CDT Sat Jul 26 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 324 PM CDT Sat Jul 26 2014

Primary concern continues to be convective trends for this evening.
Current trends are pointing more and more toward there being less
severe weather in our CWFA than previously expected, with the
primary threat for severe storms further north/northeast in
southeast IA and central IL.  A broad area of showers and stratiform
rain associated with an MCV which is spinning its way across the
state is putting the kibosh on much of the instability which was
forecast for late this afternoon/evening.  A limited ribbon of very
high CAPE (MLCAPE in excess of 3500-4000 J/Kg) remains over extreme
northeast MO into southern IA and a much larger area of high CAPE
over central and southern IL.  Storms are already rumbling just
north of our CWFA in southern IA and west central IL and I would
expect these areas of storms to continue to develop and strengthen.
Still cannot rule out severe storms from Kirksville to Quincy and
southeast to Litchfield and possibly Salem...but the probability
seems to be much lower than previously expected.

After the evening severe weather threat has passed, there is still
the possibility that there could be additional development
overnight.  RAP and NAM both show moderate moisture convergence at
850mb ahead of the front and generate QPF in response.  Have left
chance/slight chance PoPs going for most of the area through the
night.  The wind shift associated with the approaching cold front
should be sliding into the northern 1/3 of our CWFA between 09-12Z
with drier low level air trying to nose in.  This should effectively
cut off the chance for additional precip in those areas in the
pre-dawn hours.

Carney

.LONG TERM: (Sunday through Friday)
Issued at 330 AM CDT Sat Jul 26 2014

The cold front will extend from northeast Illinois to around St.
Louis into northern Oklahoma at 12z and should exit the CWA by
early afternoon as the upper low/trof moves southeastward into the
Great Lakes. The precipitation threat will be considerably lower
Sunday morning ahead of the front and I don`t expect to see much.
Increasing northwesterly winds will usher drier and cooler air
into the region during the afternoon in the wake of the front. The
large surface high will settle into the Nation`s midsection on
Monday and then become a dominant feature into midweek as a deep
upper trof persists over eastern NOAM. Below average temperatures
will prevail throughout next week.

Glass

&&

.AVIATION:  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1241 PM CDT Sat Jul 26 2014

Primary concern is thunderstorms this afternoon and evening.
Expecting the precipitation over west central/centra MO to
continue to move eastward. It is unclear yet how much these storms
will strengthen/expand, but some strong wind gusts and hail are
possible with this complex as it moves eastward. Another area of
concern will be in northeast MO/west central IL later this
afternoon/this evening where a complex of severe thunderstorms is
expected to develop and should move rapidly east-southeast. Wind
gusts in excess of 50kts and large hail will be possible with
this cluster. Still some uncertainty on the exact track of the
thunderstorm complex, though the most likely parts of the area to
be affected will be along and north of a line from KIRK to KSLO.

Afterthe storms move through this evening, expect VFR flight
conditions. A cold front will move through early Sunday morning
shifting the wind to the west-northwest.

Specifics for KSTL:

Primary concern at Lambert is the possibility of thunderstorms
early this evening. Current thinking is that the storms over
central/west central Missouri may not affect the terminal, but a
cluster of severe thunderstorms will develop over northern
MO/southern IA and race east-southeast. Think the best threat for
storms will be north of Lambert along and north of a line from
KIRK to KSLO. After storms clear the area this evening expect VFR
flight conditions to prevail. A cold front will pass through the
terminal early Sunday morning which will shift the wind to the
northwest.

Carney

&&

.PRELIMINARY POINT TEMPS/POPS:
Saint Louis     77  90  66  81 /  40  20   0   5
Quincy          71  84  61  77 /  70  10   5  10
Columbia        74  89  62  81 /  20  10   0   5
Jefferson City  75  89  63  81 /  20  10   0   5
Salem           73  90  63  79 /  60  30   0   5
Farmington      75  91  61  80 /  20  30   0   0

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 7 PM CDT this evening FOR Franklin MO-
     Jefferson MO-St. Charles MO-St. Louis City MO-St. Louis MO-
     Warren MO.

IL...HEAT ADVISORY until 7 PM CDT this evening FOR Clinton IL-Madison
     IL-Monroe IL-St. Clair IL-Washington IL.

&&

$$

WFO LSX








000
FXUS63 KLSX 261804
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
104 PM CDT Sat Jul 26 2014

.UPDATE:
Issued at 1241 PM CDT Sat Jul 26 2014

The going forecast for this afternoon still looks pretty good.
Will likely have to bump up PoPs to high chance/likely in an
afternoon update for central MO. MCS generated storms are
maintaining themselves, even strengthening. Current thinking is
that these storms may become marginally severe, but that the main
event will be later this afternoon/this evening developing on the
MO/IA border and moving east-southeast across the northern/eastern
1/3 of the CWFA. Current likely PoPs for late this
afternoon/evening still look pretty good for the moment. Will
discuss further in the full short-term update. Heat advisory looks
to be in good shape at this time so no changes expected.

