000
FXUS63 KDDC 201154
AFDDDC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DODGE CITY KS
654 AM CDT MON MAY 20 2013

...UPDATED AVIATION SECTION...

.SYNOPSIS...
ISSUED AT 1135 PM CDT SUN MAY 19 2013

WV IMAGERY AND 00Z UPPER AIR ANALYSIS INDICATE A CLOSED OFF UPPER
LEVEL LOW OSCILLATING ACROSS SOUTH DAKOTA AND NORTHERN NEBRASKA.
MEANWHILE, AN UPPER LEVEL SHORTWAVE WITHIN THE BROADER SCALE TROUGH
IS DROPPING SOUTHEAST ACROSS THE GREAT BASIN REGION. A NARROW
+70KT UPPER LEVEL JET IS STREAMING EAST ACROSS NEW MEXICO INTO
THE TEXAS PANHANDLE. NEAR THE SURFACE, A STRONG AREA OF LOW
PRESSURE IS SITUATED ACROSS SOUTHERN NORTH DAKOTA WITH AN
ELONGATED TROUGH EXTENDING SOUTH THROUGH A SECONDARY LOW IN
EASTERN NEBRASKA, THEN FURTHER SOUTH INTO CENTRAL KANSAS. IR
SATELLITE DEPICTS A VERY SHARP DRYLINE EXTENDING FROM NEAR
WICHITA, KS IN SOUTH CENTRAL KANSAS TO JUST WEST OF ABILENE,
TEXAS. THE DRYLINE IS SLOWLY RETREATING WESTWARD.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 230 AM CDT MON MAY 20 2013

SHORT RANGE MODELS INDICATE THE CLOSED OFF UPPER LOW REMAINING
ANCHORED ACROSS THE NORTHERN PLAINS TODAY. MEANWHILE, THE UPPER
LEVEL SHORTWAVE ACROSS THE GREAT BASIN REGION WILL DROP SOUTHEAST
INTO THE DESERT SOUTHWEST BY THIS AFTERNOON. THE LARGER SCALE SYSTEM
WILL HELP SET OFF ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS FROM
THE UPPER MIDWEST SOUTHWESTWARD INTO THE SOUTH PLAINS OF OKLAHOMA
WHILE THE SMALLER SHORTWAVE BRINGS PRECIP CHANCES FROM THE FRONT
RANGE OF COLORADO AND NORTHERN NEW MEXICO INTO PORTIONS OF THE
WESTERN HIGH PLAINS. AS THE UPPER LEVEL SHORTWAVE APPROACHES, THE
+70KT UPPER LEVEL JET WILL SHIFT SLIGHTLY SOUTHWARD, YET STILL CLIMB
NORTHEAST ACROSS THE TEXAS PANHANDLE INTO SOUTH CENTRAL AND MUCH OF
SOUTHWEST KANSAS KEEPING MORE FAVORABLE DYNAMIC SUPPORT ALOFT IN
PLACE. NEAR THE SURFACE, THE NAM, GFS, AND UKMET SHOW A WEAK AREA
OF HIGH PRESSURE, ALREADY DEVELOPED ACROSS EASTERN COLORADO INTO
WESTERN KANSAS, SHIFTING SLIGHTLY SOUTHWARD TODAY. WITH THE SURFACE
LOW IN NORTHWEST TEXAS, THIS WILL CREATE A ZONE OF INCREASED LOW
LEVEL CONVERGENCE GENERALLY FROM THE TEXAS PANHANDLE WEST-NORTHWEST
INTO NORTHEAST NEW MEXICO AND SOUTHEAST COLORADO. COMBINED WITH
THE JET DYNAMICS ALOFT, A FEW THUNDERSTORMS WILL BE POSSIBLE LATE
THIS MORNING AND AFTERNOON ACROSS THE WESTERN HIGH PLAINS OF
SOUTHERN COLORADO, NORTHEAST NEW MEXICO, AND POSSIBLY EXTREME
SOUTHWEST KANSAS.

IN THE MEANTIME, AS COOL AIR ADVECTION IN THE MID LEVELS CONTINUES
TO ENFORCE STEEPER LAPSE RATES ACROSS THE WESTERN HIGH PLAINS, ALL
SHORT RANGE MODELS POINT TO H7 FRONTOGENETIC FORCING DEVELOPING
ACROSS SOUTHWEST KANSAS EARLY TO MID DAY. ALTHOUGH INSTABILITY
WILL BE MODEST AT BEST WITH CAPE VALUES UP NEAR 500 J/KG, A FEW
ISOLATED THUNDERSTORMS CANNOT BE RULED OUT ACROSS THE REMAINDER OF
SOUTHWEST AND CENTRAL KANSAS. HOWEVER, SEVERE WEATHER IS UNLIKELY
WITH POOR SHEAR PROFILES AND THE LOWER INSTABILITY. WILL RETAIN A
MENTION OF SLIGHT POPS FOR TODAY.

