798
FXUS63 KTOP 230525
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1225 AM CDT Thu May 23 2024

.KEY MESSAGES...

- Unsettled pattern continues for a few more days.

- Severe thunderstorm chances Thursday into Thursday night, and
  again Saturday into Saturday night.

- Cooler and quieter pattern builds in for the beginning of next
week.

&&

.DISCUSSION...
Issued at 236 PM CDT Wed May 22 2024

A broad longwave trough remains in place this afternoon across the
western 2/3 of the CONUS. One shortwave trough is lifting northeast
across the Great lakes, while the next is digging southeast across
the Pacific Northwest. In between, we have a brief break in the
action as shortwave ridging and surface high pressure are in place
across the central Plains. Yesterday`s cold front has pushed
southward into Arkansas and Texas, leaving behind cooler and drier
conditions for northeast Kansas today. Clear skies and light winds
will be present tonight, creating some minor potential for fog
towards sunrise. Moisture seems marginal enough that this should
stay very patchy, and mostly confined to east-central Kansas in
favored low-lying areas. Regardless, any fog should dissipate
quickly tomorrow morning as winds pick up from the southeast ahead
of the next system.

As that system approaches tomorrow, the warm front will quickly
surge back north while a dryline becomes established across central
Kansas. A cold front then approaches overnight as the main surface
low tracks to our north. A few storms may (20-40% chance) develop
during the late afternoon to mid evening hours, either along the
warm front in northeast Kansas or along the dryline in central
Kansas. Given around 30-40 kts of shear and 2000-3000 J/kg of
MLCAPE, these would be capable of producing large hail and damaging
winds, with a lower chance for a brief tornado. However with large
scale forcing holding off until overnight, there remains uncertainty
with the coverage of any daytime convection. The better chance for
storms looks to be overnight with a line of storms that develops
across Nebraska along the cold front. These storms would move
southeast into north-central and northeast Kansas after midnight.
Depending on the strength of the convective line and its internal
cold pool dynamics, damaging winds would be possible especially
initially. With time and eastern extent though, increasing CIN would
result in a gradual weakening trend.

The pattern repeats for Friday and Saturday. Lingering showers and
clouds clear out Friday morning behind the front, leaving behind a
quiet and sunny afternoon. Highs reach the mid/upper 70s. The next
upper trough approaches for Saturday, resulting in deepening surface
pressure across the central High Plains. This will once again lift a
warm front north across the area as a dryline becomes established
across central Kansas. There is still some uncertainty with exactly
how far north the warm front lifts by the evening, but along and
south of the warm front there will be sufficient instability and
shear for severe weather. Further details will become more clear
over the next few days. By Sunday, the main cold front will be east
of the area. This will limit the severe weather risk, though with
cold temperatures aloft a few thunderstorms with perhaps some hail
will attempt to linger in the area. Beyond Sunday, the upper low
becomes situated over the eastern CONUS, putting our area underneath
northwest flow aloft. This will tend to bring temperatures near or
below average, along with lower (though still non-zero) rain
chances.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1225 AM CDT Thu May 23 2024

VFR conditions expected. Low chance for shallow fog at KTOP near
sunrise, but elevated winds just off the surface should preclude
development. Winds increase from the south-southeast with gusts
around 20kts through the afternoon. Chances for storms during
the late afternoon and evening Thursday are too low for inclusion.

&&

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

&&

$$

DISCUSSION...Reese
AVIATION...Flanagan