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000
FXUS63 KLSX 181709
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1209 PM CDT Fri Apr 18 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 328 AM CDT Fri Apr 18 2014

A tranquil Friday looks to be on tap, as the weakening cold front
continues moving southeast out of our area this morning, with any
accompanying shower activity already southeast of our area over
the Missouri bootheel. Skies over central and northeast Missouri
as well as west central Illinois are clear, and expect the
clearing trend to continue from north to south through the morning
hours for the remainder of the forecast area. Rising heights at
500mb will overspread the area today, as a ridge begins to develop
over the middle Mississippi Valley in the wake of the departing
trough. Temperatures today will climb to the mid 60s north to
around 70 for the St. Louis metro area and southern zones, fairly
close to, or even slightly above normal for this time of year.

JP

.LONG TERM:  (Tonight through Thursday)
Issued at 328 AM CDT Fri Apr 18 2014

A big warm up is on the way for the weekend as a ridge amplifies
over the middle Mississippi Valley and southerly flow returns to
the region. Temperatures across the area should have no trouble
reaching the mid 70s on Saturday, and mid to upper 70s Sunday,
with some locations perhaps flirting with the 80 degree mark.
However, by Sunday evening, the 500mb ridge axis will shift east
of the area and flatten slightly, allowing for quasi-zonal to
southwesterly flow over the area late Sunday and into Monday. A
shortwave is progged to move into western Missouri late on Sunday,
and current feeling is that instability will be sufficient for some
thunderstorms to occur, given the warm temperatures and ample
moisture ahead of the system thanks to several days of return
flow. Models have slowed down the progression of this feature
somewhat, thus it looks like this initial shortwave and associated
precipitation will move east across Missouri Sunday night,
leaving much of the day Sunday dry across the forecast area. On
Monday, a reinforcing trough and cold front will move through the
area in the wake of the shortwave, continuing the chance for
showers and thunderstorms through the day on Monday and Monday
night. Both the GFS and ECMWF are in agreement that the front and
associated precipitation will be south of the forecast area by 12Z
Tuesday. Temperatures are still expected to remain near or
slightly above normal.

Beyond next Tuesday, expect another warm up across the area, as
the trough shifts east and deepens over the eastern CONUS and
ridging once again takes place over the middle Mississippi Valley.
Southerly flow will continue to increase Wednesday and Thursday,
with a chance of thunderstorms across the area on Wednesday night
and Thursday in part due to the strengthening warm advection.
Temperatures during this time frame are expected to be in the
middle to upper 70s, continuing the above normal trend. An
intensifying low pressure system over the northern plains is
anticipated to impact the area late next week, though model
agreement is currently lacking in its progression. Thus, feel that
continued warming temperatures and broad brushed chance PoPs
through Thursday are sufficient at this time.

JP

&&

.AVIATION:  (For the 18z TAFs through 18z Saturday Afternoon)
Issued at 1207 PM CDT Fri Apr 18 2014

High pressure will dominate the region resulting in clear skies
and light winds. Some radiational fog will be possible early
Saturday morning at KSUS where the wind will likely be calm. VFR
conditions will continue on Saturday with increasing southeasterly
winds.

Specifics for KSTL:

High pressure will dominate the region resulting in clear skies
and light winds. VFR conditions will continue on Saturday with
increasing southeasterly winds.

Glass

&&

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

$$

WFO LSX








000
FXUS63 KLSX 181124
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
624 AM CDT Fri Apr 18 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 328 AM CDT Fri Apr 18 2014

A tranquil Friday looks to be on tap, as the weakening cold front
continues moving southeast out of our area this morning, with any
accompanying shower activity already southeast of our area over
the Missouri bootheel. Skies over central and northeast Missouri
as well as west central Illinois are clear, and expect the
clearing trend to continue from north to south through the morning
hours for the remainder of the forecast area. Rising heights at
500mb will overspread the area today, as a ridge begins to develop
over the middle Mississippi Valley in the wake of the departing
trough. Temperatures today will climb to the mid 60s north to
around 70 for the St. Louis metro area and southern zones, fairly
close to, or even slightly above normal for this time of year.

JP

.LONG TERM:  (Tonight through Thursday)
Issued at 328 AM CDT Fri Apr 18 2014

A big warm up is on the way for the weekend as a ridge amplifies
over the middle Mississippi Valley and southerly flow returns to
the region. Temperatures across the area should have no trouble
reaching the mid 70s on Saturday, and mid to upper 70s Sunday,
with some locations perhaps flirting with the 80 degree mark.
However, by Sunday evening, the 500mb ridge axis will shift east
of the area and flatten slightly, allowing for quasi-zonal to
southwesterly flow over the area late Sunday and into Monday. A
shortwave is progged to move into western Missouri late on Sunday,
and current feeling is that instability will be sufficient for some
thunderstorms to occur, given the warm temperatures and ample
moisture ahead of the system thanks to several days of return
flow. Models have slowed down the progression of this feature
somewhat, thus it looks like this initial shortwave and associated
precipitation will move east across Missouri Sunday night,
leaving much of the day Sunday dry across the forecast area. On
Monday, a reinforcing trough and cold front will move through the
area in the wake of the shortwave, continuing the chance for
showers and thunderstorms through the day on Monday and Monday
night. Both the GFS and ECMWF are in agreement that the front and
associated precipitation will be south of the forecast area by 12Z
Tuesday. Temperatures are still expected to remain near or
slightly above normal.

Beyond next Tuesday, expect another warm up across the area, as
the trough shifts east and deepens over the eastern CONUS and
ridging once again takes place over the middle Mississippi Valley.
Southerly flow will continue to increase Wednesday and Thursday,
with a chance of thunderstorms across the area on Wednesday night
and Thursday in part due to the strengthening warm advection.
Temperatures during this time frame are expected to be in the
middle to upper 70s, continuing the above normal trend. An
intensifying low pressure system over the northern plains is
anticipated to impact the area late next week, though model
agreement is currently lacking in its progression. Thus, feel that
continued warming temperatures and broad brushed chance PoPs
through Thursday are sufficient at this time.

JP

&&

.AVIATION:  (For the 12z TAFs through 12z Saturday Morning)
Issued at 620 AM CDT Fri Apr 18 2014

Expecting VFR flight conditions and light north-northeast flow to
prevail today. Patchy early morning fog in central Missouri should
dissipate quickly after sunrise. Wind will gradually turn more to
the east and then southeast tonight as a ridge of high pressure
moves across the area.

Specifics for KSTL:

VFR flight conditions and light northerly flow will prevail this
morning. Expect wind to turn to the northeast this afternoon and
then become more east-southeasterly tonight as a ridge of high
pressure moves across the area.

Carney

&&

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

$$

WFO LSX








000
FXUS63 KLSX 180901
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
401 AM CDT Fri Apr 18 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 328 AM CDT Fri Apr 18 2014

A tranquil Friday looks to be on tap, as the weakening cold front
continues moving southeast out of our area this morning, with any
accompanying shower activity already southeast of our area over
the Missouri bootheel. Skies over central and northeast Missouri
as well as west central Illinois are clear, and expect the
clearing trend to continue from north to south through the morning
hours for the remainder of the forecast area. Rising heights at
500mb will overspread the area today, as a ridge begins to develop
over the middle Mississippi Valley in the wake of the departing
trough. Temperatures today will climb to the mid 60s north to
around 70 for the St. Louis metro area and southern zones, fairly
close to, or even slightly above normal for this time of year.

JP

.LONG TERM:  (Tonight through Thursday)
Issued at 328 AM CDT Fri Apr 18 2014

A big warm up is on the way for the weekend as a ridge amplifies
over the middle Mississippi Valley and southerly flow returns to
the region. Temperatures across the area should have no trouble
reaching the mid 70s on Saturday, and mid to upper 70s Sunday,
with some locations perhaps flirting with the 80 degree mark.
However, by Sunday evening, the 500mb ridge axis will shift east
of the area and flatten slightly, allowing for quasi-zonal to
southwesterly flow over the area late Sunday and into Monday. A
shortwave is progged to move into western Missouri late on Sunday,
and current feeling is that instability will be sufficient for some
thunderstorms to occur, given the warm temperatures and ample
moisture ahead of the system thanks to several days of return
flow. Models have slowed down the progression of this feature
somewhat, thus it looks like this initial shortwave and associated
precipitation will move east across Missouri Sunday night,
leaving much of the day Sunday dry across the forecast area. On
Monday, a reinforcing trough and cold front will move through the
area in the wake of the shortwave, continuing the chance for
showers and thunderstorms through the day on Monday and Monday
night. Both the GFS and ECMWF are in agreement that the front and
associated precipitation will be south of the forecast area by 12Z
Tuesday. Temperatures are still expected to remain near or
slightly above normal.

