879
FXUS63 KTOP 110855
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
355 AM CDT Fri Sep 11 2026

.KEY MESSAGES...

- Areas of fog, potentially dense in some spots, will continue
through early morning across eastern KS.

- Lowered rain chances for tonight into Saturday morning, with
better chances (30-50%) late Saturday afternoon into evening. Can`t
rule out a few strong to severe storms during that time.

- Next best chance for rain (50-80%) comes Monday night into
Tuesday, especially across northern KS.

&&

.DISCUSSION...
Issued at 354 AM CDT Fri Sep 11 2026

Broad cyclonic flow is noted over the northwest portion of the CONUS
with a couple of shortwaves in Canada helping to contribute to that
pattern, while a weaker shortwave can be seen pushing southeast of
the local area, leaving more zonal flow aloft for today. Surface
high pressure is influencing eastern KS, and clear skies and light
winds have allowed us to reach crossover temperatures from yesterday
with fog observed in parts of east central KS. So far fog has been
on the patchy side, though visibility could quickly drop to a half
mile or less in spots, particularly low-lying places and those spots
that saw more rain recently. HREF probs for half mile or less show a
decent signal for dense fog for a few hours around sunrise in
eastern KS. Will continue to monitor obs and webcams to determine
the need for a Dense Fog Advisory this morning if those lower
visibilities indeed become more widespread. Forecast soundings show
fog mixing out around 14z, at which point visibility should improve.

As mentioned previously, the main challenge with the forecast
becomes timing and location of the greatest rain chances. CAMs are
not excited about developing storms along the frontal boundary in
southern Nebraska this evening, the 06z runs even less so than the
00z. Even if something isolated were to develop as 00z runs
indicate, the instability axis is fairly narrow and mainly west of
the area with a less favorable environment further east in terms of
both instability and shear. Would think storms would have a harder
time maintaining themselves into our area with that setup, plus
there isn`t a lot of forcing to support maintenance. The frontal
boundary sags south through the day Saturday and would provide a
better source of lift for thunderstorms. Assuming we don`t have much
in the way of rain or cloud cover into Saturday morning, we would
also have better instability with MLCAPE increasing to 3000-4000
J/kg by late afternoon alongside deep-layer shear around 40 kts.
This could support a few strong or severe storms with damaging wind
and small hail being the main hazards into the evening. Pwat around
2" could lead to brief heavy downpours as well, though widespread
flooding is not anticipated with storms looking to be more
scattered. It is worth noting that recent models seem to be placing
the front further south, which would favor southern portions of the
area during this time frame.

As a deep upper low comes onshore of the Pacific Northwest and the
upper ridge strengthens slightly just to our south, the sfc front
looks to lift back north as a warm front Sunday into Monday. This
leads to southwesterly flow developing aloft and warming
temperatures. While some rain chances linger into Sunday, a general
drying and clearing trend is expected from south to north through
the day. Most of Monday looks dry until the evening hours when
storms develop along the front, which at this time looks to be
placed from southeastern NE through north central KS with the sfc
low located in southwest KS into the OK/TX panhandles. With the
aforementioned upper ridge strengthening over the southeastern US by
Tuesday, this slows the southward movement of the sfc front which
may stall over the region on Tuesday. This keeps likely PoPs over
much of the area during the day. Tuesday onward is also when we
begin to see large spreads in temperatures, which will be tied to
the exact location of the front as well as clouds and rain. The
front may again move back north on Wednesday depending on the
strength of the upper ridge. Uncertainty in the evolution of that
pattern leads to lower confidence in the later part of the forecast
period in terms of precipitation and temperatures, with at least
some rain chances persisting through mid-week.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1232 AM CDT Fri Sep 11 2026

Main focus for this forecast period is fog potential in the near-
term. Maintained timing and categories from previous issuance, as
TOP/FOE are more favored to see vsby drop to IFR or LIFR with lesser
confidence towards MHK. Any fog should mix out to MVFR stratus around
14z with VFR conditions taking over late morning.

&&

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

&&

$$

DISCUSSION...Picha
AVIATION...Picha