000
FXUS63 KLSX 210443
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1143 PM CDT SUN MAY 20 2012

.UPDATE...
ISSUED AT 745 PM CDT SUN MAY 20 2012

TWO AREAS OF CONVECTION...ONE TO THE EAST...E OF A LINE FROM
LITCHFIELD IL TO CAPE GIRARDEAU MO AND THE OTHER TO THE W ROUGHLY
FROM SPRINGFIELD IL SWWD THRU VICHY MO. NEITHER ONE IS MOVING VERY
WELL...BUT THE WESTERN AREA HAS RECENTLY BEGUN TO SHOW INCREASED
SEWD MOVEMENT. CONVECTION SHOULD DISSIPATE FROM HERE ON OUT AS THE
ANNULAR ECLIPSED SUN SETS AND SFC-BASED INSTABILITY WANES.
LIKELIHOOD OF NEW CONVECTIVE NON-HYDROLOGIC WARNINGS IS SMALL WITH
MAIN THREAT FROM HERE BEING HEAVY RAINFALL IN SWRN IL.

SYNOPTIC CDFNT ITSELF IS ROUGHLY ALONG THE W AREA OF CONVECTION
WHICH IS FURTHER COMPLICATED OUT AHEAD OF IT WITH OUTFLOWS AND
COLD AIR POOLS FROM PRIOR CONVECTION IN SERN MO SO ITS IDENTITY
HAS ALSO WEAKENED FROM THIS.

MAY CONTINUE TO SEE SOME TSRA AFTER MIDNIGHT BUT IT SHOULD BE FEW
AND FAR BETWEEN AS ILL-DEFINED AND RE-ORGANIZING CDFNT WILL HAVE
PROCEEDED MOSTLY THRU THE FA BY THIS TIME.

TES

&&

.SHORT TERM...
ISSUED AT 239 PM CDT SUN MAY 20 2012
(TONIGHT AND MONDAY)

COLD FRONT EXTENDING FROM SFC LOW OVER NRN WI SW THROUGH CNTRL MO TO
NERN OK WILL CONTINUE MOVING SEWD TGT. SCATTERED SHOWERS AND STORMS
WILL CONTINUE THIS EVNG ALONG AND AHEAD OF THIS FRONT ACROSS SERN MO
AND SWRN IL...S AND E OF STL AND AHEAD OF A SHORTWAVE...VORT MAX NOW
OVER SWRN MO NWRN AR WHICH WILL MOVE NEWD THROUGH SERN MO AND SRN
IL.  THIS ACTIVITY SHOULD EVENTUALLY SHIFT SE OF OUR FORECAST AREA
LATE TGT AS COOLER AND DRIER AIR FILTERS INTO THE REGION AS A SFC
RIDGE BUILDS SEWD INTO MO BEHIND THE COLD FRONT.  COOLER
TEMPERATURES CAN BE EXPECTED TGT DUE TO CAA BEHIND THE COLD FRONT
WITH THE NAM MODEL DROPPING THE 8 DEGREE C 850 MB ISOTHERM SWD TO
STL BY 12Z MON.  COOLER CONDITIONS WILL CONTINUE ON MON WITH
TEMPERATURES AT OR SLIGHTLY BELOW NORMAL FOR LATE MAY.

GKS

&&

.LONG TERM...
ISSUED AT 239 PM CDT SUN MAY 20 2012
(MONDAY NIGHT TO NEXT SUNDAY)

DRY WEATHER IS STILL EXPECTED FROM MONDAY NIGHT THROUGH AT LEAST
MIDWEEK AS UPPER RIDGE BUILDS IN OVER MO/IL.  NEW RUNS OF THE GFS
AND CANADIAN GEM ARE NOW BRINGING A FRONT SOUTHWARD INTO THE AREA BY
FRIDAY THAT WILL LINGER OVER THE AREA INTO THE HOLIDAY WEEKEND.  GFS
HAS SOME QPF ALONG THE FRONT WHICH DEVIATES GOING FORECAST...BUT AM
NOT READY TO INTRODUCE RAIN NEXT WEEKEND AT THIS POINT. THESE
MODELS NOW LACK CONTINUITY AND THE FRONT WILL BE MOVING IN UNDER
THE UPPER RIDGE WHICH SHOULD ACT TO SUPPRESS THUNDERSTORM DEVELOPMENT.
THE GFS ENSEMBLE MEAN AND MORE CONSISTENT ECMWF DO NOT BRING THE
FRONT AS FAR SOUTH.

TEMPERATURES ON MONDAY AND TUESDAY NIGHT WILL BE RELATIVELY CHILLY
FOR LATE MAY AS SURFACE HIGH MOVES SLOWLY ACROSS MISSOURI AND
ILLINOIS.  GOOD RADIATIONAL COOLING AND THE 40`S DEWPOINTS SETTLING
IN FROM THE UPPER MIDWEST FAVOR TEMPERATURES FALLING BELOW NORMAL...
PARTICULARLY OVER THE EASTERN OZARKS.  BIG WARMUP IS STILL FAVORED
LATE WEEK INTO NEXT WEEKEND.  THINK 850MB TEMPERATURES WILL STILL BE
AROUND 20C LIKE THE ECMWF GIVEN THE EXPECTED DRY FORECAST. STILL
FAVOR SURFACE TEMPERATURES AT OR ABOUT 90F DURING THIS PERIOD.

BRITT

&&

.AVIATION...
ISSUED AT 1134 PM CDT SUN MAY 20 2012

CDFNT HAS MOVE E OF SUS/STL AND IS EXPECTED TO BE JUST E OF CPS AT
06Z. THEREFORE...VFR AND DRY CONDITIONS ARE EXPECTED THRU THE TAF
PERIOD. NWLY WINDS WILL BECOME NLY AND INCREASE TO AROUND 12KTS.
SOME HIGHER GUSTS TO AROUND 20 KTS WILL BE POSSIBLE DURING THE
AFTERNOON HRS...BUT WILL LET FUTURE UPDATES TAKE ANOTHER LOOK TO
SEE IF THIS NEEDS TO BE MENTIONED. WINDS WILL BECOME LIGHT AFTER
SUNSET MON EVE. AIRMASS WILL BE DRY ENUF THAT FG IS NOT
ANTICIPATED ATTM.

SPECIFICS FOR KSTL...VFR AND DRY THRU THE TAF PERIOD. NWLY WINDS
OVERNIGHT WILL BECOME NLY MON MORNING. FEW-SCT CU WILL DEVELOP
LATE MORNING AND DISSIPATE AFTER SUNSET.

TILLY

&&

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

$$

WFO LSX

000
FXUS63 KSGF 210430
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
1130 PM CDT SUN MAY 20 2012

...UPDATE TO AVIATION...

.DISCUSSION...

THE MAIN FORECAST CONCERN IN THE IMMEDIATE SHORT TERM WAS
DETERMINING WHEN CONVECTION WILL END ACROSS SOUTHERN MISSOURI.
TEMPERATURES THEN BECOME THE MAIN TOPIC AS A PATTERN CHANGE
COMMENCES LATER THIS WEEK.

CURRENTLY...UPPER LEVEL SHORT WAVE ENERGY IS TRACKING EAST ACROSS
THE WESTERN GREAT LAKES. A SURFACE LOW WAS LOCATED ACROSS NORTHERN
WISCONSIN...WITH A COLD FRONT TRAILING THE LOW ALL THE WAY INTO
THE SOUTHERN PLAINS. AS OF 3 PM...THE FRONT NEARLY BISECTED THE
MISSOURI OZARKS FROM NORTHEAST TO SOUTHWEST. SCATTERED SHOWERS AND
THUNDERSTORMS HAD DEVELOPED AHEAD OF THE FRONT JUST TO THE SOUTH
AND EAST OF THE INTERSTATE 44 CORRIDOR. WHILE THERE HAVE BEEN SOME
FAIRLY ROBUST UPDRAFTS...THEY HAVE BEEN SHORT LIVED DUE TO WEAK
LARGE SCALE SHEAR.

AS WE HEAD INTO TONIGHT...THAT FRONT WILL CONTINUE TO SLOWLY
PROGRESS SOUTHEAST. THE 850 MB FRONT WILL BE A BIT SLOWER TO
CLEAR...WHICH DOES OPEN A SMALL WINDOW FOR ADDITIONAL CONVECTION
ACROSS SOUTHERN MISSOURI INTO LATER TONIGHT. THUS...HELD ON TO
20-30 POPS OVERNIGHT. THERMODYNAMIC PROFILES MAY SUPPORT SMALL HAIL
AND BRIEF GUSTY WINDS WITH A FEW STORMS...BUT THE LACK OF SHEAR
WILL PRECLUDE A SEVERE THREAT.

VERY PLEASANT CONDITIONS ARE THEN EXPECTED TO START THE WORK WEEK
AS SURFACE HIGH PRESSURE BUILDS INTO THE OZARKS. FAIRLY CHILLY
TEMPERATURES ARE EXPECTED MONDAY NIGHT AS THAT HIGH SETTLES
OVERHEAD. MANY LOCATIONS ARE EXPECTED TO DIP INTO THE 40S BY EARLY
TUESDAY MORNING.

THE LARGE SCALE PATTERN WILL THEN BEGIN TO AMPLIFY DURING THE
LAST HALF OF THE WEEK. A LONG WAVE TROUGH WILL DEVELOP OVER THE
WESTERN UNITED STATES WITH STRONG POSITIVE HEIGHT ANOMALIES
DEVELOPING OFF THE SOUTHEASTERN UNITED STATES COAST. THIS REGIME
WILL SUPPORT A SYNOPTIC SCALE MID/UPPER LEVEL HIGH STRENGTHENING
OVER THE MID MISSISSIPPI VALLEY REGION. THE 12Z GFS SEEMS RATHER
BULLISH BRINGING A FRONTAL BOUNDARY INTO THE REGION FROM THURSDAY
INTO THE UPCOMING WEEKEND. THE 12Z ECMWF ON THE OTHER HAND KEEPS
THE FRONT WELL TO OUR NORTHWEST. AT THIS POINT...PREFER THE ECMWF
GIVEN THE POSITION OF THE LONG WAVE AND SYNOPTIC RIDGES. HAVE
THEREFORE KEPT THE FORECAST DRY THROUGH THE UPCOMING WEEKEND. THE
ECMWF CONTINUES TO ADVERTISE 850 MB TEMPERATURES EXCEEDING 20
DEGREES CELSIUS SPREADING IN FROM THE WEST STARTING ON THURSDAY.
THUS...HIGHS IN THE LOWER 90S SEEM LIKE A GOOD BET BY LATE THIS
WEEK.

SCHAUMANN


&&

.AVIATION...
/ISSUED 1120 PM CDT SUN MAY 20 2012/

FOR THE 20/0600Z KSGF/KJLN/KBBG TAFS...A WEAK COLD FRONT CONTINUES
TO MOVE SOUTH OF THE REGION. THE MAIN "PUSH" OF NORTH WINDS IS
STILL NORTH OF I-44. MAIN CONCERN WILL BE SOME SHALLOW FOG OVER
THE NEXT FEW HOURS AT KSGF WERE RAIN FROM TSTMS FELL EARLIER THIS
EVENING. FOR NOW...WILL BE CONSERVATIVE WITH HITTING LOWER FLIGHT
CATS WITH WEAK DRY ADVECTION OVERNIGHT...BUT TRENDS WILL NEED TO BE
MONITORED. OTHERWISE...SFC HIGH PRESSURE MOVING INTO THE REGION ON
MONDAY WILL LEAD TO VFR CONDITIONS.

DSA

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 210045
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
745 PM CDT SUN MAY 20 2012

.UPDATE...
ISSUED AT 745 PM CDT SUN MAY 20 2012

TWO AREAS OF CONVECTION...ONE TO THE EAST...E OF A LINE FROM
LITCHFIELD IL TO CAPE GIRARDEAU MO AND THE OTHER TO THE W ROUGHLY
FROM SPRINGFIELD IL SWWD THRU VICHY MO. NEITHER ONE IS MOVING VERY
WELL...BUT THE WESTERN AREA HAS RECENTLY BEGUN TO SHOW INCREASED
SEWD MOVEMENT. CONVECTION SHOULD DISSIPATE FROM HERE ON OUT AS THE
ANNULAR ECLIPSED SUN SETS AND SFC-BASED INSTABILITY WANES.
LIKELIHOOD OF NEW CONVECTIVE NON-HYDROLOGIC WARNINGS IS SMALL WITH
MAIN THREAT FROM HERE BEING HEAVY RAINFALL IN SWRN IL.

SYNOPTIC CDFNT ITSELF IS ROUGHLY ALONG THE W AREA OF CONVECTION
WHICH IS FURTHER COMPLICATED OUT AHEAD OF IT WITH OUTFLOWS AND
COLD AIR POOLS FROM PRIOR CONVECTION IN SERN MO SO ITS IDENTITY
HAS ALSO WEAKENED FROM THIS.

MAY CONTINUE TO SEE SOME TSRA AFTER MIDNIGHT BUT IT SHOULD BE FEW
AND FAR BETWEEN AS ILL-DEFINED AND RE-ORGANIZING CDFNT WILL HAVE
PROCEEDED MOSTLY THRU THE FA BY THIS TIME.

TES

&&

.SHORT TERM...
ISSUED AT 239 PM CDT SUN MAY 20 2012
(TONIGHT AND MONDAY)

COLD FRONT EXTENDING FROM SFC LOW OVER NRN WI SW THROUGH CNTRL MO TO
NERN OK WILL CONTINUE MOVING SEWD TGT. SCATTERED SHOWERS AND STORMS
WILL CONTINUE THIS EVNG ALONG AND AHEAD OF THIS FRONT ACROSS SERN MO
AND SWRN IL...S AND E OF STL AND AHEAD OF A SHORTWAVE...VORT MAX NOW
OVER SWRN MO NWRN AR WHICH WILL MOVE NEWD THROUGH SERN MO AND SRN
IL.  THIS ACTIVITY SHOULD EVENTUALLY SHIFT SE OF OUR FORECAST AREA
LATE TGT AS COOLER AND DRIER AIR FILTERS INTO THE REGION AS A SFC
RIDGE BUILDS SEWD INTO MO BEHIND THE COLD FRONT.  COOLER
TEMPERATURES CAN BE EXPECTED TGT DUE TO CAA BEHIND THE COLD FRONT
WITH THE NAM MODEL DROPPING THE 8 DEGREE C 850 MB ISOTHERM SWD TO
STL BY 12Z MON.  COOLER CONDITIONS WILL CONTINUE ON MON WITH
TEMPERATURES AT OR SLIGHTLY BELOW NORMAL FOR LATE MAY.

GKS

&&

.LONG TERM...
ISSUED AT 239 PM CDT SUN MAY 20 2012
(MONDAY NIGHT TO NEXT SUNDAY)

DRY WEATHER IS STILL EXPECTED FROM MONDAY NIGHT THROUGH AT LEAST
MIDWEEK AS UPPER RIDGE BUILDS IN OVER MO/IL.  NEW RUNS OF THE GFS
AND CANADIAN GEM ARE NOW BRINGING A FRONT SOUTHWARD INTO THE AREA BY
FRIDAY THAT WILL LINGER OVER THE AREA INTO THE HOLIDAY WEEKEND.  GFS
HAS SOME QPF ALONG THE FRONT WHICH DEVIATES GOING FORECAST...BUT AM
NOT READY TO INTRODUCE RAIN NEXT WEEKEND AT THIS POINT. THESE
MODELS NOW LACK CONTINUITY AND THE FRONT WILL BE MOVING IN UNDER
THE UPPER RIDGE WHICH SHOULD ACT TO SUPPRESS THUNDERSTORM DEVELOPMENT.
THE GFS ENSEMBLE MEAN AND MORE CONSISTENT ECMWF DO NOT BRING THE
FRONT AS FAR SOUTH.

TEMPERATURES ON MONDAY AND TUESDAY NIGHT WILL BE RELATIVELY CHILLY
FOR LATE MAY AS SURFACE HIGH MOVES SLOWLY ACROSS MISSOURI AND
ILLINOIS.  GOOD RADIATIONAL COOLING AND THE 40`S DEWPOINTS SETTLING
IN FROM THE UPPER MIDWEST FAVOR TEMPERATURES FALLING BELOW NORMAL...
PARTICULARLY OVER THE EASTERN OZARKS.  BIG WARMUP IS STILL FAVORED
LATE WEEK INTO NEXT WEEKEND.  THINK 850MB TEMPERATURES WILL STILL BE
AROUND 20C LIKE THE ECMWF GIVEN THE EXPECTED DRY FORECAST. STILL
FAVOR SURFACE TEMPERATURES AT OR ABOUT 90F DURING THIS PERIOD.

BRITT

&&

.AVIATION...
ISSUED AT 551 PM CDT SUN MAY 20 2012

CDFNT CURRENTLY STRETCHES FROM NEAR KPQQ SWWD TO JUST E OF KJEF.
THIS FNT WILL CONTINUE TO SLOWLY MOVE EWD THIS EVENING WITH FROPA
AT SUS AND CPS AROUND 03Z. WITH TSRA JUST AHEAD OF THE FNT...THESE
TSRA MAY IMPACT SUS/CPS BRIEFLY EARLY THIS EVE. BELIEVE THESE TSRA
WILL DISSIPATE BEFORE REACHING THE TERMINALS...BUT MAY HAVE BRIEF
MENTION OF TSRA. WITH DRIER AIR MOVING IN BEHIND THE FNT...DO NOT
ANTICIPATE FG TONIGHT. WINDS WILL BECOME NWLY MON INCREASING TO
AROUND 12KTS. FEW-SCT CU WITH BASES AROUND 4 TO 5 KFT
EXPECTED...OTHERWISE SKC.

SPECIFICS FOR KSTL...MAY NEED BRIEF MENTION OF TSRA EARLY THIS EVE
BEFORE FROPA. BEHIND THE FNT...WINDS WILL BECOME NWLY OVERNIGHT
THEN NLY ON MON. WINDS WILL INCREASE TO AROUND 12KTS ON MON WITH
FEW-SCT CU DURING THE DAY.

TILLY

&&

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

$$

WFO LSX

000
FXUS63 KEAX 202323
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
623 PM CDT Sun May 20 2012


...UPDATED AVIATION DISCUSSION...


.DISCUSSION...

Short Range (Today through Tuesday)...

While beauty is often found in the eye of the beholder, thoughts are
that everyone will likely agree that the next couple of days will
be...beautiful! Shortwave that brought last nights frontal passage
continues to shift east, limiting the focus for any storms this
afternoon to areas south and east of our region. The cool surface
high sliding across the Lower Missouri River Valley behind the front
will keep temperatures below normal through Monday. However, as the
high slides to our east Monday winds will come around to the south,
beginning a warming trend that will persist through most of the
coming work week. As a result, temperatures by Tuesday should be
ranging from around, to a category or two above, normal with breezy
southwest winds.

Cutter

Medium Range (Wednesday through Sunday)...

The position of the quasi-stationary front will make or break the
extended forecast. Upper ridge builds over the eastern half of the
US during the extended period, bringing much above normal to around
record temps to the CWA, assuming the ECMWF and GEM are correct.
They keep the front mostly north of the CWA through the period,
which given the strength of the ridge, dry ground and modest
atmospheric moisture should allow temps to climb at least into the
low 90s. This scenario seems likely given the forecast strength and
position of the ridge. Contrast that with the GFS which continues to
forecast the front pushing against the upper flow into the ridge, a
scenario which doesn`t make much sense. Anyway, kept things close to
the previous forecast which is several degrees above first guess
inits. Have removed precip mention from these inits as well since
the moisture will be lacking and atmosphere capped in the warm
sector.

AB

&&

.AVIATION...

For the 00Z TAFs...high pressure will build in from the west through
the period, becoming centered over western MO by 00Z Tues. This will
cause any lingering cumulus to clear out through the evening hours
while winds become light and northeasterly through the period.

Hawblitzel

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KSGF 202317
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
617 PM CDT SUN MAY 20 2012

...UPDATE TO AVIATION...

.DISCUSSION...

THE MAIN FORECAST CONCERN IN THE IMMEDIATE SHORT TERM WAS
DETERMINING WHEN CONVECTION WILL END ACROSS SOUTHERN MISSOURI.
TEMPERATURES THEN BECOME THE MAIN TOPIC AS A PATTERN CHANGE
COMMENCES LATER THIS WEEK.

CURRENTLY...UPPER LEVEL SHORT WAVE ENERGY IS TRACKING EAST ACROSS
THE WESTERN GREAT LAKES. A SURFACE LOW WAS LOCATED ACROSS NORTHERN
WISCONSIN...WITH A COLD FRONT TRAILING THE LOW ALL THE WAY INTO
THE SOUTHERN PLAINS. AS OF 3 PM...THE FRONT NEARLY BISECTED THE
MISSOURI OZARKS FROM NORTHEAST TO SOUTHWEST. SCATTERED SHOWERS AND
THUNDERSTORMS HAD DEVELOPED AHEAD OF THE FRONT JUST TO THE SOUTH
AND EAST OF THE INTERSTATE 44 CORRIDOR. WHILE THERE HAVE BEEN SOME
FAIRLY ROBUST UPDRAFTS...THEY HAVE BEEN SHORT LIVED DUE TO WEAK
LARGE SCALE SHEAR.

AS WE HEAD INTO TONIGHT...THAT FRONT WILL CONTINUE TO SLOWLY
PROGRESS SOUTHEAST. THE 850 MB FRONT WILL BE A BIT SLOWER TO
CLEAR...WHICH DOES OPEN A SMALL WINDOW FOR ADDITIONAL CONVECTION
ACROSS SOUTHERN MISSOURI INTO LATER TONIGHT. THUS...HELD ON TO
20-30 POPS OVERNIGHT. THERMODYNAMIC PROFILES MAY SUPPORT SMALL HAIL
AND BRIEF GUSTY WINDS WITH A FEW STORMS...BUT THE LACK OF SHEAR
WILL PRECLUDE A SEVERE THREAT.

VERY PLEASANT CONDITIONS ARE THEN EXPECTED TO START THE WORK WEEK
AS SURFACE HIGH PRESSURE BUILDS INTO THE OZARKS. FAIRLY CHILLY
TEMPERATURES ARE EXPECTED MONDAY NIGHT AS THAT HIGH SETTLES
OVERHEAD. MANY LOCATIONS ARE EXPECTED TO DIP INTO THE 40S BY EARLY
TUESDAY MORNING.

THE LARGE SCALE PATTERN WILL THEN BEGIN TO AMPLIFY DURING THE
LAST HALF OF THE WEEK. A LONG WAVE TROUGH WILL DEVELOP OVER THE
WESTERN UNITED STATES WITH STRONG POSITIVE HEIGHT ANOMALIES
DEVELOPING OFF THE SOUTHEASTERN UNITED STATES COAST. THIS REGIME
WILL SUPPORT A SYNOPTIC SCALE MID/UPPER LEVEL HIGH STRENGTHENING
OVER THE MID MISSISSIPPI VALLEY REGION. THE 12Z GFS SEEMS RATHER
BULLISH BRINGING A FRONTAL BOUNDARY INTO THE REGION FROM THURSDAY
INTO THE UPCOMING WEEKEND. THE 12Z ECMWF ON THE OTHER HAND KEEPS
THE FRONT WELL TO OUR NORTHWEST. AT THIS POINT...PREFER THE ECMWF
GIVEN THE POSITION OF THE LONG WAVE AND SYNOPTIC RIDGES. HAVE
THEREFORE KEPT THE FORECAST DRY THROUGH THE UPCOMING WEEKEND. THE
ECMWF CONTINUES TO ADVERTISE 850 MB TEMPERATURES EXCEEDING 20
DEGREES CELSIUS SPREADING IN FROM THE WEST STARTING ON THURSDAY.
THUS...HIGHS IN THE LOWER 90S SEEM LIKE A GOOD BET BY LATE THIS
WEEK.

SCHAUMANN


&&

.AVIATION...

FOR THE 00Z TAFS...VFR WILL PREVAIL THROUGH TOMORROW EVENING. HAVE
INCLUDED SOME EARLY VCTS AND CB FOR SGF AND BBG THROUGH 01Z THIS
EVENING BUT ALL ACTIVITY WILL DISSIPATE NEAR SUNSET. LOOK FOR HIGH
PRESSURE BUILDING IN WITH LIGHT NORTHERLY WINDS AND MOSTLY CLEAR SKIES.

GRIFFIN

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 202303
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
603 PM CDT SUN MAY 20 2012

.SHORT TERM...
ISSUED AT 239 PM CDT SUN MAY 20 2012
(TONIGHT AND MONDAY)

COLD FRONT EXTENDING FROM SFC LOW OVER NRN WI SW THROUGH CNTRL MO TO
NERN OK WILL CONTINUE MOVING SEWD TGT. SCATTERED SHOWERS AND STORMS
WILL CONTINUE THIS EVNG ALONG AND AHEAD OF THIS FRONT ACROSS SERN MO
AND SWRN IL...S AND E OF STL AND AHEAD OF A SHORTWAVE...VORT MAX NOW
OVER SWRN MO NWRN AR WHICH WILL MOVE NEWD THROUGH SERN MO AND SRN
IL.  THIS ACTIVITY SHOULD EVENTUALLY SHIFT SE OF OUR FORECAST AREA
LATE TGT AS COOLER AND DRIER AIR FILTERS INTO THE REGION AS A SFC
RIDGE BUILDS SEWD INTO MO BEHIND THE COLD FRONT.  COOLER
TEMPERATURES CAN BE EXPECTED TGT DUE TO CAA BEHIND THE COLD FRONT
WITH THE NAM MODEL DROPPING THE 8 DEGREE C 850 MB ISOTHERM SWD TO
STL BY 12Z MON.  COOLER CONDITIONS WILL CONTINUE ON MON WITH
TEMPERATURES AT OR SLIGHTLY BELOW NORMAL FOR LATE MAY.

GKS

&&

.LONG TERM...
ISSUED AT 239 PM CDT SUN MAY 20 2012
(MONDAY NIGHT TO NEXT SUNDAY)

DRY WEATHER IS STILL EXPECTED FROM MONDAY NIGHT THROUGH AT LEAST
MIDWEEK AS UPPER RIDGE BUILDS IN OVER MO/IL.  NEW RUNS OF THE GFS
AND CANADIAN GEM ARE NOW BRINGING A FRONT SOUTHWARD INTO THE AREA BY
FRIDAY THAT WILL LINGER OVER THE AREA INTO THE HOLIDAY WEEKEND.  GFS
HAS SOME QPF ALONG THE FRONT WHICH DEVIATES GOING FORECAST...BUT AM
NOT READY TO INTRODUCE RAIN NEXT WEEKEND AT THIS POINT. THESE
MODELS NOW LACK CONTINUITY AND THE FRONT WILL BE MOVING IN UNDER
THE UPPER RIDGE WHICH SHOULD ACT TO SUPPRESS THUNDERSTORM DEVELOPMENT.
THE GFS ENSEMBLE MEAN AND MORE CONSISTENT ECMWF DO NOT BRING THE
FRONT AS FAR SOUTH.

