Special Weather Statement, NWS Goodland, KS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GOODLAND KS
1110 AM MDT TUE AUG 9 2011

.UPDATE...
449 AM MDT TUE AUG 9 2011

LIGHT DRAINAGE WIND HAS DEVELOPED ACROSS MUCH OF THE AREA WITH
LIGHT WESTERLY WINDS OBSERVED AT MOST LOCATIONS. WHILE WINDS ARE
NOT STRONG ENOUGH TO ADD MUCH OF AN OROGRAPHIC IMPACT...TDS HAVE
BEEN FALLING WITH TEMPS WHICH SUGGEST MOIST LAYER SHALLOWER THAN
PREVIOUSLY EXPECTED. MAY BE A FEW PATCHED OF FOG OUT THERE...BUT
WILL LIMIT COVERAGE AND IMPACT ON SKY COVER BASED ON CURRENT TRENDS.

AFTER TAKING A CLOSER LOOK AT SEVERE WEATHER POTENTIAL
TODAY...HAVE DECIDED TO MENTION A THREAT OF SEVERE WEATHER IN
CURRENT FORECAST. GIVEN THE SIGNIFICANT STORMS THAT FORMED
YESTERDAY WITH WEAKER SHEAR AND SIMILAR INSTABILIY
PROFILES...THINK THREAT WARRANTS MENTION IN CURRENT FORECAST.

JRM
&&

.DISCUSSION...
251 AM MDT TUE AUG 9 2011

0330Z WATER VAPOR IMAGERY INDICATED MORE AMPLIFIED FLOW ALOFT THAN
THE PAST FEW DAYS WITH SHORT WAVE RIDGE OVER THE ROCKIES AND SHORT
WAVE TROUGH MOVING ACROSS MINNESOTA. AT THE SFC...1012 RIDGE AXIS
WAS NOSING INTO AREA AT 4Z WITH FRONTAL ZONE WELL TO THE SOUTH OF
THE AREA. OBSERVED SOUNDINGS FROM AROUND THE AREA INDICATED VERY DRY
AIRMASS REMAINED IN PLACE ACROSS CENTRAL AND WESTERN COLORADO...BUT
GIVEN EXPECTED SFC FLOW THIS AIR MASS WILL LIKELY NOT HAVE A LARGE
IMPACT.

MAIN FORECAST CONCERNS WILL CENTER AROUND PRECIP CHANCES/AMOUNTS
TONIGHT AND WEDNESDAY MORNING.

TODAY-TONIGHT...INITIAL CONCERNS WILL BE FOG AND EARLY MORNING
PRECIPITATION CHANCES. WITH SFC HIGH OVER THE AREA AND PLENTY OF
CLEAR SKIES...STILL LOOKS LIKE THERE WILL BE A DECENT THREAT FOR
SOME FOG DEVELOPMENT OVERNIGHT...BUT NOT SEEING A LARGE INCREASE IN
TDS UPSTREAM...SO WHEN LIGHT SOUTHEASTERLY FLOW DEVELOPS NOT SURE
THERE WILL BE A BIG ADVECTIVE COMPONENT...BUT WILL SEE HOW THINGS
DEVELOP BEFORE MAKING A FINAL CALL. HAVE SOME CONCERNS THAT AN
ISOLATED STORM WILL DEVELOP AROUND 12Z ACROSS NORTHERN ZONES IN AREA
OF STRONG WAA ALONG PERIPHERY OF H7 THERMAL RIDGE.  POINT SOUNDINGS
BRING SOME CONCERNS IF ANY PARCELS WILL SATURATE AND REALIZE THE
POTENTIALLY STRONG INSTABILITY...SO DO NOT THINK COVERAGE WILL BE
MORE THAN ISOLATED AT THIS TIME. OTHERWISE...THINK POTENTIAL FOR
WIDESPREAD PRECIPITATION WILL STEADILY INCREASE THROUGH THE
AFTERNOON AND EVENING HOURS...WITH BEST CHANCES LIKELY AFTER
MIDNIGHT WHEN PV ADVECTION/DIV Q FIELDS INDICATE STRONGEST LARGE
SCALE FORCING FOR ASCENT IS PRESENT. MOISTURE TRANSPORT VECTORS
INCREASE SHARPLY OVERNIGHT...ESPECIALLY ON 315K SFC AND WITH
EXPECTED WIDESPREAD ISENTROPIC ASCENT...APPROACHING PV ANOMALY AND
GENERAL MODEL CONSENSUS THINK INCREASING POPS IS WARRANTED. HAVE
SOME CONCERNS LOOKING AT LATEST SREF DATA THAT THINGS MAY BE MORE
CONFINED TO THE EXTREME EASTERN PORTION OF THE AREA...BUT THINK
INCREASING POPS INTO THE LIKELY CATEGORY STILL WARRANTED BASED ON
LATEST DATA. VERY MOIST AIR WITH MIXING RATIOS IN THE 10-13 G/KG
RANGE IN AREA OF ASCENT AND A DEEP WARM LAYER WILL CERTAINLY PROMOTE
A HEAVY RAIN THREAT EVEN THOUGH STORM MOTIONS WILL BE FASTER THAN
PREVIOUS DAYS.

