Severe Thunderstorm Warning 168, NWS Topeka, KS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
345 PM CDT Sat Sep 20 2014

.SHORT TERM...(This Evening through Sunday)
Issued at 343 PM CDT SAT SEP 20 2014

Main focus for the short term is on the development of thunderstorms
as a cold front progresses southward through the forecast area.
Water vapor imagery showed a broad trough across the northern U.S.
with an embedded shortwave trough skimming across northeast Kansas.
This passing wave has been helping to push the cold front southward
into the area, with the boundary stretching from roughly Minneapolis
to Randolph and Hiawatha. Scattered thunderstorms had developed
along this boundary across northeast Kansas by early afternoon,
however the very pulse-y nature of these storms suggests that the
best forcing is limited to just near the boundary. While there are
still plenty of variances amongst the short-range models with the
progression of this system, in general they seem to trend toward
more scattered thunderstorms developing along and north of I-70
(i.e., along the cold front) between 20z-00z as little to no
inhibition is in place. With 2000-3000J/kg of surface-based CAPE and
generally 30-40kts of 0-6km bulk shear, some of these storms could
be strong to severe mid-afternoon through early this evening,
especially across far northeast and east central Kansas, with small
hail, gusty winds, and locally heavy rainfall being the primary
threats.  Some limiting factors though to this severe potential are
that the steep low-level lapse rates only extend up to around 800mb
and there also is a fairly narrow zone of convergence with limited
frontogenetical forcing near this boundary. Model soundings show the cap
building back into the region around or shortly after sunset, so any
storms across east central Kansas early this evening will likely
become elevated and gradually weaken and diminish in coverage
through the evening hours. While these storms should mostly be south
of the forecast area by late evening, cannot rule out a few
lingering storms into the overnight hours before clearing out.

With winds veering to the north behind the front, cooler air will
start advecting into the region with overnight low temperatures
ranging from the mid/upper 50s north to the low/mid 60s over east
central Kansas. This CAA will persist through the day with highs
only reaching into the mid/upper 70s, despite mostly sunny skies.
Dry conditions are expected through the day on Sunday as surface
high pressure comes spilling southward into the region behind the
exiting system.

.LONG TERM...(Sunday Night through Saturday)
Issued at 343 PM CDT SAT SEP 20 2014

Will maintain mostly clear/mostly sunny skies Sunday night into Monday
beneath and eastward expanding upper level ridging ahead of the
approaching intermountain west trough. With light winds and good
radiational cooling...a pleasantly cool early Fall night in the
upper 40s to lower 50s still looks on track. With the cool start to
the day...light southeast winds and a very slow increase in clouds
late in the day...will keep highs in the middle 70s..although
stronger mixing and more veered llvl winds could lead to a little
warmer temps.

As the western trough moves eastward into the plains...then lifts
northeastward in response to amplifying eastern ridge...moisture
advection and forcing will overspread the county warning area from
west to east from late Monday night on into Tuesday night.
Precipitation chances will then be highest across the western 2/3 of
the county warning area Tuesday night into Wednesday before
decreasing as the upper trough begins to shear and weaken. Will then
go with a dry fcst for Friday on into next Saturday as upper ridge
becomes dominant across the central plains. The thicker clouds and
higher precip chances still appear will limit highs Tuesday and
Wednesday across the northern cwa to the low to middle 70s...with
highs then moderating to around 80 by Friday then continuing on into
Saturday. Lows will commonly be in the upper 50s to lower 60s
Wednesday into the weekend.

&&

.AVIATION...(For the 18Z TAFs through 18Z Sunday Afternoon)
Issued at 1221 PM CDT SAT SEP 20 2014

Isolated to scattered storms are expected to develop between 20Z and
24Z moving along a frontal boundary pushing SE through the area.
Storms may produce locally heavy rain, gusty winds, and small hail.
Confidence is high on development but lower on timing of initiation and
location of formation.  After sunset, any lingering storms should
weaken and dissipate before skies begin to clear and winds become
northerly.