TEMPERATURES ON MONDAY AND TUESDAY NIGHT WILL BE RELATIVELY CHILLY
FOR LATE MAY AS SURFACE HIGH MOVES SLOWLY ACROSS MISSOURI AND
ILLINOIS.  GOOD RADIATIONAL COOLING AND THE 40`S DEWPOINTS SETTLING
IN FROM THE UPPER MIDWEST FAVOR TEMPERATURES FALLING BELOW NORMAL...
PARTICULARLY OVER THE EASTERN OZARKS.  BIG WARMUP IS STILL FAVORED
LATE WEEK INTO NEXT WEEKEND.  THINK 850MB TEMPERATURES WILL STILL BE
AROUND 20C LIKE THE ECMWF GIVEN THE EXPECTED DRY FORECAST. STILL
FAVOR SURFACE TEMPERATURES AT OR ABOUT 90F DURING THIS PERIOD.

BRITT

&&

.AVIATION...
ISSUED AT 551 PM CDT SUN MAY 20 2012

CDFNT CURRENTLY STRETCHES FROM NEAR KPQQ SWWD TO JUST E OF KJEF.
THIS FNT WILL CONTINUE TO SLOWLY MOVE EWD THIS EVENING WITH FROPA
AT SUS AND CPS AROUND 03Z. WITH TSRA JUST AHEAD OF THE FNT...THESE
TSRA MAY IMPACT SUS/CPS BRIEFLY EARLY THIS EVE. BELIEVE THESE TSRA
WILL DISSIPATE BEFORE REACHING THE TERMINALS...BUT MAY HAVE BRIEF
MENTION OF TSRA. WITH DRIER AIR MOVING IN BEHIND THE FNT...DO NOT
ANTICIPATE FG TONIGHT. WINDS WILL BECOME NWLY MON INCREASING TO
AROUND 12KTS. FEW-SCT CU WITH BASES AROUND 4 TO 5 KFT
EXPECTED...OTHERWISE SKC.

SPECIFICS FOR KSTL...MAY NEED BRIEF MENTION OF TSRA EARLY THIS EVE
BEFORE FROPA. BEHIND THE FNT...WINDS WILL BECOME NWLY OVERNIGHT
THEN NLY ON MON. WINDS WILL INCREASE TO AROUND 12KTS ON MON WITH
FEW-SCT CU DURING THE DAY.

TILLY

&&

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

$$

WFO LSX

000
FXUS63 KSGF 202023
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
323 PM CDT SUN MAY 20 2012

.DISCUSSION...

THE MAIN FORECAST CONCERN IN THE IMMEDIATE SHORT TERM WAS
DETERMINING WHEN CONVECTION WILL END ACROSS SOUTHERN MISSOURI.
TEMPERATURES THEN BECOME THE MAIN TOPIC AS A PATTERN CHANGE
COMMENCES LATER THIS WEEK.

CURRENTLY...UPPER LEVEL SHORT WAVE ENERGY IS TRACKING EAST ACROSS
THE WESTERN GREAT LAKES. A SURFACE LOW WAS LOCATED ACROSS NORTHERN
WISCONSIN...WITH A COLD FRONT TRAILING THE LOW ALL THE WAY INTO
THE SOUTHERN PLAINS. AS OF 3 PM...THE FRONT NEARLY BISECTED THE
MISSOURI OZARKS FROM NORTHEAST TO SOUTHWEST. SCATTERED SHOWERS AND
THUNDERSTORMS HAD DEVELOPED AHEAD OF THE FRONT JUST TO THE SOUTH
AND EAST OF THE INTERSTATE 44 CORRIDOR. WHILE THERE HAVE BEEN SOME
FAIRLY ROBUST UPDRAFTS...THEY HAVE BEEN SHORT LIVED DUE TO WEAK
LARGE SCALE SHEAR.

AS WE HEAD INTO TONIGHT...THAT FRONT WILL CONTINUE TO SLOWLY
PROGRESS SOUTHEAST. THE 850 MB FRONT WILL BE A BIT SLOWER TO
CLEAR...WHICH DOES OPEN A SMALL WINDOW FOR ADDITIONAL CONVECTION
ACROSS SOUTHERN MISSOURI INTO LATER TONIGHT. THUS...HELD ON TO
20-30 POPS OVERNIGHT. THERMODYNAMIC PROFILES MAY SUPPORT SMALL HAIL
AND BRIEF GUSTY WINDS WITH A FEW STORMS...BUT THE LACK OF SHEAR
WILL PRECLUDE A SEVERE THREAT.

VERY PLEASANT CONDITIONS ARE THEN EXPECTED TO START THE WORK WEEK
AS SURFACE HIGH PRESSURE BUILDS INTO THE OZARKS. FAIRLY CHILLY
TEMPERATURES ARE EXPECTED MONDAY NIGHT AS THAT HIGH SETTLES
OVERHEAD. MANY LOCATIONS ARE EXPECTED TO DIP INTO THE 40S BY EARLY
TUESDAY MORNING.

THE LARGE SCALE PATTERN WILL THEN BEGIN TO AMPLIFY DURING THE
LAST HALF OF THE WEEK. A LONG WAVE TROUGH WILL DEVELOP OVER THE
WESTERN UNITED STATES WITH STRONG POSITIVE HEIGHT ANOMALIES
DEVELOPING OFF THE SOUTHEASTERN UNITED STATES COAST. THIS REGIME
WILL SUPPORT A SYNOPTIC SCALE MID/UPPER LEVEL HIGH STRENGTHENING
OVER THE MID MISSISSIPPI VALLEY REGION. THE 12Z GFS SEEMS RATHER
BULLISH BRINGING A FRONTAL BOUNDARY INTO THE REGION FROM THURSDAY
INTO THE UPCOMING WEEKEND. THE 12Z ECMWF ON THE OTHER HAND KEEPS
THE FRONT WELL TO OUR NORTHWEST. AT THIS POINT...PREFER THE ECMWF
GIVEN THE POSITION OF THE LONG WAVE AND SYNOPTIC RIDGES. HAVE
THEREFORE KEPT THE FORECAST DRY THROUGH THE UPCOMING WEEKEND. THE
ECMWF CONTINUES TO ADVERTISE 850 MB TEMPERATURES EXCEEDING 20
DEGREES CELSIUS SPREADING IN FROM THE WEST STARTING ON THURSDAY.
THUS...HIGHS IN THE LOWER 90S SEEM LIKE A GOOD BET BY LATE THIS
WEEK.

SCHAUMANN

&&

.AVIATION...

FOR THE 18Z TAFS...

RATHER COMPLEX FORECAST FOR THE TERMINALS THROUGH THE REMAINDER OF
THE DAY TODAY. A SLOW MOVING COLD FRONT WILL SERVE AS THE FOCUS
FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON. THIS FRONT HAS JUST
PASSED JLN...AND THUS HAVE REMOVED TSRA MENTION FROM THAT TAF. FOR
SGF AND BBG...MAINTAINED TEMPO MENTION THROUGH THE AFTERNOON
HOURS. THE FRONT SHOULD CLEAR THE TERMINALS BY EVENING...ENDING
THE THREAT FOR TSRA...AND TURNING WINDS TO THE NORTH.

BOXELL

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KEAX 202013
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
313 PM CDT Sun May 20 2012

.DISCUSSION...

Short Range (Today through Tuesday)...

While beauty is often found in the eye of the beholder, thoughts are
that everyone will likely agree that the next couple of days will
be...beautiful! Shortwave that brought last nights frontal passage
continues to shift east, limiting the focus for any storms this
afternoon to areas south and east of our region. The cool surface
high sliding across the Lower Missouri River Valley behind the front
will keep temperatures below normal through Monday. However, as the
high slides to our east Monday winds will come around to the south,
beginning a warming trend that will persist through most of the
coming work week. As a result, temperatures by Tuesday should be
ranging from around, to a category or two above, normal with breezy
southwest winds.

Cutter

Medium Range (Wednesday through Sunday)...

The position of the quasi-stationary front will make or break the
extended forecast. Upper ridge builds over the eastern half of the
US during the extended period, bringing much above normal to around
record temps to the CWA, assuming the ECMWF and GEM are correct.
They keep the front mostly north of the CWA through the period,
which given the strength of the ridge, dry ground and modest
atmospheric moisture should allow temps to climb at least into the
low 90s. This scenario seems likely given the forecast strength and
position of the ridge. Contrast that with the GFS which continues to
forecast the front pushing against the upper flow into the ridge, a
scenario which doesn`t make much sense. Anyway, kept things close to
the previous forecast which is several degrees above first guess
inits. Have removed precip mention from these inits as well since
the moisture will be lacking and atmosphere capped in the warm
sector.

AB

&&

.AVIATION...

For the 18Z TAFs...Late this morning a low cloud deck moved into the
terminals with ceilings floating just around the upper the upper end
of MVFR criteria, though as the afternoon grows old expectation are
that the clouds will scatter back out leaving VFR conditions to
prevail over the next 24 hours. Otherwise, look for our breezy north
wind to slowly veer around to the northeast by Monday morning as the
surface high shifts east across the Plains States.

Cutter

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KLSX 201946
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
246 PM CDT SUN MAY 20 2012

.SHORT TERM...
ISSUED AT 239 PM CDT SUN MAY 20 2012
(TONIGHT AND MONDAY)

COLD FRONT EXTENDING FROM SFC LOW OVER NRN WI SW THROUGH CNTRL MO TO
NERN OK WILL CONTINUE MOVING SEWD TGT. SCATTERED SHOWERS AND STORMS
WILL CONTINUE THIS EVNG ALONG AND AHEAD OF THIS FRONT ACROSS SERN MO
AND SWRN IL...S AND E OF STL AND AHEAD OF A SHORTWAVE...VORT MAX NOW
OVER SWRN MO NWRN AR WHICH WILL MOVE NEWD THROUGH SERN MO AND SRN
IL.  THIS ACTIVITY SHOULD EVENTUALLY SHIFT SE OF OUR FORECAST AREA
LATE TGT AS COOLER AND DRIER AIR FILTERS INTO THE REGION AS A SFC
RIDGE BUILDS SEWD INTO MO BEHIND THE COLD FRONT.  COOLER
TEMPERATURES CAN BE EXPECTED TGT DUE TO CAA BEHIND THE COLD FRONT
WITH THE NAM MODEL DROPPING THE 8 DEGREE C 850 MB ISOTHERM SWD TO
STL BY 12Z MON.  COOLER CONDITIONS WILL CONTINUE ON MON WITH
TEMPERATURES AT OR SLIGHTLY BELOW NORMAL FOR LATE MAY.

GKS

&&

.LONG TERM...
ISSUED AT 239 PM CDT SUN MAY 20 2012
(MONDAY NIGHT TO NEXT SUNDAY)

DRY WEATHER IS STILL EXPECTED FROM MONDAY NIGHT THROUGH AT LEAST
MIDWEEK AS UPPER RIDGE BUILDS IN OVER MO/IL.  NEW RUNS OF THE GFS
AND CANADIAN GEM ARE NOW BRINGING A FRONT SOUTHWARD INTO THE AREA BY
FRIDAY THAT WILL LINGER OVER THE AREA INTO THE HOLIDAY WEEKEND.  GFS
HAS SOME QPF ALONG THE FRONT WHICH DEVIATES GOING FORECAST...BUT AM
NOT READY TO INTRODUCE RAIN NEXT WEEKEND AT THIS POINT. THESE
MODELS NOW LACK CONTINUITY AND THE FRONT WILL BE MOVING IN UNDER
THE UPPER RIDGE WHICH SHOULD ACT TO SUPPRESS THUNDERSTORM DEVELOPMENT.
THE GFS ENSEMBLE MEAN AND MORE CONSISTENT ECMWF DO NOT BRING THE
FRONT AS FAR SOUTH.

TEMPERATURES ON MONDAY AND TUESDAY NIGHT WILL BE RELATIVELY CHILLY
FOR LATE MAY AS SURFACE HIGH MOVES SLOWLY ACROSS MISSOURI AND
ILLINOIS.  GOOD RADIATIONAL COOLING AND THE 40`S DEWPOINTS SETTLING
IN FROM THE UPPER MIDWEST FAVOR TEMPERATURES FALLING BELOW NORMAL...
PARTICULARLY OVER THE EASTERN OZARKS.  BIG WARMUP IS STILL FAVORED
LATE WEEK INTO NEXT WEEKEND.  THINK 850MB TEMPERATURES WILL STILL BE
AROUND 20C LIKE THE ECMWF GIVEN THE EXPECTED DRY FORECAST. STILL
FAVOR SURFACE TEMPERATURES AT OR ABOUT 90F DURING THIS PERIOD.

BRITT

&&

.AVIATION...
ISSUED AT 1147 AM CDT SUN MAY 20 2012

COLD FRONT EXTENDING FROM SFC LOW OVER NWRN WI SW TO JUST W OF
UIN AND COU WILL MOVE SEWD THROUGH THE TAF SITES THIS AFTN INTO
THE EARLY EVNG. THIS FRONT SHOULD MOVE THROUGH UIN AND COU AROUND
18-19Z SUN AND THROUGH THE STL METRO AREA TAF SITES LATE THIS AFTN.
ALTHOUGH THERE WAS CURRENTLY LITTLE PRECIPITATION ALONG THIS FRONT
WIDELY SCATTERED TO SCATTERED SHOWERS AND STORMS SHOULD DEVELOP
THIS AFTN WITH PLENTY OF INSTABILITY ALONG AND AHEAD OF THE FRONT.
A SHORTWAVE OVER SWRN MO WILL ALSO BE MOVING NEWD THROUGH THE AREA
HELPING TO INITIATE CONVECTION ALONG THE FRONT DESPITE ONLY WEAK
SFC CONVERGENCE. WITH LIMITED COVERAGE OF SHOWERS/STORMS WILL
CONTINUE WITH JUST VCTS IN THE TAFS THIS AFTN. WILL PUT VCTS IN
THE UIN AND COU TAFS EARLY THIS AFTN AND IN THE STL METRO AREA
TAFS LATE THIS AFTN. WITH DIURNAL HEATING CUMULUS CLOUDS SHOULD
CONTINUE TO DEVELOP BECOMING BKN BRIEFLY. SOME POST FRONTAL
CUMULUS OR STRATOCUMULUS CLOUDS OVER NWRN MO MAY ALSO ADVECT SEWD
INTO THE TAF SITES LATE THIS AFTN AND THIS EVNG. MOST OF THIS
SHOULD BE VFR. SWLY SFC WIND WILL VEER AROUND TO A NWLY DIRECTION
AFTER FROPA THIS AFTN AND EARLY THIS EVNG. MODELS DEPICT MOISTURE
AROUND 850 MB AT 06Z MON SO SCT CUMULUS OR STRATOCUMULUS CLOUDS
MAY CONTINUE LATE TGT.

SPECIFICS FOR KSTL...VFR CUMULUS CLOUDS SHOULD CONTINUE TO DEVELOP
THIS AFTN GOING BKN AT TIMES. WILL INCLUDE VCTS IN THE STL TAF
FOR LATE THIS AFTN WITH AT LEAST WIDELY SCATTERED SHRA/TSRA
EXPECTED. W-SWLY SFC WIND WILL VEER AROUND TO A NWLY DIRECTION
LATE THIS AFTN AND EARLY THIS EVNG AFTER FROPA. SCATTERED CUMULUS
OR STRATOCUMULUS CLOUDS WILL CONTINUE TGT WITH POST FRONTAL LOW
LEVEL MOISTURE MOVING THROUGH THE AREA. FEW-SCT DIURNAL CUMULUS
CLOUDS MAY ALSO DEVELOP ON MON WITH N-NWLY SFC WINDS AS A SFC
RIDGE BUILDS SEWD INTO MO BEHIND THE COLD FRONT.

GKS

&&

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

$$

WFO LSX

000
FXUS63 KLSX 201754
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1254 PM CDT SUN MAY 20 2012

.SYNOPSIS...
ISSUED AT 243 AM CDT SUN MAY 20 2012

A SHORTWAVE TROF IS LOCATED ACROSS THE CENTRAL PLAINS...WITH A
STUBBORN UPPER LEVEL RIDGE PARKED ACROSS THE LOWER OHIO RIVER
VALLEY. AT THE SURFACE...A COLD FRONT EXTENDS FROM WEAK LOW PRESSURE
ACROSS NORTHWEST WISCONSIN...THROUGH SOUTHEAST MINNESOATA...CENTRAL
IOWA AND INTO EASTERN KANSAS/CENTRAL OKLAHOMA.

REGIONAL RADAR SHOWS A SPLATTERING OF REMNANT SHOWERS AND
THUNDERSTORMS FROM DIURNAL CONVECTION ACROSS SOUTHEAST KANSAS AND
OKLAHOMA. OTHERWISE...UPPER LEVEL RIDGE CONTINUES TO BLOCK EASTERN
PROGRESS OF CIRRUS SHIELD TO THE EAST OF THE MISSISSIPPI RIVER
VALLEY.

CVKING

&&

.SHORT TERM...
ISSUED AT 243 AM CDT SUN MAY 20 2012
(TODAY AND TONIGHT)

TEMPERATURE FORECAST A BIT TRICKY TODAY AS LOCATIONS ALONG AND
EAST OF THE MISSISSIPPI RIVER HAVE THE POTENTIAL TO WARM BACK INTO
THE UPPER 80S AND PERHAPS LOWER 90S GIVEN UNSEASONABLY WARM START
AND SUNSHINE THIS MORNING. FURTHER WEST...CLOUD COVER WILL ACT TO
LIMIT DIURNAL TEMPERATURE RISE. THIS SHOULD RESULT IN QUITE A
TEMPERATURE CONTRAST FROM WEST TO EAST.

THE SHORTWAVE TROF SPINNING NORTHEAST INTO THE UPPER MIDWEST WILL
SEND A COLD FRONT SOUTH THROUGH THE CWA THIS AFTERNOON AND EVENING.
SCATTERED CONVECTION IS EXPECTED ALONG AND AHEAD OF THE
FRONT...LARGELY TIED TO DIURNAL INSTABILITY. DEEP LAYER SHEAR
REMAINS WEAK WHICH SHOULD KEEP ANY SEVERE WEATHER REPORTS MARGINAL
AND ISOLATED TO THE STRONGEST STORMS.

UPSTREAM POST FRONTAL OBSERVATIONS ACROSS THE DAKOTAS AND NEBRASKA
INDICATE TEMPERATURES WILL DROP SIGNIFICANTLY TONIGHT AND HAVE
LOWERED THEM ACCORDINGLY.

CVKING

&&

.LONG TERM...
ISSUED AT 243 AM CDT SUN MAY 20 2012
(MONDAY THROUGH HOLIDAY WEEKEND)

HIGH PRESSURE QUICKLY BUILDS INTO THE MIDWEST ON MONDAY WITH MUCH
COOLER TEMPERATURES EXPECTED MONDAY AND MONDAY NIGHT. BUT...AS THE
SURFACE HIGH MOVES EAST OF THE AREA AND UPPER LEVEL RIDGE BEGINS TO
TAKE HOLD OF THE CENTER OF THE CONUS A WARMING TREND WILL COMMENCE
BY MIDWEEK. HAVE INCREASED TEMPERATURES ABOVE GUIDANCE FRIDAY AND
SATURDAY AS THEY ARE BEING SKEWED TOWARD COOLER CLIMO NUMBERS. THE
ECWMF MODEL HAS BEEN CONSISTENT IN FORECASTING 2 METER
TEMPERATURES IN THE MIDDLE TO UPPER 90S FOR THE HOLIDAY WEEKEND AS
A 595 DM UPPER LEVEL HIGH BUILDS ACROSS THE LOWER OHIO RIVER
VALLEY. EXPECT DEWPOINTS WILL MIX OUT EACH AFTERNOON GIVEN HOW DRY
WE HAVE BEEN LATELY AND A FAVORABLE SOUTHWEST FLOW AT THE SURFACE.
SO DON`T EXPECT WE WILL MEET OFFICIAL HEAT INDEX CRITERIA...BUT
IT WILL BE HOT FOR THE UNOFFICIAL START OF SUMMER.

CVKING

&&

.AVIATION...
ISSUED AT 1147 AM CDT SUN MAY 20 2012

COLD FRONT EXTENDING FROM SFC LOW OVER NWRN WI SW TO JUST W OF
UIN AND COU WILL MOVE SEWD THROUGH THE TAF SITES THIS AFTN INTO
THE EARLY EVNG. THIS FRONT SHOULD MOVE THROUGH UIN AND COU AROUND
18-19Z SUN AND THROUGH THE STL METRO AREA TAF SITES LATE THIS AFTN.
ALTHOUGH THERE WAS CURRENTLY LITTLE PRECIPITATION ALONG THIS FRONT
WIDELY SCATTERED TO SCATTERED SHOWERS AND STORMS SHOULD DEVELOP
THIS AFTN WITH PLENTY OF INSTABILITY ALONG AND AHEAD OF THE FRONT.
A SHORTWAVE OVER SWRN MO WILL ALSO BE MOVING NEWD THROUGH THE AREA
HELPING TO INITIATE CONVECTION ALONG THE FRONT DESPITE ONLY WEAK
SFC CONVERGENCE. WITH LIMITED COVERAGE OF SHOWERS/STORMS WILL
CONTINUE WITH JUST VCTS IN THE TAFS THIS AFTN. WILL PUT VCTS IN
THE UIN AND COU TAFS EARLY THIS AFTN AND IN THE STL METRO AREA
TAFS LATE THIS AFTN. WITH DIURNAL HEATING CUMULUS CLOUDS SHOULD
CONTINUE TO DEVELOP BECOMING BKN BRIEFLY. SOME POST FRONTAL
CUMULUS OR STRATOCUMULUS CLOUDS OVER NWRN MO MAY ALSO ADVECT SEWD
INTO THE TAF SITES LATE THIS AFTN AND THIS EVNG. MOST OF THIS
SHOULD BE VFR. SWLY SFC WIND WILL VEER AROUND TO A NWLY DIRECTION
AFTER FROPA THIS AFTN AND EARLY THIS EVNG. MODELS DEPICT MOISTURE
AROUND 850 MB AT 06Z MON SO SCT CUMULUS OR STRATOCUMULUS CLOUDS
MAY CONTINUE LATE TGT.

SPECIFICS FOR KSTL...VFR CUMULUS CLOUDS SHOULD CONTINUE TO DEVELOP
THIS AFTN GOING BKN AT TIMES. WILL INCLUDE VCTS IN THE STL TAF
FOR LATE THIS AFTN WITH AT LEAST WIDELY SCATTERED SHRA/TSRA
EXPECTED. W-SWLY SFC WIND WILL VEER AROUND TO A NWLY DIRECTION
LATE THIS AFTN AND EARLY THIS EVNG AFTER FROPA. SCATTERED CUMULUS
OR STRATOCUMULUS CLOUDS WILL CONTINUE TGT WITH POST FRONTAL LOW
LEVEL MOISTURE MOVING THROUGH THE AREA. FEW-SCT DIURNAL CUMULUS
CLOUDS MAY ALSO DEVELOP ON MON WITH N-NWLY SFC WINDS AS A SFC
RIDGE BUILDS SEWD INTO MO BEHIND THE COLD FRONT.

GKS

&&

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

$$

WFO LSX

000
FXUS63 KEAX 201727
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
1227 PM CDT Sun May 20 2012


...UPDATED AVIATION DISCUSSION...


.DISCUSSION...

Upper level troughing has lifted north of the CWA and pushed a
surface boundary into the area from the West early this morning. As
feared earlier, sufficient capping, poor forcing and meager boundary
layer moisture has resulted in little to no precipitation in the
forecast area from this system thus far. Forecast concerns remain
fairly minimal in the short term as high pressure begins to push
southward towards the area.

Today: The aforementioned surface front will steadily move east
southeast thought the morning hours, pushing towards the extreme
southeastern portions of the CWA by mid-day. Isolated showers or
sprinkles will be possible ahead of the front this morning, but most
areas will remain dry. By this afternoon, 850 mb trough axis will
catch up to the cold front and should force convection early this
afternoon. Expecting precip to remain over the extreme southeast
counties, if not completely out of the CWA all together. Otherwise,
surface high pressure will being to filter into the area with
temperatures in the 70s leading to a pleasant day in much of the
area.

Tonight: Clouds will be slow to clear this afternoon thanks in part
to strato-cu development behind the low-level trough. It is still
uncertain if clouds will clear sufficiently for full viewing of the
partial annular eclipse this evening. (beginning around 725pm CST).
Otherwise, pleasant overnight temperatures in the upper 40s to lower
50s will be likely.

Monday-Tuesday: Monday will be one of the more pleasant days of the
past two weeks (and highly enjoyable given the potential heat by the
weekend), as the high pressure center drifts overhead. Afternoon
readings will climb into the middle 70s in most locations with low
relative humidity values.

Winds will turn back to the south southwest by Tuesday, with
temperatures beginning to climb back above seasonal normals. Have
bumped up readings a few degrees as 850 temperatures also increase.

Dux



Medium Range (Wednesday Through Saturday)...

00Z solutions continued the trend of developing a large blocking
high across the mid Mississippi Valley toward the end of the period,
with an equally strong negative height anomaly along the California
coastline.

Remnant lee trough from departing northern stream impulse will
dissipate west of the CWA Wednesday and Thursday, with precipitation
chances generally well north and west of the area. Temperatures
which bottomed out in the early periods, will rebound into the
mid-upper 80s.

By late Thursday, a lee cyclone should develop in ern CO beneath the
mid level inflection point, with a warm front extending ENE along
the southern fringes of the anticyclonic portion of the jet. As
upper level ridging strengthens and expands outward, this warm front
will lift north of the CWA early Friday, effectively ending any
precipitation chances for the area for the foreseeable future.

