Flash Flood Warning 20, NWS Topeka, KS

Area Forecast Discussion
National Weather Service Topeka KS
645 PM CDT Fri Jun 6 2025

.KEY MESSAGES...

- Showers and thunderstorms impact the area overnight tonight
  into Saturday morning. A storm to two could be strong to
  severe and produce hail up to 1" in diameter, wind gusts up to
  60 MPH, and locally heavy rainfall.

- Additional chances (20-40%) for storms come Sunday afternoon and
  evening with the potential for a few strong to severe storms.

- Dry conditions expected Monday through Wednesday.

&&

.DISCUSSION...
Issued at 214 PM CDT Fri Jun 6 2025

Quasi-zonal flow persists across the central CONUS this afternoon
with the forecast area sandwiched between two shortwaves: one over
the Mid-Mississippi Valley and another stronger wave approaching
from the Rockies. Subsidence in the wake of the first wave has lead
to lessening coverage of showers this afternoon. The airmass remains
largely uncapped, but a lack of forcing keeps chances for any
showers/storms this afternoon and evening rather low (20%). As the
second perturbation ejects across the Plains tonight into Saturday
morning, a very similar convective evolution to last night is
expected with initial storms across the High Plains growing upscale
into a MCS and progressing southeast across southern Kansas into
northern Oklahoma. As for northeast Kansas, the passing wave is
farther north and stronger than last night, so expect more of the
area to be impacted by scattered showers and thunderstorms, mainly
from midnight through mid-day on Saturday. PWATs remain around 1.5"
and forecast soundings show deep warm-rain processes and skinny CAPE
that will allow storms to be efficient rainfall producers. Rainfall
rates of 1-1.5" per hour are possible with any storms, although
precipitation should be progressive enough to limit any flooding
concerns. Instability is limited, but can't rule out a stronger
storm or two given effective shear of 30-40kts. Subsidence in the
wake of the perturbation and drier air filtering in should lead to
dry conditions by Saturday afternoon that continue into Saturday
night.

A northern stream trough dives south across the Northern Plains and
upper Midwest on Sunday, shunting a surface boundary through the
area during the daytime hours. Sufficient moisture and lift along
and ahead of the front favors convective development during the
afternoon. Placement of the boundary by mid-day Sunday remains in
question, but a general model consensus has the front along or south
of Interstate 70 by that time. SBCAPE of 2000-2500 J/kg and
effective shear of 30kts will support strong to severe storms during
the afternoon and evening before the front shifts south late Sunday.
Elongated, but straight hodographs favor large hail and damaging
winds as the main hazards.

Yet another wave and surface front dives south across the Plains and
Midwest on Monday, but uncertainty remains in quality of moisture
and associated precipitation chances with this wave. The majority of
ensembles (~80%) keep the area void of precipitation, so have
maintained a dry forecast for Monday. Surface ridging is progged to
move in by Tuesday with a mid-level ridge moving overhead on
Wednesday. This should lead to a dry period before another trough
approaches the area late Wednesday into Thursday. Temperatures hold
steady in the upper 70s to low 80s Friday through Monday before
warming into the mid to upper 80s on Wednesday.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 644 PM CDT Fri Jun 6 2025

Main thing to watch will be coverage of convection tonight into
Saturday morning. A few showers have developed in south central
KS, and while those may become spotty across eastern KS this
evening as well, chances are focused on the cluster of storms
progged to move across western KS tonight. Most of this activity
should stay south of terminals, but there remains some variation
between CAMs on how far north it could get and on exact timing.
There also looks to be another batch of storms that comes out of
Nebraska early in the morning, which may or may not impact
terminals. Have attempted to capture both of these within the
PROB30 group given the uncertainties for now. MVFR cigs/vis
appear likely within any storms. Some guidance suggests those
conditions could be more widespread in the region while other
models suggest they would be confined to storms, so think
limiting MVFR conditions to the PROB30 group makes most sense at
this time.

&&

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

&&

DISCUSSION...Flanagan
AVIATION...Picha

Hazardous Weather Outlook
National Weather Service Topeka KS
201 PM CDT Fri Jun 6 2025

KSZ008>012-020>024-026-034>040-054>056-058-059-071915-
Republic-Washington-Marshall-Nemaha-Brown-Cloud-Clay-Riley-
Pottawatomie-Jackson-Jefferson-Ottawa-Dickinson-Geary-Morris-
Wabaunsee-Shawnee-Douglas-Lyon-Osage-Franklin-Coffey-Anderson-
201 PM CDT Fri Jun 6 2025

This Hazardous Weather Outlook is for central Kansas, east central
Kansas, north central Kansas and northeast Kansas.

.DAY ONE...This afternoon and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

A storm to two could be strong to severe Saturday morning and
produce hail up to quarter size and damaging wind gusts.

&&

More detailed information can be found at:
www.weather.gov/media/top/DssPacket.pdf