Severe Thunderstorm Warning 108, NWS Topeka, KS

Area Forecast Discussion
National Weather Service Topeka KS
637 PM CDT Mon May 27 2019

...Update to aviation forecast discussion...

.SHORT TERM...(This evening through Tuesday)
Issued at 357 PM CDT Mon May 27 2019

Much of the area has broken out into partly cloudy skies this
afternoon, as the system that brought storms overnight moves north
and east of the state. Have had a few echoes on what is likely
the edge of the capping inversion but have not held together with
any success. Surface pressure fields depict a surface low moving
into the upper midwest with cooler air wrapping southward behind.
An inverted trof extends across northeast Kansas, with south
southwesterly winds established south of the boundary. This
boundary provides the focus for possibly some isolated convection
this afternoon, before the LLJ increases in the overnight hours
and develops thunderstorms along and north of the front.

The devil is in the details, with the GFS farther southward with
this boundary than some of the shorter term models, and the
outflow from this convection will likely impact how storms develop
again on Tuesday. Also having an impact will be the potential MCS
that is forecast to move across southern Nebraska overnight into
Tuesday morning, which may also push the boundary farther south
into our area. If this leaves behind a cold pool and enhanced
cloud cover, it would have an impact on how fast and how far south
the atmosphere can recover. The farther south location also puts
down considerably more QPF over the Tuttle Creek basin of an inch
plus. It could also set up a boundary and a triple point over the
middle of the forecast area to enhance what convection does
develop on Tuesday afternoon. It's possible that the low level
wind fields would be enough as the upper trof approaches to lift
the front right back to the north. End result is will need to
watch the mesoscale development for impacts on tomorrows storms.
At this time, plenty of instability in the warm sector and bulk
shear of 30-40 kts, and despite a weak inflection in the middle of
the hodograph, there is enough SRH in the lowest 3K to make all
modes of severe weather possible, with wind and hail more
favorable. As the front sweeps east in the evening and overnight,
rain chances move east as well for the time being and leave
overnight lows in the 50s.

.LONG TERM...(Tuesday night through Monday)
Issued at 357 PM CDT Mon May 27 2019

For Wednesday and Wednesday night, the GFS has trended slower in
pushing the Pacific front all the way through the forecast area,
leaving some instability across east central KS during the afternoon
and evening. And while the NAM has the front through the forecast
area, it is not so far southeast of Anderson county to discount the
GFS. And the model consensus is for another low amplitude shortwave
to lift northeast over the boundary. So have kept some chance POPs
in the forecast across east central KS for the afternoon and
evening. There are mixed signals from the models as to the quality
of shear Wednesday afternoon. So there is some uncertainty in
whether organized severe storms could impact east central KS.
Certainly the instability on the warm side of the front would be
enough to support some severe potential. Will need to watch and see
where it sets up Wednesday afternoon.

For Thursday and Friday, weak surface ridging is expected to move
over the forecast area reducing the moisture and instability. This
in turn is expected to limit chances for rain to less than 20
percent. The GFS and ECMWF do show an upper level shear axis over
northern KS as a cut off low gets reabsorbed into the mean flow. So
the chances for rain may not be zero as the GFS hints at. With the
surface ridging, a slight cool down is expected with highs in the
mid and upper 70s while lows fall into the 50s.

For Saturday through Monday, the models have the moisture and
instability returning north as the synoptic pattern amplifies into
an upper ridge. With weak perturbations rounding the ridge could be
some potential for scattered showers and thunderstorms. Model skill
in the small scale details is not that great so confidence in rain
chances for any one period is marginal. The overall pattern would
support chance POPs just about each day so have not strayed to far
from the model consensus. Highs are expected to be around 80 with
lows around 60 for the weekend and into next week.

&&

.AVIATION...(For the 00Z TAFS through 00Z Tuesday evening)
Issued at 628 PM CDT Mon May 27 2019

VFR conditions are expected through much of the overnight hours.
LLWS conditions are expected after 06Z as a 30-35 kt LLJ near 1.5
kft overspreads the area. LLWS conditions should subside as
boundary layer mixing begins near 13Z and winds increase to 10-15
kt, gusting 20-25 kt by 15Z. In addition, MVFR stratus is expected
to overspread the terminals by 15Z. Scattered thunderstorms are
expected to develop after 19Z, continuing through the end of the
TAF period.

&&

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

SHORT TERM...67
LONG TERM...Wolters
AVIATION...Baerg

Hazardous Weather Outlook
National Weather Service Topeka KS
414 PM CDT Mon May 27 2019

KSZ008>012-020>024-026-034>040-054>056-058-059-282115-
Republic-Washington-Marshall-Nemaha-Brown-Cloud-Clay-Riley-
Pottawatomie-Jackson-Jefferson-Ottawa-Dickinson-Geary-Morris-
Wabaunsee-Shawnee-Douglas-Lyon-Osage-Franklin-Coffey-Anderson-
414 PM CDT Mon May 27 2019

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

.DAY ONE...Tonight.

Thunderstorms are possible tonight across north central and
northeast Kansas. Some of these storms could produce severe
weather with large hail and damaging wind gusts. Areas north of a
line from Concordia to Holton have a better chance to see storms
tonight.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday.

Severe thunderstorms are possible Tuesday afternoon and evening.
These storms could develop across central and north central KS
moving east across northeast and east central Kansas. These
thunderstorms could be capable of producing tornadoes as well as
large hail. Heavy rain with the storms could also renew flash
flooding.

Flooding on area rivers is likely to persist through the middle
of the week.

.SPOTTER INFORMATION STATEMENT...

Spotters should not be needed tonight.

&&

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

Wolters

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE TOPEKA KS
824 PM CDT MON MAY 27 2019

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

0152 AM     TSTM WND DMG     4 W ABILENE             38.91N 97.28W
05/27/2019                   DICKINSON          KS   EMERGENCY MNGR

            DELAYED REPORT...A 3 FEET DIAMETER
            COTTONWOOD TREE WAS UPROOTED AND A 1 FOOT
            DIAMETER TREE WAS SNAPPED 8 FEET ABOVE THE
            GROUND. EMERGENCY MANAGER ESTIMATED 80 MPH
            WIND GUSTS.

&&

BAERG