More importantly, the operational solutions and ensemble members
collectively indicate the near certainty of much above to
potentially record breaking temperatures through the Memorial Day
weekend. Thermal ridging, low dewpoints, recent rainfall deficits,
full sunshine and synoptic placement on the backside of this
sprawling closed mid level height center all suggest that upward
temperature adjustments are again required Day 6/7. In fact, given
recent correlation of 850mb temps and actual highs, the prospect of
mid 20C readings given the other variables is perhaps unnerving with
the outside potential for 95 to 100 degree heat next weekend. This
scenario is justified by the ECMWF which has shown considerable
skill in prediction anomalously warm events for the local area.
Nevertheless, will make smaller incremental adjustments into the
lower 90s. For what its worth, the following are record highs for
Kansas City next weekend...

May 25th (Fri): 92
May 26th (Sat): 92
May 27th (Sun): 94
May 28th (Mon): 93

Bookbinder

&&

.AVIATION...

For the 18Z TAFs...Late this morning a low cloud deck moved into the
terminals with ceilings floating just around the upper the upper end
of MVFR criteria, though as the afternoon grows old expectation are
that the clouds will scatter back out leaving VFR conditions to
prevail over the next 24 hours. Otherwise, look for our breezy north
wind to slowly veer around to the northeast by Monday morning as the
surface high shifts east across the Plains States.

Cutter

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KSGF 201720
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
1220 PM CDT SUN MAY 20 2012

...UPDATE TO SHORT TERM FORECAST AND AVIATION...

.UPDATE...

HAVE UPDATED THE SHORT TERM FORECAST EARLY THIS AFTERNOON TO
ACCOUNT FOR THE LATEST MESOSCALE TRENDS. COLD FRONT CURRENTLY IS
ANALYZED FROM ROUGHLY COFFEVILLE TO JOPLIN TO NEVADA...AND WILL
SLOWLY PUSH SOUTHEAST THROUGH THE AFTERNOON AND EVENING. CHANCES
FOR RAIN/THUNDERSTORMS HAVE PRETTY MUCH ENDED BEHIND THIS
BOUNDARY. CHANCES WILL CONTINUE AHEAD OF IT...THOUGH BEST CHANCES
LOOK TO BE SOUTHEAST OF A BRANSON TO ROLLA LINE...WHERE THE BEST
AXIS OF INSTABILITY HAS DEVELOPED. IN ADDITION TO UPDATES TO
POP/WX...ALSO DROPPED HIGHS A FEW DEGREES ALONG AND WEST OF U.S.
65...WHERE HIGH CLOUD COVER HAS LIMITED HEATING TO SOME DEGREE.

BOXELL

&&

.DISCUSSION...
/ISSUED 320 AM CDT SUN MAY 20 2012/

MAIN FOCUS IN THIS FORECAST PACKAGE WILL DEAL WITH SHOWER AND
THUNDERSTORM POTENTIAL THIS MORNING INTO TONIGHT. THEN ATTENTION
TURNS TO HOT AND DRY CONDITIONS LATE THIS WEEK INTO NEXT WEEKEND.

CURRENTLY...SCATTERED THUNDERSTORMS ARE DEVELOPING ACROSS
FAR SOUTHWESTERN MISSOURI INTO NORTHEASTERN OKLAHOMA EARLY THIS
MORNING. THIS ACTIVITY IS DEVELOPING ALONG A BOUNDARY MOVING WEST TO
EAST ACROSS THE REGION. MODEST ELEVATED INSTABILITY REMAINS ACROSS
THESE AREAS OVER NORTHEASTERN OKLAHOMA INTO WEST CENTRAL MISSOURI
EARLY THIS MORNING. INSTABILITY THEN DROPS OFF QUICKLY TO THE
SOUTHEAST ACROSS MUCH OF THE AREA. WIND SHEAR IS GENERALLY ON THE
WEAKER SIDE TOO. AS A RESULT THESE STORMS ARE REMAINING MORE SHORT
LIVED AND WEAK IN NATURE. OVER THE NEXT COUPLE HOURS EARLY THIS
MORNING...SCATTERED THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE
ACROSS NORTHEASTERN OKLAHOMA INTO WEST CENTRAL MISSOURI...WITH
THIS ACTIVITY WEAKENING AS IT PUSHES FARTHER EAST INTO THE
MISSOURI OZARKS AS THE INSTABILITY WEAKENS. NO SEVERE WEATHER IS
EXPECTED WITH THIS ACTIVITY. BRIEF HEAVY RAINFALL...OCCASIONAL
LIGHTNING STRIKES AND PERHAPS A FEW SMALL HAILSTONES WILL BE
POSSIBLE THROUGH SUNRISE GENERALLY WEST OF AN OSCEOLA TO CASSVILLE
MISSOURI LINE.

THE UPPER LEVEL TROUGH THAT IS PUSHING INTO WESTERN IOWA EARLY
THIS MORNING...WILL CONTINUE TO PUSH TO THE EAST NORTHEAST TODAY.
A COLD FRONT WILL CONTINUE TO PUSH TO THE SOUTHEAST THROUGH THE
REGION. WITH THE HEATING OF THE DAY INSTABILITY SHOULD INCREASE
ENOUGH FOR SCATTERED STORMS TO RE-FIRE ON THE COLD FRONT LATE
THIS MORNING INTO THE AFTERNOON HOURS. IF ENOUGH INSTABILITY CAN
DEVELOP A FEW STRONG STORMS CAPABLE OF PRODUCING NICKEL SIZE HAIL
AND GUSTY WINDS MAY BE POSSIBLE LATE THIS MORNING INTO THIS
AFTERNOON GENERALLY SOUTH OF THE INSTATE 44 CORRIDOR. THIS
ACTIVITY SHOULD PUSH SOUTH AND EAST OF THE AREA BY THE EVENING
HOURS. WIND SHEAR WILL BE WEAK AS THE BETTER DYNAMICS REMAIN TO
THE NORTH WITH THE UPPER LEVEL TROUGH. SO NO WIDESPREAD SEVERE
WEATHER IS EXPECTED AND ANY STRONG STORM POTENTIAL WILL BE
DEPENDENT ON HOW MUCH INSTABILITY CAN DEVELOP AHEAD OF THE FRONT.

ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP BEHIND THE FRONT THIS AFTERNOON AND EVENING AS UPPER LEVEL
ENERGY PASSES TO THE NORTH OF THE AREA. NO SEVERE WEATHER IS
EXPECTED WITH ANY OF THIS ACTIVITY. THE FRONT WILL PUSH SOUTH OF
THE AREA THIS EVENING...WITH THE POST FRONTAL ACTIVITY POSSIBLY
LINGERING ACROSS SOUTHERN MISSOURI INTO THE OVERNIGHT HOURS. BY
SUNRISE MONDAY MORNING ISENTROPIC DOWNGLIDE AND MUCH DRIER AIR
WILL SPREAD INTO THE AREA KEEPING ALL PRECIPITATION CHANCES TO THE
SOUTH OF THE AREA BY MONDAY MORNING.

A COOLER AIRMASS WILL SPREAD INTO THE AREA ON MONDAY AND MONDAY
NIGHT AS HIGHS WILL BE CLOSER TO NORMAL WITH READINGS IN THE 70S. LOWS
MONDAY NIGHT WILL LIKELY COOL INTO THE MIDDLE 50S TO UPPER 40S. A
WARMING TREND WILL THEN BEGIN ON TUESDAY INTO THE END OF THE WEEK
AS UPPER LEVEL RIDGING AND A WARMER AIRMASS SPREAD RIGHT BACK INTO
THE AREA. HIGHS IN THE 80S ARE EXPECTED ON WEDNESDAY AND THURSDAY.
FRIDAY INTO NEXT WEEKEND THE RIDGE WILL STRENGTHEN OVER THE
CENTRAL U.S. WITH SUMMER LIKE CONDITIONS EXPECTED...AS HIGHS ARE
EXPECTED TO WARM INTO THE 90S. AFTER TODAYS RAIN CHANCES...DRY
WEATHER IS EXPECTED THROUGH THE REST OF THE FORECAST PERIOD.

WISE


&&

.AVIATION...

FOR THE 18Z TAFS...

RATHER COMPLEX FORECAST FOR THE TERMINALS THROUGH THE REMAINDER OF
THE DAY TODAY. A SLOW MOVING COLD FRONT WILL SERVE AS THE FOCUS
FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON. THIS FRONT HAS JUST
PASSED JLN...AND THUS HAVE REMOVED TSRA MENTION FROM THAT TAF. FOR
SGF AND BBG...MAINTAINED TEMPO MENTION THROUGH THE AFTERNOON
HOURS. THE FRONT SHOULD CLEAR THE TERMINALS BY EVENING...ENDING
THE THREAT FOR TSRA...AND TURNING WINDS TO THE NORTH.

BOXELL

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KSGF 201314
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
814 AM CDT SUN MAY 20 2012

...UPDATE TO AVIATION...

.DISCUSSION...
/ISSUED 320 AM CDT SUN MAY 20 2012/

MAIN FOCUS IN THIS FORECAST PACKAGE WILL DEAL WITH SHOWER AND
THUNDERSTORM POTENTIAL THIS MORNING INTO TONIGHT. THEN ATTENTION
TURNS TO HOT AND DRY CONDITIONS LATE THIS WEEK INTO NEXT WEEKEND.

CURRENTLY...SCATTERED THUNDERSTORMS ARE DEVELOPING ACROSS
FAR SOUTHWESTERN MISSOURI INTO NORTHEASTERN OKLAHOMA EARLY THIS
MORNING. THIS ACTIVITY IS DEVELOPING ALONG A BOUNDARY MOVING WEST TO
EAST ACROSS THE REGION. MODEST ELEVATED INSTABILITY REMAINS ACROSS
THESE AREAS OVER NORTHEASTERN OKLAHOMA INTO WEST CENTRAL MISSOURI
EARLY THIS MORNING. INSTABILITY THEN DROPS OFF QUICKLY TO THE
SOUTHEAST ACROSS MUCH OF THE AREA. WIND SHEAR IS GENERALLY ON THE
WEAKER SIDE TOO. AS A RESULT THESE STORMS ARE REMAINING MORE SHORT
LIVED AND WEAK IN NATURE. OVER THE NEXT COUPLE HOURS EARLY THIS
MORNING...SCATTERED THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE
ACROSS NORTHEASTERN OKLAHOMA INTO WEST CENTRAL MISSOURI...WITH
THIS ACTIVITY WEAKENING AS IT PUSHES FARTHER EAST INTO THE
MISSOURI OZARKS AS THE INSTABILITY WEAKENS. NO SEVERE WEATHER IS
EXPECTED WITH THIS ACTIVITY. BRIEF HEAVY RAINFALL...OCCASIONAL
LIGHTNING STRIKES AND PERHAPS A FEW SMALL HAILSTONES WILL BE
POSSIBLE THROUGH SUNRISE GENERALLY WEST OF AN OSCEOLA TO CASSVILLE
MISSOURI LINE.

THE UPPER LEVEL TROUGH THAT IS PUSHING INTO WESTERN IOWA EARLY
THIS MORNING...WILL CONTINUE TO PUSH TO THE EAST NORTHEAST TODAY.
A COLD FRONT WILL CONTINUE TO PUSH TO THE SOUTHEAST THROUGH THE
REGION. WITH THE HEATING OF THE DAY INSTABILITY SHOULD INCREASE
ENOUGH FOR SCATTERED STORMS TO RE-FIRE ON THE COLD FRONT LATE
THIS MORNING INTO THE AFTERNOON HOURS. IF ENOUGH INSTABILITY CAN
DEVELOP A FEW STRONG STORMS CAPABLE OF PRODUCING NICKEL SIZE HAIL
AND GUSTY WINDS MAY BE POSSIBLE LATE THIS MORNING INTO THIS
AFTERNOON GENERALLY SOUTH OF THE INSTATE 44 CORRIDOR. THIS
ACTIVITY SHOULD PUSH SOUTH AND EAST OF THE AREA BY THE EVENING
HOURS. WIND SHEAR WILL BE WEAK AS THE BETTER DYNAMICS REMAIN TO
THE NORTH WITH THE UPPER LEVEL TROUGH. SO NO WIDESPREAD SEVERE
WEATHER IS EXPECTED AND ANY STRONG STORM POTENTIAL WILL BE
DEPENDENT ON HOW MUCH INSTABILITY CAN DEVELOP AHEAD OF THE FRONT.

ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP BEHIND THE FRONT THIS AFTERNOON AND EVENING AS UPPER LEVEL
ENERGY PASSES TO THE NORTH OF THE AREA. NO SEVERE WEATHER IS
EXPECTED WITH ANY OF THIS ACTIVITY. THE FRONT WILL PUSH SOUTH OF
THE AREA THIS EVENING...WITH THE POST FRONTAL ACTIVITY POSSIBLY
LINGERING ACROSS SOUTHERN MISSOURI INTO THE OVERNIGHT HOURS. BY
SUNRISE MONDAY MORNING ISENTROPIC DOWNGLIDE AND MUCH DRIER AIR
WILL SPREAD INTO THE AREA KEEPING ALL PRECIPITATION CHANCES TO THE
SOUTH OF THE AREA BY MONDAY MORNING.

A COOLER AIRMASS WILL SPREAD INTO THE AREA ON MONDAY AND MONDAY
NIGHT AS HIGHS WILL BE CLOSER TO NORMAL WITH READINGS IN THE 70S. LOWS
MONDAY NIGHT WILL LIKELY COOL INTO THE MIDDLE 50S TO UPPER 40S. A
WARMING TREND WILL THEN BEGIN ON TUESDAY INTO THE END OF THE WEEK
AS UPPER LEVEL RIDGING AND A WARMER AIRMASS SPREAD RIGHT BACK INTO
THE AREA. HIGHS IN THE 80S ARE EXPECTED ON WEDNESDAY AND THURSDAY.
FRIDAY INTO NEXT WEEKEND THE RIDGE WILL STRENGTHEN OVER THE
CENTRAL U.S. WITH SUMMER LIKE CONDITIONS EXPECTED...AS HIGHS ARE
EXPECTED TO WARM INTO THE 90S. AFTER TODAYS RAIN CHANCES...DRY
WEATHER IS EXPECTED THROUGH THE REST OF THE FORECAST PERIOD.

WISE


&&

.AVIATION...

FOR THE 12Z TAFS...SCATTERED CONVECTION WILL REMAIN POSSIBLE TODAY
AS A COLD FRONT TRACKS SOUTHEAST ACROSS THE FORECAST AREA. HAVE
GENERALLY KEPT CONVECTION IN A TEMPO GROUP FROM THE LATE MORNING
THROUGH THE AFTERNOON HOURS DUE TO THE EXPECTED SCATTERED NATURE
OF THE STORMS. DRIER AIR AND ISENTROPIC DOWNGLIDE EXPECTED DURING
THE EVENING SHOULD END PRECIPITATION CHANCES WITH VFR CONDITIONS
AND LIGHT WINDS DEVELOPING.

LINDENBERG

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 201137
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
637 AM CDT SUN MAY 20 2012

.SYNOPSIS...
ISSUED AT 243 AM CDT SUN MAY 20 2012

A SHORTWAVE TROF IS LOCATED ACROSS THE CENTRAL PLAINS...WITH A
STUBBORN UPPER LEVEL RIDGE PARKED ACROSS THE LOWER OHIO RIVER
VALLEY. AT THE SURFACE...A COLD FRONT EXTENDS FROM WEAK LOW PRESSURE
ACROSS NORTHWEST WISCONSIN...THROUGH SOUTHEAST MINNESOATA...CENTRAL
IOWA AND INTO EASTERN KANSAS/CENTRAL OKLAHOMA.

REGIONAL RADAR SHOWS A SPLATTERING OF REMNANT SHOWERS AND
THUNDERSTORMS FROM DIURNAL CONVECTION ACROSS SOUTHEAST KANSAS AND
OKLAHOMA. OTHERWISE...UPPER LEVEL RIDGE CONTINUES TO BLOCK EASTERN
PROGRESS OF CIRRUS SHIELD TO THE EAST OF THE MISSISSIPPI RIVER
VALLEY.

CVKING

&&

.SHORT TERM...
ISSUED AT 243 AM CDT SUN MAY 20 2012
(TODAY AND TONIGHT)

TEMPERATURE FORECAST A BIT TRICKY TODAY AS LOCATIONS ALONG AND
EAST OF THE MISSISSIPPI RIVER HAVE THE POTENTIAL TO WARM BACK INTO
THE UPPER 80S AND PERHAPS LOWER 90S GIVEN UNSEASONABLY WARM START
AND SUNSHINE THIS MORNING. FURTHER WEST...CLOUD COVER WILL ACT TO
LIMIT DIURNAL TEMPERATURE RISE. THIS SHOULD RESULT IN QUITE A
TEMPERATURE CONTRAST FROM WEST TO EAST.

THE SHORTWAVE TROF SPINNING NORTHEAST INTO THE UPPER MIDWEST WILL
SEND A COLD FRONT SOUTH THROUGH THE CWA THIS AFTERNOON AND EVENING.
SCATTERED CONVECTION IS EXPECTED ALONG AND AHEAD OF THE
FRONT...LARGELY TIED TO DIURNAL INSTABILITY. DEEP LAYER SHEAR
REMAINS WEAK WHICH SHOULD KEEP ANY SEVERE WEATHER REPORTS MARGINAL
AND ISOLATED TO THE STRONGEST STORMS.

UPSTREAM POST FRONTAL OBSERVATIONS ACROSS THE DAKOTAS AND NEBRASKA
INDICATE TEMPERATURES WILL DROP SIGNIFICANTLY TONIGHT AND HAVE
LOWERED THEM ACCORDINGLY.

CVKING

&&

.LONG TERM...
ISSUED AT 243 AM CDT SUN MAY 20 2012
(MONDAY THROUGH HOLIDAY WEEKEND)

HIGH PRESSURE QUICKLY BUILDS INTO THE MIDWEST ON MONDAY WITH MUCH
COOLER TEMPERATURES EXPECTED MONDAY AND MONDAY NIGHT. BUT...AS THE
SURFACE HIGH MOVES EAST OF THE AREA AND UPPER LEVEL RIDGE BEGINS TO
TAKE HOLD OF THE CENTER OF THE CONUS A WARMING TREND WILL COMMENCE
BY MIDWEEK. HAVE INCREASED TEMPERATURES ABOVE GUIDANCE FRIDAY AND
SATURDAY AS THEY ARE BEING SKEWED TOWARD COOLER CLIMO NUMBERS. THE
ECWMF MODEL HAS BEEN CONSISTENT IN FORECASTING 2 METER
TEMPERATURES IN THE MIDDLE TO UPPER 90S FOR THE HOLIDAY WEEKEND AS
A 595 DM UPPER LEVEL HIGH BUILDS ACROSS THE LOWER OHIO RIVER
VALLEY. EXPECT DEWPOINTS WILL MIX OUT EACH AFTERNOON GIVEN HOW DRY
WE HAVE BEEN LATELY AND A FAVORABLE SOUTHWEST FLOW AT THE SURFACE.
SO DON`T EXPECT WE WILL MEET OFFICIAL HEAT INDEX CRITERIA...BUT
IT WILL BE HOT FOR THE UNOFFICIAL START OF SUMMER.

CVKING

&&

.AVIATION...
ISSUED AT 601 AM CDT SUN MAY 20 2012
COLD FRONT OVER NORTHWEST MISSOURI WILL CONTINUE MOVING EAST
THROUGH THE DAY. LOW LEVEL WIND SHEAR IS LIKELY ACROSS CENTRAL AND
NORTHEAST MISSOURI AS WELL AS WEST CENTRAL ILLINOIS FOR THE FIRST
FEW HOURS OF THE MORNING AHEAD OF THE COLD FRONT.  EXPECT ISOLATED
SHOWERS AND POTENTIALLY A THUNDERSTORM OR TWO THROUGH 18Z AHEAD OF
THE FRONT IN CENTRAL AND NORTHEAST MISSOURI. PRECIPITATION
COVERAGE SHOULD INCREASE AFTER 18Z WITH DAYTIME HEATING. THINK
COVERAGE SHOULD BE BETWEEN 30-50 PERCENT AT PEAK BETWEEN 20Z AND
00Z THIS AFTERNOON WITH DIMINISHING COVERAGE DURING THE EVENING.
FLIGHT CONDITIONS WILL REMAIN VFR OUTSIDE OF THUNDERSTORMS.

SPECIFICS FOR KSTL...
COLD FRONT OVER NORTHWEST MISSOURI WILL CONTINUE MOVING EAST
THROUGH THE DAY. THERE MAY BE AN ISOLATED SHOWER OR TWO IN THE
VICINITY OF THE TERMINAL BEFORE 18Z TODAY...BUT THE BEST CHANCES
FOR PRECIP WILL BE DURING PEAK HEATING THIS AFTERNOON AFTER 21Z.
SHOULD SEE STORMS DIMINISH AFTER 00Z AFTER THE FRONT PASSES AND
WE LOSE DAYTIME HEATING. FLIGHT CONDITIONS WILL REMAIN VFR OUTSIDE
OF STORMS.


CARNEY

&&

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

$$

WFO LSX

000
FXUS63 KEAX 200853
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
353 AM CDT Sun May 20 2012

.DISCUSSION...

Upper level troughing has lifted north of the CWA and pushed a
surface boundary into the area from the West early this morning. As
feared earlier, sufficient capping, poor forcing and meager boundary
layer moisture has resulted in little to no precipitation in the forecast
area from this system thus far. Forecast concerns remain fairly
minimal in the short term as high pressure begins to push southward
towards the area.

Today: The aforementioned surface front will steadily move east
southeast thought the morning hours, pushing towards the extreme
southeastern portions of the CWA by mid-day. Isolated showers or
sprinkles will be possible ahead of the front this morning, but most
areas will remain dry. By this afternoon, 850 mb trough axis will
catch up to the cold front and should force convection early this
afternoon. Expecting precip to remain over the extreme southeast
counties, if not completely out of the CWA all together. Otherwise,
surface high pressure will being to filter into the area with
temperatures in the 70s leading to a pleasant day in much of the
area.

Tonight: Clouds will be slow to clear this afternoon thanks in part
to strato-cu development behind the low-level trough. It is still
uncertain if clouds will clear sufficiently for full viewing of the
partial annular eclipse this evening. (beginning around 725pm CST).
Otherwise, pleasant overnight temperatures in the upper 40s to lower
50s will be likely.

Monday-Tuesday: Monday will be one of the more pleasant days of the
past two weeks (and highly enjoyable given the potential heat by the
weekend), as the high pressure center drifts overhead. Afternoon
readings will climb into the middle 70s in most locations with low
relative humidity values.

Winds will turn back to the south southwest by Tuesday, with
temperatures beginning to climb back above seasonal normals. Have
bumped up readings a few degrees as 850 temperatures also increase.

Dux



Medium Range (Wednesday Through Saturday)...

00Z solutions continued the trend of developing a large blocking
high across the mid Mississippi Valley toward the end of the period,
with an equally strong negative height anomaly along the California
coastline.

Remnant lee trough from departing northern stream impulse will
dissipate west of the CWA Wednesday and Thursday, with precipitation
chances generally well north and west of the area. Temperatures
which bottomed out in the early periods, will rebound into the
mid-upper 80s.

By late Thursday, a lee cyclone should develop in ern CO beneath the
mid level inflection point, with a warm front extending ENE along
the southern fringes of the anticyclonic portion of the jet. As
upper level ridging strengthens and expands outward, this warm front
will lift north of the CWA early Friday, effectively ending any
precipitation chances for the area for the foreseeable future.

More importantly, the operational solutions and ensemble members
collectively indicate the near certainty of much above to
potentially record breaking temperatures through the Memorial Day
weekend. Thermal ridging, low dewpoints, recent rainfall deficits,
full sunshine and synoptic placement on the backside of this
sprawling closed mid level height center all suggest that upward
temperature adjustments are again required Day 6/7. In fact, given
recent correlation of 850mb temps and actual highs, the prospect of
mid 20C readings given the other variables is perhaps unnerving with
the outside potential for 95 to 100 degree heat next weekend. This
scenario is justified by the ECMWF which has shown considerable
skill in prediction anomalously warm events for the local area.
Nevertheless, will make smaller incremental adjustments into the
lower 90s. For what its worth, the following are record highs for
Kansas City next weekend...

May 25th (Fri): 92
May 26th (Sat): 92
May 27th (Sun): 94
May 28th (Mon): 93

Bookbinder


&&

.AVIATION...

For the 06Z TAFs...Shower and thunderstorm chances continue to
dwindle across northwest Missouri as the better forcing splits around
the region to the north and south. While a few brief showers or
downpours can`t be totally ruled out up until frontal passage around
08Z, the odds for precip are too low to include any kind of mention
in the TAFs. Postfrontal MVFR cigs have been slow to develop, and
think these might remain further north across southern Nebraska where
the majority of rain fell earlier this evening. Any low cigs that do
make it this far south will lift and scatter through the late morning
hours, with VFR the rule through the afternoon.

Hawblitzel

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KSGF 200824
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
324 AM CDT SUN MAY 20 2012

.DISCUSSION...
/ISSUED 320 AM CDT SUN MAY 20 2012/

MAIN FOCUS IN THIS FORECAST PACKAGE WILL DEAL WITH SHOWER AND
THUNDERSTORM POTENTIAL THIS MORNING INTO TONIGHT. THEN ATTENTION
TURNS TO HOT AND DRY CONDITIONS LATE THIS WEEK INTO NEXT WEEKEND.

CURRENTLY...SCATTERED THUNDERSTORMS ARE DEVELOPING ACROSS
FAR SOUTHWESTERN MISSOURI INTO NORTHEASTERN OKLAHOMA EARLY THIS
MORNING. THIS ACTIVITY IS DEVELOPING ALONG A BOUNDARY MOVING WEST TO
EAST ACROSS THE REGION. MODEST ELEVATED INSTABILITY REMAINS ACROSS
THESE AREAS OVER NORTHEASTERN OKLAHOMA INTO WEST CENTRAL MISSOURI
EARLY THIS MORNING. INSTABILITY THEN DROPS OFF QUICKLY TO THE
SOUTHEAST ACROSS MUCH OF THE AREA. WIND SHEAR IS GENERALLY ON THE
WEAKER SIDE TOO. AS A RESULT THESE STORMS ARE REMAINING MORE SHORT
LIVED AND WEAK IN NATURE. OVER THE NEXT COUPLE HOURS EARLY THIS
MORNING...SCATTERED THUNDERSTORMS WILL CONTINUE TO BE POSSIBLE
ACROSS NORTHEASTERN OKLAHOMA INTO WEST CENTRAL MISSOURI...WITH
THIS ACTIVITY WEAKENING AS IT PUSHES FARTHER EAST INTO THE
MISSOURI OZARKS AS THE INSTABILITY WEAKENS. NO SEVERE WEATHER IS
EXPECTED WITH THIS ACTIVITY. BRIEF HEAVY RAINFALL...OCCASIONAL
LIGHTNING STRIKES AND PERHAPS A FEW SMALL HAILSTONES WILL BE
POSSIBLE THROUGH SUNRISE GENERALLY WEST OF AN OSCEOLA TO CASSVILLE
MISSOURI LINE.

