Wind Advisory 16, NWS Topeka, KS

000 
WWUS73 KTOP 291702
NPWTOP

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE TOPEKA KS
1202 PM CDT SAT SEP 29 2007

...VERY WINDY CONDITIONS WILL DEVELOP TODAY ACROSS NORTH CENTRAL
KANSAS...

.A STRONG UPPER LEVEL TROUGH OF LOW PRESSURE WILL MOVE EAST
TOWARDS THE CENTRAL PLAINS TONIGHT. AS THE UPPER TROUGH OF LOW
PRESSURE APPROACHES A SURFACE LOW PRESSURE CENTER WILL DEEPEN
ACROSS EASTERN COLORADO. IN RESPONSE TO THE DEEPENING SURFACE LOW
PRESSURE CENTER OVER EASTERN COLORADO A TIGHT PRESSURE GRADIENT
WILL DEVELOP ACROSS WESTERN AND CENTRAL KANSAS THIS AFTERNOON AND
CAUSE SOUTHERLY SURFACE WINDS TO INCREASE ABOVE 30 MPH. WIND
GUSTS OF UP TO 45 MPH WILL ALSO BE POSSIBLE. THE SURFACE WINDS
SHOULD DECREASE UNDER 30 MPH THIS EVENING.

KSZ009-021-035-300000-
/O.EXA.KTOP.WI.Y.0016.000000T0000Z-070930T0000Z/
WASHINGTON-CLAY-DICKINSON-
INCLUDING THE CITIES OF...CLAY CENTER...ABILENE
1202 PM CDT SAT SEP 29 2007

...WIND ADVISORY IN EFFECT UNTIL 7 PM CDT THIS EVENING...

THE NATIONAL WEATHER SERVICE IN TOPEKA HAS ISSUED A WIND
ADVISORY...WHICH IS IN EFFECT UNTIL 7 PM CDT THIS EVENING. 

SURFACE WINDS WILL INCREASE TO 3O TO 35 MPH WITH GUSTS UP TO
45 MPH DURING THE LATE MORNING HOURS AND CONTINUE THROUGH THE
AFTERNOON HOURS. SURFACE WINDS SHOULD DIMINISH BELOW 30 MPH AFTER
700 PM.

A WIND ADVISORY IS ISSUED WHEN SUSTAINED WINDS ARE FORECAST TO BE
31 TO 40 MPH. WINDS THIS STRONG CAN MAKE DRIVING DIFFICULT...
ESPECIALLY FOR HIGH PROFILE VEHICLES. USE EXTRA CAUTION.

TAKE ACTION TO SECURE TRASH CANS...LAWN FURNITURE...AND OTHER
LOOSE OR LIGHTWEIGHT OUTDOOR OBJECTS.

$$

KSZ008-020-034-300000-
/O.CON.KTOP.WI.Y.0016.000000T0000Z-070930T0000Z/
REPUBLIC-CLOUD-OTTAWA-
INCLUDING THE CITY OF...CONCORDIA
1202 PM CDT SAT SEP 29 2007

...WIND ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...

A WIND ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING. 

SURFACE WINDS WILL INCREASE TO 3O TO 35 MPH WITH GUSTS UP TO
45 MPH DURING THE LATE MORNING HOURS AND CONTINUE THROUGH THE
AFTERNOON HOURS. SURFACE WINDS SHOULD DIMINISH BELOW 30 MPH AFTER
700 PM.

A WIND ADVISORY IS ISSUED WHEN SUSTAINED WINDS ARE FORECAST TO BE
31 TO 40 MPH. WINDS THIS STRONG CAN MAKE DRIVING DIFFICULT...
ESPECIALLY FOR HIGH PROFILE VEHICLES. USE EXTRA CAUTION.

TAKE ACTION TO SECURE TRASH CANS...LAWN FURNITURE...AND OTHER
LOOSE OR LIGHTWEIGHT OUTDOOR OBJECTS.

$$

000 
WWUS73 KTOP 292349
NPWTOP

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE TOPEKA KS
649 PM CDT SAT SEP 29 2007

KSZ008-009-020-021-034-035-300100-
/O.EXP.KTOP.WI.Y.0016.000000T0000Z-070930T0000Z/
REPUBLIC-WASHINGTON-CLOUD-CLAY-OTTAWA-DICKINSON-
INCLUDING THE CITIES OF...CONCORDIA...CLAY CENTER...ABILENE
649 PM CDT SAT SEP 29 2007

...WIND ADVISORY WILL EXPIRE AT 7 PM CDT THIS EVENING...

