163
FXUS63 KTOP 171951
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
251 PM CDT Sun Aug 17 2025

.KEY MESSAGES...



- Widely scattered showers and t-storms will be possible mainly
  after midnight into Monday morning.

- Hot weather will persist Monday along with more clouds and
  low chances for t-storms in the morning.

- Higher rain chances should arrive Monday night into Tuesday
  associated with a cold front.

-Expect cooler and drier weather to end the week.


&&

.DISCUSSION...
Issued at 242 PM CDT Sun Aug 17 2025

Early this afternoon an upper level ridge was centered across north
TX, with a ridge axis extending northeast across the mid MS River
Valley. An upper level trough was moving onshore across the Pacific
northwest.

The 18Z surface map showed a lee surface trough across the central
high Plains. A surface warm front was lifting northward across
northern SD into ND and western MN. Most areas were reporting
temperatures in the upper 80s to lower 90s. Heat indices were in
the upper 90s to around 101.


Tonight through Monday:

A weak mid-level perturbation will round the H5 ridge axis Tonight
across NE and central IA. There may be a low chance for showers and
elevated thunderstorms across the northern counties of the CWA
through the early morning hours of Monday as weak ascent ahead
of the h5 perturbation and isentropic lift due to a 30 KT
southwesterly LLJ. The CAMs all have differing solutions on
coverage of the elevated showers and storms. The 17Z run of the
HRRR shows more widespread showers and elevated storms moving
east across the CWA during the early morning hours of Monday.
However, most of the other CAMs only show isolated to widely
scattered showers and elevated storms across portions of north
central and northeast KS. The showers and storms should
dissipate through the mid morning hours.

Monday afternoon will be hot and humid with highs in the lower to
mid 90s. There may be slightly deeper mixing, so heat indices only
reach the upper 90s to around 103 degrees. A heat advisory probably
will not needed Monday afternoon.

Monday night through Wednesday:

The H5 ridge will amplify across the Four Corners region, the
upper flow will be weak but will veer to the northwest. A surface
front across central NE will shift southward across the CWA Tuesday
afternoon. Even though there will not be much upper level support
for ascent, surface convergence and weak mid-level perturbations
within the northwest-northerly upper flow may provide enough ascent
for an area of showers and thunderstorms to develop along the
surface front across north central and northwest KS. This line may
become more widespread as it shifts south across the remainder of the
CWA. The storms may redevelop farther southwest along the better
instability axis across south central KS and northwest OK. The
vertical windshear looks rather weak but a few pulse storms during
the afternoon hours may produce gusty winds at times, along
with brief heavy rainfall.

The lingering showers will shift south of the CWA during the mid
morning hours of Wednesday and skies should clear from
northeast to southwest across the CWA.

Highs on Tuesday will be in the upper 80s to around
90 degrees along the NE border. Highs will be in the lower to
mid 90s across the southern counties ahead of the surface front.
Highs will be cooler on Wednesday with lower 80s along the NE
border and mid to upper 80s across the remainder of the CWA.

Wednesday night through Friday:

The upper ridge will remain anchored across the Four Corners
region with a ridge axis extending northeast across NE into IA.
Expect cooler, less humid and drier conditions. Highs will be
in the 80s.

Friday night through Saturday:

A more amplified H5 trough will round the ridge axis and dig
southeast across the upper Midwest and Great Lakes states. This will
cause our upper flow to back more to the northwest. Mid-level
perturbations embedded withing the stronger northwest mid-level flow
may provide chances for showers and thunderstorms. Highs will remain
in the 80s.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1231 PM CDT Sun Aug 17 2025

Expect VFR conditions for the next 24 hours. Southerly winds may
gust to 18 to 22 KTS this afternoon but diminish towards
sunset. There may be a few CU with bases of 4000 to 6000 feet.

&&

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

&&

$$

DISCUSSION...Gargan
AVIATION...Gargan