Special Weather Statement, NWS Topeka, KS

Area Forecast Discussion
National Weather Service Topeka KS
424 AM CDT Thu Jun 29 2017

.SHORT TERM...(Today and tonight)
Issued at 422 AM CDT Thu Jun 29 2017

A complicated set up is in place at 08Z with overnight convection
along the KS/NE border in association with LLJ convergence
continuing to evolve into a more linear small scale MCS advancing
into the richer elevated theta-e axis.  Severe threat at this time
is low with a stable low level boundary layer and the LLJ beginning
to show some signs of weakening on VAD wind profiles. With that
said, some stronger winds may occur with some cells if strong
enough precipitation mixes down stronger winds aloft. The upper
pattern remains mainly zonal with embedded waves traversing the
area. Currently, another cluster of storms is forward propagating
into portions of western KS. This cluster of storms is expected to
enter northeastern KS near the 12-15Z time frame. This will
further complicate the mesoscale set up as currently a diffuse
outflow boundary is stretched along the I-70 corridor. The
synoptic boundary appears to be laid through southeastern NE back
through an inverted trough and leeside low over SE CO into SW KS
vicinity.

Into early this morning, expecting ongoing convection to continue
and taper off by mid to late morning over northeast KS as the LLJ
veers and weakens over the area.  Still some stronger updrafts could
persist with marginal shear and steep mid level lapse rates
contributing to pulsing nature.  As convection diminishes and moves
out of the area, clearing should take place with a weak mid level
cap in place.  Most guidance suggests that with strong
destabilization into the afternoon will likely take place as
southerly WAA continues to pool richer gulf moisture along and ahead
of the synoptic boundary.  As and impending shortwave approaches the
region, mid level lapse rates should steepen and put MLCAPE values
in the 3000-4000 J/kg range. A top of this instability, deep layer
shear values range from 35-50kts which suggests there will be
potential for any storms that develop to quickly rotate.  As
discrete cells mature, there is at least some potential for a
tornado threat to be in place early on into a portion of the evening
hours as SRH values should be between 100-150 m2/s2.  Minimizing
this threat is the fact that surface winds probably remain more
southerly to slightly southwesterly.   However, with the complicated
outflow set up from multiple previous storms over the area, there
could be an opportunity for some storms to ingest more favorable
baroclinic vorticity and stretch that into the updrafts.  Something
that will likely be watch carefully.  But, a large hail threat and
strong outflow wind threat still appears most likely outcome. Storms
should transition into a linear complex once again as the evening
progresses and eventually move out of the area.  Heavy rain is
expected also with these storms, so while the flash flood watch has
been passed at this time it won't be entirely out of the question
that one or two flash flood warnings may be needed. Again, this will
likely be highly localized.

.LONG TERM...(Friday through Wednesday)
Issued at 422 AM CDT Thu Jun 29 2017

Friday through Friday night, the upper trough across the central
plains will will shift eastward into the mid MS river valley. The
surface front will push southeast of the CWA after 12Z. The heavier
rain and thunderstorms will move southeast along the front. There
may be a few isolated showers that redevelop under the H5 trough
axis Friday afternoon but these should end by 23Z. Highs will be
cooler in the lower 80s.

Saturday and Saturday night, the upper trough across the eastern
conus will amplify and cause the mid and upper level flow across the
plains to be from the northwest. At the surface a ridge of high
pressure will push southeast across eastern KS into southern MO and
AR. Highs will be in the mid 80s, with dewpoints in the mid to upper
50s.

Sunday through Wednesday, An upper level trough will move east
across the central rockies, then dig southeast and amplify across
the plains. Both he ECMWF and GFS are much slower digging this upper
trough across the eastern plains. Therefore, expect a chance for
showers and thunderstorms from Sunday afternoon through Wednesday
afternoon. I'm sure there will be some breaks in the rain chances
but 4th of July fire works shows may see at least the chance for
scattered showers and thunderstorms. Highs will be in the mid to
upper 80s.