SOUTH WINDS HAVE RELAXED SLIGHTLY ACROSS NORTH CENTRAL KANSAS.
THEREFORE THE WIND ADVISORY WILL EXPIRE AT 7 PM CDT THIS EVENING.
HOWEVER WINDY CONDITIONS WILL PERSIST THROUGH THE NIGHT WITH WINDS
STAYING UP AROUND 20 MPH WITH GUSTS AS HIGH AS 35 MPH.

$$

WOLTERS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
400 PM CDT FRI SEP 28 2007

.DISCUSSION...

WATER VAPOR IMAGERY SHOWING SHORTWAVE MOVING NORTHEAST INTO NEW
ENGLAND...WHILE A PRONOUNCED UPPER LEVEL WAVE CONTINUED TO MOVE ONTO
THE WESTERN CONUS.  UPPER LEVEL RIDGE AXIS WAS OVER THE WESTERN
MISSOURI VALLEY...WITH SURFACE HIGH PRESSURE ENTERING GREAT LAKES
REGION.  SURFACE PRESSURE WAS FALLING OVER THE CENTRAL PLAINS...AS
LEE SIDE TROF DEEPENED.

HIGH CLOUDS WILL FILTER INTO THE AREA THIS EVENING...IN ADVANCE OF
THE UPPER LEVEL WAVE.  ISENTROPIC SURFACES SHOWING AN INCREASE IN
MID LEVEL MOISTURE...USHERING IN MID LEVEL CLOUDS AFTER DARK.
PRESSURE GRADIENT WILL CONTINUE TO TIGHTEN AS SHORTWAVE STRENGTHENS
OVER THE ROCKIES.  WINDS WILL STAY UP OVERNIGHT...ESPECIALLY IN
WESTERN ZONES.  RESULTANT MIXING AND INCREASING CLOUD COVER WILL
HELP LOW TEMPERATURES STAY UP TONIGHT...AND WILL BE MUCH WARMER OVER
THE ENTIRE FORECAST AREA...AS MORE LOW LEVEL MOISTURE RIDES IN
SOUTHERLY WINDS.

CLOUD COVER TOMORROW WILL GRADUALLY INCREASE TOMORROW AS THE UPPER
LEVEL SYSTEM NEARS...BUT SOUTHEAST ZONES WILL STILL REMAIN MOSTLY
SUNNY.  INCREASING SOUTHERLY WINDS OVER WESTERN COUNTIES MAY WARRANT
ISSUANCE OF A WIND ADVISORY.  THICKER CLOUD COVER MAY INHIBIT MIXING
SOMEWHAT...BUT WITH LOWER LEVEL WINDS BEING RELATIVELY
UNIDIRECTIONAL...AND 850 WINDS APPROACHING 50 KTS...MECHANICAL
MIXING MAY MORE THAN MAKE UP FOR IT.  STILL...LEFT FOR LATER SHIFTS
TO DECIDE AS I HAVE A BIT OF UNCERTAINTY.