THE UPPER LEVEL TROUGH THAT IS PUSHING INTO WESTERN IOWA EARLY
THIS MORNING...WILL CONTINUE TO PUSH TO THE EAST NORTHEAST TODAY.
A COLD FRONT WILL CONTINUE TO PUSH TO THE SOUTHEAST THROUGH THE
REGION. WITH THE HEATING OF THE DAY INSTABILITY SHOULD INCREASE
ENOUGH FOR SCATTERED STORMS TO RE-FIRE ON THE COLD FRONT LATE
THIS MORNING INTO THE AFTERNOON HOURS. IF ENOUGH INSTABILITY CAN
DEVELOP A FEW STRONG STORMS CAPABLE OF PRODUCING NICKEL SIZE HAIL
AND GUSTY WINDS MAY BE POSSIBLE LATE THIS MORNING INTO THIS
AFTERNOON GENERALLY SOUTH OF THE INSTATE 44 CORRIDOR. THIS
ACTIVITY SHOULD PUSH SOUTH AND EAST OF THE AREA BY THE EVENING
HOURS. WIND SHEAR WILL BE WEAK AS THE BETTER DYNAMICS REMAIN TO
THE NORTH WITH THE UPPER LEVEL TROUGH. SO NO WIDESPREAD SEVERE
WEATHER IS EXPECTED AND ANY STRONG STORM POTENTIAL WILL BE
DEPENDENT ON HOW MUCH INSTABILITY CAN DEVELOP AHEAD OF THE FRONT.

ADDITIONAL SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
DEVELOP BEHIND THE FRONT THIS AFTERNOON AND EVENING AS UPPER LEVEL
ENERGY PASSES TO THE NORTH OF THE AREA. NO SEVERE WEATHER IS
EXPECTED WITH ANY OF THIS ACTIVITY. THE FRONT WILL PUSH SOUTH OF
THE AREA THIS EVENING...WITH THE POST FRONTAL ACTIVITY POSSIBLY
LINGERING ACROSS SOUTHERN MISSOURI INTO THE OVERNIGHT HOURS. BY
SUNRISE MONDAY MORNING ISENTROPIC DOWNGLIDE AND MUCH DRIER AIR
WILL SPREAD INTO THE AREA KEEPING ALL PRECIPITATION CHANCES TO THE
SOUTH OF THE AREA BY MONDAY MORNING.

A COOLER AIRMASS WILL SPREAD INTO THE AREA ON MONDAY AND MONDAY
NIGHT AS HIGHS WILL BE CLOSER TO NORMAL WITH READINGS IN THE 70S. LOWS
MONDAY NIGHT WILL LIKELY COOL INTO THE MIDDLE 50S TO UPPER 40S. A
WARMING TREND WILL THEN BEGIN ON TUESDAY INTO THE END OF THE WEEK
AS UPPER LEVEL RIDGING AND A WARMER AIRMASS SPREAD RIGHT BACK INTO
THE AREA. HIGHS IN THE 80S ARE EXPECTED ON WEDNESDAY AND THURSDAY.
FRIDAY INTO NEXT WEEKEND THE RIDGE WILL STRENGTHEN OVER THE
CENTRAL U.S. WITH SUMMER LIKE CONDITIONS EXPECTED...AS HIGHS ARE
EXPECTED TO WARM INTO THE 90S. AFTER TODAYS RAIN CHANCES...DRY
WEATHER IS EXPECTED THROUGH THE REST OF THE FORECAST PERIOD.

WISE

&&

.AVIATION...
/ISSUED 1127 PM CDT SAT MAY 19 2012/

FOR THE 20/0600Z KSGF/KJLN/KBBG TAFS...A COLD FRONT OVER THE
PLAINS WILL SHIFT EAST INTO SOUTHEAST KANSAS AND THE MISSOURI
OZARKS AFTER 12Z. SCATTERED THUNDERSTORMS ARE EXPECTED NEAR THE
FRONT AND HAVE INCLUDED TEMPO GROUPS FOR TSTMS IN ALL
TAFS...MOSTLY AFTER 14Z-16Z. TSTM EVOLUTION AND TIMING/COVERAGE
ALONG THE FRONT ARE IN SOME QUESTION AND WILL WATCH TRENDS INTO
SUNDAY. OUTSIDE OF THUNDERSTORMS EXPECT WINDS TO GRADUALLY VEER AS
THE FRONT APPROACHES...FINALLY SHIFTING TO THE NNW LATE IN THE TAF
PERIOD. FLIGHT CAT: GENERALLY VFR WITH MVFR/LOCALIZED IFR
(VISIBILITY IN HEAVY RAIN) WITH TSTMS...MAINLY DURING DAYLIGHT
HOURS ON SUNDAY.

DSA


&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 200746
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
246 AM CDT SUN MAY 20 2012

.SYNOPSIS...
ISSUED AT 243 AM CDT SUN MAY 20 2012

A SHORTWAVE TROF IS LOCATED ACROSS THE CENTRAL PLAINS...WITH A
STUBBORN UPPER LEVEL RIDGE PARKED ACROSS THE LOWER OHIO RIVER
VALLEY. AT THE SURFACE...A COLD FRONT EXTENDS FROM WEAK LOW PRESSURE
ACROSS NORTHWEST WISCONSIN...THROUGH SOUTHEAST MINNESOATA...CENTRAL
IOWA AND INTO EASTERN KANSAS/CENTRAL OKLAHOMA.

REGIONAL RADAR SHOWS A SPLATTERING OF REMNANT SHOWERS AND
THUNDERSTORMS FROM DIURNAL CONVECTION ACROSS SOUTHEAST KANSAS AND
OKLAHOMA. OTHERWISE...UPPER LEVEL RIDGE CONTINUES TO BLOCK EASTERN
PROGRESS OF CIRRUS SHIELD TO THE EAST OF THE MISSISSIPPI RIVER
VALLEY.

CVKING

&&

.SHORT TERM...
ISSUED AT 243 AM CDT SUN MAY 20 2012
(TODAY AND TONIGHT)

TEMPERATURE FORECAST A BIT TRICKY TODAY AS LOCATIONS ALONG AND
EAST OF THE MISSISSIPPI RIVER HAVE THE POTENTIAL TO WARM BACK INTO
THE UPPER 80S AND PERHAPS LOWER 90S GIVEN UNSEASONABLY WARM START
AND SUNSHINE THIS MORNING. FURTHER WEST...CLOUD COVER WILL ACT TO
LIMIT DIURNAL TEMPERATURE RISE. THIS SHOULD RESULT IN QUITE A
TEMPERATURE CONTRAST FROM WEST TO EAST.

THE SHORTWAVE TROF SPINNING NORTHEAST INTO THE UPPER MIDWEST WILL
SEND A COLD FRONT SOUTH THROUGH THE CWA THIS AFTERNOON AND EVENING.
SCATTERED CONVECTION IS EXPECTED ALONG AND AHEAD OF THE
FRONT...LARGELY TIED TO DIURNAL INSTABILITY. DEEP LAYER SHEAR
REMAINS WEAK WHICH SHOULD KEEP ANY SEVERE WEATHER REPORTS MARGINAL
AND ISOLATED TO THE STRONGEST STORMS.

UPSTREAM POST FRONTAL OBSERVATIONS ACROSS THE DAKOTAS AND NEBRASKA
INDICATE TEMPERATURES WILL DROP SIGNIFICANTLY TONIGHT AND HAVE
LOWERED THEM ACCORDINGLY.

CVKING

&&

.LONG TERM...
ISSUED AT 243 AM CDT SUN MAY 20 2012
(MONDAY THROUGH HOLIDAY WEEKEND)

HIGH PRESSURE QUICKLY BUILDS INTO THE MIDWEST ON MONDAY WITH MUCH
COOLER TEMPERATURES EXPECTED MONDAY AND MONDAY NIGHT. BUT...AS THE
SURFACE HIGH MOVES EAST OF THE AREA AND UPPER LEVEL RIDGE BEGINS TO
TAKE HOLD OF THE CENTER OF THE CONUS A WARMING TREND WILL COMMENCE
BY MIDWEEK. HAVE INCREASED TEMPERATURES ABOVE GUIDANCE FRIDAY AND
SATURDAY AS THEY ARE BEING SKEWED TOWARD COOLER CLIMO NUMBERS. THE
ECWMF MODEL HAS BEEN CONSISTENT IN FORECASTING 2 METER
TEMPERATURES IN THE MIDDLE TO UPPER 90S FOR THE HOLIDAY WEEKEND AS
A 595 DM UPPER LEVEL HIGH BUILDS ACROSS THE LOWER OHIO RIVER
VALLEY. EXPECT DEWPOINTS WILL MIX OUT EACH AFTERNOON GIVEN HOW DRY
WE HAVE BEEN LATELY AND A FAVORABLE SOUTHWEST FLOW AT THE SURFACE.
SO DON`T EXPECT WE WILL MEET OFFICIAL HEAT INDEX CRITERIA...BUT
IT WILL BE HOT FOR THE UNOFFICIAL START OF SUMMER.

CVKING

&&

.AVIATION...
ISSUED AT 1141 PM CDT SAT MAY 19 2012

SELY WINDS WILL PICK UP TO SWLY SHORTLY AFTER SUNRISE. A BRIEF
PERIOD OF HIGHER GUSTS WILL BE POSSIBLE JUST AHEAD OF THE
APPROACHING CDFNT...BUT ATTM...GUSTS HIGHER THAN 20 KTS ARE NOT
ANTICIPATED. TSRA ARE EXPECTED ALONG AND JUST AHEAD OF THE CDFNT
WITH WINDS BECOMING WLY THEN NWLY BEHIND THE FNT.

SPECIFICS FOR KSTL...SELY WINDS WILL PICK UP TO SWLY SHORTLY AFTER SUNRISE.
A BRIEF PERIOD OF HIGHER GUSTS WILL BE POSSIBLE JUST AHEAD OF THE
APPROACHING CDFNT...BUT ATTM...GUSTS HIGHER THAN 20 KTS ARE NOT
ANTICIPATED. TSRA ARE EXPECTED ALONG AND JUST AHEAD OF THE CDFNT
WITH WINDS BECOMING WLY THEN NWLY BEHIND THE FNT.

TILLY

&&

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

$$

WFO LSX

000
FXUS63 KLSX 200452
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1152 PM CDT SAT MAY 19 2012

.UPDATE...
ISSUED AT 932 PM CDT SAT MAY 19 2012

JUST MADE CHANGES WITH THE CLOUD COVER OVER MISSOURI AND PARTS OF
WEST CENTRAL AND SOUTHWEST ILLINOIS. LATEST SURFACE ANALYSIS SHOWS
THIN RIBBON OF 60 DEGREE DEWPOINTS FROM SOUTHEAST NEBRASKA THROUGH
CENTRAL TEXAS. ANOTHER POCKET EXTENDED ACROSS NORTHERN AND CENTRAL
MISSOURI. COLD FRONTAL BOUNDARY CONTINUES TO MOVE EASTWARD AS IT
EXTENDS FROM SOUTHERN MINNESOTA THROUGH NORTHWEST OKLAHOMA.
UPSTAIRS 8H FIELD SHOWS NARROW 8H DEWPT AXIS OF 12C EXTENDING FROM
CENTRAL OKLAHOMA INTO SOUTHERN TEXAS WITH SMALLER VALUES FURTHER
TO THE NORTH. 12C DEWPOINTS MIGHT REACH INTO SOUTHWEST MISSOURI BY
1200 UTC. EXPECT COLD FRONT TO MOVE ACROSS EASTERN MISSOURI
DURING THE LATE AFTERNOON HOURS ON SUNDAY. NAM MIGHT BE A LITTLE FAST
IN COLD FRONTAL POSITION AT 0000 UTC SUNDAY EVENING. SCT TSTMS
ALONG AND AHEAD OF COLD FRONT EXPECTED. GUSTY WINDS LIKELY WITH
SOME OF THE STRONGER STORMS.

PRZYBYLINSKI

&&

.SHORT TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(TONIGHT AND SUNDAY)

WITH A GOOD DIURNAL CUMULUS FIELD ACROSS MUCH OF THE AREA AND
UNSTABLE CONDITIONS COULD NOT RULE OUT AN ISOLATED SHOWER/STORM
ESPECIALLY ACROSS THE OZARKS LATE THIS AFTN/EARLY THIS EVNG...BUT
FOR NOW KEPT FORECAST DRY WITH LITTLE IF ANY FORCING OR SFC
BOUNDARIES TO INITIATE CONVECTION.  THE LOW LEVEL CLOUD FIELD SHOULD
DISSIPATE LATER THIS EVNG WITH LOSE OF DAYTIME HEATING.  MID-HIGH
LEVEL CLOUDINESS WILL INCREASE OVER THE AREA TGT WITH SW FLOW
SHORTWAVES APPROACHING OUR AREA AND INCREASING LOW-MID LEVEL WAA
AHEAD OF AN APPROACHING 850 MB TROUGH.  KEPT THE FORECAST DRY TGT AS
THE GFS MODEL WAS THE ONLY OPERATIONAL MODEL WHICH DEVELOPS ANY QPF
IN OUR AREA WELL AHEAD OF THE APPROACHING COLD FRONT NOW EXTENDING
FROM A WEAK SFC LOW OVER NRN MN SW THROUGH THE OK AND TX PNHDLS.
THIS COLD FRONT WILL DROP SEWD THROUGH MUCH OF OUR AREA ON SUN AS AN
UPPER LEVEL TROUGH MOVES EWD THROUGH THE NRN PLAINS.  AT LEAST
SCATTERED CONVECTION IS EXPECTED ALONG AND JUST AHEAD OF THIS FRONT
MAINLY ACROSS NERN AND CNTRL MO SUN MRNG AND ACROSS THE ENTIRE AREA
SUN AFTN. ALTHOUGH THERE WILL BE PLENTY OF LOW LEVEL MOISTURE AND
INSTABILITY SUN AFTN THE SFC CONVERGENCE ALONG THE FRONT LOOKS
RELATIVELY WEAK AND THE LOW-MID LEVEL SHEAR LOOKS WEAK AS WELL SO
ANY SEVERE OR NEAR SEVERE STORMS SHOULD BE SHORT LIVED AND
ISOLATED.  WITH INCREASED CLOUD COVER AND SCATTERED PRECIPITATION
HIGH TEMPERATURES SHOULD BE COOLER ON SUN MAINLY ACROSS NERN AND
CNTRL MO BEHIND THE COLD FRONT...BUT STILL WELL ABOVE NORMAL FROM ST
LOUIS S AND E AHEAD OF THE COLD FRONT.

GKS

&&

.LONG TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(SUNDAY NIGHT TO NEXT SATURDAY)

GFS/NAM SEEM TO BE IN REASONABLE AGREEMENT OVERALL IN MOVING THE
SHOWERS AND THUNDERSTORMS OUT OF THE AREA ON SUNDAY NIGHT.  WHILE
DETAILS ARE MESSY BECAUSE OF THE CONVECTIVE FEEDBACK...PARTICULARLY
IN THE GFS...SURFACE COLD FRONT THAT WILL EXTEND FROM CNTRL MO INTO
W CNTRL IL AT 00Z SUNDAY EVENING SHOULD MOVE SOUTHEAST AND CLEAR THE
CWA SHORTLY AFTER MIDNIGHT.  THEREAFTER IT STILL LOOKS LIKE DRY
WEATHER WILL PREVAIL THROUGH NEXT WEEKEND.  THE GLOBAL MODELS ARE IN
GOOD AGREEMENT THAT UPPER RIDGE WILL BUILD BACK INTO THE AREA AND
ANY FRONTS WILL REMAIN WELL NORTH OF THE CWA.

MOS TEMPERATURES ARE IN GOOD AGREEMENT THAT MONDAY AND TUESDAY`S
HIGHS WILL CLIMB TO AROUND NORMAL FOR MID MAY AS SURFACE WINDS
REMAIN OUT OF THE NORTH.  TEMPERATURES WILL THEN JUMP BACK WELL
ABOVE NORMAL MIDWEEK INTO SATURDAY AS DOMINANT SURFACE WIND FLOW
BECOMES SOUTHERLY WITH APPRECIABLE SUNSHINE. 850MB TEMPERATURES
WILL CLIMB UP TO AROUND 20C THURSDAY-SATURDAY WHICH SUPPORTS
SURFACE TEMPERATURES OF 90F OR GREATER.

BRITT

&&

.AVIATION...
ISSUED AT 1141 PM CDT SAT MAY 19 2012

SELY WINDS WILL PICK UP TO SWLY SHORTLY AFTER SUNRISE. A BRIEF
PERIOD OF HIGHER GUSTS WILL BE POSSIBLE JUST AHEAD OF THE
APPROACHING CDFNT...BUT ATTM...GUSTS HIGHER THAN 20 KTS ARE NOT
ANTICIPATED. TSRA ARE EXPECTED ALONG AND JUST AHEAD OF THE CDFNT
WITH WINDS BECOMING WLY THEN NWLY BEHIND THE FNT.

SPECIFICS FOR KSTL...SELY WINDS WILL PICK UP TO SWLY SHORTLY AFTER SUNRISE.
A BRIEF PERIOD OF HIGHER GUSTS WILL BE POSSIBLE JUST AHEAD OF THE
APPROACHING CDFNT...BUT ATTM...GUSTS HIGHER THAN 20 KTS ARE NOT
ANTICIPATED. TSRA ARE EXPECTED ALONG AND JUST AHEAD OF THE CDFNT
WITH WINDS BECOMING WLY THEN NWLY BEHIND THE FNT.

TILLY

&&

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

$$

WFO LSX

000
FXUS63 KEAX 200449
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
1149 PM CDT Sat May 19 2012


...UPDATED AVIATION DISCUSSION...


.DISCUSSION...

Short Range (Today through Monday)...

This morning showers and thunderstorms developed on the edge of the
low level jet, where moisture convergence was maximized, though by
noon the storms had mostly dissipated as the jet mixed out with the
expanding boundary layer, leaving only isolated sprinkles and a
modest mid-level cloud deck moving east into Missouri. Farther
afield, a cold front is noted stretched from Minnesota south
southwest through eastern Nebraska, central Kansas, into the
panhandles of Oklahoma and Texas, and it will be this fronts
movement through Kansas and Missouri tonight into Sunday which will
be the focus for stormy activity. Otherwise, of note is a shortwave
currently exiting eastern Colorado, which will lift towards the
upper Great Lakes overnight and through Sunday. This movement will
help push the cold front wallowing to our west through eastern
Kansas and western Missouri late tonight through Sunday.

Tonight and Sunday...afternoon SPC analysis shows shows 1500-2000
J/KG of MLCAPE across east central Kansas and northwest Missouri
this afternoon, but it also shows MLCIN greater than -150 J/KG which
seems reasonable given the local ascent soundings from 1830Z at the
KMCI terminal, which shows a decent dry layer present between 850mb
and 600mb. Add to this the cloud cover across the region due to this
mornings fading storms, and convective initiation looks like it will
have to wait till late this afternoon to occur, likely in the
vicinity of the front which will still be in north central to
northeast Kansas. Moisture will be a somewhat limiting factor as
dewpoints have struggled to rise much beyond 60 degrees, with many
locations not even achieving that. Shear, especially in the cloud
baring layers away from the immediate vicinity of the front, is not
particularly high in the pre-frontal environment, so expectations
are that storms will have a very low potential for severe weather
outside of the far northwest corner of Missouri and adjacent areas
of extreme northeast Kansas, where large hail and strong winds would
be possible as the front arrives coincident with any thunderstorms.
Verity of models all share this outlook on the forecast, though they
also share an expectation that the main focus for activity will
shift to our north, as a jet streak rounds to shortwave and heads
northeast, and south, as what little low level jet is present late
tonight enhances convergences across south central Kansas and
Oklahoma. So, while confidence that some precipitation will develop
and fall in the forecast area tonight, the advertised scattered
nature of the storms that will move in seem to warrant only a
chance POP for the overnight hours. Otherwise, storms may persist
through Sunday, shifting east into areas from northeast to central
and west central Missouri during the afternoon hours. While shear is
better in the post-frontal environment, instability will not be, so
no severe thunderstorm activity is expected.

Otherwise, looking at Monday, expect temperatures to range around to
just below normal for the day (which in later half of May means
beautiful conditions) as mostly sunny skies and north to northeast
winds make for a pleasant start to the work week.

Cutter


Medium Range (Tuesday through Saturday)...

This extended period of the forecast will be marked by dry
conditions and temperatures jumping to 10F+ degrees above normal.
Through the middle of this upcoming week, an area of surface high
pressure will shift just east of the area, dominating much of the
eastern and southeastern U.S. This surface pattern will result in a steady
southerly flow into the region, which will help support the rise in
temperatures. Tuesday into Wednesday, models show an area of low
pressure moving eastward into the Northern Plains and sagging
southward into the western part of the Central Plains. However,
thanks to an upper level ridge that will build in across much of the
eastern CONUS, this surface low will essentially be blocked from
entering into the forecast area due to this strong ridge. As a
result, any precipitation associated with this area of low pressure
looks to stay north and west of the region. Models show this
upper ridge remaining firmly in place through the end of the period.
One discrepancy amongst the models comes into play for the end of
the week with regards to whether or not the potential for
precipitation exists. GFS shows an upper level trough dropping
southward enough into the extreme Northern Plains that it may push
some of the precipitation from the surface low down into extreme
northeast Kansas and extreme northwest Missouri. Other models though
keep the trough in southern Canada which would limit the potential
for the precipitation to be pushed southward into the area. As a
result, have nothing more than slight chance pops Thursday night and
Friday across the extreme northwest corner of the forecast area.

As for temperatures, with the persistent southerly flow in place,
conditions on Tuesday will be a few degrees above normal and the
warming trend will continue through the period. Mild conditions are
expected for the latter half of the week and into next weekend as
temperatures steadily soar into the middle to upper 80s -- and
possibly into the lower 90s.

ACH

&&

.AVIATION...

For the 06Z TAFs...Shower and thunderstorm chances continue to
dwindle across northwest Missouri as the better forcing splits around
the region to the north and south. While a few brief showers or
downpours can`t be totally ruled out up until frontal passage around
08Z, the odds for precip are too low to include any kind of mention
in the TAFs. Postfrontal MVFR cigs have been slow to develop, and
think these might remain further north across southern Nebraska where
the majority of rain fell earlier this evening. Any low cigs that do
make it this far south will lift and scatter through the late morning
hours, with VFR the rule through the afternoon.

Hawblitzel

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KSGF 200429
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
1129 PM CDT SAT MAY 19 2012

...UPDATE TO AVIATION...

.UPDATE...
/ISSUED 1120 PM CDT SAT MAY 19 2012/

MADE SOME MINOR ADJUSTMENTS TO RAIN/TSTM CHANCES OVER THE FAR
WESTERN CWFA OVERNIGHT. SCATTERED CONVECTION OVER SE KS IS
WEAKENING ATTM. MU CAPES ARE PROGGED TO CONTINUE TO WEAKEN
GRADUALLY OVERNIGHT...BUT 500-1000 J/KG ENOUGH TO SUPPORT ISOLD-
WDLY SCT SHRA/TSRA AS THE THE FRONT OVER THE PLAINS APPROACHES.
WITH THE SHORTWAVE OVER NEB STARTING TO SHIFT NORTHEAST...VERTICAL
SHEAR IS ALSO EXPECTED TO GRADUALLY WEAKEN TONIGHT INTO SUNDAY.
GENERAL WORDING OF THE HWO STILL LOOKS GOOD...BUT WILL ADJUST
OVERNIGHT TIMES TO BETTER FIT TRENDS.

DSA

&&

.DISCUSSION...
//315 PM CDT SAT MAY 19 2012//
THE MAIN FORECAST CONCERN FOR THE NEXT 48 HOURS WILL BE
THUNDERSTORM CHANCES AS A COLD FRONT SLOWLY PUSHES THROUGH THE
REGION. TEMPERATURES WILL THEN TAKE CENTER STAGE STARTING AROUND
THE MIDDLE OF NEXT WEEK.

CURRENTLY...WATER VAPOR IMAGERY DEPICTS UPPER LEVEL SHORT WAVE
ENERGY TRACKING FROM NORTHEASTERN COLORADO INTO THE WESTERN CORN
BELT REGION. AT THE SURFACE...LOW PRESSURE WAS ANALYZED FAIRLY
CLOSE TO RUSSEL KANSAS. A DRY LINE TRAILED THE LOW DOWN INTO
NORTHWESTERN OKLAHOMA...WITH A COLD FRONT ON THE VERGE OF
OVERTAKING THE DRY LINE. OTHER THAN SOME MID LEVEL ECHOES OVER
WESTERN MISSOURI...THE REGIONAL RADAR COMPOSITE IS QUIET UNTIL YOU
GET BACK TO THE COOLING MID LEVELS DIRECTLY BENEATH THAT MID LEVEL
SHORT WAVE TROUGH.

THAT UPPER LEVEL WAVE WILL CONTINUE TO TRACK NORTHEAST TOWARDS THE
WESTERN GREAT LAKES FROM TONIGHT INTO SUNDAY MORNING. AS THE MAIN
MID LEVEL HEIGHT FALLS OVERSPREAD THE CENTRAL PLAINS LATER THIS
AFTERNOON AND THIS EVENING...THAT COLD FRONT WILL BEGIN TO DRIVE
EAST. THIS SHOULD BE PLENTY OF FORCING TO INITIATE CONVECTION FROM
CENTRAL KANSAS INTO NORTHWESTERN OKLAHOMA. AS WE HEAD INTO LATER
TONIGHT...THAT FRONT WILL BEGIN TO APPROACH SOUTHEASTERN KANSAS
AND WEST CENTRAL MISSOURI. WHILE THE MOST VIGOROUS CONVECTION WILL
OCCUR TO OUR WEST THIS EVENING...A FEW SHOWERS AND THUNDERSTORMS
SHOULD IMPACT AREAS GENERALLY ALONG AND WEST OF THE HIGHWAY 71
CORRIDOR LATE TONIGHT. NO SEVERE STORMS ARE EXPECTED GIVEN THE
LACK OF INSTABILITY AND SHEAR.