Beyond next Tuesday, expect another warm up across the area, as
the trough shifts east and deepens over the eastern CONUS and
ridging once again takes place over the middle Mississippi Valley.
Southerly flow will continue to increase Wednesday and Thursday,
with a chance of thunderstorms across the area on Wednesday night
and Thursday in part due to the strengthening warm advection.
Temperatures during this time frame are expected to be in the
middle to upper 70s, continuing the above normal trend. An
intensifying low pressure system over the northern plains is
anticipated to impact the area late next week, though model
agreement is currently lacking in its progression. Thus, feel that
continued warming temperatures and broad brushed chance PoPs
through Thursday are sufficient at this time.

JP

&&

.AVIATION:  (For the 06z TAFs through 06z Friday Night)
Issued at 1145 PM CDT Thu Apr 17 2014

VFR conditions expected with mid level cloud cover clearing from
the west early Friday morning. Light north to east wind.

Specifics for KSTL:

VFR with light north to east wind.

CVKING

&&

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

$$

WFO LSX








000
FXUS63 KLSX 180446
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1146 PM CDT Thu Apr 17 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 306 PM CDT Thu Apr 17 2014

Despite cold front moving through region, front is weakening and
moisture is lacking so any precipitation will be very light in
nature. So just have slight chance of showers for portions of west
central/southwestern IL tonight. Otherwise, partly to mostly cloudy
skies to begin scattering out late tonight. Not a lot of caa with
this system, so lows will be in the mid 30s to mid 40s.

Byrd

.LONG TERM:  (Friday through Next Thursday)
Issued at 306 PM CDT Thu Apr 17 2014

Should have a clearing sky from northwest to southeast on Friday as
the surface ridge builds into the area behind the weakening cold
front, and as the upper level trough shifts east of our area.
Tranquil and warmer weather heading into the weekend as an upper
level ridge moves into the area on Saturday behind the upper level
trough/low.  Above normal high temperatures expected on Saturday and
Sunday as southerly surface/low level flow returns.  Low level
moisture and instability will increase over our area Saturday night
and Sunday due to the persistent southerly flow ahead of a slow
moving shortwave over the central Plains.  Scattered showers and a
few thundestorms will likely develop Sunday afternoon across MO, west
of STL.  Showers and a few storms should overspread our area Sunday
night and continue on Monday as this weakening shortwave/upper level
trough moves slowly eastward through the region, while a relatively
weak cold front moves slowly southeastward through our area on
Monday and Monday evening. The precipitation threat should shift
southeast of our forecast area by late Monday night as the upper
level trough shifts east of the region and a surface ridge
builds southeastward into the area behind the cold front.  Only
slight and short lived cooling is expected behind the cold front,
with pronounced warming expected Tuesday night and Wednesday as an
upper level ridge moves eastward into the region and southerly low
level flow returns and strengthens.  The GFS model increases the 850
mb temperatures to 12-16 degrees C by Wednesday night over our
forecast area, whle the ECMWF is not quite as warm.  The GFS model
brings convection into northeast MO and west central IL Wednesday
and Wednesday night due to strong low-mid level warm air advection
ahead of "ridge runner" type shortwaves.  There does seem to be some
convectve feedback in the GFS model at this time leading to
overamplified vort maxes and potentially too much convection
depicted by the model, although the ECMWF also has some qpf
extending south into this area as well.

GKS

&&

.AVIATION:  (For the 06z TAFs through 06z Friday Night)
Issued at 1145 PM CDT Thu Apr 17 2014

VFR conditions expected with mid level cloud cover clearing from
the west early Friday morning. Light north to east wind.

Specifics for KSTL:

VFR with light north to east wind.

CVKING

&&

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

$$

WFO LSX








000
FXUS63 KLSX 172317
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
617 PM CDT Thu Apr 17 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 306 PM CDT Thu Apr 17 2014

Despite cold front moving through region, front is weakening and
moisture is lacking so any precipitation will be very light in
nature. So just have slight chance of showers for portions of west
central/southwestern IL tonight. Otherwise, partly to mostly cloudy
skies to begin scattering out late tonight. Not a lot of caa with
this system, so lows will be in the mid 30s to mid 40s.

Byrd

.LONG TERM:  (Friday through Next Thursday)
Issued at 306 PM CDT Thu Apr 17 2014

Should have a clearing sky from northwest to southeast on Friday as
the surface ridge builds into the area behind the weakening cold
front, and as the upper level trough shifts east of our area.
Tranquil and warmer weather heading into the weekend as an upper
level ridge moves into the area on Saturday behind the upper level
trough/low.  Above normal high temperatures expected on Saturday and
Sunday as southerly surface/low level flow returns.  Low level
moisture and instability will increase over our area Saturday night
and Sunday due to the persistent southerly flow ahead of a slow
moving shortwave over the central Plains.  Scattered showers and a
few thundestorms will likely develop Sunday afternoon across MO, west
of STL.  Showers and a few storms should overspread our area Sunday
night and continue on Monday as this weakening shortwave/upper level
trough moves slowly eastward through the region, while a relatively
weak cold front moves slowly southeastward through our area on
Monday and Monday evening. The precipitation threat should shift
southeast of our forecast area by late Monday night as the upper
level trough shifts east of the region and a surface ridge
builds southeastward into the area behind the cold front.  Only
slight and short lived cooling is expected behind the cold front,
with pronounced warming expected Tuesday night and Wednesday as an
upper level ridge moves eastward into the region and southerly low
level flow returns and strengthens.  The GFS model increases the 850
mb temperatures to 12-16 degrees C by Wednesday night over our
forecast area, whle the ECMWF is not quite as warm.  The GFS model
brings convection into northeast MO and west central IL Wednesday
and Wednesday night due to strong low-mid level warm air advection
ahead of "ridge runner" type shortwaves.  There does seem to be some
convectve feedback in the GFS model at this time leading to
overamplified vort maxes and potentially too much convection
depicted by the model, although the ECMWF also has some qpf
extending south into this area as well.

GKS

&&

.AVIATION:  (For the 00z TAFs through 00z Friday Evening)
Issued at 610 PM CDT Thu Apr 17 2014

Cold front has settled into southern Missouri and Illinois. A band
of very light rain or sprinkles continues to advance northeast
immediately behind the front. The precipitation is struggling to
reach the ground due to the dry low levels of the atmosphere. Mid
level cloud deck will slowly move southeast, clearing the area
during Friday morning. Light north wind will become east.

Specifics for KSTL:

VFR conditions expected with light north wind becoming east.

CVKING

&&

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

$$

WFO LSX








000
FXUS63 KLSX 172010
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
310 PM CDT Thu Apr 17 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 306 PM CDT Thu Apr 17 2014

Despite cold front moving through region, front is weakening and
moisture is lacking so any precipitation will be very light in
nature. So just have slight chance of showers for portions of west
central/southwestern IL tonight. Otherwise, partly to mostly cloudy
skies to begin scattering out late tonight. Not a lot of caa with
this system, so lows will be in the mid 30s to mid 40s.

