Flash Flood Warning 59, NWS Topeka, KS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
425 AM CDT FRI JUN 29 2007

.DISCUSSION...

LATEST WATER VAPOR SATELLITE AND 00Z UPPER AIR MAPS SHOWED A TROUGH
AXIS AT 700-500MB EXTENDED FROM CENTRAL TX...NORTHEAST ACROSS
SOUTHEAST KS INTO CENTRAL MO. A STRONGER UPPER TROUGH WAS LOCATED
JUST OFF SHORE ACROSS THE PACIFIC NORTHWEST. A UPPER RIDGE WAS
LOCATED ACROSS THE NORTHERN PLAINS. A BROAD UPPER RIDGE WAS LOCATED
ACROSS THE DESSERT SOUTHWEST EXTENDING NORTHEAST ACROSS CENTRAL AND
SOUTHERN HIGH PLAINS.

850MB ANALYSIS ALONG WITH PROFILERS SHOWED A FRONT EXTENDING FROM
WESTERN OK NORTHEAST ACROSS EXTREME SOUTHEAST KS INTO CENTRAL OK. A
BROAD BAND OF LIGHT TO MODERATE RAINFALL WAS LOCATED ALONG AND
SOUTHEAST OF THE FRONT AT 850MB. THE 00Z TOP SND SHOWED DRIER
NORTHEAST PARCEL TRAJECTORIES FROM ABOVE 900MB. ALSO DRIER
TRAJECTORIES WERE NOTED IN THE MID LEVELS ON THE NORTH SIDE OF THE
700-500MB TROUGH AXIS. THE SHORT RANGE MODELS SHOW THE 850MB WINDS
VEERING ACROSS THE CWA THIS MORNING. AS THE 850MB WINDS VEER MORE TO
THE SOUTHEAST...DEEPER TROPICAL MOISTURE MAY ADVECT FARTHER
NORTHWEST AND CAUSE THE BAND OF MODERATE TO HEAVY RAINFALL TO EXPAND
FARTHER NORTHWEST ACROSS THE SOUTH CENTRAL AND EAST CENTRAL COUNTIES
OF THE CWA THROUGH THE MORNING HOURS. THE NAM MODEL SHOWS THE
HEAVIER PRECIP REAMING ALONG AND SOUTH OF AN EMPORIA TO LAWRENCE
LINE...WHILE THE GFS FORECAST HEAVIER PRECIP DEVELOPING AS FAR
NORTHWEST AS A COUNCIL GROVE TO TOPEKA TO HIAWATHA LINE THROUGH NOON
TODAY. BASED OFF OF CURRENT RADAR TRENDS THE HEAVIER PRECIP IS
BEGINNING TO DEVELOP FARTHER WEST INTO ICT AND NORTHWEST OK. THIS
HEAVY RAIN MAY MOVE FARTHER NORTH ACROSS THE CWA TO A COUNCIL GROVE
TO TOPEKA LINE.  IM LEANING MORE TOWARDS THE GFS SOLUTION AND WILL
EXPAND THE CURRENT FLASH FLOOD WATCH NORTH A ROW OF COUNTIES AND
EXTEND THE WATCH THROUGH 700 AM ON SATURDAY MORNING. THE NAM WEAKENS
THE MID-LEVEL TROUGH OVER EASTERN KS THIS AFTERNOON WHILE THE
SOUTHERN SECTION OF THE MID-LEVEL TROUGH DEEPENS ACROSS OK AND NORTH
TX. THIS RESULTS IN THE HEAVIER RAIN BAND ACROSS SOUTHEAST KS
BREAKING UP INTO AN AREA OF SCATTERED SHOWERS. NOT TOO CONFIDENT IN
THE NAM FCST PAST 18Z TODAY GIVEN DEEP MOISTURE IN PLACE AND ANY
WEAK LIFT WILL KEEP THE HEAVY RAIN BANDS DEVELOPING ACROSS THE
SOUTHERN...SOUTHEAST AND EAST CENTRAL COUNTIES. I PROBABLY WILL KEEP
THE BEST CHANCE FOR RAIN SOUTH OF I-70...SOME OF THE RAINFALL WILL
BE MODERATE TO HEAVY AT TIMES AND SINCE THE GROUND IS
SATURATED...ANY ADDITIONAL HEAVY RAINFALL MAY CAUSE FLOODING OF
ROADS...RIVERS AND LOW LYING AREAS. HIGHS TODAY ACROSS THE SOUTHERN
AND EASTERN COUNTIES WILL ONLY REACH THE LOWER TO MID 70S GIVEN
CLOUD COVER AND PERIODS OF RAINFALL. THERE MAY BE SOME SUN THROUGH
THE HIGH CLOUDS ACROSS THE NORTHWEST COUNTIES TO HELP WARM
TEMPERATURES INTO THE LOWER 80S.