THAT FRONT WILL THEN CONTINUE TO PROGRESS EAST INTO THE OZARKS ON
SUNDAY. IT WILL BEGIN TO LOSE FORWARD MOMENTUM AS THE MAIN HEIGHT
FALLS PASS TO OUR NORTH. NEVERTHELESS...WEAK FORCING ALONG THE
FRONT WILL BE ENOUGH FOR SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. WHILE MODERATE AMOUNTS OF INSTABILITY WILL BE
PRESENT...SHEAR WILL BE WEAK. WILL CONTINUE WITH A SUB SEVERE WIND
AND HAIL THREAT IN THE HAZARDOUS WEATHER OUTLOOK...BUT THE
PROSPECT FOR SEVERE STORMS LOOKS VERY LOW.

THE NEXT FORECAST CONCERN THEN BECOMES WHEN THE THREAT FOR
THUNDERSTORMS WILL END...ESPECIALLY ACROSS SOUTHERN MISSOURI.
WHILE THE SURFACE FRONT WILL CLEAR THE STATE LINE...BOTH THE NAM
AND GFS HINT AT SLIGHTLY ELEVATED SLUGS OF CONVERGENCE INTO AT
LEAST MONDAY MORNING. LIFTING PARCELS IN THE 850 TO 750 LAYER DOES
INDEED YIELD LITTLE IN THE WAY OF INHIBITION. THUS...WILL HOLD ON
TO 20 TO 30 POPS ACROSS SOUTHERN MISSOURI INTO MONDAY MORNING.

WE ARE THEN LOOKING AT AN EXTENDED DRY PERIOD AS A PATTERN CHANGE
COMMENCES. A SLIGHTLY COOLER AIR MASS WILL INITIALLY FILTER INTO
THE REGION TO START NEXT WORK WEEK. OVERALL...NEAR NORMAL
TEMPERATURES ARE EXPECTED MONDAY AND TUESDAY.

LONG WAVE CHARTS THEN BEGIN TO AMPLIFY AND RETROGRADE A TROUGH
OVER WESTERN NORTH AMERICA LATER NEXT WEEK. WAVE FIVE CHARTS
CONTINUE TO INDICATE THAT THE TROUGH AXIS WILL EXTEND FROM THE
CANADIAN PRAIRIES...SOUTHWEST TOWARDS THE SOUTHERN CALIFORNIA
COAST. ONE CONCERNING TREND IS THAT THE LONG WAVE CHARTS HAVE
SHOWN A STRENGTHENING TREND WITH AN UPPER LEVEL HIGH CENTERED NEAR
THE CAROLINA COAST. THIS REGIME WOULD FAVOR A STRENGTHENING
SYNOPTIC SCALE UPPER LEVEL HIGH ACROSS THE MID MISSISSIPPI AND
OHIO VALLEY REGION. THE RESULT FOR OUR SENSIBLE WEATHER WOULD BE
DRY AND HOT CONDITIONS STARTING FROM LATER NEXT WEEK THROUGH AT
LEAST NEXT WEEKEND.

IN LIGHT OF THIS...HAVE BUMPED UP EXPECTED HIGHS INTO THE UPPER
80S AND LOWER 90S AREA WIDE. IF 85O MB TEMPERATURE PROGS FROM THE
ECMWF ARE CORRECT...MOST AREAS WILL BE IN THE 90S NEXT WEEKEND.
ONE PIECE OF GOOD NEWS IS THAT MANY AREAS OF THE OZARKS SHOULD SEE
GOOD MIXING. THUS...DEW POINTS AND RELATIVE HUMIDITIES SHOULD
REMAIN FAIRLY LOW. SLIGHTLY HIGHER DEW POINTS ARE EXPECTED FROM
THE HIGHWAY 71 CORRIDOR INTO THE TRUMAN LAKE REGION.

SCHAUMANN


&&

.AVIATION...
/ISSUED 1127 PM CDT SAT MAY 19 2012/

FOR THE 20/0600Z KSGF/KJLN/KBBG TAFS...A COLD FRONT OVER THE
PLAINS WILL SHIFT EAST INTO SOUTHEAST KANSAS AND THE MISSOURI
OZARKS AFTER 12Z. SCATTERED THUNDERSTORMS ARE EXPECTED NEAR THE
FRONT AND HAVE INCLUDED TEMPO GROUPS FOR TSTMS IN ALL
TAFS...MOSTLY AFTER 14Z-16Z. TSTM EVOLUTION AND TIMING/COVERAGE
ALONG THE FRONT ARE IN SOME QUESTION AND WILL WATCH TRENDS INTO
SUNDAY. OUTSIDE OF THUNDERSTORMS EXPECT WINDS TO GRADUALLY VEER AS
THE FRONT APPROACHES...FINALLY SHIFTING TO THE NNW LATE IN THE TAF
PERIOD. FLIGHT CAT: GENERALLY VFR WITH MVFR/LOCALIZED IFR
(VISIBILITY IN HEAVY RAIN) WITH TSTMS...MAINLY DURING DAYLIGHT
HOURS ON SUNDAY.

DSA


&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 200249
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
949 PM CDT SAT MAY 19 2012

.UPDATE...
ISSUED AT 932 PM CDT SAT MAY 19 2012
ISSUED AT 637 PM CDT SAT MAY 19 2012

JUST MADE CHANGES WITH THE CLOUD COVER OVER MISSOURI AND PARTS OF
WEST CENTRAL AND SOUTHWEST ILLINOIS. LATEST SURFACE ANALYSIS SHOWS
THIN RIBBON OF 60 DEGREE DEWPOINTS FROM SOUTHEAST NEBRASKA THROUGH
CENTRAL TEXAS. ANOTHER POCKET EXTENDED ACROSS NORTHERN AND CENTRAL
MISSOURI. COLD FRONTAL BOUNDARY CONTINUES TO MOVE EASTWARD AS IT
EXTENDS FROM SOUTHERN MINNESOTA THROUGH NORTHWEST OKLAHOMA.
UPSTAIRS 8H FIELD SHOWS NARROW 8H DEWPT AXIS OF 12C EXTENDING FROM
CENTRAL OKLAHOMA INTO SOUTHERN TEXAS WITH SMALLER VALUES FURTHER
TO THE NORTH. 12C DEWPOINTS MIGHT REACH INTO SOUTHWEST MISSOURI BY
1200 UTC. EXPECT COLD FRONT TO MOVE ACROSS EASTERN MISSOURI
DURING THE LATE AFTERNOON HOURS ON SUNDAY. NAM MIGHT BE A LITTLE FAST
IN COLD FRONTAL POSITION AT 0000 UTC SUNDAY EVENING. SCT TSTMS
ALONG AND AHEAD OF COLD FRONT EXPECTED. GUSTY WINDS LIKELY WITH
SOME OF THE STRONGER STORMS.

PRZYBYLINSKI

&&

.SHORT TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(TONIGHT AND SUNDAY)

WITH A GOOD DIURNAL CUMULUS FIELD ACROSS MUCH OF THE AREA AND
UNSTABLE CONDITIONS COULD NOT RULE OUT AN ISOLATED SHOWER/STORM
ESPECIALLY ACROSS THE OZARKS LATE THIS AFTN/EARLY THIS EVNG...BUT
FOR NOW KEPT FORECAST DRY WITH LITTLE IF ANY FORCING OR SFC
BOUNDARIES TO INITIATE CONVECTION.  THE LOW LEVEL CLOUD FIELD SHOULD
DISSIPATE LATER THIS EVNG WITH LOSE OF DAYTIME HEATING.  MID-HIGH
LEVEL CLOUDINESS WILL INCREASE OVER THE AREA TGT WITH SW FLOW
SHORTWAVES APPROACHING OUR AREA AND INCREASING LOW-MID LEVEL WAA
AHEAD OF AN APPROACHING 850 MB TROUGH.  KEPT THE FORECAST DRY TGT AS
THE GFS MODEL WAS THE ONLY OPERATIONAL MODEL WHICH DEVELOPS ANY QPF
IN OUR AREA WELL AHEAD OF THE APPROACHING COLD FRONT NOW EXTENDING
FROM A WEAK SFC LOW OVER NRN MN SW THROUGH THE OK AND TX PNHDLS.
THIS COLD FRONT WILL DROP SEWD THROUGH MUCH OF OUR AREA ON SUN AS AN
UPPER LEVEL TROUGH MOVES EWD THROUGH THE NRN PLAINS.  AT LEAST
SCATTERED CONVECTION IS EXPECTED ALONG AND JUST AHEAD OF THIS FRONT
MAINLY ACROSS NERN AND CNTRL MO SUN MRNG AND ACROSS THE ENTIRE AREA
SUN AFTN. ALTHOUGH THERE WILL BE PLENTY OF LOW LEVEL MOISTURE AND
INSTABILITY SUN AFTN THE SFC CONVERGENCE ALONG THE FRONT LOOKS
RELATIVELY WEAK AND THE LOW-MID LEVEL SHEAR LOOKS WEAK AS WELL SO
ANY SEVERE OR NEAR SEVERE STORMS SHOULD BE SHORT LIVED AND
ISOLATED.  WITH INCREASED CLOUD COVER AND SCATTERED PRECIPITATION
HIGH TEMPERATURES SHOULD BE COOLER ON SUN MAINLY ACROSS NERN AND
CNTRL MO BEHIND THE COLD FRONT...BUT STILL WELL ABOVE NORMAL FROM ST
LOUIS S AND E AHEAD OF THE COLD FRONT.

GKS

&&

.LONG TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(SUNDAY NIGHT TO NEXT SATURDAY)

GFS/NAM SEEM TO BE IN REASONABLE AGREEMENT OVERALL IN MOVING THE
SHOWERS AND THUNDERSTORMS OUT OF THE AREA ON SUNDAY NIGHT.  WHILE
DETAILS ARE MESSY BECAUSE OF THE CONVECTIVE FEEDBACK...PARTICULARLY
IN THE GFS...SURFACE COLD FRONT THAT WILL EXTEND FROM CNTRL MO INTO
W CNTRL IL AT 00Z SUNDAY EVENING SHOULD MOVE SOUTHEAST AND CLEAR THE
CWA SHORTLY AFTER MIDNIGHT.  THEREAFTER IT STILL LOOKS LIKE DRY
WEATHER WILL PREVAIL THROUGH NEXT WEEKEND.  THE GLOBAL MODELS ARE IN
GOOD AGREEMENT THAT UPPER RIDGE WILL BUILD BACK INTO THE AREA AND
ANY FRONTS WILL REMAIN WELL NORTH OF THE CWA.

MOS TEMPERATURES ARE IN GOOD AGREEMENT THAT MONDAY AND TUESDAY`S
HIGHS WILL CLIMB TO AROUND NORMAL FOR MID MAY AS SURFACE WINDS
REMAIN OUT OF THE NORTH.  TEMPERATURES WILL THEN JUMP BACK WELL
ABOVE NORMAL MIDWEEK INTO SATURDAY AS DOMINANT SURFACE WIND FLOW
BECOMES SOUTHERLY WITH APPRECIABLE SUNSHINE. 850MB TEMPERATURES
WILL CLIMB UP TO AROUND 20C THURSDAY-SATURDAY WHICH SUPPORTS
SURFACE TEMPERATURES OF 90F OR GREATER.

BRITT

&&

.AVIATION...
ISSUED AT 657 PM CDT SAT MAY 19 2012

VFR AND DRY CONDITIONS EXPECTED TO CONTINUE OVERNIGHT. WINDS WILL
BACK THIS EVENING AND VEER TO SWLY SUN MORNING AHEAD OF AN
APPROACHING CDFNT. THIS FNT WILL BRING TSRA TO TERMINALS LATE
MORNING THRU MUCH OF THE AFTERNOON HRS. THE TIMING OF THE TSRA MAY
NEED TO BE ADJUSTED WITH FUTURE UPDATES...BUT APPEARS TO BE ON
TRACK ATTM. WINDS WILL BECOME WLY TO NWLY BEHIND THE FNT LATE SUN
AFTERNOON INTO THE EVENING.

TILLY

&&

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

$$

WFO LSX

000
FXUS63 KEAX 200247
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
947 PM CDT Sat May 19 2012

.UPDATE...
/938 PM CDT Sat May 19 2012/

00Z TOP sounding and latest AMDAR soundings out of MCI show quite a
bit of low-level dry air and convective inhibition which has made it
very difficult for convection to survive into eastern KS this evening.
As we continue to lose daytime heating this evening, convective
potential will become more dependent on the placement of the 850 hPa
jet and the slightly enhanced elevated theta-e that it feeds into
these storms. Latest RUC analysis shows a somewhat split pattern to
the LLJ with a northern focus near Omaha and a secondary maximum over
southern KS. Not surprisingly the best convective development has
been focused across these areas this evening. Still cannot rule out
some convective development in between these two areas later tonight
as the two jet maxima merge toward 06Z. Would need quite a bit of
theta-e advection at 850 hPa to break the capping inversion that is
evident on the 00Z TOP sounding, so will keep PoPs limited to low
chance overnight. Any storm that does develop over our area should
remain sub severe as better midlevel winds remain to the north and
west of the forecast area.

Hawblitzel

&&

.DISCUSSION...

Short Range (Today through Monday)...

This morning showers and thunderstorms developed on the edge of the
low level jet, where moisture convergence was maximized, though by
noon the storms had mostly dissipated as the jet mixed out with the
expanding boundary layer, leaving only isolated sprinkles and a
modest mid-level cloud deck moving east into Missouri. Farther
afield, a cold front is noted stretched from Minnesota south
southwest through eastern Nebraska, central Kansas, into the
panhandles of Oklahoma and Texas, and it will be this fronts
movement through Kansas and Missouri tonight into Sunday which will
be the focus for stormy activity. Otherwise, of note is a shortwave
currently exiting eastern Colorado, which will lift towards the
upper Great Lakes overnight and through Sunday. This movement will
help push the cold front wallowing to our west through eastern
Kansas and western Missouri late tonight through Sunday.

Tonight and Sunday...afternoon SPC analysis shows shows 1500-2000
J/KG of MLCAPE across east central Kansas and northwest Missouri
this afternoon, but it also shows MLCIN greater than -150 J/KG which
seems reasonable given the local ascent soundings from 1830Z at the
KMCI terminal, which shows a decent dry layer present between 850mb
and 600mb. Add to this the cloud cover across the region due to this
mornings fading storms, and convective initiation looks like it will
have to wait till late this afternoon to occur, likely in the
vicinity of the front which will still be in north central to
northeast Kansas. Moisture will be a somewhat limiting factor as
dewpoints have struggled to rise much beyond 60 degrees, with many
locations not even achieving that. Shear, especially in the cloud
baring layers away from the immediate vicinity of the front, is not
particularly high in the pre-frontal environment, so expectations
are that storms will have a very low potential for severe weather
outside of the far northwest corner of Missouri and adjacent areas
of extreme northeast Kansas, where large hail and strong winds would
be possible as the front arrives coincident with any thunderstorms.
Verity of models all share this outlook on the forecast, though they
also share an expectation that the main focus for activity will
shift to our north, as a jet streak rounds to shortwave and heads
northeast, and south, as what little low level jet is present late
tonight enhances convergences across south central Kansas and
Oklahoma. So, while confidence that some precipitation will develop
and fall in the forecast area tonight, the advertised scattered
nature of the storms that will move in seem to warrant only a
chance POP for the overnight hours. Otherwise, storms may persist
through Sunday, shifting east into areas from northeast to central
and west central Missouri during the afternoon hours. While shear is
better in the post-frontal environment, instability will not be, so
no severe thunderstorm activity is expected.

Otherwise, looking at Monday, expect temperatures to range around to
just below normal for the day (which in later half of May means
beautiful conditions) as mostly sunny skies and north to northeast
winds make for a pleasant start to the work week.

Cutter


Medium Range (Tuesday through Saturday)...

This extended period of the forecast will be marked by dry
conditions and temperatures jumping to 10F+ degrees above normal.
Through the middle of this upcoming week, an area of surface high
pressure will shift just east of the area, dominating much of the
eastern and southeastern U.S. This surface pattern will result in a steady
southerly flow into the region, which will help support the rise in
temperatures. Tuesday into Wednesday, models show an area of low
pressure moving eastward into the Northern Plains and sagging
southward into the western part of the Central Plains. However,
thanks to an upper level ridge that will build in across much of the
eastern CONUS, this surface low will essentially be blocked from
entering into the forecast area due to this strong ridge. As a
result, any precipitation associated with this area of low pressure
looks to stay north and west of the region. Models show this
upper ridge remaining firmly in place through the end of the period.
One discrepancy amongst the models comes into play for the end of
the week with regards to whether or not the potential for
precipitation exists. GFS shows an upper level trough dropping
southward enough into the extreme Northern Plains that it may push
some of the precipitation from the surface low down into extreme
northeast Kansas and extreme northwest Missouri. Other models though
keep the trough in southern Canada which would limit the potential
for the precipitation to be pushed southward into the area. As a
result, have nothing more than slight chance pops Thursday night and
Friday across the extreme northwest corner of the forecast area.

As for temperatures, with the persistent southerly flow in place,
conditions on Tuesday will be a few degrees above normal and the
warming trend will continue through the period. Mild conditions are
expected for the latter half of the week and into next weekend as
temperatures steadily soar into the middle to upper 80s -- and
possibly into the lower 90s.

ACH

&&

.AVIATION...

For the 00Z TAFs...cold front over central KS has sparked off a
broken line of strong convection that is slowly progressing eastward.
This activity is expected to have a difficult time making it as far
east as the MO/KS border due to dry air in place per latest AMDAR
soundings out of MCI. Still, cannot rule out some weaker convection
developing later tonight as the cold front approaches and a weak LLJ
transports better moisture into the area. Will therefore keep the
VCTS wording for later this evening due to low chances of convection
near the western MO terminals. May see some MVFR cigs after the front
pushes through early Sunday morning, but upstream obs indicate more
VFR than MVFR so kept cigs more optimistic for now.

Hawblitzel

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KLSX 200005
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
705 PM CDT SAT MAY 19 2012

.UPDATE...
ISSUED AT 637 PM CDT SAT MAY 19 2012

NOT MUCH CHANGES IN THE GOING FORECASTS. UPDATED CLOUD COVER
MAINLY OVER EASTERN MISSOURI AND PARTS OF SOUTHWEST AND WEST
CENTRAL ILLINOIS AND REDUCED COVERAGE OVER CENTRAL MISSOURI.
OTHERWISE GOING FORECAST LOOKS GOOD.

PRZYBYLINSKI

&&

.SHORT TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(TONIGHT AND SUNDAY)

WITH A GOOD DIURNAL CUMULUS FIELD ACROSS MUCH OF THE AREA AND
UNSTABLE CONDITIONS COULD NOT RULE OUT AN ISOLATED SHOWER/STORM
ESPECIALLY ACROSS THE OZARKS LATE THIS AFTN/EARLY THIS EVNG...BUT
FOR NOW KEPT FORECAST DRY WITH LITTLE IF ANY FORCING OR SFC
BOUNDARIES TO INITIATE CONVECTION.  THE LOW LEVEL CLOUD FIELD SHOULD
DISSIPATE LATER THIS EVNG WITH LOSE OF DAYTIME HEATING.  MID-HIGH
LEVEL CLOUDINESS WILL INCREASE OVER THE AREA TGT WITH SW FLOW
SHORTWAVES APPROACHING OUR AREA AND INCREASING LOW-MID LEVEL WAA
AHEAD OF AN APPROACHING 850 MB TROUGH.  KEPT THE FORECAST DRY TGT AS
THE GFS MODEL WAS THE ONLY OPERATIONAL MODEL WHICH DEVELOPS ANY QPF
IN OUR AREA WELL AHEAD OF THE APPROACHING COLD FRONT NOW EXTENDING
FROM A WEAK SFC LOW OVER NRN MN SW THROUGH THE OK AND TX PNHDLS.
THIS COLD FRONT WILL DROP SEWD THROUGH MUCH OF OUR AREA ON SUN AS AN
UPPER LEVEL TROUGH MOVES EWD THROUGH THE NRN PLAINS.  AT LEAST
SCATTERED CONVECTION IS EXPECTED ALONG AND JUST AHEAD OF THIS FRONT
MAINLY ACROSS NERN AND CNTRL MO SUN MRNG AND ACROSS THE ENTIRE AREA
SUN AFTN. ALTHOUGH THERE WILL BE PLENTY OF LOW LEVEL MOISTURE AND
INSTABILITY SUN AFTN THE SFC CONVERGENCE ALONG THE FRONT LOOKS
RELATIVELY WEAK AND THE LOW-MID LEVEL SHEAR LOOKS WEAK AS WELL SO
ANY SEVERE OR NEAR SEVERE STORMS SHOULD BE SHORT LIVED AND
ISOLATED.  WITH INCREASED CLOUD COVER AND SCATTERED PRECIPITATION
HIGH TEMPERATURES SHOULD BE COOLER ON SUN MAINLY ACROSS NERN AND
CNTRL MO BEHIND THE COLD FRONT...BUT STILL WELL ABOVE NORMAL FROM ST
LOUIS S AND E AHEAD OF THE COLD FRONT.

GKS

&&

.LONG TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(SUNDAY NIGHT TO NEXT SATURDAY)

GFS/NAM SEEM TO BE IN REASONABLE AGREEMENT OVERALL IN MOVING THE
SHOWERS AND THUNDERSTORMS OUT OF THE AREA ON SUNDAY NIGHT.  WHILE
DETAILS ARE MESSY BECAUSE OF THE CONVECTIVE FEEDBACK...PARTICULARLY
IN THE GFS...SURFACE COLD FRONT THAT WILL EXTEND FROM CNTRL MO INTO
W CNTRL IL AT 00Z SUNDAY EVENING SHOULD MOVE SOUTHEAST AND CLEAR THE
CWA SHORTLY AFTER MIDNIGHT.  THEREAFTER IT STILL LOOKS LIKE DRY
WEATHER WILL PREVAIL THROUGH NEXT WEEKEND.  THE GLOBAL MODELS ARE IN
GOOD AGREEMENT THAT UPPER RIDGE WILL BUILD BACK INTO THE AREA AND
ANY FRONTS WILL REMAIN WELL NORTH OF THE CWA.

MOS TEMPERATURES ARE IN GOOD AGREEMENT THAT MONDAY AND TUESDAY`S
HIGHS WILL CLIMB TO AROUND NORMAL FOR MID MAY AS SURFACE WINDS
REMAIN OUT OF THE NORTH.  TEMPERATURES WILL THEN JUMP BACK WELL
ABOVE NORMAL MIDWEEK INTO SATURDAY AS DOMINANT SURFACE WIND FLOW
BECOMES SOUTHERLY WITH APPRECIABLE SUNSHINE. 850MB TEMPERATURES
WILL CLIMB UP TO AROUND 20C THURSDAY-SATURDAY WHICH SUPPORTS
SURFACE TEMPERATURES OF 90F OR GREATER.

BRITT

&&

.AVIATION...
ISSUED AT 657 PM CDT SAT MAY 19 2012

VFR AND DRY CONDITIONS EXPECTED TO CONTINUE OVERNIGHT. WINDS WILL
BACK THIS EVENING AND VEER TO SWLY SUN MORNING AHEAD OF AN
APPROACHING CDFNT. THIS FNT WILL BRING TSRA TO TERMINALS LATE
MORNING THRU MUCH OF THE AFTERNOON HRS. THE TIMING OF THE TSRA MAY
NEED TO BE ADJUSTED WITH FUTURE UPDATES...BUT APPEARS TO BE ON
TRACK ATTM. WINDS WILL BECOME WLY TO NWLY BEHIND THE FNT LATE SUN
AFTERNOON INTO THE EVENING.

TILLY

&&

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

$$

WFO LSX

000
FXUS63 KSGF 192349
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
649 PM CDT SAT MAY 19 2012

...UPDATE TO AVIATION...

.DISCUSSION...
//315 PM CDT SAT MAY 19 2012//
THE MAIN FORECAST CONCERN FOR THE NEXT 48 HOURS WILL BE
THUNDERSTORM CHANCES AS A COLD FRONT SLOWLY PUSHES THROUGH THE
REGION. TEMPERATURES WILL THEN TAKE CENTER STAGE STARTING AROUND
THE MIDDLE OF NEXT WEEK.

CURRENTLY...WATER VAPOR IMAGERY DEPICTS UPPER LEVEL SHORT WAVE
ENERGY TRACKING FROM NORTHEASTERN COLORADO INTO THE WESTERN CORN
BELT REGION. AT THE SURFACE...LOW PRESSURE WAS ANALYZED FAIRLY
CLOSE TO RUSSEL KANSAS. A DRY LINE TRAILED THE LOW DOWN INTO
NORTHWESTERN OKLAHOMA...WITH A COLD FRONT ON THE VERGE OF
OVERTAKING THE DRY LINE. OTHER THAN SOME MID LEVEL ECHOES OVER
WESTERN MISSOURI...THE REGIONAL RADAR COMPOSITE IS QUIET UNTIL YOU
GET BACK TO THE COOLING MID LEVELS DIRECTLY BENEATH THAT MID LEVEL
SHORT WAVE TROUGH.

THAT UPPER LEVEL WAVE WILL CONTINUE TO TRACK NORTHEAST TOWARDS THE
WESTERN GREAT LAKES FROM TONIGHT INTO SUNDAY MORNING. AS THE MAIN
MID LEVEL HEIGHT FALLS OVERSPREAD THE CENTRAL PLAINS LATER THIS
AFTERNOON AND THIS EVENING...THAT COLD FRONT WILL BEGIN TO DRIVE
EAST. THIS SHOULD BE PLENTY OF FORCING TO INITIATE CONVECTION FROM
CENTRAL KANSAS INTO NORTHWESTERN OKLAHOMA. AS WE HEAD INTO LATER
TONIGHT...THAT FRONT WILL BEGIN TO APPROACH SOUTHEASTERN KANSAS
AND WEST CENTRAL MISSOURI. WHILE THE MOST VIGOROUS CONVECTION WILL
OCCUR TO OUR WEST THIS EVENING...A FEW SHOWERS AND THUNDERSTORMS
SHOULD IMPACT AREAS GENERALLY ALONG AND WEST OF THE HIGHWAY 71
CORRIDOR LATE TONIGHT. NO SEVERE STORMS ARE EXPECTED GIVEN THE
LACK OF INSTABILITY AND SHEAR.