Byrd

.LONG TERM:  (Friday through Next Thursday)
Issued at 306 PM CDT Thu Apr 17 2014

Should have a clearing sky from northwest to southeast on Friday as
the surface ridge builds into the area behind the weakening cold
front, and as the upper level trough shifts east of our area.
Tranquil and warmer weather heading into the weekend as an upper
level ridge moves into the area on Saturday behind the upper level
trough/low.  Above normal high temperatures expected on Saturday and
Sunday as southerly surface/low level flow returns.  Low level
moisture and instability will increase over our area Saturday night
and Sunday due to the persistent southerly flow ahead of a slow
moving shortwave over the central Plains.  Scattered showers and a
few thundestorms will likely develop Sunday afternoon across MO, west
of STL.  Showers and a few storms should overspread our area Sunday
night and continue on Monday as this weakening shortwave/upper level
trough moves slowly eastward through the region, while a relatively
weak cold front moves slowly southeastward through our area on
Monday and Monday evening. The precipitation threat should shift
southeast of our forecast area by late Monday night as the upper
level trough shifts east of the region and a surface ridge
builds southeastward into the area behind the cold front.  Only
slight and short lived cooling is expected behind the cold front,
with pronounced warming expected Tuesday night and Wednesday as an
upper level ridge moves eastward into the region and southerly low
level flow returns and strengthens.  The GFS model increases the 850
mb temperatures to 12-16 degrees C by Wednesday night over our
forecast area, whle the ECMWF is not quite as warm.  The GFS model
brings convection into northeast MO and west central IL Wednesday
and Wednesday night due to strong low-mid level warm air advection
ahead of "ridge runner" type shortwaves.  There does seem to be some
convectve feedback in the GFS model at this time leading to
overamplified vort maxes and potentially too much convection
depicted by the model, although the ECMWF also has some qpf
extending south into this area as well.

GKS

&&

.AVIATION:  (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1249 PM CDT Thu Apr 17 2014

Weak cold front is making very slow progress to the south today.
It has moved through KUIN and KCOU, but is stalled over metro
area as of 17z. Mvfr cigs at KUIN have scattered out. Otherwise,
mid and high clouds prevail over region. As low level moisture
increases, just a bit, will see low end vfr cigs develop north of
frontal boundary late this afternoon and early this evening.
Shower activity will be very sparse so did not add mention to tafs
at this time. Otherwise, southwest winds to veer to the northwest
to north behind the boundary, but remain rather light. Later
tonight cigs to scatter out and winds become light and variable.
Winds will pickup just a bit from the northeast on Friday as
frontal boundary washes out and surface ridge builds in.

Specifics for KSTL:
Weak cold front is making very slow progress to the south today.
It has stalled over metro area as of 17z. Mid and high clouds
prevail over region. As low level moisture increases, just a bit,
will see low end vfr cigs develop north of frontal boundary after
03z Friday. Shower activity will be very sparse so did not add mention
to taf at this time. Otherwise, southwest winds to veer to the
north behind the boundary, but remain rather light. By 09z Friday
cigs to scatter out and winds become light and variable. Winds
will pickup just a bit from the northeast by 19z Friday as
frontal boundary washes out and surface ridge builds in.

Byrd

&&

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

$$

WFO LSX








000
FXUS63 KLSX 171749
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1249 PM CDT Thu Apr 17 2014

.SHORT TERM:  (Through Tonight)
Issued at 300 AM CDT Thu Apr 17 2014

A weak cold front will move into the area today and could serve as
the focus for scattered light rain showers during the afternoon
and evening. Convergence along the front is not very impressive
and the low levels are somewhat dry, but the combination of
increasing large scale ascent ahead of an approaching vort max
along with the presence of a surface boundary merits slight chance
to chance PoPs.

Kanofsky

.LONG TERM:  (Tomorrow through Wednesday)
Issued at 300 AM CDT Thu Apr 17 2014

For the last 4 nights in a row, no two consecutive 00z runs of the
ECMWF/GFS/GEM have had the same solution for upcoming frontal
systems, and there has also been a fair amount of variability
between models regarding the location of important features such as
upper vorticity maxima and surface boundaries. The latest runs keep
a strong vort max and its surface low up near the US/Canada border
on Fri night and Sat, therefore precipitation is no longer expected
with this system across the LSX CWA. The dominant feature for
Fri-Sat now appears to be ridging. Winds should eventually turn
southerly, bringing warmer air into the region for Sat and
reinforcing a baroclinic zone extending from the US/Canada system
as it starts to occlude. A broad trough moving through the desert
southwest could bring precipitation to the area on Sun/Mon. Chance
PoPs remain an acceptable compromise in light of the model
uncertainty. Confidence remains low in the forecast for this
weekend and beyond.

Kanofsky
&&

.AVIATION:  (For the 18z TAFs through 18z Friday Afternoon)
Issued at 1249 PM CDT Thu Apr 17 2014

Weak cold front is making very slow progress to the south today.
It has moved through KUIN and KCOU, but is stalled over metro
area as of 17z. Mvfr cigs at KUIN have scattered out. Otherwise,
mid and high clouds prevail over region. As low level moisture
increases, just a bit, will see low end vfr cigs develop north of
frontal boundary late this afternoon and early this evening.
Shower activity will be very sparse so did not add mention to tafs
at this time. Otherwise, southwest winds to veer to the northwest
to north behind the boundary, but remain rather light. Later
tonight cigs to scatter out and winds become light and variable.
Winds will pickup just a bit from the northeast on Friday as
frontal boundary washes out and surface ridge builds in.

Specifics for KSTL:
Weak cold front is making very slow progress to the south today.
It has stalled over metro area as of 17z. Mid and high clouds
prevail over region. As low level moisture increases, just a bit,
will see low end vfr cigs develop north of frontal boundary after
03z Friday. Shower activity will be very sparse so did not add mention
to taf at this time. Otherwise, southwest winds to veer to the
north behind the boundary, but remain rather light. By 09z Friday
cigs to scatter out and winds become light and variable. Winds
will pickup just a bit from the northeast by 19z Friday as
frontal boundary washes out and surface ridge builds in.

Byrd
&&

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

$$
WFO LSX







000
FXUS63 KLSX 171152
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
652 AM CDT Thu Apr 17 2014

.SHORT TERM:  (Through Tonight)
Issued at 300 AM CDT Thu Apr 17 2014

A weak cold front will move into the area today and could serve as
the focus for scattered light rain showers during the afternoon
and evening. Convergence along the front is not very impressive
and the low levels are somewhat dry, but the combination of
increasing large scale ascent ahead of an approaching vort max
along with the presence of a surface boundary merits slight chance
to chance PoPs.

Kanofsky

.LONG TERM:  (Tomorrow through Wednesday)
Issued at 300 AM CDT Thu Apr 17 2014

For the last 4 nights in a row, no two consecutive 00z runs of the
ECMWF/GFS/GEM have had the same solution for upcoming frontal
systems, and there has also been a fair amount of variability
between models regarding the location of important features such as
upper vorticity maxima and surface boundaries. The latest runs keep
a strong vort max and its surface low up near the US/Canada border
on Fri night and Sat, therefore precipitation is no longer expected
with this system across the LSX CWA. The dominant feature for
Fri-Sat now appears to be ridging. Winds should eventually turn
southerly, bringing warmer air into the region for Sat and
reinforcing a baroclinic zone extending from the US/Canada system
as it starts to occlude. A broad trough moving through the desert
southwest could bring precipitation to the area on Sun/Mon. Chance
PoPs remain an acceptable compromise in light of the model
uncertainty. Confidence remains low in the forecast for this
weekend and beyond.

Kanofsky

&&

.AVIATION:  (For the 12z TAFs through 12z Friday Morning)
Issued at 638 AM CDT Thu Apr 17 2014

Weak cold front currently on the door step of KCOU and KUIN will
drift east today, and not reach the STL metro area until 21-00z
time frame. Post frontal band of MVFR SC with bases 1-2kft has
worked into northern Missouri, and over the last few hours higher
clouds have obscured their movement on satellite imagery. However,
surface ob trends as well as RUC low level RH progs suggest that
this cloud deck will reach KUIN shortly, and then dissipate by
mid-late morning. With this expected trend, cloud deck should
remain n of KCOU, and not threaten STL area. Otherwise, cloud
trends today and into this evening should be dominated by a
thickening mid deck with bases aoa 5kft. We are expecting a few
post frontal showers, but given the hit and miss coverage that is
anticipated have not included in TAFS at this time.

Specifics for KSTL: Weak cold front currently over mid MO not
expected to reach the area until the 21-23z time frame, with winds
shifting slowly to the northwest once fropa occurs. Otherwise,
looking for a gradual increase in mid clouds over the area, with
bases remaining aoa 5kft. A few showers are possible in the
evening, but as mentioned in the primary aviation discussion have
omitted from this TAF set due to the spotty nature of the precip.

