345
FXUS63 KTOP 211644
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1144 AM CDT Tue May 21 2024

.KEY MESSAGES...

- There will be a chance for isolated to scattered severe storms
along a cold front moving through the area for a few hours this
afternoon from far northeastern to far east central Kansas areas.
Large hail appears to be the primary hazard with damaging winds
possible before storms move east of the area. The threat for
tornadoes is low.

- Marginally severe storms may be possible again Thursday across the
area as another weather system enters the region. However, details
at this time remain uncertain.

- Off and on rain and storm chances look possible through the
Memorial Day weekend.

&&

.DISCUSSION...
Issued at 353 AM CDT Tue May 21 2024

Early this morning, storms continue across the state of Nebraska and
into Iowa with convection training along the nose of the LLJ which
has started to relax slightly. A couple of line segments also
continue to track into south central Nebraska and portions of
northwestern into north-central Kansas areas. These bear watching as
they may brush along the KS/NE border. Overall, these storms are
likely more elevated than just an hour or so ago as prior outflows
have continued to push through the pre-storm environment which these
line segments area advancing into. As convergence weakens, the
expectation is these storms will continue to also weaken without the
LLJ feeding into them. So, right now, would anticipate severe trends
to continue to subside if they do make it to the local area.

Later this afternoon a compact shortwave now evident over central CO
vicinity will continue to lift into Nebraska and induce a new lee
cyclone off the foothills of the Rockies into the High Plains
region. This will deepen quickly and by this afternoon a modified
cold front quickly moves from west to east across the area. Initial
capping appears to be strong enough to keep convection delayed until
mid afternoon and allowing the front to move across much of the area
without too much impact until it reaches far northeastern and far
eastern Kansas areas. Best forcing with the wave at this time will
be displaced to the northeast of the area. Southern extent of storm
development is somewhat uncertain coverage wise, but expect a short
window this afternoon for storms to quickly develop over eastern
areas. Large hail would be possible with steep lapse rates in place
and sufficient shear. Storm motions should allow for quick moving
storms to exit the area by around 5 pm or so. Then further
development of storms should be focused east of the area for this
evening.

Wednesday looks nearly perfect with lower dewpoints as cooler
modified Canadian air expands into the region.  Into Thursday,
storms may be possible again but details look uncertain at this
time. Semipermanent broad troughing across the western into the
central CONUS allows for a modified Pacific system to dig into the
northern Plains. Again, best forcing for ascent appears displaced
north of the area. Question regarding quality return setup and thus
quality theta-e airmass back into the region remains to be seen.
Right now, marginally severe storms may be possible as another weak
cold front is pushed through the region.

Into the Memorial Day weekend, off and on showers and storms may be
possible as the overall setup remains with a couple of perturbations
poised to enter the area providing a mechanism for lift. Quality of
moisture return for these systems will again be a question.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1144 AM CDT Tue May 21 2024

CAMs have been consistent in developing TS east of TOP and FOE
this afternoon. So will keep a dry forecast. The stratocu deck
will eventually lift above 3 KFT as the boundary layer continues
to warm. There might be some high based showers overnight, but
confidence in coverage is to limited to include in the forecast.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Drake
AVIATION...Wolters