&&

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

SHORT TERM...Hennecke
LONG TERM...63
AVIATION...Heller

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TOPEKA KS
338 PM CDT SAT SEP 20 2014

KSZ008>012-020>024-026-034>040-054>056-058-059-212045-
REPUBLIC-WASHINGTON-MARSHALL-NEMAHA-BROWN-CLOUD-CLAY-RILEY-
POTTAWATOMIE-JACKSON-JEFFERSON-OTTAWA-DICKINSON-GEARY-MORRIS-
WABAUNSEE-SHAWNEE-DOUGLAS-LYON-OSAGE-FRANKLIN-COFFEY-ANDERSON-
338 PM CDT SAT SEP 20 2014

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

.DAY ONE...THIS AFTERNOON AND TONIGHT.

SCATTERED THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG THE COLD
FRONT THIS AFTERNOON INTO THE EVENING HOURS. ADDITIONAL SCATTERED
THUNDERSTORMS MAY DEVELOP ALONG THE BOUNDARY ACROSS NORTHEAST AND
EAST CENTRAL KANSAS...GENERALLY ALONG AND NORTH OF I-70...THROUGH
THE REMAINDER OF THE AFTERNOON HOURS BEFORE PROGRESSING SOUTH OF
I-70 LATE AFTERNOON INTO THE EVENING HOURS. A FEW OF THESE STORMS
MAY PULSE UP AND BECOME STRONG TO SEVERE...ESPECIALLY ACROSS FAR
EAST CENTRAL KANSAS...THROUGH THE REMAINDER OF THE AFTERNOON INTO
EARLY THIS EVENING. THE PRIMARY THREATS WITH ANY STRONGER STORMS
THAT DEVELOP ARE SMALL HAIL...SOME GUSTY WINDS AND LOCALLY HEAVY
RAIN. THESE STORMS SHOULD DIMINISH IN COVERAGE AND WEAKEN THROUGH
THE EVENING HOURS AS THEY CONTINUE TO TRACK SOUTH OF THE OUTLOOK
AREA.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

THUNDERSTORMS ARE POSSIBLE IN NORTH CENTRAL KANSAS MONDAY
NIGHT...WITH CHANCES THEN SPREADING EASTWARD ACROSS THE REMAINDER
OF THE AREA BY TUESDAY NIGHT THROUGH WEDNESDAY. THUNDERSTORM
CHANCES WILL THEN LINGER ACROSS THE AREA THROUGH THURSDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS SHOULD NOT BE NEEDED THROUGH TONIGHT.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TOPEKA KS
1216 PM CDT SAT SEP 20 2014

KSZ011-201745-
NEMAHA-
1216 PM CDT SAT SEP 20 2014

...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN NEMAHA COUNTY...

THROUGH 1245 PM CDT...A CLUSTER OF THUNDERSTORMS WILL MOVE SOUTHEAST
AT 35 MPH ACROSS PORTIONS OF NORTHWESTERN NEMAHA COUNTY. NATIONAL
WEATHER SERVICE DOPPLER RADAR INDICATED THIS CLUSTER OF STORMS IS
CAPABLE OF PRODUCING PENNY SIZE HAIL...STRONG WINDS OF 40 TO 50 MPH
AND HEAVY RAIN. SOME LOCATIONS THAT COULD BE AFFECTED INCLUDE BERN
AND SENECA.

STAY ALERT TO THE WEATHER IN CASE A WARNING IS ISSUED.

&&

LAT...LON 3992 9589 3979 9609 3997 9624 4000 9624
      4000 9602
TIME...MOT...LOC 1716Z 317DEG 30KT 4003 9619

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TOPEKA KS
1247 PM CDT SAT SEP 20 2014

KSZ011-012-201815-
BROWN-NEMAHA-
1247 PM CDT SAT SEP 20 2014

...SIGNIFICANT WEATHER ADVISORY FOR NEMAHA AND WEST CENTRAL BROWN
COUNTIES...

THROUGH 115 PM CDT...A STRONG THUNDERSTORM WILL MOVE SOUTHEAST AT 40
MPH ACROSS PORTIONS OF NEMAHA AND WEST CENTRAL BROWN COUNTIES.
NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THIS STORM IS
CAPABLE OF PRODUCING NICKEL SIZE HAIL...STRONG WINDS OF 40 TO 50 MPH
AND TORRENTIAL RAINFALL. SOME LOCATIONS THAT COULD BE AFFECTED
INCLUDE WOODLAWN AND FAIRVIEW.