Truett

&&

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

$$

WFO LSX








000
FXUS63 KLSX 170811
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
311 AM CDT Thu Apr 17 2014

.SHORT TERM:  (Through Tonight)
Issued at 300 AM CDT Thu Apr 17 2014

A weak cold front will move into the area today and could serve as
the focus for scattered light rain showers during the afternoon
and evening. Convergence along the front is not very impressive
and the low levels are somewhat dry, but the combination of
increasing large scale ascent ahead of an approaching vort max
along with the presence of a surface boundary merits slight chance
to chance PoPs.

Kanofsky

.LONG TERM:  (Tomorrow through Wednesday)
Issued at 300 AM CDT Thu Apr 17 2014

For the last 4 nights in a row, no two consecutive 00z runs of the
ECMWF/GFS/GEM have had the same solution for upcoming frontal
systems, and there has also been a fair amount of variability
between models regarding the location of important features such as
upper vorticity maxima and surface boundaries. The latest runs keep
a strong vort max and its surface low up near the US/Canada border
on Fri night and Sat, therefore precipitation is no longer expected
with this system across the LSX CWA. The dominant feature for
Fri-Sat now appears to be ridging. Winds should eventually turn
southerly, bringing warmer air into the region for Sat and
reinforcing a baroclinic zone extending from the US/Canada system
as it starts to occlude. A broad trough moving through the desert
southwest could bring precipitation to the area on Sun/Mon. Chance
PoPs remain an acceptable compromise in light of the model
uncertainty. Confidence remains low in the forecast for this
weekend and beyond.

Kanofsky

&&

.AVIATION:  (For the 06z TAFs through 06z Thursday Night)
Issued at 1149 PM CDT Wed Apr 16 2014

Anticipate conditions will remain VFR despite a frontal passage
tomorrow morning. South wind will swing around to the northwest
with the front and then relax, becoming light and variable
Thursday evening. The lack of low level moisture keeps the
forecast dry at this time.

Specifics for KSTL:

VFR conditions with a south wind becoming southwest tomorrow
morning and then shifting to the northwest with the cold front
early tomorrow afternoon. Wind to become light and variable
tomorrow evening. VFR clouds possible behind the front, but
moisture looks limited, with a dry forecast continuing.

CVKING

&&

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

$$

WFO LSX








000
FXUS63 KLSX 170451
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1151 PM CDT Wed Apr 16 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 233 PM CDT Wed Apr 16 2014

A rather tranquil night is on tap for the area. The surface low
currently in extreme northwest Iowa will move northeastward tonight
and into Wisconsin by daybreak, with the attendant cold front
stretching from northeast MO into west central MO at 12Z. As a
result the surface pressure gradient will weaken this evening. This
along with an end to deep mixing around sunset will result in
quickly diminishing southerly surface winds. Surface winds do remain
southerly all night but due to extensive lower tropospheric ridging
well into the GOM, low level moisture return will be nil and limited
to an increase in mid-hi level moisture. The associated cloudiness
and southerly winds will keep temperatures warmer than last night.

Glass

.LONG TERM:  (Thursday through Next Wednesday)
Issued at 322 PM CDT Wed Apr 16 2014

A weak cold front will move southeastward through our forecast area
Thursday and Thursday night.  The models depict upper level
divergence over our area Thursday and Thursday evening ahead of an
approaching upper level trough.  Moisture and instability will be
limited with this front, but there should still be scattered showers
along and just behind this front Thursday afternoon and night.  The
threat for showers should end Friday morning with a clearing sky as
the upper level trough moves east of the region.  Only slight
cooling is expected behind the front, mainly across northeast MO and
west central IL Thursday afternoon and night.  Temperatures will
warm back up Friday and Friday night as the upper level heights rise
as the upper level trough moves east of our area and as upper level
ridging centered over the southern Plains moves into our area.  Much
warmer, above normal high temperatures are expected on Saturday as
southerly surface/low level flow returns.  The chance of showers
will return to our area Sunday and continue through Monday as a
shortwave approaches and a weak cold front moves southeastward
through our area Sunday night and Monday.  It appears that there
will be more favorable level low moisture and instability present
with this weak front than the front which will move through our area
Thursday and Thursday night and hence a greater threat for showers
and possibly also thunderstorms.  Ony short lived, slight cooling
expected behind this front, then pronounced warming for Wednesday
with an upper level ridge over the region and strengthening sly/swly
surface/low level flow.  The models are forecasting 850 mb
temperatures rising to around 12-16 degrees C by 00z Thursday.

GKS

&&

.AVIATION:  (For the 06z TAFs through 06z Thursday Night)
Issued at 1149 PM CDT Wed Apr 16 2014

Anticipate conditions will remain VFR despite a frontal passage
tomorrow morning. South wind will swing around to the northwest
with the front and then relax, becoming light and variable
Thursday evening. The lack of low level moisture keeps the
forecast dry at this time.

Specifics for KSTL:

VFR conditions with a south wind becoming southwest tomorrow
morning and then shifting to the northwest with the cold front
early tomorrow afternoon. Wind to become light and variable
tomorrow evening. VFR clouds possible behind the front, but
moisture looks limited, with a dry forecast continuing.

CVKING

&&

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

$$

WFO LSX








000
FXUS63 KLSX 162346
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
646 PM CDT Wed Apr 16 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 233 PM CDT Wed Apr 16 2014

A rather tranquil night is on tap for the area. The surface low
currently in extreme northwest Iowa will move northeastward tonight
and into Wisconsin by daybreak, with the attendant cold front
stretching from northeast MO into west central MO at 12Z. As a
result the surface pressure gradient will weaken this evening. This
along with an end to deep mixing around sunset will result in
quickly diminishing southerly surface winds. Surface winds do remain
southerly all night but due to extensive lower tropospheric ridging
well into the GOM, low level moisture return will be nil and limited
to an increase in mid-hi level moisture. The associated cloudiness
and southerly winds will keep temperatures warmer than last night.

Glass

.LONG TERM:  (Thursday through Next Wednesday)
Issued at 322 PM CDT Wed Apr 16 2014

A weak cold front will move southeastward through our forecast area
Thursday and Thursday night.  The models depict upper level
divergence over our area Thursday and Thursday evening ahead of an
approaching upper level trough.  Moisture and instability will be
limited with this front, but there should still be scattered showers
along and just behind this front Thursday afternoon and night.  The
threat for showers should end Friday morning with a clearing sky as
the upper level trough moves east of the region.  Only slight
cooling is expected behind the front, mainly across northeast MO and
west central IL Thursday afternoon and night.  Temperatures will
warm back up Friday and Friday night as the upper level heights rise
as the upper level trough moves east of our area and as upper level
ridging centered over the southern Plains moves into our area.  Much
warmer, above normal high temperatures are expected on Saturday as
southerly surface/low level flow returns.  The chance of showers
will return to our area Sunday and continue through Monday as a
shortwave approaches and a weak cold front moves southeastward
through our area Sunday night and Monday.  It appears that there
will be more favorable level low moisture and instability present
with this weak front than the front which will move through our area
Thursday and Thursday night and hence a greater threat for showers
and possibly also thunderstorms.  Ony short lived, slight cooling
expected behind this front, then pronounced warming for Wednesday
with an upper level ridge over the region and strengthening sly/swly
surface/low level flow.  The models are forecasting 850 mb
temperatures rising to around 12-16 degrees C by 00z Thursday.

GKS

&&

.AVIATION:  (For the 00z TAFs through 00z Thursday Evening)
Issued at 642 PM CDT Wed Apr 16 2014

VFR conditions expected. Strong and gusty south wind will relax
and back to the south/southeast this evening. Cold front expected
to move across the region Thursday morning with a wind shift to
the west. Wind to become light and variable Thursday evening.
Confidence in any measurable precipitation is too low at this time
to include in the forecast.

Specifics for KSTL:
VFR conditions expected. Cold front expected to move across the
area late Thursday morning with winds shifting to the west in the
afternoon and then becoming light and variable Thursday evening as
the front settles to the south of the terminal.

CVKING

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...RED FLAG WARNING until 7 PM CDT this evening FOR Audrain MO-
     Boone MO-Callaway MO-Cole MO-Franklin MO-Gasconade MO-
     Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Marion MO-Moniteau
     MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby
     MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO.

IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 162024
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
324 PM CDT Wed Apr 16 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 233 PM CDT Wed Apr 16 2014

A rather tranquil night is on tap for the area. The surface low
currently in extreme northwest Iowa will move northeastward tonight
and into Wisconsin by daybreak, with the attendant cold front
stretching from northeast MO into west central MO at 12Z. As a
result the surface pressure gradient will weaken this evening. This
along with an end to deep mixing around sunset will result in
quickly diminishing southerly surface winds. Surface winds do remain
southerly all night but due to extensive lower tropospheric ridging
well into the GOM, low level moisture return will be nil and limited
to an increase in mid-hi level moisture. The associated cloudiness
and southerly winds will keep temperatures warmer than last night.

Glass

.LONG TERM:  (Thursday through Next Wednesday)
Issued at 322 PM CDT Wed Apr 16 2014

A weak cold front will move southeastward through our forecast area
Thursday and Thursday night.  The models depict upper level
divergence over our area Thursday and Thursday evening ahead of an
approaching upper level trough.  Moisture and instability will be
limited with this front, but there should still be scattered showers
along and just behind this front Thursday afternoon and night.  The
threat for showers should end Friday morning with a clearing sky as
the upper level trough moves east of the region.  Only slight
cooling is expected behind the front, mainly across northeast MO and
west central IL Thursday afternoon and night.  Temperatures will
warm back up Friday and Friday night as the upper level heights rise
as the upper level trough moves east of our area and as upper level
ridging centered over the southern Plains moves into our area.  Much
warmer, above normal high temperatures are expected on Saturday as
southerly surface/low level flow returns.  The chance of showers
will return to our area Sunday and continue through Monday as a
shortwave approaches and a weak cold front moves southeastward
through our area Sunday night and Monday.  It appears that there
will be more favorable level low moisture and instability present
with this weak front than the front which will move through our area
Thursday and Thursday night and hence a greater threat for showers
and possibly also thunderstorms.  Ony short lived, slight cooling
expected behind this front, then pronounced warming for Wednesday
with an upper level ridge over the region and strengthening sly/swly
surface/low level flow.  The models are forecasting 850 mb
temperatures rising to around 12-16 degrees C by 00z Thursday.

GKS

&&

.AVIATION:  (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1219 PM CDT Wed Apr 16 2014

The main element to contend with will be surface winds. Southerly
winds will gust to 25+ kts this afternoon, diminishing around
sunset. The wind will slowly and gradually veer to more south
southwesterly during the late night and early morning hours on
Thursday with a wind shift to the west as a weak cold front slowly
pushes across the region. VFR flight conditions will prevail
through the forecast period. Any chance of showers will be beyond
the valid TAF period - Thursday afternoon and evening.

Specifics for KSTL:

The main element to contend with will be surface winds. Southerly
winds will gust to 25+ kts this afternoon, diminishing around sunset.
The wind will slowly and gradually veer to more south southwesterly
on Thursday morning with a wind shift to the west in the mid-late
afternoon associated with passage of a weak cold front. VFR flight
conditions will prevail through the forecast period. Any chance of
showers will be beyond the valid TAF period - Thursday evening.

Glass

&&

.FIRE WEATHER:
Issued at 233 PM CDT Wed Apr 16 2014

20 foot winds are strong and gusty. 10 hour fuel moisture and
relative humidity thus far this afternoon has remained above
criteria for red flag conditions. There are still 2-3 hours left
of potential and I expect that fuel moisture will fall below 9%
and RH will likewise dip at or below 25% in at least parts of the
warning area. Thus we will keep the Red Flag Warning going through
700 pm as scheduled. Conditions will be improved on Thursday with
lighter winds and slightly more moisture along with a cold frontal
passage.

Glass


&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...RED FLAG WARNING until 7 PM CDT this evening FOR Audrain MO-
     Boone MO-Callaway MO-Cole MO-Franklin MO-Gasconade MO-
     Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Marion MO-Moniteau
     MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby
     MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO.

IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 161941
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
241 PM CDT Wed Apr 16 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 233 PM CDT Wed Apr 16 2014

A rather tranquil night is on tap for the area. The surface low
currently in extreme northwest Iowa will move northeastward tonight
and into Wisconsin by daybreak, with the attendant cold front
stretching from northeast MO into west central MO at 12Z. As a
result the surface pressure gradient will weaken this evening. This
along with an end to deep mixing around sunset will result in
quickly diminishing southerly surface winds. Surface winds do remain
southerly all night but due to extensive lower tropospheric ridging
well into the GOM, low level moisture return will be nil and limited
to an increase in mid-hi level moisture. The associated cloudiness
and southerly winds will keep temperatures warmer than last night.

Glass

.LONG TERM: (Tonight through Tuesday)
Issued at 315 AM CDT Wed Apr 16 2014

Surface low and upper vort max move through IA into WI tonight,
leaving a trailing cold front stretching from WI into northern MO
and central KS. The wind shift and temperature contrast across the
boundary are not terribly impressive tomorrow, but with a vort max
forecast to approach and move across the area, the boundary could
provide a focus for SHRA during the afternoon and evening.
Instability parameters look weak therefore kept thunder out of the
forecast.

It`s not clear whether the aforementioned boundary washes out in
place or sinks a bit farther south tomorrow night, but a new warm
front should develop somewhere in the region on Fri/Sat as another
surface low develops to the west in response to an approaching
upper vort max. ECMWF/GEM/GFS all show different orientations for
the warm front which extends from a surface low over SD/ND, CO, or
both depending on which model and which run. Over the last couple
of days, the model solutions for Fri-Mon have varied quite a bit
compared to their previous runs (particularly with regards to the
location of surface synoptic systems and the placement of upper
vorts), and tonight`s runs are no exception. Since the models seem
fairly insistent that some kind of low pressure system ought to
affect this part of the country late in the weekend or early next
week, chance PoPs for Sun/Mon look like an acceptable compromise
in light of the model uncertainty.

Kanofsky

&&

.AVIATION:  (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1219 PM CDT Wed Apr 16 2014

The main element to contend with will be surface winds. Southerly
winds will gust to 25+ kts this afternoon, diminishing around
sunset. The wind will slowly and gradually veer to more south
southwesterly during the late night and early morning hours on
Thursday with a wind shift to the west as a weak cold front slowly
pushes across the region. VFR flight conditions will prevail
through the forecast period. Any chance of showers will be beyond
the valid TAF period - Thursday afternoon and evening.

Specifics for KSTL:

The main element to contend with will be surface winds. Southerly
winds will gust to 25+ kts this afternoon, diminishing around sunset.
The wind will slowly and gradually veer to more south southwesterly
on Thursday morning with a wind shift to the west in the mid-late
afternoon associated with passage of a weak cold front. VFR flight
conditions will prevail through the forecast period. Any chance of
showers will be beyond the valid TAF period - Thursday evening.

Glass

&&

.FIRE WEATHER:
Issued at 233 PM CDT Wed Apr 16 2014

20 foot winds are strong and gusty. 10 hour fuel moisture and
relative humidity thus far this afternoon has remained above
criteria for red flag conditions. There are still 2-3 hours left
of potential and I expect that fuel moisture will fall below 9%
and RH will likewise dip at or below 25% in at least parts of the
warning area. Thus we will keep the Red Flag Warning going through
700 pm as scheduled. Conditions will be improved on Thursday with
lighter winds and slightly more moisture along with a cold frontal
passage.

Glass

&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...RED FLAG WARNING until 7 PM CDT this evening FOR Audrain MO-
     Boone MO-Callaway MO-Cole MO-Franklin MO-Gasconade MO-
     Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Marion MO-Moniteau
     MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby
     MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO.

IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 161728
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1228 PM CDT Wed Apr 16 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 315 AM CDT Wed Apr 16 2014

Surface temperatures at 08z across the ongoing Freeze Warning
remained in the mid to upper 30s. With increasing winds for the
remainder of the night and only a few hours left until sunrise, it
does not look like temperatures will remain at or below freezing for
any appreciable length of time, therefore the Freeze Warning will be
canceled with the morning package.

Expect warm and dry weather today with highs in the upper 50s to mid
60s, but the tightening pressure gradient ahead of a surface low
over NE/SD will lead to windy conditions, especially during the
afternoon. At this time, the forecast winds do not meet LSX criteria
for a Wind Advisory (sustained winds of 30-39 mph/26-34 kt and/or
gusts of 45-57 mph/39-49 kts), therefore no wind headlines are
planned. If the actual winds today end up being stronger than
currently forecast, then a Wind Advisory may eventually be needed,
especially for parts of central/northern MO where the gradient will
be tightest.

