468
FXUS63 KTOP 161652
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1152 AM CDT Thu Oct 16 2025

.KEY MESSAGES...

- A frontal boundary moves into the area Friday into Saturday
  morning with chances for showers and storms between 30-80%.

- There is a marginal risk for severe storms Friday afternoon
  across parts of northeast and east central Kansas, then Friday
  night for areas of east central KS, southeast of the KS
  turnpike.

- Temperatures will remain warm to end this week. But
  Occasional cold fronts are expected to bring cooler temps
  through next week.

&&

.DISCUSSION...
Issued at 332 AM CDT Thu Oct 16 2025

Early this morning, water vapor satellite imagery showed a deep upper
low centered over southern UT, with a trough axis extending south-
southwest across the CA/AZ border, then southwest across the Baja
Peninsula of Mexico. A down stream upper level ridge was
centered over southern AR with a ridge axis extending northward
across western MO into central IA and central MN. An upper
trough was located across New England, southward across the Mid
Atlantic States.

The 7Z surface map showed a lee surface trough across the central
and southern high Plains. A surface low was located across the
southern NE PNHDL, with a warm front extending northeast across
southeast ND into northern MN. The richer gulf moisture was located
across far south TX with dewpoints in the mid to upper 60s.


Today through Tonight:

The upper low across southern UT will lift northeast into the
northern Plains late Tonight. As the upper low lifts northeast
across the central Rockies it will fill a bit and shear off from the
southern stream upper trough across CO, extending southwest
across eastern AZ. The stronger southwesterly mid level flow
over the Rockies will deepen the lee trough across the central
and southern high Plains. Southerly winds across the CWA will
increase this afternoon to 15 to 25 MPH with gusts of 25 to 35
MPH, the stronger wind gusts will be across north central and
central KS. High and some mid clouds will increase through the
day and into Tonight. A cold front will move southeast across
western NE and northern CO, into western KS by 12Z. There may be
some weak isentropic lift developing as modified moisture over
OK advects northward across central and north central KS. The
isentropic lift may cause a few showers and elevated
thunderstorms to develop across north central KS during the
early morning hours of Friday.

Highs today will be warm once again into the lower to mid 80s.

Friday through Saturday:

The positive tilt H5 trough across CO and AZ will shift east. Ahead
of the H5 trough axis there will be a southwesterly H5 jet max of 40-
50 KTS shifting east across KS. Several CAMs show elevated showers
and storms moving across the CWA during the morning hours, then we
may see a break during the late morning and early afternoon hours as
the surface Pacific cold front/trough axis pushes east across north
central KS. Most CAMs have the Pacific front moving into northeast
and east central KS by 21Z. Surface convergence ahead of the front
combined with DCVA ahead of the positive tilt H5 trough will provide
enough ascent for scattered thunderstorms to develop along the front
around or just after 21Z.

The HREF ensemble mean for surface based CAPE Friday afternoon
around 22Z ranges from 500 to 800 J/KG, so instability will be
marginal. Also the HRRR forecast sounding do not show very steep
lapse rates in the low and mid levels. Most CAMs have veered
surface winds at the surface ahead of the front, so there may
not be much directional shear. However, effective shear of 20 to
30 KTS may cause an updraft to intensify enough to produce
marginal surface wind gusts and may be some hail of 1 inch, if
the mid level of the updraft exhibit cyclonic rotation. Another
negative will be deeper mixing of the modified moisture during
the late afternoon ahead of the Pacific front. If dewpoints mix
down to the mid 50s, there may be slight inverted V in the lower
levels of the forecast sounding, so this may lead to some gusty
winds around any thunderstorm updraft.

Friday night, the Pacific front/surface trough will undergo
frontolysis and somewhat richer moisture will advect northward
across east central KS. The southern stream H5 trough across
western KS will phase with and amplify as a northern stream H5
trough digs southeast across the Plains. A second stronger front
will push southeast across KS during the night and the
combination of surface convergence ahead of the cold front and
DCVA ahead of the more amplified H5 trough may provide our best
chance for showers and thunderstorms. A few of these storms
across east central KS, generally southeast of the KS turnpike,
could be strong to severe through the night as MUCAPEs may
increase to 1000 J/kg and effective shear increases above 35
KTS. The primary hazard would be large hail if elevated updrafts
exhibit mid-level rotation.

Saturday through Saturday night:

As the H5 trough moves east across KS it will continue to
amplify as it phases with the southern stream H5 trough. The
surface front will move southeast across the CWA during the
morning hours. If the front is a bit slower, then there could be
a chance for thunderstorms developing along the front during
the afternoon hours which could be strong to severe. However
most model guidance show the front shifting southeast of the CWA
by Noon. There may still be some post frontal showers and
elevated thunderstorms across east central KS into Saturday
afternoon but the severe weather threat will remain across
southeast KS, eastern OK, AR, and southern MO Saturday afternoon
and evening.

The amplified H5 trough axis will shift east into MO Saturday night
and the stronger ascent will be across the MS River Valley. This
should bring an end to any showers or elevated thunderstorms.

Sunday through Sunday night:

Expect cooler temperatures on Sunday as the mid level flow
across the Plains will be from the northwest. A surface ridge of
high pressure will build southeast across the central and
southern Plains. The low-level CAA will keep highs in the 60s.
Lows Sunday night will be in the upper 40s to lower 50s.


Monday through Thursday:

The longer range models are in general agreement with the main
northern H5 jet shifting farther south across the central Plains. An
upper trough will move east across the Plains Monday night, which
may bring a chance for a few showers. The richer moisture will be
trapped farther south across TX, so with only modified moisture, I
don`t expect much QPF with this system. Ahead of the H5 trough
southerly winds on Monday will help to warm high temperatures back
into the mid to upper 70s.

Monday night into Tuesday morning a cold front will shift
southeast across the CWA. This should bring an end to any light
rainshowers that may develop ahead of the H5 trough. Highs on
Tuesday will be cooler back into the 60s.

An H5 trough will amplify across the east central US. This will keep
the central Plains in northwest flow aloft. Expect dry
conditions and temperatures will be closer to seasonal norms
with highs int he mid to upper 60s Wednesday and Thursday
afternoon.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1152 AM CDT Thu Oct 16 2025

Weak isentropic lift is progged to develop within a narrow
section of warm air advection late tonight. This may lead to
some isolated showers by Friday morning. The forcing overall
appears to be relatively weak and CAMs suggests probabilities at
the terminals are generally less than 20 percent. So will not
include a mention of precip in the TAFs at this time. There is
some potential for LLWS as a 35KT to 40KT low level jet develops
overnight. Forecast soundings do not show a lot of directional
shear and a strengthening pressure gradient may keep some mixing
in the boundary layer. So LLWS will be dependent on whether the
boundary layer decouples. Will late later shifts monitor trends
and decide whether wind shear is appropriate for the forecast.

&&

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

&&

$$

DISCUSSION...Gargan
AVIATION...Wolters