STAY ALERT TO THE WEATHER IN CASE A WARNING IS ISSUED.

&&

LAT...LON 3980 9563 3964 9588 3987 9613 3999 9597
TIME...MOT...LOC 1747Z 313DEG 34KT 3985 9595

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TOPEKA KS
220 PM CDT SAT SEP 20 2014

KSZ011-012-202000-
BROWN-NEMAHA-
220 PM CDT SAT SEP 20 2014

...SIGNIFICANT WEATHER ADVISORY FOR EASTERN NEMAHA AND SOUTHWESTERN
BROWN COUNTIES...

THROUGH 300 PM CDT...A THUNDERSTORM WILL MOVE SOUTHEAST AT 25 MPH
ACROSS PORTIONS OF EASTERN NEMAHA AND SOUTHWESTERN BROWN COUNTIES.
NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THIS STORM IS
CAPABLE OF PRODUCING PENNY SIZE HAIL AND STRONG WINDS AROUND 50 MPH.
SOME LOCATIONS THAT COULD BE AFFECTED INCLUDE WOODLAWN...WETMORE AND
KICKAPOO RESERVATION.

STAY ALERT TO THE WEATHER IN CASE A WARNING IS ISSUED.

&&

LAT...LON 3993 9595 3975 9561 3965 9572 3965 9579
      3959 9579 3979 9610
TIME...MOT...LOC 1920Z 308DEG 23KT 3984 9600

WOYNICK

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
229 PM CDT SAT SEP 20 2014

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0100 PM     TSTM WND DMG     1 S SENECA              39.82N 96.06W
09/20/2014                   NEMAHA             KS   LAW ENFORCEMENT

            LAW ENFORCEMENT REPORTED AT LEAST 1 POWER POLES BROKEN
            WITH SEVERAL LEANING OVER DUE TO THUNDERSTORM WIND
            DAMAGE.

&&

BDRAKE

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
427 PM CDT SAT SEP 20 2014

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0421 PM     TSTM WND DMG     4 S WAMEGO              39.14N 96.31W
09/20/2014                   WABAUNSEE          KS   LAW ENFORCEMENT

            OLD TREE BLOWN DOWN THAT WAS 12 INCHES IN DIAMETER.
            APPEARED TO BE ROTTED TREE. ALSO PEA SIZE HAIL WAS
            REPORTED WITH THIS ACTIVITY.

&&

BDRAKE

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TOPEKA KS
435 PM CDT SAT SEP 20 2014

KSZ022-023-036-038-202200-
GEARY-POTTAWATOMIE-RILEY-WABAUNSEE-
435 PM CDT SAT SEP 20 2014

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN RILEY...SOUTH
CENTRAL POTTAWATOMIE...EAST CENTRAL GEARY AND NORTHWESTERN WABAUNSEE
COUNTIES...

THROUGH 500 PM CDT...A STRONG THUNDERSTORM WILL MOVE SOUTHEAST AT 20
MPH ACROSS PORTIONS OF SOUTHEASTERN RILEY...SOUTH CENTRAL
POTTAWATOMIE...EAST CENTRAL GEARY AND NORTHWESTERN WABAUNSEE
COUNTIES. NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED THIS STORM
IS CAPABLE OF PRODUCING PENNY SIZE HAIL AND STRONG WINDS OF 40 TO 50
MPH. SOME LOCATIONS THAT COULD BE AFFECTED INCLUDE ST. GEORGE AND
RURAL AREAS OF NORTHEAST GEARY AND WABAUNSEE COUNTIES.

MOTORISTS ALONG INTERSTATE 70 BETWEEN MILE MARKERS 310 AND 321 COULD
ALSO BE AFFECTED.

&&

LAT...LON 3911 9629 3895 9660 3919 9666 3924 9649
TIME...MOT...LOC 2135Z 315DEG 19KT 3917 9653