THAT FRONT WILL THEN CONTINUE TO PROGRESS EAST INTO THE OZARKS ON
SUNDAY. IT WILL BEGIN TO LOSE FORWARD MOMENTUM AS THE MAIN HEIGHT
FALLS PASS TO OUR NORTH. NEVERTHELESS...WEAK FORCING ALONG THE
FRONT WILL BE ENOUGH FOR SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. WHILE MODERATE AMOUNTS OF INSTABILITY WILL BE
PRESENT...SHEAR WILL BE WEAK. WILL CONTINUE WITH A SUB SEVERE WIND
AND HAIL THREAT IN THE HAZARDOUS WEATHER OUTLOOK...BUT THE
PROSPECT FOR SEVERE STORMS LOOKS VERY LOW.

THE NEXT FORECAST CONCERN THEN BECOMES WHEN THE THREAT FOR
THUNDERSTORMS WILL END...ESPECIALLY ACROSS SOUTHERN MISSOURI.
WHILE THE SURFACE FRONT WILL CLEAR THE STATE LINE...BOTH THE NAM
AND GFS HINT AT SLIGHTLY ELEVATED SLUGS OF CONVERGENCE INTO AT
LEAST MONDAY MORNING. LIFTING PARCELS IN THE 850 TO 750 LAYER DOES
INDEED YIELD LITTLE IN THE WAY OF INHIBITION. THUS...WILL HOLD ON
TO 20 TO 30 POPS ACROSS SOUTHERN MISSOURI INTO MONDAY MORNING.

WE ARE THEN LOOKING AT AN EXTENDED DRY PERIOD AS A PATTERN CHANGE
COMMENCES. A SLIGHTLY COOLER AIR MASS WILL INITIALLY FILTER INTO
THE REGION TO START NEXT WORK WEEK. OVERALL...NEAR NORMAL
TEMPERATURES ARE EXPECTED MONDAY AND TUESDAY.

LONG WAVE CHARTS THEN BEGIN TO AMPLIFY AND RETROGRADE A TROUGH
OVER WESTERN NORTH AMERICA LATER NEXT WEEK. WAVE FIVE CHARTS
CONTINUE TO INDICATE THAT THE TROUGH AXIS WILL EXTEND FROM THE
CANADIAN PRAIRIES...SOUTHWEST TOWARDS THE SOUTHERN CALIFORNIA
COAST. ONE CONCERNING TREND IS THAT THE LONG WAVE CHARTS HAVE
SHOWN A STRENGTHENING TREND WITH AN UPPER LEVEL HIGH CENTERED NEAR
THE CAROLINA COAST. THIS REGIME WOULD FAVOR A STRENGTHENING
SYNOPTIC SCALE UPPER LEVEL HIGH ACROSS THE MID MISSISSIPPI AND
OHIO VALLEY REGION. THE RESULT FOR OUR SENSIBLE WEATHER WOULD BE
DRY AND HOT CONDITIONS STARTING FROM LATER NEXT WEEK THROUGH AT
LEAST NEXT WEEKEND.

IN LIGHT OF THIS...HAVE BUMPED UP EXPECTED HIGHS INTO THE UPPER
80S AND LOWER 90S AREA WIDE. IF 85O MB TEMPERATURE PROGS FROM THE
ECMWF ARE CORRECT...MOST AREAS WILL BE IN THE 90S NEXT WEEKEND.
ONE PIECE OF GOOD NEWS IS THAT MANY AREAS OF THE OZARKS SHOULD SEE
GOOD MIXING. THUS...DEW POINTS AND RELATIVE HUMIDITIES SHOULD
REMAIN FAIRLY LOW. SLIGHTLY HIGHER DEW POINTS ARE EXPECTED FROM
THE HIGHWAY 71 CORRIDOR INTO THE TRUMAN LAKE REGION.

SCHAUMANN


&&

.AVIATION...
/ISSUED 633 PM CDT SAT MAY 19 2012/

FOR THE 20/0000Z KSGF/KJLN/KBBG TAFS...A COLD FRONT OVER THE
PLAINS WILL SHIFT EAST INTO SOUTHEAST KANSAS AND THE MISSOURI
OZARKS AFTER 12Z. SCATTERED THUNDERSTORMS ARE EXPECTED NEAR THE
FRONT AND HAVE INCLUDED TEMPO GROUPS FOR TSTMS IN ALL
TAFS...MOSTLY AFTER 16Z-18Z. TSTM EVOLUTION AND TIMING/COVERAGE ALONG
THE FRONT ARE IN SOME QUESTION AND WILL WATCH TRENDS TONIGHT INTO
SUNDAY. OUTSIDE OF THUNDERSTORMS EXPECT WINDS TO GRADUALLY
VEER AS THE FRONT APPROACHES WITH VFR CEILINGS AT TIMES.

DSA

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 192340
AFDLSX

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE ST LOUIS MO
640 PM CDT SAT MAY 19 2012

.UPDATE...
ISSUED AT 637 PM CDT SAT MAY 19 2012

NOT MUCH CHANGES IN THE GOING FORECASTS. UPDATED CLOUD COVER
MAINLY OVER EASTERN MISSOURI AND PARTS OF SOUTHWEST AND WEST
CENTRAL ILLINOIS AND REDUCED COVERAGE OVER CENTRAL MISSOURI.
OTHERWISE GOING FORECAST LOOKS GOOD.

PRZYBYLINSKI

&&

.SHORT TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(TONIGHT AND SUNDAY)

WITH A GOOD DIURNAL CUMULUS FIELD ACROSS MUCH OF THE AREA AND
UNSTABLE CONDITIONS COULD NOT RULE OUT AN ISOLATED SHOWER/STORM
ESPECIALLY ACROSS THE OZARKS LATE THIS AFTN/EARLY THIS EVNG...BUT
FOR NOW KEPT FORECAST DRY WITH LITTLE IF ANY FORCING OR SFC
BOUNDARIES TO INITIATE CONVECTION.  THE LOW LEVEL CLOUD FIELD SHOULD
DISSIPATE LATER THIS EVNG WITH LOSE OF DAYTIME HEATING.  MID-HIGH
LEVEL CLOUDINESS WILL INCREASE OVER THE AREA TGT WITH SW FLOW
SHORTWAVES APPROACHING OUR AREA AND INCREASING LOW-MID LEVEL WAA
AHEAD OF AN APPROACHING 850 MB TROUGH.  KEPT THE FORECAST DRY TGT AS
THE GFS MODEL WAS THE ONLY OPERATIONAL MODEL WHICH DEVELOPS ANY QPF
IN OUR AREA WELL AHEAD OF THE APPROACHING COLD FRONT NOW EXTENDING
FROM A WEAK SFC LOW OVER NRN MN SW THROUGH THE OK AND TX PNHDLS.
THIS COLD FRONT WILL DROP SEWD THROUGH MUCH OF OUR AREA ON SUN AS AN
UPPER LEVEL TROUGH MOVES EWD THROUGH THE NRN PLAINS.  AT LEAST
SCATTERED CONVECTION IS EXPECTED ALONG AND JUST AHEAD OF THIS FRONT
MAINLY ACROSS NERN AND CNTRL MO SUN MRNG AND ACROSS THE ENTIRE AREA
SUN AFTN. ALTHOUGH THERE WILL BE PLENTY OF LOW LEVEL MOISTURE AND
INSTABILITY SUN AFTN THE SFC CONVERGENCE ALONG THE FRONT LOOKS
RELATIVELY WEAK AND THE LOW-MID LEVEL SHEAR LOOKS WEAK AS WELL SO
ANY SEVERE OR NEAR SEVERE STORMS SHOULD BE SHORT LIVED AND
ISOLATED.  WITH INCREASED CLOUD COVER AND SCATTERED PRECIPITATION
HIGH TEMPERATURES SHOULD BE COOLER ON SUN MAINLY ACROSS NERN AND
CNTRL MO BEHIND THE COLD FRONT...BUT STILL WELL ABOVE NORMAL FROM ST
LOUIS S AND E AHEAD OF THE COLD FRONT.

GKS

&&

.LONG TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(SUNDAY NIGHT TO NEXT SATURDAY)

GFS/NAM SEEM TO BE IN REASONABLE AGREEMENT OVERALL IN MOVING THE
SHOWERS AND THUNDERSTORMS OUT OF THE AREA ON SUNDAY NIGHT.  WHILE
DETAILS ARE MESSY BECAUSE OF THE CONVECTIVE FEEDBACK...PARTICULARLY
IN THE GFS...SURFACE COLD FRONT THAT WILL EXTEND FROM CNTRL MO INTO
W CNTRL IL AT 00Z SUNDAY EVENING SHOULD MOVE SOUTHEAST AND CLEAR THE
CWA SHORTLY AFTER MIDNIGHT.  THEREAFTER IT STILL LOOKS LIKE DRY
WEATHER WILL PREVAIL THROUGH NEXT WEEKEND.  THE GLOBAL MODELS ARE IN
GOOD AGREEMENT THAT UPPER RIDGE WILL BUILD BACK INTO THE AREA AND
ANY FRONTS WILL REMAIN WELL NORTH OF THE CWA.

MOS TEMPERATURES ARE IN GOOD AGREEMENT THAT MONDAY AND TUESDAY`S
HIGHS WILL CLIMB TO AROUND NORMAL FOR MID MAY AS SURFACE WINDS
REMAIN OUT OF THE NORTH.  TEMPERATURES WILL THEN JUMP BACK WELL
ABOVE NORMAL MIDWEEK INTO SATURDAY AS DOMINANT SURFACE WIND FLOW
BECOMES SOUTHERLY WITH APPRECIABLE SUNSHINE. 850MB TEMPERATURES
WILL CLIMB UP TO AROUND 20C THURSDAY-SATURDAY WHICH SUPPORTS
SURFACE TEMPERATURES OF 90F OR GREATER.

BRITT

&&

.AVIATION...
ISSUED AT 1040 AM CDT SAT MAY 19 2012

CIRRUS CLOUDS WILL SPREAD NEWD INTO THE TAF SITES THIS AFTN...
PARTICULARLY UIN AND COU FROM DYING CONVECTION OVER WRN MO. SCT
DIURNAL CUMULUS CLOUDS WILL ALSO DEVELOP THIS AFTN. SLY SFC WINDS
WILL CONTINUE THIS AFTN AND TGT AHEAD OF AN APPROACHING COLD FRONT
NOW EXTENDING FROM A WEAK SFC LOW OVER NRN MN SW TO A WEAK SFC LOW
OVER THE OK PNHDL. MID-HI LEVEL CLOUDS WILL INCREASE LATE TGT INTO
SUN AHEAD OF THE APPROACHING UPPER LEVEL TROUGH OVER THE NRN
PLAINS AND ASSOCIATED COLD FRONT. SHOWERS AND STORMS WILL LIKELY
MOVE INTO UIN AND COU LATE SUN MRNG AND EVENTUALLY INTO THE STL
METRO AREA SUN AFTN ALONG AND JUST AHEAD OF THE COLD FRONT. WILL
INCLUDE EITHER PROB30 FOR TSRA OR VCTS IN THE TAFS ON SUN. THE SFC
WIND WILL VEER AROUND TO A SWLY DIRECTION SUN MRNG JUST AHEAD OF
THE COLD FRONT.

SPECIFICS FOR KSTL...SLY SFC WINDS WILL CONTINUE THIS AFTN
POSSIBLY GUSTY AT TIMES. JUST SCT CUMULUS CLOUDS AROUND 5000 FT
THIS AFTN ALONG WITH SOME CIRRUS CLOUDS. THE SFC WIND WILL
GRADUALLY VEER AROUND TO A SWLY DIRECTION SUN MRNG AND TO A WLY
DIRECTION BY THE END OF THE TAF FORECAST PERIOD AS THE COLD FRONT
MOVES THROUGH. WILL INCLUDE EITHER A PROB30 GROUP FOR TSRA OR VCTS
IN THE STL TAF SUN AFTN WITH AT LEAST SCATTERED TSRA EXPECTED
ALONG AND JUST AHEAD OF THE COLD FRONT AS IT MOVES SEWD THROUGH OUR
AREA.

GKS

&&

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

$$

WFO LSX

000
FXUS63 KEAX 192324
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
624 PM CDT Sat May 19 2012


...UPDATED AVIATION DISCUSSION...


.DISCUSSION...

Short Range (Today through Monday)...

This morning showers and thunderstorms developed on the edge of the
low level jet, where moisture convergence was maximized, though by
noon the storms had mostly dissipated as the jet mixed out with the
expanding boundary layer, leaving only isolated sprinkles and a
modest mid-level cloud deck moving east into Missouri. Farther
afield, a cold front is noted stretched from Minnesota south
southwest through eastern Nebraska, central Kansas, into the
panhandles of Oklahoma and Texas, and it will be this fronts
movement through Kansas and Missouri tonight into Sunday which will
be the focus for stormy activity. Otherwise, of note is a shortwave
currently exiting eastern Colorado, which will lift towards the
upper Great Lakes overnight and through Sunday. This movement will
help push the cold front wallowing to our west through eastern
Kansas and western Missouri late tonight through Sunday.

Tonight and Sunday...afternoon SPC analysis shows shows 1500-2000
J/KG of MLCAPE across east central Kansas and northwest Missouri
this afternoon, but it also shows MLCIN greater than -150 J/KG which
seems reasonable given the local ascent soundings from 1830Z at the
KMCI terminal, which shows a decent dry layer present between 850mb
and 600mb. Add to this the cloud cover across the region due to this
mornings fading storms, and convective initiation looks like it will
have to wait till late this afternoon to occur, likely in the
vicinity of the front which will still be in north central to
northeast Kansas. Moisture will be a somewhat limiting factor as
dewpoints have struggled to rise much beyond 60 degrees, with many
locations not even achieving that. Shear, especially in the cloud
baring layers away from the immediate vicinity of the front, is not
particularly high in the pre-frontal environment, so expectations
are that storms will have a very low potential for severe weather
outside of the far northwest corner of Missouri and adjacent areas
of extreme northeast Kansas, where large hail and strong winds would
be possible as the front arrives coincident with any thunderstorms.
Verity of models all share this outlook on the forecast, though they
also share an expectation that the main focus for activity will
shift to our north, as a jet streak rounds to shortwave and heads
northeast, and south, as what little low level jet is present late
tonight enhances convergences across south central Kansas and
Oklahoma. So, while confidence that some precipitation will develop
and fall in the forecast area tonight, the advertised scattered
nature of the storms that will move in seem to warrant only a
chance POP for the overnight hours. Otherwise, storms may persist
through Sunday, shifting east into areas from northeast to central
and west central Missouri during the afternoon hours. While shear is
better in the post-frontal environment, instability will not be, so
no severe thunderstorm activity is expected.

Otherwise, looking at Monday, expect temperatures to range around to
just below normal for the day (which in later half of May means
beautiful conditions) as mostly sunny skies and north to northeast
winds make for a pleasant start to the work week.

Cutter


Medium Range (Tuesday through Saturday)...

This extended period of the forecast will be marked by dry
conditions and temperatures jumping to 10F+ degrees above normal.
Through the middle of this upcoming week, an area of surface high
pressure will shift just east of the area, dominating much of the
eastern and southeastern U.S. This surface pattern will result in a steady
southerly flow into the region, which will help support the rise in
temperatures. Tuesday into Wednesday, models show an area of low
pressure moving eastward into the Northern Plains and sagging
southward into the western part of the Central Plains. However,
thanks to an upper level ridge that will build in across much of the
eastern CONUS, this surface low will essentially be blocked from
entering into the forecast area due to this strong ridge. As a
result, any precipitation associated with this area of low pressure
looks to stay north and west of the region. Models show this
upper ridge remaining firmly in place through the end of the period.
One discrepancy amongst the models comes into play for the end of
the week with regards to whether or not the potential for
precipitation exists. GFS shows an upper level trough dropping
southward enough into the extreme Northern Plains that it may push
some of the precipitation from the surface low down into extreme
northeast Kansas and extreme northwest Missouri. Other models though
keep the trough in southern Canada which would limit the potential
for the precipitation to be pushed southward into the area. As a
result, have nothing more than slight chance pops Thursday night and
Friday across the extreme northwest corner of the forecast area.

As for temperatures, with the persistent southerly flow in place,
conditions on Tuesday will be a few degrees above normal and the
warming trend will continue through the period. Mild conditions are
expected for the latter half of the week and into next weekend as
temperatures steadily soar into the middle to upper 80s -- and
possibly into the lower 90s.

ACH

&&

.AVIATION...

For the 00Z TAFs...cold front over central KS has sparked off a
broken line of strong convection that is slowly progressing eastward.
This activity is expected to have a difficult time making it as far
east as the MO/KS border due to dry air in place per latest AMDAR
soundings out of MCI. Still, cannot rule out some weaker convection
developing later tonight as the cold front approaches and a weak LLJ
transports better moisture into the area. Will therefore keep the
VCTS wording for later this evening due to low chances of convection
near the western MO terminals. May see some MVFR cigs after the front
pushes through early Sunday morning, but upstream obs indicate more
VFR than MVFR so kept cigs more optimistic for now.

Hawblitzel

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KEAX 192046
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
346 PM CDT Sat May 19 2012

.DISCUSSION...

Short Range (Today through Monday)...

This morning showers and thunderstorms developed on the edge of the
low level jet, where moisture convergence was maximized, though by
noon the storms had mostly dissipated as the jet mixed out with the
expanding boundary layer, leaving only isolated sprinkles and a
modest mid-level cloud deck moving east into Missouri. Farther
afield, a cold front is noted stretched from Minnesota south
southwest through eastern Nebraska, central Kansas, into the
panhandles of Oklahoma and Texas, and it will be this fronts
movement through Kansas and Missouri tonight into Sunday which will
be the focus for stormy activity. Otherwise, of note is a shortwave
currently exiting eastern Colorado, which will lift towards the
upper Great Lakes overnight and through Sunday. This movement will
help push the cold front wallowing to our west through eastern
Kansas and western Missouri late tonight through Sunday.

Tonight and Sunday...afternoon SPC analysis shows shows 1500-2000
J/KG of MLCAPE across east central Kansas and northwest Missouri
this afternoon, but it also shows MLCIN greater than -150 J/KG which
seems reasonable given the local ascent soundings from 1830Z at the
KMCI terminal, which shows a decent dry layer present between 850mb
and 600mb. Add to this the cloud cover across the region due to this
mornings fading storms, and convective initiation looks like it will
have to wait till late this afternoon to occur, likely in the
vicinity of the front which will still be in north central to
northeast Kansas. Moisture will be a somewhat limiting factor as
dewpoints have struggled to rise much beyond 60 degrees, with many
locations not even achieving that. Shear, especially in the cloud
baring layers away from the immediate vicinity of the front, is not
particularly high in the pre-frontal environment, so expectations
are that storms will have a very low potential for severe weather
outside of the far northwest corner of Missouri and adjacent areas
of extreme northeast Kansas, where large hail and strong winds would
be possible as the front arrives coincident with any thunderstorms.
Verity of models all share this outlook on the forecast, though they
also share an expectation that the main focus for activity will
shift to our north, as a jet streak rounds to shortwave and heads
northeast, and south, as what little low level jet is present late
tonight enhances convergences across south central Kansas and
Oklahoma. So, while confidence that some precipitation will develop
and fall in the forecast area tonight, the advertised scattered
nature of the storms that will move in seem to warrant only a
chance POP for the overnight hours. Otherwise, storms may persist
through Sunday, shifting east into areas from northeast to central
and west central Missouri during the afternoon hours. While shear is
better in the post-frontal environment, instability will not be, so
no severe thunderstorm activity is expected.

Otherwise, looking at Monday, expect temperatures to range around to
just below normal for the day (which in later half of May means
beautiful conditions) as mostly sunny skies and north to northeast
winds make for a pleasant start to the work week.

Cutter


Medium Range (Tuesday through Saturday)...

This extended period of the forecast will be marked by dry
conditions and temperatures jumping to 10F+ degrees above normal.
Through the middle of this upcoming week, an area of surface high
pressure will shift just east of the area, dominating much of the
eastern and southeastern U.S. This surface pattern will result in a steady
southerly flow into the region, which will help support the rise in
temperatures. Tuesday into Wednesday, models show an area of low
pressure moving eastward into the Northern Plains and sagging
southward into the western part of the Central Plains. However,
thanks to an upper level ridge that will build in across much of the
eastern CONUS, this surface low will essentially be blocked from
entering into the forecast area due to this strong ridge. As a
result, any precipitation associated with this area of low pressure
looks to stay north and west of the region. Models show this
upper ridge remaining firmly in place through the end of the period.
One discrepancy amongst the models comes into play for the end of
the week with regards to whether or not the potential for
precipitation exists. GFS shows an upper level trough dropping
southward enough into the extreme Northern Plains that it may push
some of the precipitation from the surface low down into extreme
northeast Kansas and extreme northwest Missouri. Other models though
keep the trough in southern Canada which would limit the potential
for the precipitation to be pushed southward into the area. As a
result, have nothing more than slight chance pops Thursday night and
Friday across the extreme northwest corner of the forecast area.

As for temperatures, with the persistent southerly flow in place,
conditions on Tuesday will be a few degrees above normal and the
warming trend will continue through the period. Mild conditions are
expected for the latter half of the week and into next weekend as
temperatures steadily soar into the middle to upper 80s -- and
possibly into the lower 90s.

ACH


&&

.AVIATION...

For the 18Z TAFs...Showers that where to the west of the terminals
earlier today have now dissipated leaving some thick mid-level clouds
across the region. Gusty south winds will continue through the
remainder of the daylight hours, before slacking off ahead of a cold
front that will move through early Sunday morning, switching winds
form the south southwest to the northwest. As for thunderstorms,
confidence is decent that storms will develop to the west of the
terminals after 03Z tonight, but as storms shift east through the
terminals confidence that there will be a solid line of storms is
low, as the expectation is this will be a broken to scattered line of
storms. Hence, have opted to go with VCTS at the terminals for the
late night hours. Later amendments are anticipated as the storms show
their hand late tonight. Otherwise, there could be some post frontal
storms Sunday morning, but confidence in their occurrence is low
enough to warrant not including in the TAFs at this time.

Cutter

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KSGF 192015
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
315 PM CDT SAT MAY 19 2012

.DISCUSSION...

THE MAIN FORECAST CONCERN FOR THE NEXT 48 HOURS WILL BE
THUNDERSTORM CHANCES AS A COLD FRONT SLOWLY PUSHES THROUGH THE
REGION. TEMPERATURES WILL THEN TAKE CENTER STAGE STARTING AROUND
THE MIDDLE OF NEXT WEEK.

CURRENTLY...WATER VAPOR IMAGERY DEPICTS UPPER LEVEL SHORT WAVE
ENERGY TRACKING FROM NORTHEASTERN COLORADO INTO THE WESTERN CORN
BELT REGION. AT THE SURFACE...LOW PRESSURE WAS ANALYZED FAIRLY
CLOSE TO RUSSEL KANSAS. A DRY LINE TRAILED THE LOW DOWN INTO
NORTHWESTERN OKLAHOMA...WITH A COLD FRONT ON THE VERGE OF
OVERTAKING THE DRY LINE. OTHER THAN SOME MID LEVEL ECHOES OVER
WESTERN MISSOURI...THE REGIONAL RADAR COMPOSITE IS QUIET UNTIL YOU
GET BACK TO THE COOLING MID LEVELS DIRECTLY BENEATH THAT MID LEVEL
SHORT WAVE TROUGH.

THAT UPPER LEVEL WAVE WILL CONTINUE TO TRACK NORTHEAST TOWARDS THE
WESTERN GREAT LAKES FROM TONIGHT INTO SUNDAY MORNING. AS THE MAIN
MID LEVEL HEIGHT FALLS OVERSPREAD THE CENTRAL PLAINS LATER THIS
AFTERNOON AND THIS EVENING...THAT COLD FRONT WILL BEGIN TO DRIVE
EAST. THIS SHOULD BE PLENTY OF FORCING TO INITIATE CONVECTION FROM
CENTRAL KANSAS INTO NORTHWESTERN OKLAHOMA. AS WE HEAD INTO LATER
TONIGHT...THAT FRONT WILL BEGIN TO APPROACH SOUTHEASTERN KANSAS
AND WEST CENTRAL MISSOURI. WHILE THE MOST VIGOROUS CONVECTION WILL
OCCUR TO OUR WEST THIS EVENING...A FEW SHOWERS AND THUNDERSTORMS
SHOULD IMPACT AREAS GENERALLY ALONG AND WEST OF THE HIGHWAY 71
CORRIDOR LATE TONIGHT. NO SEVERE STORMS ARE EXPECTED GIVEN THE
LACK OF INSTABILITY AND SHEAR.

THAT FRONT WILL THEN CONTINUE TO PROGRESS EAST INTO THE OZARKS ON
SUNDAY. IT WILL BEGIN TO LOSE FORWARD MOMENTUM AS THE MAIN HEIGHT
FALLS PASS TO OUR NORTH. NEVERTHELESS...WEAK FORCING ALONG THE
FRONT WILL BE ENOUGH FOR SCATTERED SHOWER AND THUNDERSTORM
DEVELOPMENT. WHILE MODERATE AMOUNTS OF INSTABILITY WILL BE
PRESENT...SHEAR WILL BE WEAK. WILL CONTINUE WITH A SUB SEVERE WIND
AND HAIL THREAT IN THE HAZARDOUS WEATHER OUTLOOK...BUT THE
PROSPECT FOR SEVERE STORMS LOOKS VERY LOW.

THE NEXT FORECAST CONCERN THEN BECOMES WHEN THE THREAT FOR
THUNDERSTORMS WILL END...ESPECIALLY ACROSS SOUTHERN MISSOURI.
WHILE THE SURFACE FRONT WILL CLEAR THE STATE LINE...BOTH THE NAM
AND GFS HINT AT SLIGHTLY ELEVATED SLUGS OF CONVERGENCE INTO AT
LEAST MONDAY MORNING. LIFTING PARCELS IN THE 850 TO 750 LAYER DOES
INDEED YIELD LITTLE IN THE WAY OF INHIBITION. THUS...WILL HOLD ON
TO 20 TO 30 POPS ACROSS SOUTHERN MISSOURI INTO MONDAY MORNING.

WE ARE THEN LOOKING AT AN EXTENDED DRY PERIOD AS A PATTERN CHANGE
COMMENCES. A SLIGHTLY COOLER AIRMASS WILL INITIALLY FILTER INTO
THE REGION TO START NEXT WORK WEEK. OVERALL...NEAR NORMAL
TEMPERATURES ARE EXPECTED MONDAY AND TUESDAY.