WEDNESDAY-WEDNESDAY NIGHT...MAIN CONCERN FOR THE PERIOD WILL BE IF
PRECIPITATION WILL BE ONGOING OR NOT PRECIPITATION WILL BE ONGOING
AND WHETHER IT WILL CONTINUE THROUGH THE DAY. WHILE LOW LEVEL FLOW
AND ASSOCIATED ISENTROPIC FORCING AND MOISTURE ADVECTION DO DECREASE
DURING THE MORNING HOURS...LOOKS LIKE THERE IS DECENT AGREEMENT THAT
FORCING WILL REMAIN STRONG FOR AT LEAST A FEW HOURS WEDNESDAY
MORNING...AND WITH PV ANOMALY JUST NORTH OF THE KS/NE BORDER THINK
HOLDING ONTO POPS WARRANTED AT LEAST THROUGH THE MORNING HOURS. WITH
FLOW ALOFT BECOMING MORE WESTERLY AND PARALLEL TO
ISOTHERMS...FORCING SHOULD CONTINUE TO DECREASE THROUGH THE
AFTERNOON AND EARLY EVENING WHICH SHOULD BRING AN END TO THE
PRECIPITATION THREAT...ALTHOUGH A SIMILAR WAA PATTERN REDEVELOPS
OVERNIGHT ACROSS SW KANSAS WHICH MAY ALLOW FOR A STRAY STORM OR TWO
TO DEVELOP OVERNIGHT. ASIDE FROM PRECIPITATION...OTHER BIG CONCERN
WILL BE FOR POTENTIALLY COLD DAY ACROSS MUCH OF THE CWA AS SFC HIGH
BUILDS INTO THE AREA...LIKELY KEEPING CWA UNDER POTENTIALLY THICK
STRATUS DECK THROUGH THE DAY. BOTH SREF/GEFS MEANS ONLY BRING HIGHS
TO AROUND 70 IN THE NORTHEAST CORNER OF THE CWA...AND GIVEN OVERALL
PATTERN THAT MAY NOT BE OUT OF THE QUESTION. THE TEMPS WILL DEPEND
GREATLY ON HOW MUCH CLOUD COVER THERE IS AND WHILE IT IS POSSIBLE
THAT THERE WILL BE LITTLE DIURNAL SWING AS THE NAM SUGGEST...ANY
BREAKS IN CLOUDS WOULD ALLOW TEMPS TO RECOVER SO NOT QUITE READY TO
GO WITH  JUST A FEW DEGREE DIURNAL CURVE AT THIS MOMENT (PER NAM AND
REGIONAL GEM).

THURSDAY-FRIDAY...OVERALL PATTERN REMAINS FAIRLY SIMILAR TO THE PAST
FEW DAYS WITH FAIRLY ZONAL/PROGRESSIVE FLOW ALOFT ALLOWING ANOTHER
SHORT WAVE TROUGH TO SLIDE ACROSS THE NORTHERN PLAINS...FORCING
ANOTHER COLD FRONT ACROSS THE CWA...EVENTUALLY SETTLING TO THE SOUTH
OF THE CWA BY FRIDAY NIGHT. WHILE PATTERN REMAINS SIMILAR TO EARLIER
IN THE WEEK...AIRMASS IN ADVANCE OF THIS FRONT WILL BE DIFFERENT
WITH STRONG CINH EXPECTED IN ADVANCE OF FRONT. WHILE CANNOT RULE OUT
A STORM OR TWO OVERNIGHT THURSDAY AND ALONG THE FRONT ON FRIDAY...DO
NOT THINK PRECIPITATION WILL BE AS WIDESPREAD AS TUESDAY NIGHT. WHILE
AFTERNOON HIGHS SHOULD WARM DURING THE PERIOD..AM HESITANT TO GO TO
WARM GIVEN EXPECTED SFC FLOW DOES NOT REALLY LOOK FAVORABLE FOR
ADVECTING A SIGNIFICANTLY WARMER AIRMASS INTO THE AREA DURING THE
PERIOD.

SATURDAY-MONDAY...NO MAJOR CHANGES PLANNED AT THIS TIME.