The combination of strong and gusty winds, low RH, and low fuel
moisture values will produce Red Flag Warning conditions across
parts of the area. Please see the fire weather section below for
additional details.

Kanofsky

.LONG TERM:  (Tonight through Tuesday)
Issued at 315 AM CDT Wed Apr 16 2014

Surface low and upper vort max move through IA into WI tonight,
leaving a trailing cold front stretching from WI into northern MO
and central KS. The wind shift and temperature contrast across the
boundary are not terribly impressive tomorrow, but with a vort max
forecast to approach and move across the area, the boundary could
provide a focus for SHRA during the afternoon and evening.
Instability parameters look weak therefore kept thunder out of the
forecast.

It`s not clear whether the aforementioned boundary washes out in
place or sinks a bit farther south tomorrow night, but a new warm
front should develop somewhere in the region on Fri/Sat as another
surface low develops to the west in response to an approaching
upper vort max. ECMWF/GEM/GFS all show different orientations for
the warm front which extends from a surface low over SD/ND, CO, or
both depending on which model and which run. Over the last couple
of days, the model solutions for Fri-Mon have varied quite a bit
compared to their previous runs (particularly with regards to the
location of surface synoptic systems and the placement of upper
vorts), and tonight`s runs are no exception. Since the models seem
fairly insistent that some kind of low pressure system ought to
affect this part of the country late in the weekend or early next
week, chance PoPs for Sun/Mon look like an acceptable compromise
in light of the model uncertainty.

Kanofsky

&&

.AVIATION:  (For the 18z TAFs through 18z Thursday Afternoon)
Issued at 1219 PM CDT Wed Apr 16 2014

The main element to contend with will be surface winds. Southerly
winds will gust to 25+ kts this afternoon, diminishing around
sunset. The wind will slowly and gradually veer to more south
southwesterly during the late night and early morning hours on
Thursday with a wind shift to the west as a weak cold front slowly
pushes across the region. VFR flight conditions will prevail
through the forecast period. Any chance of showers will be beyond
the valid TAF period - Thursday afternoon and evening.

Specifics for KSTL:

The main element to contend with will be surface winds. Southerly
winds will gust to 25+ kts this afternoon, diminishing around sunset.
The wind will slowly and gradually veer to more south southwesterly
on Thursday morning with a wind shift to the west in the mid-late
afternoon associated with passage of a weak cold front. VFR flight
conditions will prevail through the forecast period. Any chance of
showers will be beyond the valid TAF period - Thursday evening.

Glass

&&

.FIRE WEATHER:
Issued at 315 AM CDT Wed Apr 16 2014

Red Flag Warning conditions are expected for parts of central,
eastern, and northeastern MO today with a heightened fire danger
elsewhere. The WFAS forecast of 10hr fuel moisture for this area
is 7-8% for today. Southerly winds will increase during the
morning hours and remain gusty through the afternoon. Expect
sustained winds of around 20 mph gusting to around 30 mph,
possibly higher at times. Minimum afternoon relative humidity
values should fall to 20-30% with the lowest values across parts
of central and northern MO. Since RFW criteria for wind and fuel
moisture will be met nearly everywhere this afternoon, the area
covered by the RFW is based on a forecast of where minimum RH
values are expected to fall below 25%. Depending on dew point and
temperature trends, the RFW might need to be expanded today.

Kanofsky


&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...RED FLAG WARNING until 7 PM CDT this evening FOR Audrain MO-
     Boone MO-Callaway MO-Cole MO-Franklin MO-Gasconade MO-
     Jefferson MO-Knox MO-Lewis MO-Lincoln MO-Marion MO-Moniteau
     MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby
     MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO.

IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 161144
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
644 AM CDT Wed Apr 16 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 315 AM CDT Wed Apr 16 2014

Surface temperatures at 08z across the ongoing Freeze Warning
remained in the mid to upper 30s. With increasing winds for the
remainder of the night and only a few hours left until sunrise, it
does not look like temperatures will remain at or below freezing for
any appreciable length of time, therefore the Freeze Warning will be
canceled with the morning package.

Expect warm and dry weather today with highs in the upper 50s to mid
60s, but the tightening pressure gradient ahead of a surface low
over NE/SD will lead to windy conditions, especially during the
afternoon. At this time, the forecast winds do not meet LSX criteria
for a Wind Advisory (sustained winds of 30-39 mph/26-34 kt and/or
gusts of 45-57 mph/39-49 kts), therefore no wind headlines are
planned. If the actual winds today end up being stronger than
currently forecast, then a Wind Advisory may eventually be needed,
especially for parts of central/northern MO where the gradient will
be tightest.

The combination of strong and gusty winds, low RH, and low fuel
moisture values will produce Red Flag Warning conditions across
parts of the area. Please see the fire weather section below for
additional details.

Kanofsky

.LONG TERM:  (Tonight through Tuesday)
Issued at 315 AM CDT Wed Apr 16 2014

Surface low and upper vort max move through IA into WI tonight,
leaving a trailing cold front stretching from WI into northern MO
and central KS. The wind shift and temperature contrast across the
boundary are not terribly impressive tomorrow, but with a vort max
forecast to approach and move across the area, the boundary could
provide a focus for SHRA during the afternoon and evening.
Instability parameters look weak therefore kept thunder out of the
forecast.

It`s not clear whether the aforementioned boundary washes out in
place or sinks a bit farther south tomorrow night, but a new warm
front should develop somewhere in the region on Fri/Sat as another
surface low develops to the west in response to an approaching
upper vort max. ECMWF/GEM/GFS all show different orientations for
the warm front which extends from a surface low over SD/ND, CO, or
both depending on which model and which run. Over the last couple
of days, the model solutions for Fri-Mon have varied quite a bit
compared to their previous runs (particularly with regards to the
location of surface synoptic systems and the placement of upper
vorts), and tonight`s runs are no exception. Since the models seem
fairly insistent that some kind of low pressure system ought to
affect this part of the country late in the weekend or early next
week, chance PoPs for Sun/Mon look like an acceptable compromise
in light of the model uncertainty.

Kanofsky

&&

.AVIATION:  (For the 12z TAFs through 12z Thursday Morning)
Issued at 645 AM CDT Wed Apr 16 2014

Strong south winds will be the primary aviation weather concern
today. Forecast soundings as well as MOS guidance indicate a rapid
jump in wind speeds between 14-16z, with highest sustained winds
of 20-25kts and occasional gusts to around 30 kts at KUIN and
KCOU from late morning into the afternoon. It also appears winds
will diminish fairly rapidly in the 23z-02z time frame...with
speeds of 5-10kts throughout the late evening and overnight.
Otherwise, no significant clouds or precipitation expected during
this TAF period.

Specifics for KSTL: South winds will pick up fairly rapidly in the
13-16z time frame, with sustained winds of 15-20kts and gusts
to 25kts from the late morning and throughout the afternoon, then dropping
back off to around 10kts shortly after sunset. Clouds will be
limited to some high level cirrus through tonight.

Truett

&&

.FIRE WEATHER:
Issued at 315 AM CDT Wed Apr 16 2014

Red Flag Warning conditions are expected for parts of central,
eastern, and northeastern MO today with a heightened fire danger
elsewhere. The WFAS forecast of 10hr fuel moisture for this area
is 7-8% for today. Southerly winds will increase during the
morning hours and remain gusty through the afternoon. Expect
sustained winds of around 20 mph gusting to around 30 mph,
possibly higher at times. Minimum afternoon relative humidity
values should fall to 20-30% with the lowest values across parts
of central and northern MO. Since RFW criteria for wind and fuel
moisture will be met nearly everywhere this afternoon, the area
covered by the RFW is based on a forecast of where minimum RH
values are expected to fall below 25%. Depending on dew point and
temperature trends, the RFW might need to be expanded today.

Kanofsky


&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...RED FLAG WARNING from 11 AM this morning to 7 PM CDT this
     evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-
     Franklin MO-Gasconade MO-Jefferson MO-Knox MO-Lewis MO-
     Lincoln MO-Marion MO-Moniteau MO-Monroe MO-Montgomery MO-
     Osage MO-Pike MO-Ralls MO-Shelby MO-St. Charles MO-St.
     Louis City MO-St. Louis MO-Warren MO.

IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 160833
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
333 AM CDT Wed Apr 16 2014

.SHORT TERM:  (Through Late This Afternoon)
Issued at 315 AM CDT Wed Apr 16 2014

Surface temperatures at 08z across the ongoing Freeze Warning
remained in the mid to upper 30s. With increasing winds for the
remainder of the night and only a few hours left until sunrise, it
does not look like temperatures will remain at or below freezing for
any appreciable length of time, therefore the Freeze Warning will be
canceled with the morning package.

Expect warm and dry weather today with highs in the upper 50s to mid
60s, but the tightening pressure gradient ahead of a surface low
over NE/SD will lead to windy conditions, especially during the
afternoon. At this time, the forecast winds do not meet LSX criteria
for a Wind Advisory (sustained winds of 30-39 mph/26-34 kt and/or
gusts of 45-57 mph/39-49 kts), therefore no wind headlines are
planned. If the actual winds today end up being stronger than
currently forecast, then a Wind Advisory may eventually be needed,
especially for parts of central/northern MO where the gradient will
be tightest.

The combination of strong and gusty winds, low RH, and low fuel
moisture values will produce Red Flag Warning conditions across
parts of the area. Please see the fire weather section below for
additional details.

Kanofsky

.LONG TERM:  (Tonight through Tuesday)
Issued at 315 AM CDT Wed Apr 16 2014

Surface low and upper vort max move through IA into WI tonight,
leaving a trailing cold front stretching from WI into northern MO
and central KS. The wind shift and temperature contrast across the
boundary are not terribly impressive tomorrow, but with a vort max
forecast to approach and move across the area, the boundary could
provide a focus for SHRA during the afternoon and evening.
Instability parameters look weak therefore kept thunder out of the
forecast.

It`s not clear whether the aforementioned boundary washes out in
place or sinks a bit farther south tomorrow night, but a new warm
front should develop somewhere in the region on Fri/Sat as another
surface low develops to the west in response to an approaching
upper vort max. ECMWF/GEM/GFS all show different orientations for
the warm front which extends from a surface low over SD/ND, CO, or
both depending on which model and which run. Over the last couple
of days, the model solutions for Fri-Mon have varied quite a bit
compared to their previous runs (particularly with regards to the
location of surface synoptic systems and the placement of upper
vorts), and tonight`s runs are no exception. Since the models seem
fairly insistent that some kind of low pressure system ought to
affect this part of the country late in the weekend or early next
week, chance PoPs for Sun/Mon look like an acceptable compromise
in light of the model uncertainty.

Kanofsky

&&

.AVIATION:  (For the 06z TAFs through 06z Wednesday Night)
Issued at 1142 PM CDT Tue Apr 15 2014

VFR. South wind to rapidly increase on Wednesday morning with
sustained wind speeds of 20KT and gusts to 30KT.

Specifics for KSTL:
VFR. South wind to rapidly increase on Wednesday morning with
sustained wind speeds of 20KT and gusts to 30KT.

CVKING

&&

.FIRE WEATHER:
Issued at 315 AM CDT Wed Apr 16 2014

Red Flag Warning conditions are expected for parts of central,
eastern, and northeastern MO today with a heightened fire danger
elsewhere. The WFAS forecast of 10hr fuel moisture for this area
is 7-8% for today. Southerly winds will increase during the
morning hours and remain gusty through the afternoon. Expect
sustained winds of around 20 mph gusting to around 30 mph,
possibly higher at times. Minimum afternoon relative humidity
values should fall to 20-30% with the lowest values across parts
of central and northern MO. Since RFW criteria for wind and fuel
moisture will be met nearly everywhere this afternoon, the area
covered by the RFW is based on a forecast of where minimum RH
values are expected to fall below 25%. Depending on dew point and
temperature trends, the RFW might need to be expanded today.

Kanofsky


&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...RED FLAG WARNING from 11 AM this morning to 7 PM CDT this
     evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-
     Franklin MO-Gasconade MO-Jefferson MO-Knox MO-Lewis MO-
     Lincoln MO-Marion MO-Moniteau MO-Monroe MO-Montgomery MO-
     Osage MO-Pike MO-Ralls MO-Shelby MO-St. Charles MO-St.
     Louis City MO-St. Louis MO-Warren MO.

IL...NONE.
&&

$$

WFO LSX








000
FXUS63 KLSX 160444
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1144 PM CDT Tue Apr 15 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 357 PM CDT Tue Apr 15 2014

Another cool night is on tap tonight across the area, with
temperatures expected to range from around 30 degrees across
southeastern Missouri and southwest Illinois to the mid 30s over
central Missouri and in the St. Louis metropolitan area.  The main
concern overnight is once again frost/freeze headlines. As the ridge
axis shifts toward the Ohio Valley, winds will shift to the south in
its wake, and increased southerly flow and warmer temperatures will
preclude any widespread frost over zones further north and west.
However, over southeastern and eastern zones, where calm to light
south winds are anticipated as the ridge axis moves through that
area, along with our coolest temperatures of the night, have gone
ahead and replaced the inherited Frost Advisory with a Freeze
Warning, and expanded it by 3 counties in Illinois where subfreezing
temperatures are anticipated.

JP

.LONG TERM: (Wednesday through Next Tuesday)
Issued at 357 PM CDT Tue Apr 15 2014

(Wednesday through Friday)

Still expecting dry weather through early Thursday before a cold
front enters northeast Missouri and moves southeast across the CWA
on Thursday night.   Moisture convergence along the front is
somewhat limited along the front so have chance pops starting
Thursday afternoon over northeast Missouri.  Then have chance pops
across the entire area on Thursday night as large scale ascent
increases ahead of the mid-level trough.  This trough will move east
of the area by Friday, so have dropped POPs to slight chances during
the day.

After the cool start tomorrow morning, temperatures will be about 10
degrees warmer tomorrow than today.  Temperatures will also be
slightly warmer ahead of the cold front on Thursday ahead of the
cold front.

(Saturday through next Tuesday)

Will keep Saturday dry as both the GFS/ECMWF show an upper ridge
moving across the area.  Will keep chance of showers going Saturday
night into Sunday night as both models show a mid level trough and a
attendant surface front moving through the area.  Subsidence will
build in behind the trough and both models are showing that an upper
ridge will build into the area for the middle of next week with
temperatures starting to warm up above normal as early as next
Tuesday.


Britt

&&

.AVIATION:  (For the 06z TAFs through 06z Wednesday Night)
Issued at 1142 PM CDT Tue Apr 15 2014

VFR. South wind to rapidly increase on Wednesday morning with
sustained wind speeds of 20KT and gusts to 30KT.

Specifics for KSTL:
VFR. South wind to rapidly increase on Wednesday morning with
sustained wind speeds of 20KT and gusts to 30KT.

CVKING

&&

.FIRE WEATHER:
Issued at 357 PM CDT Tue Apr 15 2014

Will be issuing a fire weather watch for Wednesday afternoon for a
small part of central and northeast Missouri. Model dewpoints are
too high based on recent trends and upstream dewpoints over the
central and southern Plains. Expected RH values tomorrow will be
in the lower 20s with southerly winds of 15 to 25 mph with higher
gusts.  These values along with 10 hour dry fuels falling below 9
percent warrant issuing a fire weather watch tomorrow.

Britt/JP


&&

.CLIMATE:

RECORD LOWS FOR 4/15:

STL - 27 IN 1928
COU - 25 IN 1928
UIN - 24 IN 1928
FAM - 24 IN 1928


&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FREEZE WARNING until 9 AM CDT Wednesday FOR Crawford MO-Iron MO-
     Jefferson MO-Madison MO-Reynolds MO-St. Francois MO-Ste.
     Genevieve MO-Washington MO.

     FIRE WEATHER WATCH from 11 AM CDT Wednesday through Wednesday
     evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Knox MO-
     Moniteau MO-Monroe MO-Shelby MO.

IL...FREEZE WARNING until 9 AM CDT Wednesday FOR Bond IL-Clinton IL-
     Fayette IL-Marion IL-Monroe IL-Montgomery IL-Randolph IL-
     St. Clair IL-Washington IL.