LONG WAVE CHARTS THEN BEGIN TO AMPLIFY AND RETROGRADE A TROUGH
OVER WESTERN NORTH AMERICA LATER NEXT WEEK. WAVE FIVE CHARTS
CONTINUE TO INDICATE THAT THE TROUGH AXIS WILL EXTEND FROM THE
CANADIAN PRAIRIES...SOUTHWEST TOWARDS THE SOUTHERN CALIFORNIA
COAST. ONE CONCERNING TREND IS THAT THE LONG WAVE CHARTS HAVE
SHOWN A STRENGTHENING TREND WITH AN UPPER LEVEL HIGH CENTERED NEAR
THE CAROLINA COAST. THIS REGIME WOULD FAVOR A STRENGTHENING
SYNOPTIC SCALE UPPER LEVEL HIGH ACROSS THE MID MISSISSIPPI AND
OHIO VALLEY REGION. THE RESULT FOR OUR SENSIBLE WEATHER WOULD BE
DRY AND HOT CONDITIONS STARTING FROM LATER NEXT WEEK THROUGH AT
LEAST NEXT WEEKEND.

IN LIGHT OF THIS...HAVE BUMPED UP EXPECTED HIGHS INTO THE UPPER
80S AND LOWER 90S AREA WIDE. IF 85O MB TEMPERATURE PROGS FROM THE
ECMWF ARE CORRECT...MOST AREAS WILL BE IN THE 90S NEXT WEEKEND.
ONE PIECE OF GOOD NEWS IS THAT MANY AREAS OF THE OZARKS SHOULD SEE
GOOD MIXING. THUS...DEW POINTS AND RELATIVE HUMIDITIES SHOULD
REMAIN FAIRLY LOW. SLIGHTLY HIGHER DEW POINTS ARE EXPECTED FROM
THE HIGHWAY 71 CORRIDOR INTO THE TRUMAN LAKE REGION.

SCHAUMANN

&&

.AVIATION...

FOR THE 18Z TAFS...

INITIAL AVIATION CONCERN THROUGH EARLY EVENING WILL BE GUSTY
SOUTHWEST WINDS...WITH GUSTS ABOVE 25 KTS EXPECTED. WINDS WILL
DISSIPATE WITH SUNSET THIS EVENING.

ATTENTION THEN TURNS TO A SLOW MOVING COLD FRONT CURRENTLY IN
CENTRAL KANSAS. AS THIS FRONT APPROACHES OVERNIGHT INTO THE
MORNING HOURS SUNDAY...SCATTERED THUNDERSTORMS WILL BE POSSIBLE.
THE BEST CHANCES THROUGH THE NEXT 24 HOURS WILL BE AT JLN AND
SGF AFTER SUNRISE SUNDAY...WHERE POTENTIAL HAS BEEN INDICATED WITH A
PROB30 GROUP.

BOXELL

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 191955
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
255 PM CDT SAT MAY 19 2012

.SHORT TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(TONIGHT AND SUNDAY)

WITH A GOOD DIURNAL CUMULUS FIELD ACROSS MUCH OF THE AREA AND
UNSTABLE CONDITIONS COULD NOT RULE OUT AN ISOLATED SHOWER/STORM
ESPECIALLY ACROSS THE OZARKS LATE THIS AFTN/EARLY THIS EVNG...BUT
FOR NOW KEPT FORECAST DRY WITH LITTLE IF ANY FORCING OR SFC
BOUNDARIES TO INITIATE CONVECTION.  THE LOW LEVEL CLOUD FIELD SHOULD
DISSIPATE LATER THIS EVNG WITH LOSE OF DAYTIME HEATING.  MID-HIGH
LEVEL CLOUDINESS WILL INCREASE OVER THE AREA TGT WITH SW FLOW
SHORTWAVES APPROACHING OUR AREA AND INCREASING LOW-MID LEVEL WAA
AHEAD OF AN APPROACHING 850 MB TROUGH.  KEPT THE FORECAST DRY TGT AS
THE GFS MODEL WAS THE ONLY OPERATIONAL MODEL WHICH DEVELOPS ANY QPF
IN OUR AREA WELL AHEAD OF THE APPROACHING COLD FRONT NOW EXTENDING
FROM A WEAK SFC LOW OVER NRN MN SW THROUGH THE OK AND TX PNHDLS.
THIS COLD FRONT WILL DROP SEWD THROUGH MUCH OF OUR AREA ON SUN AS AN
UPPER LEVEL TROUGH MOVES EWD THROUGH THE NRN PLAINS.  AT LEAST
SCATTERED CONVECTION IS EXPECTED ALONG AND JUST AHEAD OF THIS FRONT
MAINLY ACROSS NERN AND CNTRL MO SUN MRNG AND ACROSS THE ENTIRE AREA
SUN AFTN. ALTHOUGH THERE WILL BE PLENTY OF LOW LEVEL MOISTURE AND
INSTABILITY SUN AFTN THE SFC CONVERGENCE ALONG THE FRONT LOOKS
RELATIVELY WEAK AND THE LOW-MID LEVEL SHEAR LOOKS WEAK AS WELL SO
ANY SEVERE OR NEAR SEVERE STORMS SHOULD BE SHORT LIVED AND
ISOLATED.  WITH INCREASED CLOUD COVER AND SCATTERED PRECIPITATION
HIGH TEMPERATURES SHOULD BE COOLER ON SUN MAINLY ACROSS NERN AND
CNTRL MO BEHIND THE COLD FRONT...BUT STILL WELL ABOVE NORMAL FROM ST
LOUIS S AND E AHEAD OF THE COLD FRONT.

GKS

&&

.LONG TERM...
ISSUED AT 250 PM CDT SAT MAY 19 2012
(SUNDAY NIGHT TO NEXT SATURDAY)

GFS/NAM SEEM TO BE IN REASONABLE AGREEMENT OVERALL IN MOVING THE
SHOWERS AND THUNDERSTORMS OUT OF THE AREA ON SUNDAY NIGHT.  WHILE
DETAILS ARE MESSY BECAUSE OF THE CONVECTIVE FEEDBACK...PARTICULARLY
IN THE GFS...SURFACE COLD FRONT THAT WILL EXTEND FROM CNTRL MO INTO
W CNTRL IL AT 00Z SUNDAY EVENING SHOULD MOVE SOUTHEAST AND CLEAR THE
CWA SHORTLY AFTER MIDNIGHT.  THEREAFTER IT STILL LOOKS LIKE DRY
WEATHER WILL PREVAIL THROUGH NEXT WEEKEND.  THE GLOBAL MODELS ARE IN
GOOD AGREEMENT THAT UPPER RIDGE WILL BUILD BACK INTO THE AREA AND
ANY FRONTS WILL REMAIN WELL NORTH OF THE CWA.

MOS TEMPERATURES ARE IN GOOD AGREEMENT THAT MONDAY AND TUESDAY`S
HIGHS WILL CLIMB TO AROUND NORMAL FOR MID MAY AS SURFACE WINDS
REMAIN OUT OF THE NORTH.  TEMPERATURES WILL THEN JUMP BACK WELL
ABOVE NORMAL MIDWEEK INTO SATURDAY AS DOMINANT SURFACE WIND FLOW
BECOMES SOUTHERLY WITH APPRECIABLE SUNSHINE. 850MB TEMPERATURES
WILL CLIMB UP TO AROUND 20C THURSDAY-SATURDAY WHICH SUPPORTS
SURFACE TEMPERATURES OF 90F OR GREATER.

BRITT

&&

.AVIATION...
ISSUED AT 1040 AM CDT SAT MAY 19 2012

CIRRUS CLOUDS WILL SPREAD NEWD INTO THE TAF SITES THIS AFTN...
PARTICULARLY UIN AND COU FROM DYING CONVECTION OVER WRN MO. SCT
DIURNAL CUMULUS CLOUDS WILL ALSO DEVELOP THIS AFTN. SLY SFC WINDS
WILL CONTINUE THIS AFTN AND TGT AHEAD OF AN APPROACHING COLD FRONT
NOW EXTENDING FROM A WEAK SFC LOW OVER NRN MN SW TO A WEAK SFC LOW
OVER THE OK PNHDL. MID-HI LEVEL CLOUDS WILL INCREASE LATE TGT INTO
SUN AHEAD OF THE APPROACHING UPPER LEVEL TROUGH OVER THE NRN
PLAINS AND ASSOCIATED COLD FRONT. SHOWERS AND STORMS WILL LIKELY
MOVE INTO UIN AND COU LATE SUN MRNG AND EVENTUALLY INTO THE STL
METRO AREA SUN AFTN ALONG AND JUST AHEAD OF THE COLD FRONT. WILL
INCLUDE EITHER PROB30 FOR TSRA OR VCTS IN THE TAFS ON SUN. THE SFC
WIND WILL VEER AROUND TO A SWLY DIRECTION SUN MRNG JUST AHEAD OF
THE COLD FRONT.

SPECIFICS FOR KSTL...SLY SFC WINDS WILL CONTINUE THIS AFTN
POSSIBLY GUSTY AT TIMES. JUST SCT CUMULUS CLOUDS AROUND 5000 FT
THIS AFTN ALONG WITH SOME CIRRUS CLOUDS. THE SFC WIND WILL
GRADUALLY VEER AROUND TO A SWLY DIRECTION SUN MRNG AND TO A WLY
DIRECTION BY THE END OF THE TAF FORECAST PERIOD AS THE COLD FRONT
MOVES THROUGH. WILL INCLUDE EITHER A PROB30 GROUP FOR TSRA OR VCTS
IN THE STL TAF SUN AFTN WITH AT LEAST SCATTERED TSRA EXPECTED
ALONG AND JUST AHEAD OF THE COLD FRONT AS IT MOVES SEWD THROUGH OUR
AREA.

GKS

&&

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

$$

WFO LSX

000
FXUS63 KEAX 191747
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
1247 PM CDT Sat May 19 2012


...UPDATED AVIATION DISCUSSION...


.DISCUSSION...

Early this morning, mid-level clouds cover continues to stream
eastward towards the CWA as broad isentropic lift ahead of Great
Basin troughing intensifies. Cross sections and 00z RAOBs indicate a
general lack of moisture in the sub-600mb layer, with a narrow
corridor of moisture within the 312-320K surface. This corridor of
lift will continue into the mid-morning hours. While its feasible to
have a few very high based showers or perhaps a thunderstorm develop
in northeast Kansas or northwest Missouri the very dry sub-cloud
layer should limit much in the way of widespread measurable
precipitation.

Today: South to north oriented frontal boundary stretching across
western Kansas and into central Nebraska will slowly shift eastward
this morning as upper troughing begins to eject northeast. Models
suggest a narrow corridor of mid-level clouds lingering over eastern
Kansas and western Missouri into the afternoon hours which could put
a slight damper on afternoon temperatures. However, most areas will
still climb into the mid-upr 80s.

Other concern for today will be with winds. A sustained channel of
45-55 knot winds at 850 mb will persist into the afternoon hours over
eastern KS and western Missouri. Soundings suggest the ability to tap
into this layer with momentum transfer allowing for 20-25 knot
sustained winds with some higher gusts. The local area should remain
just shy of advisory criteria, but conditions will need to be
monitored.

Tonight: Limited boundary layer moisture will still allow for ample
instability (~2000 J/KG MLCAPE) to form along the stalled boundary
in central Kansas and Nebraska by mid-late afternoon. A fairly stout
EML will persist in these areas, but mid-level cooling should allow
for scattered thunderstorms to develop along and behind the boundary
later today. Depending on the final resting place of the surface
boundary, convection may be able to reach into northwestern Missouri
this evening. The primary threat of any strong storm would be large
hail and damaging winds. Shear profiles suggest multicellular
activity with storms clustering together as the evening progresses.
Further south, storms will struggle to move eastward into a more
stable environment over eastern KS and southwestern MO. Some
lingering showers will be possible as the front moves into the CWA.

Sunday: Surface high pressure will quickly race down the Plains on
Sunday, with the front reaching a Kirksville to Paola line by early
in the afternoon. Showers and thunderstorms will redevelop along the
boundary but quickly shift south of the CWA in the evening. With
limited instability and paltry shear, severe threats look to remain
low on Sunday.

Sunday night-Monday: Beautiful conditions will prevail heading into
the beginning of next week as high pressure remains in control.
Temperatures in the low to middle 70s can be expected on Monday.

Dux

Medium Range (Tuesday through Friday)...

As the old saying goes, "Big Bubble, No Trouble". However with the
increasing prospects for significant ridging over the middle/lower
Mississippi Valley region, we may be in big trouble as rainfall
deficits continue to build.

00Z solutions have come into better agreement today, trending toward
yesterday`s preferred 18/00Z ECWMF solution which favored a strong
closed low deepening along the Pacific coastline toward the end of
the medium range. Likewise, the development of an unseasonably
strong and elongated ridge from the middle/lower Mississippi Valley
region into the Northeast is also continued, resulting in
significant blocking across the CONUS. Both of these impressive
height anomalies create an unusual jet pattern for late May, with
strong flow from California across the Great Basin, then turning
quickly northeast through the central Rockies into the Upper
Midwest, and finally eastward across southern Canada.

Overall, this places the local region along the western flank of the
positive height anomaly beneath an area of significant warming aloft
and subsidence south of the primary jet branch. Despite some modest
improvement in low level moisture through the period on persistent
southerly winds, large scale precipitation chances look meager at
best -- favoring areas well to our north and west.

Some small upward adjustments to temperatures were made in the
latter periods and further trends may yield 90+ degree heat by the
end of next week. Overnight lows will also be at least 10 degrees
above normal.

Bookbinder

&&

.AVIATION...

For the 18Z TAFs...Showers that where to the west of the terminals
earlier today have now dissipated leaving some thick mid-level clouds
across the region. Gusty south winds will continue through the
remainder of the daylight hours, before slacking off ahead of a cold
front that will move through early Sunday morning, switching winds
form the south southwest to the northwest. As for thunderstorms,
confidence is decent that storms will develop to the west of the
terminals after 03Z tonight, but as storms shift east through the
terminals confidence that there will be a solid line of storms is
low, as the expectation is this will be a broken to scattered line of
storms. Hence, have opted to go with VCTS at the terminals for the
late night hours. Later amendments are anticipated as the storms show
their hand late tonight. Otherwise, there could be some post frontal
storms Sunday morning, but confidence in their occurrence is low
enough to warrant not including in the TAFs at this time.

Cutter

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KSGF 191700
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
1200 PM CDT SAT MAY 19 2012

...UPDATE TO AVIATION...

.DISCUSSION...

MILD CONDITIONS ARE CURRENTLY OCCURRING ACROSS THE REGION
AS EARLY MORNING TEMPERATURES ARE IN THE LOWER TO MIDDLE 60S. AN
UPPER LEVEL TROUGH IS CURRENTLY PUSHING EAST ACROSS THE ROCKIES
EARLY THIS MORNING. AHEAD OF THIS FEATURE A WEAK DISTURBANCE AND
AN AREA OF THETA-E ADVECTION IS TRACKING EAST ACROSS CENTRAL AND
EASTERN KANSAS. AT THIS POINT ONLY CLOUDS ARE ASSOCIATED WITH
THESE FEATURES. A FEW SHOWERS AND A FEW RUMBLES OF THUNDER MAY BE
ABLE TO DEVELOP ACROSS EASTERN KANSAS EARLY THIS MORNING. THE WEAK
UPPER LEVEL DISTURBANCE AND THETA-E ADVECTION WILL LIFT TO THE
NORTHEAST AND IF ANY PRECIPITATION CAN DEVELOP IT SHOULD GENERALLY
REMAIN WEST AND NORTH OF THE AREA THIS MORNING.

ANOTHER WARM DAY IS EXPECTED TODAY AS HIGHS ONCE AGAIN TOP OUT IN
THE MIDDLE TO UPPER 80S UNDER PARTLY CLOUDY SKIES. SURFACE LOW
PRESSURE THAT IS CURRENTLY ACROSS SOUTHWESTERN NEBRASKA AND
WESTERN KANSAS WILL RESULT IN A TIGHTER PRESSURE GRADIENT ACROSS THE
WESTERN PORTIONS OF THE FORECAST AREA. AS A RESULT SOUTHERLY WIND
GUSTS OVER 30 MPH WILL BE POSSIBLE AT TIMES THIS AFTERNOON
GENERALLY ALONG AND WEST OF THE HIGHWAY 65 CORRIDOR.

THE UPPER LEVEL TROUGH WILL CONTINUE TO TRACK EAST INTO THE
CENTRAL PLAINS BY THIS EVENING. THE TROUGH WILL THEN LIFT TO THE
NORTHEAST TONIGHT INTO SUNDAY NIGHT. A COLD FRONT WILL PUSH EAST
INTO THEN SAG SOUTHEAST THROUGH THE AREA LATE TONIGHT INTO SUNDAY
NIGHT GENERATING SHOWER AND THUNDERSTORM CHANCES ACROSS THE AREA.
WIND SHEAR WILL REMAIN WEAK ACROSS THE AREA AS THE BETTER DYNAMICS
REMAIN NORTH OF THE AREA. INSTABILITY SHOULD INCREASE ACROSS THE
AREA SUNDAY AFTERNOON AND EVENING AHEAD OF THE FRONT WITH THE
HEATING OF THE DAY. WITH THE WEAK WIND SHEAR ORGANIZED STORMS ARE
NOT EXPECTED...BUT IF ENOUGH INSTABILITY CAN DEVELOP A FEW
STRONGER UPDRAFTS CAPABLE OF HAIL AND GUSTY WINDS WILL BE
POSSIBLE. NO WIDESPREAD SEVERE WEATHER IS EXPECTED WITH THIS
ACTIVITY.

THE FRONT SHOULD PUSH SOUTH OF THE AREA BY MONDAY MORNING. COOLER
CONDITIONS WILL SPREAD INTO THE AREA TO START THE WORK WEEK WITH
HIGHS EXPECTED TO BE CLOSER TO NORMAL FOR THIS TIME OF YEAR WITH
HIGHS IN THE 70S. UPPER LEVEL RIDGING WILL THEN BUILD RIGHT BACK
OVER THE REGION WEDNESDAY INTO THE END OF NEXT WEEK RETURNING THE
ABOVE NORMAL TEMPERATURES TO THE AREA WITH HIGHS IN THE 80S
EXPECTED EACH AFTERNOON. THE RIDGE SHOULD KEEP THE AREA DRY AS THE
STORM TRACK SHOULD REMAIN WELL WEST AND NORTH OF THE AREA LATE
NEXT WEEK.

WISE


&&

.AVIATION...

FOR THE 18Z TAFS...

INITIAL AVIATION CONCERN THROUGH EARLY EVENING WILL BE GUSTY
SOUTHWEST WINDS...WITH GUSTS ABOVE 25 KTS EXPECTED. WINDS WILL
DISSIPATE WITH SUNSET THIS EVENING.

ATTENTION THEN TURNS TO A SLOW MOVING COLD FRONT CURRENTLY IN
CENTRAL KANSAS. AS THIS FRONT APPROACHES OVERNIGHT INTO THE
MORNING HOURS SUNDAY...SCATTERED THUNDERSTORMS WILL BE POSSIBLE.
THE BEST CHANCES THROUGH THE NEXT 24 HOURS WILL BE AT JLN AND
SGF AFTER SUNRISE SUNDAY...WHERE POTENTIAL HAS BEEN INDICATED WITH A
PROB30 GROUP.

BOXELL

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 191658
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
1158 AM CDT SAT MAY 19 2012

.SHORT TERM...
ISSUED AT 207 AM CDT SAT MAY 19 2012
(TODAY THROUGH SUNDAY)

APPEARS THAT THE STREAK OF DAYS WITHOUT MEASURABLE RAIN WILL END AT
12 AS MODEL GUIDANCE CONTINUES TO INDICATE A GOOD CHANCE OF SHOWERS
AND THUNDERSTORMS DEVELOPING AHEAD OF A COLD FRONT SUNDAY AFTERNOON
AND EVENING.

CURRENT UPPER AIR ANALYSIS SHOWS THE RIDGE AXIS SLOWLY MOVING EAST
OF THE AREA INTO THE OHIO RIVER VALLEY WITH A PROGRESSIVE TROF
ACROSS THE ROCKIES. THIS WILL ACT TO PLACE THE CWA UNDER SOUTHWEST
FLOW ALOFT TODAY...WITH 850MB TEMPERATURES SPIKING ABOVE
+16C...WHICH MIXES DOWN TO THE SURFACE AS UPPER 80S TO AROUND 90
DEGREES FAHRENHEIT.

SURFACE LOW PRESSURE CURRENTLY LOCATED ACROSS SOUTHEAST NEBRASKA
WILL BE MOVING NORTHEAST INTO THE UPPER MIDWEST TONIGHT AND
SUNDAY. TRAILING COLD FRONT IS FORECAST BY ALL MODEL GUIDANCE TO
STEADILY MARCH SOUTHEAST ACROSS THE CWA SUNDAY AND SUNDAY NIGHT.
MET/MAV GUIDANCE CONTINUE TO ADVERTISE CHANCE TO LOW END LIKELY
POPS FOR THIS TIME PERIOD. BELIEVE COVERAGE OF PRECIPITATION JUST
AHEAD OF THE FRONT MAY ULTIMATELY BECOME MORE THAN SCATTERED...BUT
GIVEN LACK OF SHEAR AND THEREFORE POTENTIAL FOR ORGANIZATION...AM
NOT COMFORTABLE INCREASING POPS HIGHER THAN 50 PERCENT AT THIS
TIME. THE WEAK DEEP LAYER SHEAR ALSO SHOULD KEEP ANY SEVERE
WEATHER REPORTS MARGINAL AND ISOLATED TO THE STRONGEST STORMS.

CVKING

&&

.LONG TERM...
ISSUED AT 207 AM CDT SAT MAY 19 2012
(MONDAY THROUGH FRIDAY)

HIGH PRESSURE STILL ON TRACK TO BUILD INTO THE MIDWEST ON MONDAY
WITH TEMPERATURES RETURNING BACK TO NORMAL. THIS WILL ONLY BE A
TEMPORARY COOL DOWN AS WE EXPECT A STEADY WARMING TREND HEADING
INTO AND THROUGH THE HOLIDAY WEEKEND AS A SUMMER-LIKE UPPER LEVEL
RIDGE BUILDS OVER THE MID MISSISSIPPI AND LOWER OHIO RIVER
VALLEYS. FORECAST REMAINS DRY WITH THE MAIN STORM TRACK RIDING
FROM THE PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES REGION.

CVKING

&&

.AVIATION...
ISSUED AT 1040 AM CDT SAT MAY 19 2012

CIRRUS CLOUDS WILL SPREAD NEWD INTO THE TAF SITES THIS AFTN...
PARTICULARLY UIN AND COU FROM DYING CONVECTION OVER WRN MO. SCT
DIURNAL CUMULUS CLOUDS WILL ALSO DEVELOP THIS AFTN. SLY SFC WINDS
WILL CONTINUE THIS AFTN AND TGT AHEAD OF AN APPROACHING COLD FRONT
NOW EXTENDING FROM A WEAK SFC LOW OVER NRN MN SW TO A WEAK SFC LOW
OVER THE OK PNHDL. MID-HI LEVEL CLOUDS WILL INCREASE LATE TGT INTO
SUN AHEAD OF THE APPROACHING UPPER LEVEL TROUGH OVER THE NRN
PLAINS AND ASSOCIATED COLD FRONT. SHOWERS AND STORMS WILL LIKELY
MOVE INTO UIN AND COU LATE SUN MRNG AND EVENTUALLY INTO THE STL
METRO AREA SUN AFTN ALONG AND JUST AHEAD OF THE COLD FRONT. WILL
INCLUDE EITHER PROB30 FOR TSRA OR VCTS IN THE TAFS ON SUN. THE SFC
WIND WILL VEER AROUND TO A SWLY DIRECTION SUN MRNG JUST AHEAD OF
THE COLD FRONT.

SPECIFICS FOR KSTL...SLY SFC WINDS WILL CONTINUE THIS AFTN
POSSIBLY GUSTY AT TIMES. JUST SCT CUMULUS CLOUDS AROUND 5000 FT
THIS AFTN ALONG WITH SOME CIRRUS CLOUDS. THE SFC WIND WILL
GRADUALLY VEER AROUND TO A SWLY DIRECTION SUN MRNG AND TO A WLY
DIRECTION BY THE END OF THE TAF FORECAST PERIOD AS THE COLD FRONT
MOVES THROUGH. WILL INCLUDE EITHER A PROB30 GROUP FOR TSRA OR VCTS
IN THE STL TAF SUN AFTN WITH AT LEAST SCATTERED TSRA EXPECTED
ALONG AND JUST AHEAD OF THE COLD FRONT AS IT MOVES SEWD THROUGH OUR
AREA.

GKS

&&

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

$$

WFO LSX

000
FXUS63 KLSX 191140
AFDLSX

AREA FORECAST DISCUSSION...UPDATED AVIATION
NATIONAL WEATHER SERVICE ST LOUIS MO
640 AM CDT SAT MAY 19 2012

.SHORT TERM...
ISSUED AT 207 AM CDT SAT MAY 19 2012
(TODAY THROUGH SUNDAY)

APPEARS THAT THE STREAK OF DAYS WITHOUT MEASURABLE RAIN WILL END AT
12 AS MODEL GUIDANCE CONTINUES TO INDICATE A GOOD CHANCE OF SHOWERS
AND THUNDERSTORMS DEVELOPING AHEAD OF A COLD FRONT SUNDAY AFTERNOON
AND EVENING.

CURRENT UPPER AIR ANALYSIS SHOWS THE RIDGE AXIS SLOWLY MOVING EAST
OF THE AREA INTO THE OHIO RIVER VALLEY WITH A PROGRESSIVE TROF
ACROSS THE ROCKIES. THIS WILL ACT TO PLACE THE CWA UNDER SOUTHWEST
FLOW ALOFT TODAY...WITH 850MB TEMPERATURES SPIKING ABOVE
+16C...WHICH MIXES DOWN TO THE SURFACE AS UPPER 80S TO AROUND 90
DEGREES FAHRENHEIT.

SURFACE LOW PRESSURE CURRENTLY LOCATED ACROSS SOUTHEAST NEBRASKA
WILL BE MOVING NORTHEAST INTO THE UPPER MIDWEST TONIGHT AND
SUNDAY. TRAILING COLD FRONT IS FORECAST BY ALL MODEL GUIDANCE TO
STEADILY MARCH SOUTHEAST ACROSS THE CWA SUNDAY AND SUNDAY NIGHT.
MET/MAV GUIDANCE CONTINUE TO ADVERTISE CHANCE TO LOW END LIKELY
POPS FOR THIS TIME PERIOD. BELIEVE COVERAGE OF PRECIPITATION JUST
AHEAD OF THE FRONT MAY ULTIMATELY BECOME MORE THAN SCATTERED...BUT
GIVEN LACK OF SHEAR AND THEREFORE POTENTIAL FOR ORGANIZATION...AM
NOT COMFORTABLE INCREASING POPS HIGHER THAN 50 PERCENT AT THIS
TIME. THE WEAK DEEP LAYER SHEAR ALSO SHOULD KEEP ANY SEVERE
WEATHER REPORTS MARGINAL AND ISOLATED TO THE STRONGEST STORMS.

