979
FXUS63 KTOP 170649
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
149 AM CDT Fri Jul 17 2026

.KEY MESSAGES...

- There could be an isolated shower or storm this afternoon.

- Confidence in a warming trend through the weekend and into Monday
  is good. Some locations could see triple digits for highs Monday.

- A pattern shift by the middle of next week looks to bring about
  more normal temperatures and a chance for showers and storms.

&&

.DISCUSSION...
Issued at 149 AM CDT Fri Jul 17 2026

Water vapor imagery from 07Z showed an upper low over west TX with
an upper ridge axis set up from the central Rockies to the upper MS
river valley. This placed the forecast area under the influence of
the ridging while the mean westerlies remained over the northern and
Canadian plains. Surface obs showed a rather relaxed pattern with low
pressure across the northern plains and high pressure across the
lower MS river valley.

The forecast for the next several days is expected to be influenced
mainly by upper ridging with the model consensus showing the ridge
building across the central high plains through Monday. So the
synoptic pattern looks to favor a warming trend with limit chances
for precip. This afternoon looks to be a period where isolated
storms pop up. Forecast soundings across the region show an uncapped
airmass with modest instability which could be enough for an airmass
shower. But limited wind shear and no obvious dynamics within the
upper ridge should keep any storm that forms of the pulse variety
similar to what we had Thursday. Although CAMs don`t show nearly the
coverage of showers and thunderstorms. The upper ridge strengthening
for Saturday through Monday lower probabilities for precip.

Cluster analysis of the 12Z ensembles shows there is not much
difference from the models through Monday. And the
GFS/ECMWF/Canadian ensembles show pretty reasonable spreads in temps
of three to five degrees through Monday. This lends some confidence
in the NBM temp forecast for Sunday and Monday. Unfortunately the
spreads in dewpoint temps don`t remain as low and the NBM is showing
dewpoints mixing out a little more by Monday. Still there is a
signal for heat indices between 100 and 105 degrees in the afternoon
Sunday and Monday. Some places may see air temps hit 100 degrees
Monday.

By the middle of next week, cluster analysis shows some differences
in the amplitude of the ridge/trough pattern over North America and
introduces more variability and spread in the forecast. However the
general idea is for the upper ridge to begin shifting west and south
by Tuesday. This should bring a better opportunity for perturbations
within the pattern in impact the forecast area and also allow temps
to trend closer to normal. Operational solutions are pointing
towards Wednesday night and Thursday morning for some shortwave
energy to move across the area and bring a chance for showers
and storms. This is reflected in the NBM forecast pretty well.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1207 AM CDT Fri Jul 17 2026

An uncapped airmass is expected again for Friday afternoon with
little forcing or lift. But some of the CAMs are starting to show
isolated SHRA possible. The probability of TSRA at a terminal is
around 20 percent, and with low predictability it`s hard to justify
adding a mention in the forecast at this time. There could be some
patchy ground fog at TOP through sunrise, otherwise VFR conditions
should prevail.

&&

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

&&

$$

DISCUSSION...Wolters
AVIATION...Wolters