TEMPERATURES WILL BE RATHER PLEASANT TODAY AS SURFACE HIGH PRESSURE
ACROSS THE WESTERN HIGH PLAINS HELPS DRAW SLIGHTLY COOLER AIR SOUTH
INTO WESTERN KANSAS WITHIN A NORTH TO NORTHWESTERLY LOW LEVEL FLOW.
THE NAM, GFS, AND UKMET SHOW H85 TEMPERATURES DOWN A BIT FROM
YESTERDAY WITH AROUND TO A LITTLE ABOVE 15C ACROSS MUCH OF SOUTHWEST
AND CENTRAL KANSAS. LOOK FOR HIGHS GENERALLY UP INTO THE 70S(F) THIS
AFTERNOON WITH NEAR 80F POSSIBLE IN SOUTH CENTRAL KANSAS. WITH THE
SLIGHTLY COOLER AIR MASS IN PLACE, EXPECT LOWS DOWN INTO THE 40S(F)
MONDAY NIGHT WITH THE LOWER 50S(F) STILL POSSIBLE IN SOUTH CENTRAL
KANSAS.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 403 AM CDT MON MAY 20 2013

THE DEEP UPPER LEVEL CYCLONE SPINNING OVER THE NORTHERN PLAINS WILL
MOVE LITTLE THROUGH TUESDAY, AND WESTERN KANSAS WILL BE INFLUENCED
BY COLD CYCLONIC UPPER LEVEL FLOW. AN UPPER LEVEL TROUGH EVIDENT ON
SATELLITE IMAGERY NEAR THE NORTHERN NEVADA BORDER WILL RIPPLE
THROUGH THE FLOW AND APPROACH THE TEXAS PANHANDLE TUESDAY MORNING. A
MINOR WAVE ROTATING AROUND THE NORTHERN PLAINS GYRE WILL MOVE ACROSS
NORTHERN KANSAS DURING THE DAY TUESDAY. UPSTREAM IN THE PACIFIC,
STRONG WARM AIR ADVECTION AROUND A DEEP CYCLONE NEAR THE DATELINE
WILL CONTINUE TO BUILD HEIGHTS NEAR 150W, AND THE UPPER LEVEL
CYCLONE NORTH OF BRITISH COLUMBIA WILL DROP SOUTHEAST INTO OREGON BY
WEDNESDAY MORNING. AMPLIFICATION OF THE LONG WAVE TROUGH IN EASTERN
CANADA FINALLY WILL EJECT THE NORTHERN PLAINS CYCLONE, AND RIDGING
WILL BUILD IN THE CENTRAL PART OF THE COUNTRY. COOL AIR WILL DROP
INTO THE UPPER MIDWEST AS THE CANADIAN UPPER LEVEL TROUGH AMPLIFIES,
AND A STRONG BAROCLINIC ZONE WILL DEVELOP IN THE CENTRAL PLAINS BY
MID WEEK. FALLING PRESSURES IN THE NORTHERN ROCKIES WEDNESDAY AND
THURSDAY WILL RESULT IN DEEP SOUTHEAST FLOW AND MOISTURE RETURN TO
THE HIGH PLAINS. THE OLD FRONTAL BOUNDARY IN THE SOUTHERN PLAINS
WILL BEGIN TO MOVE NORTH AS A WARM FRONT THURSDAY AND SHOULD REACH
NORTHERN KANSAS BY SATURDAY MORNING. THUNDERSTORMS ARE LIKELY TO
DEVELOP THURSDAY NEAR THE WARM FRONT IN NORTHERN OKLAHOMA WITH
ANOTHER CLUSTER FORMING IN THE MOIST UPSLOPE FLOW IN EASTERN
COLORADO. THE COLORADO CLUSTER SHOULD RIPPLE DOWN THE BAROCLINIC
ZONE DURING THE NIGHT AND MAY PRODUCE WIDESPREAD BENEFICIAL RAINFALL
IN SOUTHWEST KANSAS. ANOTHER CLUSTER PROBABLY WILL FORM A LITTLE
FARTHER NORTH FRIDAY NIGHT. BY SATURDAY THE WARM SHOULD BE NEAR THE
NEBRASKA BORDER, AND VERY WARM MID LEVEL TEMPERATURES IN KANSAS WILL
SHIFT THE FAVORED AREA FOR MESOSCALE CONVECTIVE SYSTEMS FARTHER
NORTH.

