639
FXUS63 KTOP 051139
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
639 AM CDT Wed Aug 5 2026

.KEY MESSAGES...

- Unsettled weather with chances for showers and storms remain in the
  forecast through Friday morning.

- Hot and dry weather is expected to return this weekend and early
  next week.

&&

.DISCUSSION...
Issued at 248 AM CDT Wed Aug 5 2026

Early this morning, water vapor satellite imagery and upper air
analysis showed a broad upper level trough across the northern
Plains, with the trough axis extending southward to the KS border. A
broad upper level ridge extended from southern CA, east into west
TX. A cutoff low was located across the southeast US.

The 6Z surface map showed a cold front extending from eastern IA,
southwest across northwest MO, southwest across east central KS (from
west of LWC, to west of EMP). The front then extended southwest into
northwest OK, then west across the northern TX PNHDL. Behind the
front across the northern and western counties of the CWA,
temperatures were in the mid 60s. Ahead of the front across portions
of east central KS, the temperatures were in the mid 70s.

Today through Tonight:

The southern extent of the northern Plains H5 trough will shift
east-southeast across KS this afternoon. Most CAMs show the surface
front across east central KS, shifting south of the CWA by this
afternoon. A lead perturbation within the H5 trough will be lifting
northeast across IA. The only CAM that shows higher QPF is the Nam12.
Most others only show isolated showers through the day north of the
front. Highs this afternoon will only reach the mid 70s across the
northern counties of the CWA. Farther south, closer to the front,
highs will reach the lower to mid 80s across the southeast counties.

Tonight, the LLJ will increase from the southwest up to 30 KTS. The
resulting isentropic lift will provide enough ascent for scattered
to numerous elevated thunderstorms to develop, with the higher Pops
around 60 percent across the east central KS. A few of the storms
could be strong given steep mid-level lapse rates, close to 1000
J/KG of MUCAPE, and 30 KTS of effective shear. The primary hazard
from any strong storms will be small hail and brief heavy rainfall.

Thursday through Friday:

The broad H5 trough will move east into the upper Midwest and mid MS
River Valley on Thursday. The surface front will move southward and
become stationary across northern OK. A mid-level perturbation will
dig southeast from the northern High Plains across NE and KS, while
a southerly LLJ will increase to 30 KTS. The LLJ jet will cause
isentropic lift, and combined with ascent ahead of the H5 trough
will cause showers and elevated thunderstorms to develop Thursday
evening into early Friday morning. NBM PoPs are over 80s percent
across the central and east central counties of the CWA from 6Z-12Z
Fri.The LREF forecast over a 50 percent chance that east central KS
will receive 0.25" or more of QPF Thursday night through Friday
morning. The surface front will lift north into NE by Friday evening.
The H5 ridge across the southwest US will build east across central
High Plains into southern KS and northern OK. This should keep any
mid-level perturbations digging southeast to the north and east of
the CWA, so the rain chances will drop during the afternoon hours of
Friday.

Highs on Thursday will reach the lower 80s north to mid and upper
80s south, with more insolation during the afternoon hours.

Friday night through Monday:

The extended range models are in good agreement with the southwest
US H5 ridge axis expanding east into the southern and central Plains
by early next week. Highs will warm into the upper 80s to mid 90s on
Saturday, with lower to mid 90s Sunday and Monday. Southerly surface
winds will advect richer moisture northward Sunday and Monday, thus
afternoon dewpoints across east central KS may not mix out much, with
dewpoints in the lower 70s. Therefore, afternoon heat indices may
reach the 100-105 degree level across east central KS for Sunday and
Monday afternoon.

Monday night through Wednesday:

The GFS and Canadian models forecast the H5 ridge to retrograde
westward into NM/west TX. The ECMWF model forecast the H5 ridge to
remain in the region with a slight shift southward of the center of
the H5 ridge axis into TX. If the GFS and Canadian models turn out
to be correct, the mid level flow will become northwesterly and
there may be a chance for showers and thunderstorms ahead of any
embedded perturbation in the northwest flow aloft. The ECMWF looks to
be drier and a bit hotter with high only retreating slightly into
the lower to mid 90s.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 635 AM CDT Wed Aug 5 2026

The thunderstorms should remain south of the terminals this morning.
There may be occasional showers through the day. MHK has had LIFR
ceilings all night. The low ceilings are west of KTOP and KMHK. The
RAP model seems to have the best handle on the ceiling forecast.
After 16Z the MVFR stratus ceiling should move into the KTOP and
KFOE terminals. There is a chance they may go down to IFR during the
late morning and early afternoon hours. KMHK may rise to 1100 feet by
afternoon. The MVFR ceilings will remain in place during the night.
After 6Z there will be scattered thunderstorms through the early
morning hours at KTOP and KFOE. The thunderstorms may remain just
east of KMHK.

&&

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

&&

$$

DISCUSSION...Gargan
AVIATION...Gargan