351
FXUS63 KTOP 161741
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1241 PM CDT Wed Apr 16 2025

.KEY MESSAGES...

- Scattered elevated thunderstorms likely (70%) tonight. A few of
the storms could produce large hail.

- Record warm temperatures Thursday. Breezy and very dry conditions
will also lead to very high fire danger over central KS.

- Shower and thunderstorm chances return Friday PM and into the
  weekend.

&&

.DISCUSSION...
Issued at 408 AM CDT Wed Apr 16 2025

Water vapor imagery this morning shows upper ridging shifting
eastward across the Plains, with deep upper troughs over both
coasts. The West Coast upper trough is made up of two distinct
pieces - one temporarily cutoff low off southern California and one
more vigorous shortwave diving southeast over the Pac-Northwest. As
this trough deepens today, WAA and isentropic ascent will gradually
increase over the Central Plains. This will lead to several chances
for showers and storms to develop. The first will come late this
morning across east-central KS on the leading edge of isentropic
ascent. Instability will be quite weak at this point, and lots of
dry air will be present. So expecting coverage of any showers/weak
thunderstorms to be quite low. The second and most-widespread chance
for storms will be overnight tonight as the LLJ strengthens and 1000-
1500 J/kg of MUCAPE develops. Stronger isentropic ascent should make
for more widespread though still scattered thunderstorms, though the
exact area of development remains uncertain. With very steep mid-
level lapse rates and 20-30 kts of effective shear (given a storm
base around 700 mb), large hail to around 1.5" seems the most likely
hazard.

Any storms should quickly move off to the east by around sunrise
Thursday as warmer and drier mid-level air arrives. Deep mixing of
these warm mid-level temperatures (~20 C at 850 mb) will make way
for a very warm afternoon. Temperatures are likely (60-70%) to
exceed daily record values, with an outside shot (10%) at reaching
the monthly record high for April. Coupled with breezy southwest
winds, the very warm temperatures will also result in elevated fire
danger. This will particularly be the case across the western half
of the area, where dewpoints and RH will be lower behind a dryline.
See Climate and Fire Weather sections for more info on Thursday.

Thursday night, the northern portion of the western trough will push
a cold front southeastward through the area. Can`t rule out a brief
shower or storm as this occurs, but the warm mid-level temperatures
ahead of the front will tend to suppress any convection. Better
storm chances should stay to our north and northeast as a result. By
Friday afternoon and evening, the front will be mostly through our
area. A slower front could allow for a few storms to develop across
east-central KS, while a faster front would keep storm potential
mainly southeast of Anderson County. By Saturday into Sunday, the
front should stall a bit southeast of the area while the southern
portion of the upper trough lifts northeast towards the area. This
will help more widespread showers and storms develop north of the
front. Exact rainfall amounts are still uncertain, but the potential
for appreciable rainfall is trending upwards across most of the
area. Particularly east-central KS, where the probability of at
least 1" of rain is up to around 30% Saturday night into Sunday.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1238 PM CDT Wed Apr 16 2025

Gusty winds impact TAFs through the afternoon. With this update,
have included prevailing groups for TSRA tonight at all sites
for the period most likely to see storms. Timing may need to be
tweaked slightly as model trends are analyzed or once storms
develop and can be tracked. Otherwise, storms move out and
southerly winds increase again after sunrise Thursday. Gusts to
30 kts will be possible by 18Z Thursday.

&&

.FIRE WEATHER...
Issued at 242 AM CDT Tue Apr 15 2025

Despite vegetation greening up across the area, very high fire
danger is still expected to develop across portions of central
Kansas on Thursday. As low pressure moves northeast across Kansas,
very dry air will move eastward behind a dryline. There is some
east/west uncertainty in how far east the dry air will reach, but RH
in the 10-20 percent range is likely. Southwest winds Thursday
afternoon and early evening look to be sustained 15-20 mph, with
gusts to around 30-35 mph. A cold front then moves in from the
northwest overnight Thursday. This will switch winds to the
northwest at 10-15 mph sustained, but also quickly bring in higher
RH from the north.

&&

.CLIMATE...
Issued at 414 AM CDT Wed Apr 16 2025

              April 17 Daily Record       Forecast
Topeka                  90 (1954)           91
Concordia               90 (1926)           92

              April Monthly Record
Topeka        97 on April 6, 1893 and April 25, 2012
Concordia     100 on April 20, 1902

&&

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

&&

$$

DISCUSSION...Reese
AVIATION...Teefey
FIRE WEATHER...Reese
CLIMATE...Reese