Wednesday night through Thursday. The upper positive tile upper
trough will finally move southeast across the mid and lower MS river
valley. An upper level ridge will build east across the high plains.
Expect temperatures to warm into the lower to mid 90s on Thursday.

&&

.AVIATION...(For the 06Z TAFS through 06Z Thursday night)
Issued at 1154 PM CDT Wed Jun 28 2017

Confidence is not high in specifics of convective chances, but a
few opportunities remain. Will watch latest trends for possible
early VCTS especially at MHK. Still see better chances for TSRA
to enter the area around 12Z, a bit later than before. Seems to be
enough potential with front in the area for VCTS at the last
several hours of the forecast.

&&

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

SHORT TERM...Drake
LONG TERM...Gargan
AVIATION...65

Hazardous Weather Outlook
National Weather Service Topeka KS
421 AM CDT Thu Jun 29 2017

KSZ008>012-020>024-026-034>040-054>056-058-059-300930-
Republic-Washington-Marshall-Nemaha-Brown-Cloud-Clay-Riley-
Pottawatomie-Jackson-Jefferson-Ottawa-Dickinson-Geary-Morris-
Wabaunsee-Shawnee-Douglas-Lyon-Osage-Franklin-Coffey-Anderson-
421 AM CDT Thu Jun 29 2017

This hazardous weather outlook is for east central...north
central and northeast Kansas.

.DAY ONE...Today and Tonight.

There will be a chance for strong to severe storms this morning,
then again late this afternoon and evening. The main hazards will
be large hail and damaging winds. A tornado or two cannot be
ruled out this afternoon and through the early evening hours.
Locally heavy rainfall will also be possible, which could lead to
some localized flash flooding.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday.

The probability for widespread hazardous weather is low.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed through tonight.

&&

More detailed information can be accessed at...
http://www.weather.gov/top/sitrep

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
1057 PM CDT WED JUN 28 2017

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

1050 PM     HAIL             3 N SCANDIA             39.84N 97.78W
06/28/2017  M1.00 INCH       REPUBLIC           KS   TRAINED SPOTTER

&&

WG

Special Weather Statement
National Weather Service Topeka KS
1220 AM CDT THU JUN 29 2017

KSZ008-009-020-021-290545-
Republic-Clay-Cloud-Washington-
1220 AM CDT THU JUN 29 2017

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN REPUBLIC...
SOUTHWESTERN WASHINGTON...NORTHERN CLAY AND NORTHEASTERN CLOUD
COUNTIES UNTIL 1245 AM CDT...

At 1219 AM CDT, Doppler radar was tracking a strong thunderstorm 4
miles southeast of Agenda, moving east at 20 mph.

Nickel size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Clyde, Clifton, Linn, Palmer, Agenda and Vining.

LAT...LON 3954 9750 3973 9750 3979 9703 3950 9702
TIME...MOT...LOC 0519Z 265DEG 19KT 3966 9738

Gargan

Special Weather Statement
National Weather Service Topeka KS
1248 AM CDT THU JUN 29 2017

KSZ021>023-290615-
Clay-Pottawatomie-Riley-
1248 AM CDT THU JUN 29 2017

...SIGNIFICANT WEATHER ADVISORY FOR WEST CENTRAL RILEY...WESTERN
POTTAWATOMIE AND EAST CENTRAL CLAY COUNTIES UNTIL 115 AM CDT...

At 1247 AM CDT, Doppler radar was tracking a strong thunderstorm near
Leonardville, moving east at 35 mph.

Nickel size hail and winds in excess of 30 mph will be possible with
this storm.

Locations impacted include...
Northern Manhattan, Riley, Leonardville, Olsburg, Randolph, Keats and
Tuttle Creek Lake.