CVKING

&&

.LONG TERM...
ISSUED AT 207 AM CDT SAT MAY 19 2012
(MONDAY THROUGH FRIDAY)

HIGH PRESSURE STILL ON TRACK TO BUILD INTO THE MIDWEST ON MONDAY
WITH TEMPERATURES RETURNING BACK TO NORMAL. THIS WILL ONLY BE A
TEMPORARY COOL DOWN AS WE EXPECT A STEADY WARMING TREND HEADING
INTO AND THROUGH THE HOLIDAY WEEKEND AS A SUMMER-LIKE UPPER LEVEL
RIDGE BUILDS OVER THE MID MISSISSIPPI AND LOWER OHIO RIVER
VALLEYS. FORECAST REMAINS DRY WITH THE MAIN STORM TRACK RIDING
FROM THE PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES REGION.

CVKING

&&

.AVIATION...
ISSUED AT 628 AM CDT SAT MAY 19 2012
VFR FLIGHT CONDITIONS AND SOUTHERLY FLOW WILL PREVAIL ACROSS THE
BI-STATE REGION TOADY. CURRENT THINKING IS THAT WIND WILL GUST TO
20-25 KTS THIS AFTERNOON ACROSS CENTRAL AND NORTHEAST MISSOURI.
REMAINDER OF THE AREA SHOULD HAVE LIGHTER WINDS...THO STILL
10-15KTS SUSTAINED. WINDS SHOULD DIMINISH AROUND SUNSET. RAIN
CHANCES WILL INCREASE TOWARD SUNDAY MORNING AS A COLD FRONT MOVES
INTO CENTRAL MISSOURI.

SPECIFICS FOR KSTL...
VFR FLIGHT CONDITIONS AND SOUTHERLY FLOW WILL PREVAIL AT LAMBERT TOADY.
THINK SUSTAINED WINDS WILL BE IN THE 10-15KTS RANGE...AND THERE
COULD BE SOME HIGHER GUSTS...THOUGH CONFIDENCE IS GREATER IN GUSTS
ACROSS CENTRAL MISSOURI. WINDS SHOULD DIMINISH AROUND SUNSET.
RAIN CHANCES WILL INCREASE LATE SUNDAY MORNING AND EARLY AFTERNOON AS
A COLD FRONT MOVES THROUGH CENTRAL MISSOURI.

CARNEY

&&

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

$$

WFO LSX

000
FXUS63 KEAX 191139
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
639 AM CDT SAT MAY 19 2012

...UPDATED AVIATION DISCUSSION...

.DISCUSSION...

Early this morning, mid-level clouds cover continues to stream
eastward towards the CWA as broad isentropic lift ahead of Great
Basin troughing intensifies. Cross sections and 00z RAOBs indicate a
general lack of moisture in the sub-600mb layer, with a narrow
corridor of moisture within the 312-320K surface. This corridor of
lift will continue into the mid-morning hours. While its feasible to
have a few very high based showers or perhaps a thunderstorm develop
in northeast Kansas or northwest Missouri the very dry sub-cloud
layer should limit much in the way of widespread measurable
precipitation.

Today: South to north oriented frontal boundary stretching across
western Kansas and into central Nebraska will slowly shift eastward
this morning as upper troughing begins to eject northeast. Models
suggest a narrow corridor of mid-level clouds lingering over eastern
Kansas and western Missouri into the afternoon hours which could put
a slight damper on afternoon temperatures. However, most areas will
still climb into the mid-upr 80s.

Other concern for today will be with winds. A sustained channel of
45-55 knot winds at 850 mb will persist into the afternoon hours over
eastern KS and western Missouri. Soundings suggest the ability to tap
into this layer with momentum transfer allowing for 20-25 knot
sustained winds with some higher gusts. The local area should remain
just shy of advisory criteria, but conditions will need to be
monitored.

Tonight: Limited boundary layer moisture will still allow for ample
instability (~2000 J/KG MLCAPE) to form along the stalled boundary
in central Kansas and Nebraska by mid-late afternoon. A fairly stout
EML will persist in these areas, but mid-level cooling should allow
for scattered thunderstorms to develop along and behind the boundary
later today. Depending on the final resting place of the surface
boundary, convection may be able to reach into northwestern Missouri
this evening. The primary threat of any strong storm would be large
hail and damaging winds. Shear profiles suggest multicellular
activity with storms clustering together as the evening progresses.
Further south, storms will struggle to move eastward into a more
stable environment over eastern KS and southwestern MO. Some
lingering showers will be possible as the front moves into the CWA.

Sunday: Surface high pressure will quickly race down the Plains on
Sunday, with the front reaching a Kirksville to Paola line by early
in the afternoon. Showers and thunderstorms will redevelop along the
boundary but quickly shift south of the CWA in the evening. With
limited instability and paltry shear, severe threats look to remain
low on Sunday.

Sunday night-Monday: Beautiful conditions will prevail heading into
the beginning of next week as high pressure remains in control.
Temperatures in the low to middle 70s can be expected on Monday.

Dux

Medium Range (Tuesday through Friday)...

As the old saying goes, "Big Bubble, No Trouble". However with the
increasing prospects for significant ridging over the middle/lower
Mississippi Valley region, we may be in big trouble as rainfall
deficits continue to build.

00Z solutions have come into better agreement today, trending toward
yesterday`s preferred 18/00Z ECWMF solution which favored a strong
closed low deepening along the Pacific coastline toward the end of
the medium range. Likewise, the development of an unseasonably
strong and elongated ridge from the middle/lower Mississippi Valley
region into the Northeast is also continued, resulting in
significant blocking across the CONUS. Both of these impressive
height anomalies create an unusual jet pattern for late May, with
strong flow from California across the Great Basin, then turning
quickly northeast through the central Rockies into the Upper
Midwest, and finally eastward across southern Canada.

Overall, this places the local region along the western flank of the
positive height anomaly beneath an area of significant warming aloft
and subsidence south of the primary jet branch. Despite some modest
improvement in low level moisture through the period on persistent
southerly winds, large scale precipitation chances look meager at
best -- favoring areas well to our north and west.

Some small upward adjustments to temperatures were made in the
latter periods and further trends may yield 90+ degree heat by the
end of next week. Overnight lows will also be at least 10 degrees
above normal.

Bookbinder


&&

.AVIATION...

Narrow axis of weak elevated instability was being realized by the
veering nocturnal jet across ern KS and ern NE early this morning.
Showers and a few thunderstorms will affect STJ and possibly MCI
between 1230 and 1400Z, with bases 12Kft, tops to 40Kft.

Once this activity exits, winds will strengthen quickly from the
south with speeds likely steady in the 15 to 20 knot range with
frequent gusts of 25 to 30 knots. Winds will lose their gusty
character around 00Z, with a gradual shift into the southwest this
evening and possibly west by the end of the TAF cycle as a weak
surface trough clears the terminals.

An additional corridor of modest instability, mainly focused across
the Plains, is expected to generate strong convection from ICT-SLN
later this afternoon. This activity may reach STJ later this
evening, but a rapid downward trend is expected owing to the
departing mid level trough and nocturnal stabilization. The VCTS at
STJ is carried from the previous TAFs, but timing/duration/intensity
remains unknown at this time.

Outside of thunderstorms, VFR conditions are expected through the
period.

Bookbinder

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KSGF 191100
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
600 AM CDT SAT MAY 19 2012

...UPDATE TO AVIATION...

.DISCUSSION...

MILD CONDITIONS ARE CURRENTLY OCCURRING ACROSS THE REGION
AS EARLY MORNING TEMPERATURES ARE IN THE LOWER TO MIDDLE 60S. AN
UPPER LEVEL TROUGH IS CURRENTLY PUSHING EAST ACROSS THE ROCKIES
EARLY THIS MORNING. AHEAD OF THIS FEATURE A WEAK DISTURBANCE AND
AN AREA OF THETA-E ADVECTION IS TRACKING EAST ACROSS CENTRAL AND
EASTERN KANSAS. AT THIS POINT ONLY CLOUDS ARE ASSOCIATED WITH
THESE FEATURES. A FEW SHOWERS AND A FEW RUMBLES OF THUNDER MAY BE
ABLE TO DEVELOP ACROSS EASTERN KANSAS EARLY THIS MORNING. THE WEAK
UPPER LEVEL DISTURBANCE AND THETA-E ADVECTION WILL LIFT TO THE
NORTHEAST AND IF ANY PRECIPITATION CAN DEVELOP IT SHOULD GENERALLY
REMAIN WEST AND NORTH OF THE AREA THIS MORNING.

ANOTHER WARM DAY IS EXPECTED TODAY AS HIGHS ONCE AGAIN TOP OUT IN
THE MIDDLE TO UPPER 80S UNDER PARTLY CLOUDY SKIES. SURFACE LOW
PRESSURE THAT IS CURRENTLY ACROSS SOUTHWESTERN NEBRASKA AND
WESTERN KANSAS WILL RESULT IN A TIGHTER PRESSURE GRADIENT ACROSS THE
WESTERN PORTIONS OF THE FORECAST AREA. AS A RESULT SOUTHERLY WIND
GUSTS OVER 30 MPH WILL BE POSSIBLE AT TIMES THIS AFTERNOON
GENERALLY ALONG AND WEST OF THE HIGHWAY 65 CORRIDOR.

THE UPPER LEVEL TROUGH WILL CONTINUE TO TRACK EAST INTO THE
CENTRAL PLAINS BY THIS EVENING. THE TROUGH WILL THEN LIFT TO THE
NORTHEAST TONIGHT INTO SUNDAY NIGHT. A COLD FRONT WILL PUSH EAST
INTO THEN SAG SOUTHEAST THROUGH THE AREA LATE TONIGHT INTO SUNDAY
NIGHT GENERATING SHOWER AND THUNDERSTORM CHANCES ACROSS THE AREA.
WIND SHEAR WILL REMAIN WEAK ACROSS THE AREA AS THE BETTER DYNAMICS
REMAIN NORTH OF THE AREA. INSTABILITY SHOULD INCREASE ACROSS THE
AREA SUNDAY AFTERNOON AND EVENING AHEAD OF THE FRONT WITH THE
HEATING OF THE DAY. WITH THE WEAK WIND SHEAR ORGANIZED STORMS ARE
NOT EXPECTED...BUT IF ENOUGH INSTABILITY CAN DEVELOP A FEW
STRONGER UPDRAFTS CAPABLE OF HAIL AND GUSTY WINDS WILL BE
POSSIBLE. NO WIDESPREAD SEVERE WEATHER IS EXPECTED WITH THIS
ACTIVITY.

THE FRONT SHOULD PUSH SOUTH OF THE AREA BY MONDAY MORNING. COOLER
CONDITIONS WILL SPREAD INTO THE AREA TO START THE WORK WEEK WITH
HIGHS EXPECTED TO BE CLOSER TO NORMAL FOR THIS TIME OF YEAR WITH
HIGHS IN THE 70S. UPPER LEVEL RIDGING WILL THEN BUILD RIGHT BACK
OVER THE REGION WEDNESDAY INTO THE END OF NEXT WEEK RETURNING THE
ABOVE NORMAL TEMPERATURES TO THE AREA WITH HIGHS IN THE 80S
EXPECTED EACH AFTERNOON. THE RIDGE SHOULD KEEP THE AREA DRY AS THE
STORM TRACK SHOULD REMAIN WELL WEST AND NORTH OF THE AREA LATE
NEXT WEEK.

WISE


&&

.AVIATION...

FOR THE 12Z TAFS...RADAR WAS SHOWING SOME LIGHT PRECIPITATION
ECHOES OVER EASTERN KANSAS JUST WEST OF THE CWA EARLY THIS MORNING
BUT FAIRLY DRY LOW LEVELS KEEPING THIS FROM REACHING THE GROUND OR
AS ONLY SPRINKLES. NOT EXPECTING ANYTHING MORE THAN SOME MID/HIGH
LEVEL CLOUD COVER TODAY. SURFACE WINDS WILL PICK UP BY MID MORNING
WITH GOOD MIXING AND A TIGHTENING SURFACE PRESSURE GRADIENT IN
ADVANCE OF THE NEXT AREA OF LOW PRESSURE IN THE PLAINS.

LINDENBERG

&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KEAX 190836
AFDEAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
336 AM CDT Sat May 19 2012

.DISCUSSION...

Early this morning, mid-level clouds cover continues to stream
eastward towards the CWA as broad isentropic lift ahead of Great
Basin troughing intensifies. Cross sections and 00z RAOBs indicate a
general lack of moisture in the sub-600mb layer, with a narrow
corridor of moisture within the 312-320K surface. This corridor of
lift will continue into the mid-morning hours. While its feasible to
have a few very high based showers or perhaps a thunderstorm develop
in northeast Kansas or northwest Missouri the very dry sub-cloud
layer should limit much in the way of widespread measurable
precipitation.

Today: South to north oriented frontal boundary stretching across
western Kansas and into central Nebraska will slowly shift eastward
this morning as upper troughing begins to eject northeast. Models
suggest a narrow corridor of mid-level clouds lingering over eastern
Kansas and western Missouri into the afternoon hours which could put
a slight damper on afternoon temperatures. However, most areas will
still climb into the mid-upr 80s.

Other concern for today will be with winds. A sustained channel of
45-55 knot winds at 850 mb will persist into the afternoon hours over
eastern KS and western Missouri. Soundings suggest the ability to tap
into this layer with momentum transfer allowing for 20-25 knot
sustained winds with some higher gusts. The local area should remain
just shy of advisory criteria, but conditions will need to be
monitored.

Tonight: Limited boundary layer moisture will still allow for ample
instability (~2000 J/KG MLCAPE) to form along the stalled boundary
in central Kansas and Nebraska by mid-late afternoon. A fairly stout
EML will persist in these areas, but mid-level cooling should allow
for scattered thunderstorms to develop along and behind the boundary
later today. Depending on the final resting place of the surface
boundary, convection may be able to reach into northwestern Missouri
this evening. The primary threat of any strong storm would be large
hail and damaging winds. Shear profiles suggest multicellular
activity with storms clustering together as the evening progresses.
Further south, storms will struggle to move eastward into a more
stable environment over eastern KS and southwestern MO. Some
lingering showers will be possible as the front moves into the CWA.

Sunday: Surface high pressure will quickly race down the Plains on
Sunday, with the front reaching a Kirksville to Paola line by early
in the afternoon. Showers and thunderstorms will redevelop along the
boundary but quickly shift south of the CWA in the evening. With
limited instability and paltry shear, severe threats look to remain
low on Sunday.

Sunday night-Monday: Beautiful conditions will prevail heading into
the beginning of next week as high pressure remains in control.
Temperatures in the low to middle 70s can be expected on Monday.

Dux

Medium Range (Tuesday through Friday)...

As the old saying goes, "Big Bubble, No Trouble". However with the
increasing prospects for significant ridging over the middle/lower
Mississippi Valley region, we may be in big trouble as rainfall
deficits continue to build.

00Z solutions have come into better agreement today, trending toward
yesterday`s preferred 18/00Z ECWMF solution which favored a strong
closed low deepening along the Pacific coastline toward the end of
the medium range. Likewise, the development of an unseasonably strong
and elongated ridge from the middle/lower Mississippi Valley region
into the Northeast is also continued, resulting in significant
blocking across the CONUS. Both of these impressive height anomalies
create an unusual jet pattern for late May, with strong flow from
California across the Great Basin, then turning quickly northeast
through the central Rockies into the Upper Midwest, and finally
eastward across southern Canada.

Overall, this places the local region along the western flank of the
positive height anomaly beneath an area of significant warming aloft
and subsidence south of the primary jet branch. Despite some modest
improvement in low level moisture through the period on persistent
southerly winds, large scale precipitation chances look meager at
best -- favoring areas well to our north and west.

Some small upward adjustments to temperatures were made in the latter
periods and further trends may yield 90+ degree heat by the end of
next week. Overnight lows will also be at least 10 degrees above
normal.

Bookbinder


&&

.AVIATION...

For the 06Z TAFs...VFR conditions will prevail through the next 24
hours, as what clouds develop will be rather high based due to
limited moisture. However, towards the end of this TAF cycle
(Saturday night) a threat for thunderstorm activity will begin to
push into northwest Missouri ahead of a cold front that will move
through the region Sunday. Confidence for inclusion in the terminal
forecast is only high enough to warrant VCTS in the KSTJ terminal at
this time. Have left them out of the Kansas City terminals as the
best timing for vicinity storms in these locations is currently just
beyond this TAF cycle. Otherwise, expect gusty south winds to prevail
through the day.

Cutter

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

WFO EAX

000
FXUS63 KSGF 190753
AFDSGF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SPRINGFIELD MO
253 AM CDT SAT MAY 19 2012

.DISCUSSION...

MILD CONDITIONS ARE CURRENTLY OCCURRING ACROSS THE REGION
AS EARLY MORNING TEMPERATURES ARE IN THE LOWER TO MIDDLE 60S. AN
UPPER LEVEL TROUGH IS CURRENTLY PUSHING EAST ACROSS THE ROCKIES
EARLY THIS MORNING. AHEAD OF THIS FEATURE A WEAK DISTURBANCE AND
AN AREA OF THETA-E ADVECTION IS TRACKING EAST ACROSS CENTRAL AND
EASTERN KANSAS. AT THIS POINT ONLY CLOUDS ARE ASSOCIATED WITH
THESE FEATURES. A FEW SHOWERS AND A FEW RUMBLES OF THUNDER MAY BE
ABLE TO DEVELOP ACROSS EASTERN KANSAS EARLY THIS MORNING. THE WEAK
UPPER LEVEL DISTURBANCE AND THETA-E ADVECTION WILL LIFT TO THE
NORTHEAST AND IF ANY PRECIPITATION CAN DEVELOP IT SHOULD GENERALLY
REMAIN WEST AND NORTH OF THE AREA THIS MORNING.

ANOTHER WARM DAY IS EXPECTED TODAY AS HIGHS ONCE AGAIN TOP OUT IN
THE MIDDLE TO UPPER 80S UNDER PARTLY CLOUDY SKIES. SURFACE LOW
PRESSURE THAT IS CURRENTLY ACROSS SOUTHWESTERN NEBRASKA AND
WESTERN KANSAS WILL RESULT IN A TIGHTER PRESSURE GRADIENT ACROSS THE
WESTERN PORTIONS OF THE FORECAST AREA. AS A RESULT SOUTHERLY WIND
GUSTS OVER 30 MPH WILL BE POSSIBLE AT TIMES THIS AFTERNOON
GENERALLY ALONG AND WEST OF THE HIGHWAY 65 CORRIDOR.

THE UPPER LEVEL TROUGH WILL CONTINUE TO TRACK EAST INTO THE
CENTRAL PLAINS BY THIS EVENING. THE TROUGH WILL THEN LIFT TO THE
NORTHEAST TONIGHT INTO SUNDAY NIGHT. A COLD FRONT WILL PUSH EAST
INTO THEN SAG SOUTHEAST THROUGH THE AREA LATE TONIGHT INTO SUNDAY
NIGHT GENERATING SHOWER AND THUNDERSTORM CHANCES ACROSS THE AREA.
WIND SHEAR WILL REMAIN WEAK ACROSS THE AREA AS THE BETTER DYNAMICS
REMAIN NORTH OF THE AREA. INSTABILITY SHOULD INCREASE ACROSS THE
AREA SUNDAY AFTERNOON AND EVENING AHEAD OF THE FRONT WITH THE
HEATING OF THE DAY. WITH THE WEAK WIND SHEAR ORGANIZED STORMS ARE
NOT EXPECTED...BUT IF ENOUGH INSTABILITY CAN DEVELOP A FEW
STRONGER UPDRAFTS CAPABLE OF HAIL AND GUSTY WINDS WILL BE
POSSIBLE. NO WIDESPREAD SEVERE WEATHER IS EXPECTED WITH THIS
ACTIVITY.

THE FRONT SHOULD PUSH SOUTH OF THE AREA BY MONDAY MORNING. COOLER
CONDITIONS WILL SPREAD INTO THE AREA TO START THE WORK WEEK WITH
HIGHS EXPECTED TO BE CLOSER TO NORMAL FOR THIS TIME OF YEAR WITH
HIGHS IN THE 70S. UPPER LEVEL RIDGING WILL THEN BUILD RIGHT BACK
OVER THE REGION WEDNESDAY INTO THE END OF NEXT WEEK RETURNING THE
ABOVE NORMAL TEMPERATURES TO THE AREA WITH HIGHS IN THE 80S
EXPECTED EACH AFTERNOON. THE RIDGE SHOULD KEEP THE AREA DRY AS THE
STORM TRACK SHOULD REMAIN WELL WEST AND NORTH OF THE AREA LATE
NEXT WEEK.

WISE

&&

.AVIATION...
/ISSUED 1105 PM CDT FRI MAY 18 2012/

FOR THE 19/0600Z KSGF/KJLN/KBBG TAFS...A COLD FRONT THAT EXTENDS
FROM THE DAKOTAS SOUTH INTO EASTERN CO WILL SHIFT SLOWLY
EAST...REACHING CNTRL KS BY LATE IN THE TAF PERIOD. LOW LEVEL WIND
FIELDS WILL STRENGTHEN OVER THE NEXT FEW HOURS AND KEPT LOW LEVEL
WIND SHEAR FOR ALL TAF SITES. GUSTY SOUTH WINDS CAN BE EXPECTED
AFTER 14Z WITH DAYTIME MIXING. VFR CONDITIONS ARE EXPECTED TO
CONTINUE.

DSA


&&

.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&

$$

000
FXUS63 KLSX 190712
AFDLSX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ST LOUIS MO
212 AM CDT SAT MAY 19 2012

.SHORT TERM...
ISSUED AT 207 AM CDT SAT MAY 19 2012
(TODAY THROUGH SUNDAY)

APPEARS THAT THE STREAK OF DAYS WITHOUT MEASURABLE RAIN WILL END AT
12 AS MODEL GUIDANCE CONTINUES TO INDICATE A GOOD CHANCE OF SHOWERS
AND THUNDERSTORMS DEVELOPING AHEAD OF A COLD FRONT SUNDAY AFTERNOON
AND EVENING.

CURRENT UPPER AIR ANALYSIS SHOWS THE RIDGE AXIS SLOWLY MOVING EAST
OF THE AREA INTO THE OHIO RIVER VALLEY WITH A PROGRESSIVE TROF
ACROSS THE ROCKIES. THIS WILL ACT TO PLACE THE CWA UNDER SOUTHWEST
FLOW ALOFT TODAY...WITH 850MB TEMPERATURES SPIKING ABOVE
+16C...WHICH MIXES DOWN TO THE SURFACE AS UPPER 80S TO AROUND 90
DEGREES FAHRENHEIT.

SURFACE LOW PRESSURE CURRENTLY LOCATED ACROSS SOUTHEAST NEBRASKA
WILL BE MOVING NORTHEAST INTO THE UPPER MIDWEST TONIGHT AND
SUNDAY. TRAILING COLD FRONT IS FORECAST BY ALL MODEL GUIDANCE TO
STEADILY MARCH SOUTHEAST ACROSS THE CWA SUNDAY AND SUNDAY NIGHT.
MET/MAV GUIDANCE CONTINUE TO ADVERTISE CHANCE TO LOW END LIKELY
POPS FOR THIS TIME PERIOD. BELIEVE COVERAGE OF PRECIPITATION JUST
AHEAD OF THE FRONT MAY ULTIMATELY BECOME MORE THAN SCATTERED...BUT
GIVEN LACK OF SHEAR AND THEREFORE POTENTIAL FOR ORGANIZATION...AM
NOT COMFORTABLE INCREASING POPS HIGHER THAN 50 PERCENT AT THIS
TIME. THE WEAK DEEP LAYER SHEAR ALSO SHOULD KEEP ANY SEVERE
WEATHER REPORTS MARGINAL AND ISOLATED TO THE STRONGEST STORMS.

CVKING

&&

.LONG TERM...
ISSUED AT 207 AM CDT SAT MAY 19 2012
(MONDAY THROUGH FRIDAY)

HIGH PRESSURE STILL ON TRACK TO BUILD INTO THE MIDWEST ON MONDAY
WITH TEMPERATURES RETURNING BACK TO NORMAL. THIS WILL ONLY BE A
TEMPORARY COOL DOWN AS WE EXPECT A STEADY WARMING TREND HEADING
INTO AND THROUGH THE HOLIDAY WEEKEND AS A SUMMER-LIKE UPPER LEVEL
RIDGE BUILDS OVER THE MID MISSISSIPPI AND LOWER OHIO RIVER
VALLEYS. FORECAST REMAINS DRY WITH THE MAIN STORM TRACK RIDING
FROM THE PLAINS INTO THE UPPER MIDWEST AND GREAT LAKES REGION.

CVKING

&&

.AVIATION...
ISSUED AT 1122 PM CDT FRI MAY 18 2012

NO MAJOR CHANGES AS DRY AND VFR CONDITIONS TO PREVAIL THROUGH THE
VALID TAF PERIOD. CONTINUE TO SEE SOUTHEAST WINDS EARLY THIS
MORNING...THEN PICKUP FROM THE SOUTH BY MIDDAY TODAY WITH SOME
HIGH CU...BEFORE DIMINISHING ONCE AGAIN TOWARDS SUNSET. MODELS
STILL SHOWING FRONTAL BOUNDARY APPROACHING REGION TONIGHT...BUT
RAIN TO HOLD OFF TIL AFTER TAF VALID PERIOD.

SPECIFICS FOR KSTL...NO MAJOR CHANGES AS DRY AND VFR CONDITIONS
TO PREVAIL THROUGH THE VALID TAF PERIOD. CONTINUE TO SEE
SOUTHEAST WINDS EARLY THIS MORNING...THEN PICKUP FROM THE SOUTH BY
18Z WITH SOME HIGH CU...BEFORE DIMINISHING ONCE BY 03Z AND BACK TO
THE SOUTHEAST. MODELS STILL SHOWING FRONTAL BOUNDARY APPROACHING REGION
TONIGHT...BUT RAIN TO HOLD OFF TIL AFTER 12Z SUNDAY.

BYRD

&&

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

$$

WFO LSX