824
FXUS63 KTOP 261730
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1230 PM CDT Thu Jun 26 2025

.KEY MESSAGES...

- A line of storms is expected to develop along a cold front by
  mid to late this afternoon and slowly push southeasterly
  through the area. Could see a few instances of damaging wind
  with early storms and as well as hail possibly around quarter
  size. Heavy rain also looks possible with this setup as storms
  congeal and generally move slowly.

- Hot and humid through the weekend with temperatures 90s and
  heat index values around 100 before cooling back to the 80s
  by Monday behind a cold front on Sunday.

- Sunday`s cold front should bring more widespread storm chances
  to the area with a stronger push of energy associated with the
  overall system. Have a 60-70% chance for precipitation Sunday
  night into early Monday morning right now.

&&

.DISCUSSION...
Issued at 311 AM CDT Thu Jun 26 2025

The upper ridge east of the region continues to flatten with the
western flank seeing subtropical moist air streaming into north into
the central and northern Plains. A Pacific trough is entering the
northwestern CONUS at this time which appears to be the primary
feature of interest for Sunday`s storm system. A weak frontal
boundary is in place from northeastern Nebraska down into western OK
and the panhandle region of TX at this hour with a broad area of
precipitation ongoing just west of the forecast area from north-
central KS into central and northeastern Nebraska.

This front slowly pushes into the area today. A weak capping
inversion should be in place through the morning and early into the
afternoon across the area today. With a high PW airmass in place and
dewpoints around 70 degrees, plenty of moisture will remain in place
very typical of this time of year. The mean Westerlies reside well
north of the region leading to a low shear high instability
environment in place for today. As insulation destabilizes the BL,
expect any cap to erode this afternoon which should help storms
develop along the boundary. Most CAMs suggest a mid to late
afternoon initiation, but this could happen sooner if localized
updrafts break weaker areas of the cap sooner. With the overall
instability, would expect that storms develop quickly and with
little shear in place and generally slow storm motions, any cold
pool outflows develop subsequent storms and the threat could quickly
shift to localized flooding concerns despite flash flood guidance
ranging in the 2-3 inch category. There is a enough uncertainty in
coverage overall that a flood watch has not been issued but not
ruling out localized flood concerns mainly due to slow motions and
possible redevelopment on outflow boundaries as previous storms
collapse typical of the multi-cellular regime anticipated. Initial
storms would likely be the damaging wind producers and could produce
some hail as well.

With little airmass change behind today`s frontal boundary, expect
hot and humid air to remain in place through the weekend ahead of
the aforementioned Pacific system. Temperatures through Sunday
remain in the 90s with heat index values around 100 degrees much of
that time as well.

Sunday evening into the overnight period, a more significant Pacific
frontal system pushes into the region in association with a digging
upper trough across the northern into central Plains. Expect the
southern flank of the trough may reach this far south but should
still realized better overall shear which may increase the organized
storm threat along a strong frontal boundary. A cooler airmass
arrives into Monday and the balance of next week is looking to feel
cooler overall leading into July 4th weekend.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1229 PM CDT Thu Jun 26 2025

Confidence is low on the exact timing and coverage of
scattered thunderstorms that will develop this afternoon and
evening, so have just left a Prob30 group at the main TAF sites. Any
storms should move east of KTOP/KFOE by mid to late evening though.
Ceilings remain VFR, with this afternoon`s gustier south winds
weakening this evening.

&&

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

&&

$$

DISCUSSION...Drake
AVIATION...Reese