&&

$$

WFO LSX








000
FXUS63 KLSX 152212
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
512 PM CDT Tue Apr 15 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 357 PM CDT Tue Apr 15 2014

Another cool night is on tap tonight across the area, with
temperatures expected to range from around 30 degrees across
southeastern Missouri and southwest Illinois to the mid 30s over
central Missouri and in the St. Louis metropolitan area.  The main
concern overnight is once again frost/freeze headlines. As the ridge
axis shifts toward the Ohio Valley, winds will shift to the south in
its wake, and increased southerly flow and warmer temperatures will
preclude any widespread frost over zones further north and west.
However, over southeastern and eastern zones, where calm to light
south winds are anticipated as the ridge axis moves through that
area, along with our coolest temperatures of the night, have gone
ahead and replaced the inherited Frost Advisory with a Freeze
Warning, and expanded it by 3 counties in Illinois where subfreezing
temperatures are anticipated.

JP

.LONG TERM: (Wednesday through Next Tuesday)
Issued at 357 PM CDT Tue Apr 15 2014

(Wednesday through Friday)

Still expecting dry weather through early Thursday before a cold
front enters northeast Missouri and moves southeast across the CWA
on Thursday night.   Moisture convergence along the front is
somewhat limited along the front so have chance pops starting
Thursday afternoon over northeast Missouri.  Then have chance pops
across the entire area on Thursday night as large scale ascent
increases ahead of the mid-level trough.  This trough will move east
of the area by Friday, so have dropped POPs to slight chances during
the day.

After the cool start tomorrow morning, temperatures will be about 10
degrees warmer tomorrow than today.  Temperatures will also be
slightly warmer ahead of the cold front on Thursday ahead of the
cold front.

(Saturday through next Tuesday)

Will keep Saturday dry as both the GFS/ECMWF show an upper ridge
moving across the area.  Will keep chance of showers going Saturday
night into Sunday night as both models show a mid level trough and a
attendant surface front moving through the area.  Subsidence will
build in behind the trough and both models are showing that an upper
ridge will build into the area for the middle of next week with
temperatures starting to warm up above normal as early as next
Tuesday.


Britt

&&

.AVIATION:  (For the 00z TAFs through 00z Wednesday Evening)
Issued at 509 PM CDT Tue Apr 15 2014

VFR conditions. Surface ridge of high pressure will move east
with wind increasing out of the south, especially on Wednesday.
Sustained wind of 20KT with gusts to 30KT expected.

Specifics for KSTL:
VFR conditions. South wind increasing, especially Wednesday with
wind of 20KT and gusts to 30 KT.

CVKING

&&

.FIRE WEATHER:
Issued at 357 PM CDT Tue Apr 15 2014

Will be issuing a fire weather watch for Wednesday afternoon for a
small part of central and northeast Missouri. Model dewpoints are
too high based on recent trends and upstream dewpoints over the
central and southern Plains. Expected RH values tomorrow will be
in the lower 20s with southerly winds of 15 to 25 mph with higher
gusts.  These values along with 10 hour dry fuels falling below 9
percent warrant issuing a fire weather watch tomorrow.

Britt/JP


&&

.CLIMATE:

RECORD LOWS FOR 4/15:

STL - 27 IN 1928
COU - 25 IN 1928
UIN - 24 IN 1928
FAM - 24 IN 1928


&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FREEZE WARNING from 1 AM to 9 AM CDT Wednesday FOR Crawford MO-
     Iron MO-Jefferson MO-Madison MO-Reynolds MO-St. Francois MO-
     Ste. Genevieve MO-Washington MO.

     FIRE WEATHER WATCH from Wednesday morning through Wednesday
     evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Knox MO-
     Moniteau MO-Monroe MO-Shelby MO.

IL...FREEZE WARNING from 1 AM to 9 AM CDT Wednesday FOR Bond IL-
     Clinton IL-Fayette IL-Marion IL-Monroe IL-Montgomery IL-
     Randolph IL-St. Clair IL-Washington IL.

&&

$$

WFO LSX








000
FXUS63 KLSX 152104
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
404 PM CDT Tue Apr 15 2014

.SHORT TERM:  (Through Late Tonight)
Issued at 357 PM CDT Tue Apr 15 2014

Another cool night is on tap tonight across the area, with
temperatures expected to range from around 30 degrees across
southeastern Missouri and southwest Illinois to the mid 30s over
central Missouri and in the St. Louis metropolitan area.  The main
concern overnight is once again frost/freeze headlines. As the ridge
axis shifts toward the Ohio Valley, winds will shift to the south in
its wake, and increased southerly flow and warmer temperatures will
preclude any widespread frost over zones further north and west.
However, over southeastern and eastern zones, where calm to light
south winds are anticipated as the ridge axis moves through that
area, along with our coolest temperatures of the night, have gone
ahead and replaced the inherited Frost Advisory with a Freeze
Warning, and expanded it by 3 counties in Illinois where subfreezing
temperatures are anticipated.

JP

.LONG TERM: (Wednesday through Next Tuesday)
Issued at 357 PM CDT Tue Apr 15 2014

(Wednesday through Friday)

Still expecting dry weather through early Thursday before a cold
front enters northeast Missouri and moves southeast across the CWA
on Thursday night.   Moisture convergence along the front is
somewhat limited along the front so have chance pops starting
Thursday afternoon over northeast Missouri.  Then have chance pops
across the entire area on Thursday night as large scale ascent
increases ahead of the mid-level trough.  This trough will move east
of the area by Friday, so have dropped POPs to slight chances during
the day.

After the cool start tomorrow morning, temperatures will be about 10
degrees warmer tomorrow than today.  Temperatures will also be
slightly warmer ahead of the cold front on Thursday ahead of the
cold front.

(Saturday through next Tuesday)

Will keep Saturday dry as both the GFS/ECMWF show an upper ridge
moving across the area.  Will keep chance of showers going Saturday
night into Sunday night as both models show a mid level trough and a
attendant surface front moving through the area.  Subsidence will
build in behind the trough and both models are showing that an upper
ridge will build into the area for the middle of next week with
temperatures starting to warm up above normal as early as next
Tuesday.


Britt

&&

.AVIATION:  (For the 18z TAFs through 18z Wednesday Afternoon)
Issued at 1237 PM CDT Tue Apr 15 2014

Dry, VFR conditions will prevail for the forecast period. West-
northwest winds today will become light/variable as the surface
ridge shifts east across the area, prior to backing to the south
and becoming strong and gusty Wednesday ahead of the next system
taking shape over the plains. The only concern tonight is the
possibility of LLWS at KUIN and KCOU as the low-level jet ramps up
during the late overnight and early morning. However, shear looks
marginal, thus have not mentioned in the TAF at this time.

Specifics for KSTL: Dry, VFR conditions expected to prevail
through the period. West-northwest winds will become light during
mid- to late afternoon as the ridge axis shifts across the area.
Overnight, the winds will begin to back to the south, increasing
in speed and becoming gusty Wednesday. Scattered diurnal cumulus
will clear tonight, with only high clouds expected on Wednesday.

JP

&&

.FIRE WEATHER:
Issued at 357 PM CDT Tue Apr 15 2014

Will be issuing a fire weather watch for Wednesday afternoon for a
small part of central and northeast Missouri. Model dewpoints are
too high based on recent trends and upstream dewpoints over the
central and southern Plains. Expected RH values tomorrow will be
in the lower 20s with southerly winds of 15 to 25 mph with higher
gusts.  These values along with 10 hour dry fuels falling below 9
percent warrant issuing a fire weather watch tomorrow.

Britt/JP

&&

.CLIMATE:

RECORD LOWS FOR 4/15:

STL - 27 IN 1928
COU - 25 IN 1928
UIN - 24 IN 1928
FAM - 24 IN 1928


&&

.LSX WATCHES/WARNINGS/ADVISORIES:
MO...FREEZE WARNING from 1 AM to 9 AM CDT Wednesday FOR Crawford MO-
     Iron MO-Jefferson MO-Madison MO-Reynolds MO-St. Francois MO-
     Ste. Genevieve MO-Washington MO.

     FIRE WEATHER WATCH from Wednesday morning through Wednesday
     evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Knox MO-
     Moniteau MO-Monroe MO-Shelby MO.

IL...FREEZE WARNING from 1 AM to 9 AM CDT Wednesday FOR Bond IL-
     Clinton IL-Fayette IL-Marion IL-Monroe IL-Montgomery IL-
     Randolph IL-St. Clair IL-Washington IL.

&&

$$

WFO LSX








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