TONIGHT AND SATURDAY...THE MID-LEVEL TROUGH AXIS WILL CONTINUE TO
HOLD IN PLACE. I EXPANDED THE RAIN CHANCES ACROSS THE ENTIRE CWA
TONIGHT SINCE 850MB WINDS WILL VEER AROUND TO THE SOUTH AND
TRANSPORT DEEPER MOISTURE NORTH ACROSS THE CWA. THE HEAVIER
RAINFALL MAY CONTINUE ALONG AND SOUTH OF THE KS TURNPIKE THROUGH THE
EVENING HOURS. THE NAM SOLUTION SHOW THE MORE AMPLIFIED SECTION OF
THE MID-LEVEL TROUGH ACROSS WESTERN OK AND KEEPS MOST OF THE QPF
SOUTHWEST OF THE CWA.  THE GFS IS MORE AMPLIFIED WITH THE THE
MID-LEVEL TROUGH ACROSS THE CWA AND THAT COULD LEAD TO AN INCREASE
IN RAIN CHANCES ACROSS THE CENTRAL AND EASTERN COUNTIES OF THE CWA
WITH THE POTENTIAL FOR HEAVY RAINFALL. ON SATURDAY THE 5H RIDGE
ACROSS THE DESSERT SOUTHWEST WILL TRY TO AMPLIFY NORTHEAST INTO THE
CENTRAL PLAINS. THE AMPLIFICATION OF THE 5H RIDGE MAY CAUSE THE
MID-LEVEL TROUGH TO REDEVELOP FARTHER SOUTHWEST ACROSS WESTERN OK.
THIS MAY BRING AN END TO THE STEADY RAINFALL...HOWEVER AFTERNOON
SHOWERS AND THUNDERSTORMS MAY DEVELOP ACROSS THE SOUTHEAST COUNTIES
IF THE CLOUDS BREAK ENOUGH FOR SURFACE HEATING TO DEVELOP. HIGHS ON
SATURDAY WILL BE DEPENDENT ON CLOUD COVER...IF THE EASTERN COUNTIES
REMAIN MOSTLY CLOUDY HIGHS WILL ONLY REACH THE MID AND UPPER 70S.
THERE SHOULD BE MORE SUN ACROSS THE NORTHWEST COUNTIES WITH HIGHS IN
THE LOWER 80S.

SUNDAY THROUGH TUESDAY...THE 5H RIDGE AXIS SHOULD EXPAND FARTHER
EAST ACROSS THE CENTRAL PLAINS. THERE MAY BE SOME AFTERNOON SHOWERS
SUNDAY AND MONDAY ACROSS THE SOUTHEAST COUNTIES. HIGH TEMPERATURES
SHOULD WARM INTO THE 80S ON SUNDAY WITH LOWER TO MID 90S BY TUESDAY.
A 5H TROUGH WILL MOVE EAST ACROSS THE NORTHERN PLAINS BY MID WEEK.
THIS MAY CAUSE A FRONT TO MOVE SOUTH ACROSS THE CWA ON THURSDAY
PROVING THE AREA WITH A CHANCE OF SHOWERS AND THUNDERSTORMS. THE
CURRENT EXTENDED FORECAST GRIDS LOOK GOOD AND NO CHANGES WERE MADE

&&

.AVIATION...

CEILINGS CONTINUE TO LOWER AS PRECIPITATION SHIELD LIFTS MORE
NORTHWARD WITH TIME. EXPECT PERIODS OF SHOWERS FOR THE MAJORITY OF
THE DAY OVER TOPEKA AND VICINITY WITH CEILINGS BROKEN/OVERCAST
BETWEEN 1-3K WITH LOCALLY LOWER VALUES IN PRECIPITATION REGIONS.
VISIBILITY WILL AVERAGE 6-10 MILES WITH MUCH LOWER VALUES IN
PRECIPITATION REGIONS. FOR ADDITIONAL DETAILS...REFER TO SHORT TERM
FORECAST DISCUSSION SECTION.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...FLASH FLOOD WATCH THROUGH 7 AM
SATURDAY FOR KSZ37>40-054>056-058-059.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TOPEKA KS
453 AM CDT FRI JUN 29 2007

KSZ008>012-020>024-026-034>040-054>056-058-059-301100-
REPUBLIC-WASHINGTON-MARSHALL-NEMAHA-BROWN-CLOUD-CLAY-RILEY-
POTTAWATOMIE-JACKSON-JEFFERSON-OTTAWA-DICKINSON-GEARY-MORRIS-
WABAUNSEE-SHAWNEE-DOUGLAS-LYON-OSAGE-FRANKLIN-COFFEY-ANDERSON-
453 AM CDT FRI JUN 29 2007

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

.DAY ONE...TODAY AND TONIGHT

A FLASH FLOOD WATCH IS IN EFFECT THROUGH 700 AM SATURDAY ALONG AND
SOUTH OF A COUNCIL GROVE...TO TOPEKA...TO LAWRENCE LINE. PERIODS
OF RAIN AND ISOLATED THUNDERSTORMS MAY PRODUCE HEAVY RAINFALL. THE
HEAVY RAIN MAY CAUSE FLOODING OF COUNTY ROADS...RIVERS AND LOW-LYING
AREAS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

THERE IS A SLIGHT CHANCE OF THUNDERSTORMS ACROSS THE ENTIRE AREA
ON SATURDAY.

ISOLATED THUNDERSTORMS MAY BE POSSIBLE SOUTH OF INTERSTATE 35 SUNDAY
AFTERNOON.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS ARE ENCOURAGED TO REPORT RAINFALL AMOUNTS OVER ONE INCH
TO THE NATIONAL WEATHER SERVICE IN TOPEKA.