LAT...LON 3948 9643 3921 9641 3922 9699 3940 9700
TIME...MOT...LOC 0547Z 266DEG 28KT 3932 9690

BD

Special Weather Statement
National Weather Service Topeka KS
221 AM CDT THU JUN 29 2017

KSZ008-009-290745-
Republic-Washington-
221 AM CDT THU JUN 29 2017

...SIGNIFICANT WEATHER ADVISORY FOR REPUBLIC AND NORTHWESTERN
WASHINGTON COUNTIES UNTIL 245 AM CDT...

At 219 AM CDT, Doppler radar was tracking a cluster of strong
thunderstorm across Republic County which extended west into Jewel
County. These storms were moving east at 35 mph.

Dime to nickel size hail and winds in excess of 40 mph will be
possible with these storm.

Locations impacted include...
Belleville, Washington, Linn, Scandia, Courtland, Cuba, Morrowville,
Republic, Haddam, Munden, Narka, Mahaska and Agenda.

A severe thunderstorm watch remains in effect until 1000 AM CDT for
north central Kansas.

LAT...LON 4000 9701 3968 9703 3973 9793 4000 9793
TIME...MOT...LOC 0719Z 277DEG 31KT 3990 9768

Gargan

Special Weather Statement
National Weather Service Topeka KS
407 AM CDT THU JUN 29 2017

KSZ022-023-038-290930-
Wabaunsee-Pottawatomie-Riley-
407 AM CDT THU JUN 29 2017

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN RILEY...NORTHWESTERN
WABAUNSEE AND SOUTHWESTERN POTTAWATOMIE COUNTIES UNTIL 430 AM CDT...

At 407 AM CDT, Doppler radar was tracking a strong thunderstorm 5
miles northeast of Keats, moving southeast at 35 mph.

Dime size hail and winds in excess of 40 mph will be possible with
this storm.

Locations impacted include...
Manhattan, Wamego, Alma, St. George, McFarland, Keats, Tuttle Creek
Lake and Volland.

This includes Interstate 70 between mile markers 316 and 331.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

A severe thunderstorm watch remains in effect until 1000 AM CDT for
northeastern and east central Kansas.

LAT...LON 3911 9616 3892 9640 3901 9650 3907 9650
      3907 9657 3925 9677 3938 9662
TIME...MOT...LOC 0907Z 312DEG 32KT 3927 9663

BD

Special Weather Statement
National Weather Service Topeka KS
441 AM CDT THU JUN 29 2017

KSZ022>024-036-038-039-054-055-291015-
Wabaunsee-Geary-Shawnee-Lyon-Pottawatomie-Riley-Jackson-Osage-
441 AM CDT THU JUN 29 2017

...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL GEARY...SOUTHEASTERN
RILEY...SHAWNEE...WABAUNSEE...NORTHWESTERN OSAGE...SOUTHEASTERN
POTTAWATOMIE...SOUTHWESTERN JACKSON AND NORTH CENTRAL LYON COUNTIES
UNTIL 515 AM CDT...

At 441 AM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Emmett to 6 miles northwest of Volland.
Movement was southeast at 40 mph.

Dime size hail and winds in excess of 40 mph will be possible with
these storms.

Locations impacted include...
Topeka, Wamego, Rossville, Alma, Eskridge, St. Marys, Dover, Silver
Lake, Auburn, Maple Hill, McFarland, Harveyville, Paxico, Belvue,
Emmett, Allen, Delia, Willard, Bushong and Keene.

This includes the following highways...
 Interstate 70 between mile markers 317 and 355.
 Kansas Turnpike between mile markers 161 and 164, near mile marker
167, and between mile markers 176 and 177.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with these storms, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

A severe thunderstorm watch remains in effect until 1000 AM CDT for
northeastern and east central Kansas.

LAT...LON 3878 9594 3861 9624 3880 9639 3882 9639
      3883 9641 3902 9656 3938 9606 3907 9560
TIME...MOT...LOC 0941Z 318DEG 33KT 3929 9609 3901 9649

BD