175
FXUS63 KTOP 012349
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
649 PM CDT Mon Jul 1 2024

.KEY MESSAGES...

- Heat becomes more widespread Tuesday, with Heat Advisory in effect
mainly south of the Hwy 36 corridor.

- Low chance for storms near the KS/NE border tonight. Greatest risk
for organized severe risk comes Tuesday afternoon/evening, which
could also bring another round of heavy rainfall.

- Periodic chances for storms continue through the 4th of July
  holiday.

&&

.DISCUSSION...
Issued at 256 PM CDT Mon Jul 1 2024

Two areas of sfc low pressure are noted as of 19Z, one centered in
SD and the other near the CO/KS border, both in response to the
upper trough slowly advancing across the western US. Meanwhile the
upper ridge holds steady over the south central CONUS. Cloud cover
has been slow to scatter out, but recent satellite imagery indicates
it should do so more quickly over the next hour or two. Clearing
should still allow temperatures to heat up, but likely not as much
as originally anticipated. Heat indices may still reach triple
digits in parts of north central KS in the few hours left of peak
heating, so will keep the advisory going in those areas today,
though they may fall just short of criteria. The greater heat
concern comes Tuesday as low-level moisture builds in and WAA
commences overnight into tomorrow. A cold front approaching from NE
by midday should help keep temperatures around 90 for counties along
the KS/NE border, while most areas south should see deep enough
mixing with warm 850mb temps to bring highs to the mid 90s to around
100. Have kept Tuesday`s advisory as is.

Regarding storm chances through the next 24-36 hours, there remains
a low chance for a few showers or storms to clip northwestern
counties of the CWA, if enough energy from the slowly advancing
upper trough can get far close enough to the area. The better
forcing will be to our northwest closer to the trough itself, and
better shear will be that direction as well with the LLJ being
stronger as you head north into NE tonight. If an isolated storm
were to make it into the area, damaging wind would be the main
threat, but again it is a low probability.

As the trough continues to approach the area heading into Tuesday,
the associated cold front will also move closer through the morning.
The RAP/HRRR show spotty showers potentially in north central KS
ahead of the boundary, while most other models stay dry until the
front itself moves in. Have storm chances increasing along this
front in northern areas early to mid afternoon, while most places
should see the best chances for increasing storm activity during the
late afternoon to evening. Forecast soundings show an eroding cap
during the late afternoon, and CAPE is progged to increase to 2000-
4000 J/kg with 30-40 kt of deep-layer shear (strongest along and
behind the boundary). With flow being parallel to the boundary,
storm mode could get messy as interactions occur, so the window of
opportunity for any tornado risk looks rather brief and more towards
far northeast KS as the front moves in and storms develop. Damaging
wind looks to be the main severe risk with a well-mixed BL and
inverted-V profiles, though large hail can`t be ruled out with a
strong enough updraft. Additionally, will need to watch out for
heavy rain and flooding with Pwat progged to return to 2-2.5", and
possibly training storms along the boundary.

The front looks to stall around southeast KS Wednesday, resulting in
cooler temperatures with highs in the 80s area-wide. Broad upper
troughing across the northern CONUS with embedded shortwaves aloft
keep chances for storms through Wednesday and Thursday, though the
main trough axis looks to pass through the northern Plains Thursday
and push another front through the area that day. Timing and
placement of these waves and the boundary will become more clear as
we get closer to each day, but overall will need to monitor severe
and flooding risks until we get through the 4th of July holiday. It
would be prudent to stay up to date with the forecast until then.

Mainly dry weather is anticipated Friday and Saturday before return
flow early next week brings potential for additional thunderstorms,
although chances are low at this time.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 644 PM CDT Mon Jul 1 2024

Expect VFR conditions for much of the next 24 hours. Numerical
models are forecasting isolated to scattered thunderstorms
developing around the terminal late Tuesday afternoon into
Tuesday evening. Southeast surface winds over 10 KTS with some
minor gusts Tonight, will veer more to the south through the mid
and late morning hours and will increase to 12 to 16 KTS with
gusts of 24 to 30 KTS.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 8 PM CDT this evening for KSZ020-KSZ021-
KSZ034-KSZ035.
Heat Advisory from noon to 8 PM CDT Tuesday for KSZ021-KSZ022-
KSZ023-KSZ024-KSZ026-KSZ034-KSZ035-KSZ036-KSZ037-KSZ038-KSZ039-
KSZ040-KSZ054-KSZ055-KSZ056-KSZ058-KSZ059.

&&

$$

DISCUSSION...Picha
AVIATION...Gargan