TROPICAL THUNDERSTORMS HAVE BECOME LESS PROMINENT IN THE INDIAN
OCEAN IN RECENT DAYS, BUT THE ENHANCED THUNDERSTORMS MAY HAVE
CONTRIBUTED TO THE STRONG HIGH LEVEL JET EXTENDING FROM ASIA ACROSS
JAPAN INTO THE WESTERN PACIFIC TODAY. THIS STRONG JET WILL PROPAGATE
ACROSS THE PACIFIC AND APPROACH THE WESTERN UNITED STATES BY EARLY
NEXT WEEK AND WILL SUPPORT MAINTENANCE OF A LONG WAVE TROUGH IN THE
WESTERN PART OF THE COUNTRY. AS THE JET PROPAGATES THROUGH THE LONG
WAVE AND APPROACHES THE CENTRAL UNITED STATES TOWARD THE END OF MAY,
ANOTHER PERIOD OF VERY ACTIVE SEVERE WEATHER MAY EVOLVE. SYNOPTIC
SCALE DETAILS ARE IMPOSSIBLE TO FORECAST THAT FAR IN THE FUTURE.

TUESDAY WILL BE ANOTHER MILD DAY WITH HIGHS IN THE 70S. SOME HIGH
BASED VIRGA SHOWERS ARE POSSIBLE WITH THE APPROACH OF THE UPPER
LEVEL TROUGH ROTATING AROUND THE NORTHERN PLAINS GYRE, BUT MODEL
SOUNDINGS SUGGEST THAT MID LEVEL INSTABILITY WILL BE MARGINAL TO
NONEXISTENT. AS SUCH, THE CHANCE FOR MEASURABLE RAINFALL IS MINIMAL,
AND THE LOW POPS NEAR INTERSTATE 70 WERE REMOVED. WEDNESDAY SHOULD
BE QUIET IN WESTERN KANSAS WITH UPPER LEVEL RIDGING AND MINIMAL LOW
LEVEL MOISTURE. BY LATE WEDNESDAY, THERE MAY BE ENOUGH MOISTURE
RETURN IN SOUTHEAST COLORADO TO SUPPORT A FEW THUNDERSTORMS THAT
COULD CLIP SOUTHWEST KANSAS DURING THE EVENING.

ABUNDANT LOW LEVEL MOISTURE WILL RETURN THURSDAY WITH H8 DEWPOINTS
ABOVE 10 C ACROSS MUCH OF SOUTHWEST KANSAS. THE SURFACE WARM FRONT
SHOULD EXTEND FROM SOUTHEAST COLORADO INTO CENTRAL OKLAHOMA THURSDAY
AFTERNOON. THERE MAY BE QUITE A BIT OF STRATUS NORTH OF THE WARM
FRONT THURSDAY, AND TEMPERATURES MAY BE COOLER THAN CURRENTLY
DEPICTED IN THE FORECAST GRIDS. A CLUSTER OF THUNDERSTORMS SHOULD
MOVE ACROSS SOUTHWEST KANSAS THURSDAY NIGHT. PROGRESSION OF THE WARM
FRONT FRIDAY WILL BE AFFECTED BY OUTFLOW FROM THURSDAY NIGHT
CONVECTION, AND POSITION OF THE FRONT WILL DETERMINE WHERE
THUNDERSTORMS FORM AGAIN FRIDAY AFTERNOON AND FRIDAY NIGHT. BY
SATURDAY, THE NUMERICAL MODELS ARE IN GOOD AGREEMENT THAT THE FRONT
WILL PROGRESS TO NEAR THE NEBRASKA BORDER, AND MORE SUMMERLIKE
TEMPERATURES WILL RETURN TO WESTERN KANSAS.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 642 AM CDT MON MAY 20 2013

VFR CONDITIONS WILL PREVAIL THROUGH TUESDAY WITH SCATTERED TO BROKEN
CLOUDINESS AOA 080. AN UPPER LEVEL LOW CENTERED OVER SOUTH DAKOTA
WILL REMAIN NEARLY STATIONARY TODAY AND TUESDAY. AN UPPER LEVEL
TROUGH IN NORTHERN NEW MEXICO WILL MOVE INTO CENTRAL KANSAS THIS
AFTERNOON. SUFFICIENT MID LEVEL INSTABILITY EXISTS TO SUPPORT
DEVELOPMENT OF SCATTERED SHOWERS AND A FEW THUNDERSTORMS WITH BASES
AROUND 080 AFTER 19Z. LIGHTNING AND WIND GUSTS TO 40KT MAY OCCUR
WITH THE THUNDERSTORMS. THE SHOWERS AND THUNDERSTORMS WILL DISSIPATE
AROUND SUNSET. AT THE SURFACE, WEAK HIGH PRESSURE WILL BUILD INTO
WESTERN KANSAS. LOW LEVEL WINDS WILL BE NORTHWEST AT 10 TO 15
KTS.

&&

.PRELIMINARY POINT TEMPS/POPS...
DDC  77  48  77  49 /  20  20  10  10
GCK  76  47  75  47 /  20  20  10  10
EHA  75  47  77  48 /  20  20  10  10
LBL  77  47  78  49 /  20  20  10  10
HYS  77  47  73  48 /  20  20  10  10
P28  80  52  79  52 /  20  20  10  10

&&

.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SYNOPSIS...JJOHNSON
SHORT TERM...JJOHNSON
LONG TERM...RUTHI
AVIATION...RUTHI