Carney

&&

.SHORT TERM: (Today and Tonight)
Issued at 330 AM CDT Sat Jul 26 2014

Two major concerns over the next 24 hours are heat today and the
thunderstorm/severe threat this afternoon and tonight. The new
model runs continue to show a very favorable pattern for hot
temperatures today with a prominent low level thermal ridge in
place featuring H85 temperatures greater than +24 degC this
afternoon and veering southwest-westerly lower trop flow. This
should yield high temperatures well into the 90s with the I-70
corridor in line for 95-100. These values agree well with upstream
conditions yesterday. As dicussed in the previous AFD, mixing will
result in a dew point min from the eastern Ozarks into portions of
central MO, with the highest dew points displaced north and east of
the hottest ambient air temperatures. The best overlap and highest
heat indices near 105 degrees will be within metro St. Louis and
a few counties west and east, and I have expanded the heat
advisory this afternoon to account for the slight greater areal
extent.

Now for the thunderstorm and severe weather threat. There could be
a few spotty showers or thunderstorms through mid morning roughly
along an axis from Bourbon to St. Louis to Vandalia where the
westerly LLJ is producing some moisture convergence and there has
been an increase in cloud cover in the last hour or so. Otherwise
the main threat for storms and severe weather looks to be from
around mid-afternoon through this evening. I`m still not exactly
sure how this is going to unfold. The synoptic scale front should
be located across northern MO and central IL and the airmass along
and south of the front will be very unstable and initially capped
owing to warm mid level temperatures. The cap removal is the
largest unknown and could occur via a number of mechanisms - an
eastward moving MCV remnant from the weakening MCS over KS, the
leading edge of height falls/cooling aloft associated with the
southeast moving Saskatchewan upper low/trof, cooling associated
with mid level convection which could form above the EML over
northern MO. The concensus of most of the guidance is that robust
storm development will occur across northern MO into central IL
after 20-21z within the frontal zone. Unseasonably strong deep
layer shear and the high instability favor organized severe. The
overall pattern and shear/strenghening flow aloft are suggestive
of upscale growth from the late afternoon and evening into a forward
propagating MCS moving into the Ohio Valley with a high damaging
wind threat. The SPC moderate risk area has the zone of greatest
probability well delineated at this time.

Glass

.LONG TERM: (Sunday through Friday)
Issued at 330 AM CDT Sat Jul 26 2014

The cold front will extend from northeast Illinois to around St.
Louis into northern Oklahoma at 12z and should exit the CWA by
early afternoon as the upper low/trof moves southeastward into the
Great Lakes. The precipitation threat will be considerably lower
Sunday morning ahead of the front and I don`t expect to see much.
Increasing northwesterly winds will usher drier and cooler air
into the region during the afternoon in the wake of the front. The
large surface high will settle into the Nation`s midsection on
Monday and then become a dominant feature into midweek as a deep
upper trof persists over eastern NOAM. Below average temperatures
will prevail throughout next week.

Glass

&&

.AVIATION:  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1241 PM CDT Sat Jul 26 2014

Primary concern is thunderstorms this afternoon and evening.
Expecting the precipitation over west central/centra MO to
continue to move eastward. It is unclear yet how much these storms
will strengthen/expand, but some strong wind gusts and hail are
possible with this complex as it moves eastward. Another area of
concern will be in northeast MO/west central IL later this
afternoon/this evening where a complex of severe thunderstorms is
expected to develop and should move rapidly east-southeast. Wind
gusts in excess of 50kts and large hail will be possible with
this cluster. Still some uncertainty on the exact track of the
thunderstorm complex, though the most likely parts of the area to
be affected will be along and north of a line from KIRK to KSLO.

Afterthe storms move through this evening, expect VFR flight
conditions. A cold front will move through early Sunday morning
shifting the wind to the west-northwest.

Specifics for KSTL:

Primary concern at Lambert is the possibility of thunderstorms
early this evening. Current thinking is that the storms over
central/west central Missouri may not affect the terminal, but a
cluster of severe thunderstorms will develop over northern
MO/southern IA and race east-southeast. Think the best threat for
storms will be north of Lambert along and north of a line from
KIRK to KSLO. After storms clear the area this evening expect VFR
flight conditions to prevail. A cold front will pass through the
terminal early Sunday morning which will shift the wind to the
northwest.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 7 PM CDT this evening FOR Franklin MO-
     Jefferson MO-St. Charles MO-St. Louis City MO-St. Louis MO-
     Warren MO.

IL...HEAT ADVISORY until 7 PM CDT this evening FOR Clinton IL-Madison
     IL-Monroe IL-St. Clair IL-Washington IL.

&&

$$

WFO LSX








000
FXUS63 KLSX 261804
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
104 PM CDT Sat Jul 26 2014

.UPDATE:
Issued at 1241 PM CDT Sat Jul 26 2014

The going forecast for this afternoon still looks pretty good.
Will likely have to bump up PoPs to high chance/likely in an
afternoon update for central MO. MCS generated storms are
maintaining themselves, even strengthening. Current thinking is
that these storms may become marginally severe, but that the main
event will be later this afternoon/this evening developing on the
MO/IA border and moving east-southeast across the northern/eastern
1/3 of the CWFA. Current likely PoPs for late this
afternoon/evening still look pretty good for the moment. Will
discuss further in the full short-term update. Heat advisory looks
to be in good shape at this time so no changes expected.

