627
FXUS63 KTOP 212339
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
639 PM CDT Mon Jul 21 2025

.KEY MESSAGES...

- Increasing potential for heavy rainfall and a few strong to severe
storms across north-central Kansas through the evening.

- Storms and clouds add to increased uncertainty for heat today, but
still expecting heat indices 100-108 where things clear out across
souther/western counties.

- Heat indices lower slightly for Thursday and Friday but remain
  hot. Higher confidence in heat increasing again for the
  weekend.

&&

.DISCUSSION...
Issued at 228 PM CDT Mon Jul 21 2025

Continued isentropic ascent amidst deep moisture (12z TOP sounding
had PWAT of 2.19", near record values) has once again allowed
morning storms to fester well into the afternoon. One area of storms
across east-central Kansas storms has mostly weakened, but has left
an outflow boundary stretching back to the northwest over north-
central Kansas. A second area of storms is located in a line from
northeast KS into southern NE along a 850 mb boundary. Farther to
the west, a remnant MCV is moving across northern KS towards our
north-central KS counties. All these features are leading towards a
low-confidence but potentially impactful scenario this evening. As
the MCV approaches over the next few hours, we should see additional
convection blossom. Shear and instability are enough for a few
strong to severe storms, with damaging wind being the main severe
hazard. However the bigger overall hazard should be heavy rain and
localized flooding, given the extremely high moisture availability,
slow storm motion, and convergence associated with the MCV and
surface boundaries. There is still uncertainty on exactly where the
heaviest rain will fall. Convection allowing models have not handled
the setup very well at all the past couple days. But given the
ingredients, and potential for 2-4" with localized flooding with any
higher amounts, decided to go with a Flood Watch for the northern
tier of counties. Heavy rain potential decreases later into the
night as the MCV exits off to the east. Could still see a few
showers and storms linger overnight, and even into tomorrow morning,
as modest isentropic ascent continues. Guidance depicts little
precipitation by this point, but tough to trust that given the past
couple days.

Heat remains the main storyline through the rest of the week, though
the low confidence in convection today into tomorrow does lead to
some uncertainty in exact heat index values. We`ll likely stay well
below previous forecasts today across eastern Kansas where outflow
is keeping current temperatures in the 70s. Tomorrow, most areas
along/south of I-70 will see heat indices around 105. Areas north of
I-70 would see this as well if the clouds are able to clear out by
mid-day, but confidence is lower here. The slightly drier air
Wednesday will likely keep dewpoints a bit cooler, but temperatures
a bit warmer, so heat indices again look to be around 105. Thursday
into Friday, a weak southern stream shortwave will move a weak front
across the area. Cooler mid-level temperatures and more chances for
rain/clouds look to keep temperatures and heat indices slightly
cooler. So may be able to get rid of the heat warning for a couple
days. However the heat should return for the weekend and early next
week as upper ridging expands and becomes centered over Kansas. This
is a better setup for higher confidence heat than the past few days,
when upper ridging was weaker and centered south of the area.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 632 PM CDT Mon Jul 21 2025

In the short-term through about 02-03Z, there could be showers
develop along or behind the outflow from storms north of the
terminals. Also, expect a weak but noticeable wind shift with
the outflow winds which begin the period at KMHK. Winds tend to
veer back to the ESE into the overnight period and then become
more southerly into the day tomorrow with gusty winds into the
late morning and afternoon.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 9 PM CDT this evening for KSZ008-KSZ009-
KSZ020.
Flood Watch until 10 PM CDT this evening for KSZ008-KSZ009-
KSZ010-KSZ011-KSZ012.
Extreme Heat Warning until 7 PM CDT Wednesday for KSZ021-
KSZ022-KSZ023-KSZ026-KSZ034-KSZ035-KSZ036-KSZ037-KSZ038-KSZ039-
KSZ040-KSZ054-KSZ055-KSZ056-KSZ058-KSZ059.

&&

$$

DISCUSSION...Reese
AVIATION...Drake