SATURDAY NIGHT THROUGH MONDAY...STRONG UPPER TROUGH PUSHES INTO THE
CENTRAL PLAINS SATURDAY NIGHT BRINGING ABOUT A COMPLEX WEATHER
SCENARIO.  MODELS HAVE TRENDED FASTER WITH THIS SYSTEM...AND HAVE
PLACED THE TROUGH AXIS FURTHER NORTH THAN WHAT WAS FORECAST 24 HRS
AGO.  TROUGH LOOKS TO REMAIN NEUTRALLY TILTED AS IT ENTERS THE
PLAINS...AND THEN BECOME SLIGHTLY NEGATIVELY TILTED AS IT PUSHES
EAST NORTHEAST THROUGH NEBRASKA.  AS THE SYSTEM PUSHES EAST IT WILL
SEND A PACIFIC FRONT/DRYLINE EAST SOUTHEAST THROUGH THE CENTRAL
PLAINS.  ALL MODELS CONSISTENT IN BRINGING STRONG CONVERGENCE AND
VERTICAL MOTION ALONG THE AXIS OF THE FRONT.  WITH THE POSITION OF
THE UPPER LEVEL TROUGH FURTHER NORTH...THE BEST LARGE SCALE ASCENT
WILL BE FOCUSED FURTHER NORTH.  MODELS ALSO BRINGING DECENT DRY SLOT
NEAR THE FRONTAL BOUNDARY AS IT MOVES THROUGH THE FORECAST AREA.
WHILE SHEAR PARAMETERS LOOK TO BE EXCELLENT FOR SUPPORTING ORGANIZED
CONVECTION...THE QUICKER PASSAGE OF THE SYSTEM WOULD LIMIT THE
POTENTIAL INSTABILITY AS CONVECTION WILL LIKELY DEVELOP AROUND OR
BEFORE SUNSET AND BRING CLOUD COVER OVER THE CWA BEFORE GOOD DAYTIME
HEATING CAN SIGNIFICANTLY DESTABILIZE THE WARM SECTOR.  WITH LIMITED
INSTABILITY WOULD ANTICIPATE THE BETTER CHANCES FOR SEVERE WEATHER
TO EXIST NORTHEAST OF THE FORECAST AREA HERE.  MODELS ARE HANGING
ONTO A NARROW BAND OF INSTABILITY RIGHT ALONG THE FRONTAL BOUNDARY
HOWEVER...POSSIBLY DUE TO DRY SLOT MENTIONED EARLIER ALLOWING FOR
SOME BETTER DAYTIME HEATING AND DESTABILIZATION IN THE VICINITY OF
THE BOUNDARY.  RIGHT ALONG THE FRONTAL BOUNDARY THE LOW LEVEL WINDS
ARE VEERED SO THAT SHEAR PROFILE IS NEARLY UNIDIRECTIONAL...SO IF
CONVECTION MANAGES TO ORGANIZE WOULD EXPECT THE PRIMARY SEVERE
WEATHER TO BE IN THE FORM OF LINEAR MCS ACTIVITY...PRODUCING
PRIMARILY DAMAGING OUTFLOW WINDS.  IF THE SYSTEM IS ACTUALLY SLOWER
THAN FORECAST...INCREASED INSTABILITY AHEAD OF THE FRONTAL BOUNDARY
COMBINED WITH BACKED LOW LEVEL WINDS WOULD ALLOW THE ENTIRE SPECTRA
OF SEVERE THUNDERSTORMS TO OCCUR.  FOR NOW WITH 12Z ECMWF/GFS/NAM
ALL INDICATING FRONTAL PASSAGE THROUGH MUCH OF THE CWA SUNDAY
MORNING EXPECT ORGANIZED CONVECTION TO PROVIDE ONLY MARGINAL SEVERE
THREAT.

BEHIND THIS FRONTAL BOUNDARY MODELS ARE CONSISTENT IN BRINGING A
VERY DRY AIRMASS INTO PLACE FOR SUNDAY AFTERNOON THROUGH THE
OVERNIGHT HOURS.  MODELS HAVE TD VALUES IN THE 30S DIRECTLY BEHIND
THE FRONT...AND THEN IN GENERAL IN THE LOWER 40S WELL BEHIND THE
FRONT.  WITH SURFACE RIDGE BUILDING IN BEHIND THE FRONT DO NOT
EXPECT WINDS STRONG ENOUGH TO PROVIDE A SIGNIFICANT FIRE DANGER
THREAT TO THE FORECAST AREA LATE SUNDAY AFTERNOON OR EVENING.
HOWEVER WITH RH VALUES LIKELY APPROACHING THE 20 PERCENT CRITERIA
FOR RED FLAG WARNING...WINDS DIRECTLY BEHIND THE FRONT MAY BE
GUSTY...BUT AS MENTIONED WITH SURFACE RIDGE BUILDING IN BEHIND THE
FRONT DO NOT SEE WINDS REMAINING ABOVE RED FLAG CRITERIA FOR THE 3
HOURS REQUIRED TO NEED A RED FLAG WARNING.  RAIN COOLED AIR...AND
COLD AIR ADVECTION MAY ALSO LIMIT THE MIN RH VALUES FROM DIPPING
BELOW 20 PERCENT FOR AN EXTENDED PERIOD OF TIME.