Carney

&&

.SHORT TERM: (Today and Tonight)
Issued at 330 AM CDT Sat Jul 26 2014

Two major concerns over the next 24 hours are heat today and the
thunderstorm/severe threat this afternoon and tonight. The new
model runs continue to show a very favorable pattern for hot
temperatures today with a prominent low level thermal ridge in
place featuring H85 temperatures greater than +24 degC this
afternoon and veering southwest-westerly lower trop flow. This
should yield high temperatures well into the 90s with the I-70
corridor in line for 95-100. These values agree well with upstream
conditions yesterday. As dicussed in the previous AFD, mixing will
result in a dew point min from the eastern Ozarks into portions of
central MO, with the highest dew points displaced north and east of
the hottest ambient air temperatures. The best overlap and highest
heat indices near 105 degrees will be within metro St. Louis and
a few counties west and east, and I have expanded the heat
advisory this afternoon to account for the slight greater areal
extent.

Now for the thunderstorm and severe weather threat. There could be
a few spotty showers or thunderstorms through mid morning roughly
along an axis from Bourbon to St. Louis to Vandalia where the
westerly LLJ is producing some moisture convergence and there has
been an increase in cloud cover in the last hour or so. Otherwise
the main threat for storms and severe weather looks to be from
around mid-afternoon through this evening. I`m still not exactly
sure how this is going to unfold. The synoptic scale front should
be located across northern MO and central IL and the airmass along
and south of the front will be very unstable and initially capped
owing to warm mid level temperatures. The cap removal is the
largest unknown and could occur via a number of mechanisms - an
eastward moving MCV remnant from the weakening MCS over KS, the
leading edge of height falls/cooling aloft associated with the
southeast moving Saskatchewan upper low/trof, cooling associated
with mid level convection which could form above the EML over
northern MO. The concensus of most of the guidance is that robust
storm development will occur across northern MO into central IL
after 20-21z within the frontal zone. Unseasonably strong deep
layer shear and the high instability favor organized severe. The
overall pattern and shear/strenghening flow aloft are suggestive
of upscale growth from the late afternoon and evening into a forward
propagating MCS moving into the Ohio Valley with a high damaging
wind threat. The SPC moderate risk area has the zone of greatest
probability well delineated at this time.

Glass

.LONG TERM: (Sunday through Friday)
Issued at 330 AM CDT Sat Jul 26 2014

The cold front will extend from northeast Illinois to around St.
Louis into northern Oklahoma at 12z and should exit the CWA by
early afternoon as the upper low/trof moves southeastward into the
Great Lakes. The precipitation threat will be considerably lower
Sunday morning ahead of the front and I don`t expect to see much.
Increasing northwesterly winds will usher drier and cooler air
into the region during the afternoon in the wake of the front. The
large surface high will settle into the Nation`s midsection on
Monday and then become a dominant feature into midweek as a deep
upper trof persists over eastern NOAM. Below average temperatures
will prevail throughout next week.

Glass

&&

.AVIATION:  (For the 18z TAFs through 18z Sunday Afternoon)
Issued at 1241 PM CDT Sat Jul 26 2014

Primary concern is thunderstorms this afternoon and evening.
Expecting the precipitation over west central/centra MO to
continue to move eastward. It is unclear yet how much these storms
will strengthen/expand, but some strong wind gusts and hail are
possible with this complex as it moves eastward. Another area of
concern will be in northeast MO/west central IL later this
afternoon/this evening where a complex of severe thunderstorms is
expected to develop and should move rapidly east-southeast. Wind
gusts in excess of 50kts and large hail will be possible with
this cluster. Still some uncertainty on the exact track of the
thunderstorm complex, though the most likely parts of the area to
be affected will be along and north of a line from KIRK to KSLO.

Afterthe storms move through this evening, expect VFR flight
conditions. A cold front will move through early Sunday morning
shifting the wind to the west-northwest.

Specifics for KSTL:

Primary concern at Lambert is the possibility of thunderstorms
early this evening. Current thinking is that the storms over
central/west central Missouri may not affect the terminal, but a
cluster of severe thunderstorms will develop over northern
MO/southern IA and race east-southeast. Think the best threat for
storms will be north of Lambert along and north of a line from
KIRK to KSLO. After storms clear the area this evening expect VFR
flight conditions to prevail. A cold front will pass through the
terminal early Sunday morning which will shift the wind to the
northwest.

Carney

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...HEAT ADVISORY until 7 PM CDT this evening FOR Franklin MO-
     Jefferson MO-St. Charles MO-St. Louis City MO-St. Louis MO-
     Warren MO.

IL...HEAT ADVISORY until 7 PM CDT this evening FOR Clinton IL-Madison
     IL-Monroe IL-St. Clair IL-Washington IL.

&&

$$

WFO LSX







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