JRM
&&

.AVIATION...
1110 AM MDT TUE AUG 9 2011

FOR THE 18Z TAFS...THUNDERSTORMS HAVE BEGUN BUILDING SOUTHWARD AND
APPROACHING THE REGION...AND THIS TREND IS EXPECTED TO CONTINUE INTO
THE AFTERNOON AS INSTABILITY INCREASES FURTHER. A COLD FRONT WILL
ENTER THE REGION FROM THE NORTH THIS EVENING...AND CURRENTLY STORMS
ARE OCCURRING AHEAD OF THE SHORTWAVE TROUGH MOVING GENERALLY
SOUTHEASTWARD. THE PATH OF THE TROUGH WILL MAKE KMCK MORE LIKELY TO
SEE THUNDERSTORMS BEFORE KGLD THIS AFTERNOON...AND KMCK WILL
CONTINUE TO BE MORE LIKELY TO SEE ACTIVITY INTO THE EVENING. WINDS
WILL BACK AND TAKE ON MORE OF AN EASTERLY COMPONENT...THOUGH
THUNDERSTORM OUTFLOW WILL CAUSE VARIABILITY IN THE WIND FIELD.
THUNDERSTORM ACTIVITY SHOULD DECREASE LATE IN THE EVENING AND
RAINFALL WILL INCREASE...AND MODELS SUGGEST THAT RAINFALL SHOULD BE
HEAVIER AT KMCK THAN KGLD. HAVE BROUGHT IN IFR CONDITIONS AT KMCK
SOONER THAN AT KGLD...AND SOUNDINGS SUGGEST THAT THE IFR CEILINGS
SHOULD CONTINUE INTO THE LATE MORNING.

CJS
&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GOODLAND KS
1034 AM MDT TUE AUG 9 2011

COZ090>092-KSZ001>004-013>016-027>029-041-042-NEZ079>081-101200-
YUMA-KIT CARSON-CHEYENNE CO-CHEYENNE KS-RAWLINS-DECATUR-NORTON-
SHERMAN-THOMAS-SHERIDAN-GRAHAM-WALLACE-LOGAN-GOVE-GREELEY-WICHITA-
DUNDY-HITCHCOCK-RED WILLOW-
1034 AM MDT TUE AUG 9 2011 /1134 AM CDT TUE AUG 9 2011/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EXTREME SOUTHWEST
NEBRASKA...NORTHWEST KANSAS AND EAST CENTRAL COLORADO.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS THE AREA THIS AFTERNOON
AND EVENING. VERY LARGE HAIL AND DAMAGING WIND GUSTS ARE POSSIBLE
WITH ANY STORM THAT FORMS. A FEW TORNADOES ARE POSSIBLE DURING THE
AFTERNOON AND EVENING HOURS MAINLY EAST OF A YUMA TO SHARON
SPRINGS LINE. LOCALLY HEAVY RAIN IS POSSIBLE WITH THESE STORMS
WITH THE THREAT INCREASING DURING THE OVERNIGHT HOURS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THUNDERSTORMS WILL BE POSSIBLE ACROSS THE AREA THROUGH THE
WEEKEND. A FEW SEVERE STORMS WILL BE POSSIBLE THROUGH THE
PERIOD...WITH THE BEST CHANCES ON FRIDAY AND SATURDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS EXPECTED AFTER 1 PM MDT (2 PM CDT).

CJS/JRM

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GOODLAND KS
229 PM MDT TUE AUG 9 2011

NEZ080-081-092130-
HITCHCOCK-RED WILLOW-
329 PM CDT TUE AUG 9 2011

...THE NATIONAL WEATHER SERVICE IN GOODLAND HAS ISSUED A SIGNIFICANT
WEATHER ADVISORY FOR HITCHCOCK COUNTY IN SOUTHWEST NEBRASKA AND RED
WILLOW COUNTY IN SOUTHWEST NEBRASKA...

AT 228 PM MDT/328 PM CDT/...NATIONAL WEATHER SERVICE DOPPLER RADAR
WAS TRACKING A STRONG THUNDERSTORM 14 MILES NORTH OF HAYES CENTER...
OR 25 MILES NORTH OF PALISADE...MOVING SOUTHEAST AT 35 MPH.

GOLF BALL SIZE HAIL...AND WINDS TO 55 MPH ARE EXPECTED WITH THIS
STORM.

PEOPLE IN NORTHEASTERN HITCHCOCK AND NORTHWESTERN RED WILLOW
COUNTIES...SHOULD MONITOR THE WEATHER SITUATION CLOSELY. A WARNING
MAY BE NEEDED IF THE STORMS MOVE INTO THE AREA. BE READY TO SEEK
SHELTER IF SEVERE WEATHER THREATENS.

&&

LAT...LON 4020 10040 4005 10079 4035 10096 4036 10054
TIME...MOT...LOC 2030Z 329DEG 32KT 4069 10100

THEDE