SURFACE HIGH WILL PUSH EAST THROUGH KS OVERNIGHT SUNDAY BRINGING
RETURN FLOW AND QUICK MOISTURE RECOVERY THROUGH THE CWA FOR MONDAY.
QUICK RETURN FLOW COULD PROVIDE ENOUGH ISENTROPIC LIFT/MOISTURE
CONVERGENCE TO BRING ABOUT THE POSSIBILITY OF CONVECTION THROUGH
CENTRAL KS MONDAY AFTERNOON...BUT AT THIS TIME FAVORING LARGE SCALE
RIDGING AND KEEPING SKIES MOSTLY SUNNY ATM.  ISENTROPIC LIFT AND
MOISTURE CONVERGENCE WILL BE SOMETHING TO KEEP AN EYE ON IN FUTURE
FORECAST PACKAGES...BUT FOR NOW STICKING TO LARGER SCALE FEATURES
SEEMS THE WAY TO GO.

TUES-FRI...MAIN FORECAST CONCERN IN THIS PERIOD IS FRONTAL PASSAGE
TUESDAY. SECOND TROUGH OF THE WEEK TO TRAVERSE THE CENTRAL PLAINS IN
RELATIVELY BUSY PATTERN ARRIVES TUESDAY MORNING. WEEKEND TROUGH
SERVES TO PULL MIDLEVEL MOISTURE FROM THE SOUTHWEST TO THE PLAINS.
ASSOCIATED COOL FRONT TO SLINK SOUTHWARD...THEN SLIP BACK NORTHWARD
MONDAY AS A WARM FRONT. MOIST SOUTHWESTERLY FLOW QUICK TO RETURN TO
THE PLAINS...AND LINGERING MOISTURE IN THE VICINITY OF THIS FRONT
WILL HELP TO PRIME THE ENVIRONMENT AHEAD OF TUESDAY TROUGH. TWO
ITEMS IMPROVE CONFIDENCE IN AT LEAST RAINFALL AND POTENTIAL SEVERE
WEATHER THREAT FOR TUESDAY.  FIRST...SIGNIFICANTLY MORE MIDLEVEL
MOISTURE IS AVAILABLE IN THIS TIME FRAME THAN FOR THE WEEKEND
SYSTEM. SECOND...28/12Z GFS HAS SLOWED A BIT...WHICH BRINGS THE
PASSAGE OF THE MAIN 500HPA TROUGH MORE IN LINE WITH ECMWF...WHICH
GENERALLY HAS BEEN THE SLOWER OF THE MODEL SOLUTIONS FOR THE PAST 48
HOURS WITH THIS FEATURE. BUT...A FEW FLIES IN THE OINTMENT PREDICATE
A MORE BENIGN...BUT FAIRLY WIDESPREAD RAINFALL EVENT LOCALLY. FIRST
ISSUE IS TIME OF DAY. SFC FRONT ATTM LOOKS TO ENTER THE CWA BETWEEN
12Z AND 18Z TUESDAY MORNING...REACHING THE TOPEKA AREA JUST BEFORE
00Z. SHOULD THE EAST CENTRAL PART OF THE STATE SEE A BIT OF
AFTERNOON SUNSHINE...ATMOSPHERE MAY BE ABLE TO DESTABILIZE ENOUGH TO
PROMOTE CONVECTIVE DEVELOPMENT WITH THE FROPA. BUT...OVERNIGHT
PRE-FRONTAL CLOUDINESS IS POSSIBLE STEMMING FROM ISENTROPIC LIFT
OVER WARM FRONT AHEAD OF THE MAIN TROUGH AXIS. ECMWF ALSO SOMEWHAT
WEAKER WITH THE 500HPA TROUGH...WHILE THE GFS KEEPS MAIN
CONVERGENCE/LIFT NORTH OF THE CWA. IN OTHER WORDS...DETAILS STILL
HARD TO PINPOINT ATTM...AND OPTED ONLY TO SLIGHTLY INCREASE THE
CHANCE FOR PRECIPITATION DURING THE 12Z TUE TO 00Z WED TIME FRAME
WHEN CONFIDENCE IN CHANCE FOR INGREDIENTS TO ALIGN IS GREATEST.

ONE OTHER INTERESTING FEATURE OF NOTE BEGINS TO TAKE SHAPE LATE
MONDAY NIGHT...BUT THE EFFECTS MAY IMPACT THE LONGER RANGE FORECAST.
NORTHERN PORTION OF 500HPA HIGH OVER THE SOUTHEAST U.S.GRADUALLY
BEGINS TO TILT EASTWARD IN PROGRESSIVE FLOW PATTERN AHEAD OF THE
MIDWEEK TROUGH. THIS EFFECTIVELY CLOSES OFF A PIECE OF ENERGY FROM
THE WEEKEND SYSTEM OVER THE ATLANTIC COAST. THIS THEN SOMEWHAT
RETROGRADES WESTWARD...WHICH SERVES TO AMPLIFY THE RIDGE AHEAD OF
THE MIDWEEK SYSTEM. THIS SHOULD SOMEWHAT SLOW THE FORWARD SPEED OF
THE TROUGH...BUT THE NEGATIVE TILT THE TROUGH TAKES ON MAY ACTUALLY
SERVE TO SPEED UP THE SOUTHERN EDGE OF THE SYSTEM. WILL BE
INTERESTING TO SEE HOW THIS PLAYS OUT OVER THE NEXT FEW DAYS.

LIPPMAN/CAVANAUGH/KONOP

&&

.AVIATION...

VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HOURS...WHILE MID AND
HIGH CLOUDS WILL INCREASE AFTER DARK.  WINDS COULD BECOME AN ISSUE
TOMORROW.  AFTER A DIP IN SPEEDS EARLY TONIGHT...TIGHTENING PRESSURE
GRADIENT WILL PUSH SPEEDS UP TOMORROW MORNING...ESPECIALLY OVER THE
WESTERN PORTION OF ROUTES...WHERE GUSTS OVER 30 MPH ARE LIKELY IN
THE AFTERNOON.

LIPPMAN

&&

.TOP WATCHES/WARNINGS/ADVISORIES...NONE.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TOPEKA KS
1040 PM CDT FRI SEP 28 2007

KSZ008>012-020>024-026-034>040-054>056-058-059-300345-
REPUBLIC-WASHINGTON-MARSHALL-NEMAHA-BROWN-CLOUD-CLAY-RILEY-
POTTAWATOMIE-JACKSON-JEFFERSON-OTTAWA-DICKINSON-GEARY-MORRIS-
WABAUNSEE-SHAWNEE-DOUGLAS-LYON-OSAGE-FRANKLIN-COFFEY-ANDERSON-
1040 PM CDT FRI SEP 28 2007

THIS HAZARDOUS WEATHER OUTLOOK IS FOR EAST CENTRAL...NORTH
CENTRAL AND NORTHEAST KANSAS.

.DAY ONE...TONIGHT

A FEW THUNDERSTORMS ARE POSSIBLE ACROSS NORTH CENTRAL
OVERNIGHT...GENERALLY NORTH OF A MINNEAPOLIS TO MARYSVILLE
LINE.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

SOUTHERLY WINDS ARE EXPECTED TO INCREASE TO 20 TO 30 MPH WITH
GUSTS TO 40 MPH THROUGH NORTH CENTRAL KANSAS SATURDAY. A WIND
ADVISORY MAY BE NEEDED ACROSS PORTIONS OF NORTH CENTRAL KANSAS FOR
SATURDAY AFTERNOON.

THUNDERSTORMS ARE POSSIBLE ACROSS PORTIONS OF NORTH CENTRAL AND
NORTHEAST KANSAS SATURDAY NIGHT. SOME OF THESE STORMS MAY BE
SEVERE SATURDAY NIGHT. DAMAGING OUTFLOW WINDS ARE EXPECTED TO BE
THE PRIMARY HAZARD ASSOCIATED WITH ANY SEVERE THUNDERSTORM.

THUNDERSTORMS ARE POSSIBLE ACROSS THE ENTIRE OUTLOOK AREA ON
SUNDAY. SOME OF THESE THUNDERSTORMS MAY ALSO BE SEVERE ON SUNDAY
WITH DAMAGING OUTFLOW WINDS REMAINING THE PRIMARY HAZARD
ASSOCIATED WITH ANY SEVERE STORM.

THERE IS ANOTHER CHANCE OF THUNDERSTORMS ACROSS THE ENTIRE OUTLOOK AREA
MONDAY NIGHT THROUGH TUESDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS SHOULD NOT BE NEEDED TONIGHT.