503
FXUS63 KTOP 180819
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
319 AM CDT Sun Aug 18 2024

.KEY MESSAGES...

- Showers and thunderstorms are possible today (15-30%) and
  tonight (30-55% chance). A few storms this afternoon and
  evening could be strong to severe.

- Below normal temperatures to start the workweek before
  temperatures gradually warm into next weekend.

&&

.DISCUSSION...
Issued at 319 AM CDT Sun Aug 18 2024

Upper ridging persists across the Southern Plains and Desert
Southwest this morning with a couple of perturbations rounding the
ridge. Surface high pressure is in control of the middle of the
CONUS, keeping conditions across the forecast area benign overnight.
Lift associated with the aforementioned waves along with isentropic
ascent have generated showers and storms across South Dakota and
Nebraska. As these features continue around the ridge, sufficient
lift and saturation in the mid-levels will support the development
of showers and storms later this morning into the afternoon.
Uncertainty remains in coverage and intensity of storms with CAMs
showing a wide variety of solutions. Several CAMs show a complex of
storms moving along the instability gradient into northeast Kansas.
Others suggest a more scattered natured to convection with recent
runs of the HRRR being an outlier solution, showing little to no
precipitation across the area through the day. The passing waves are
fairly weak and isentropic ascent becomes better focused across
eastern Kansas this afternoon and evening. This supports
isolated to scattered storms through the afternoon and evening
as the most probable solution. Elevated instability of 500-1000
J/kg coupled with 45-50kts of effective shear would support a
low-end severe threat and the strongest storms could produce
hail up to quarter size and damaging wind gusts. If an organized
MCS moves into the area, the potential for severe storms
increases with damaging wind gusts being the main hazard.

CAMs are in good agreement with additional storms developing this
evening and overnight as a slightly stronger wave progresses
southeast and isentropic ascent increases. Instability is progged to
be weak (<500 J/kg) which should preclude any severe weather
potential.

A surface high builds south on Monday and Tuesday bringing in drier
air and keeping temperatures in the 80s. Another wave rounds the
ridge Monday night into Tuesday, bringing a small chance of
precipitation across central Kansas. Upper ridging builds overhead
Wednesday with gradually warming temperatures and dry conditions
into next weekend.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1227 AM CDT Sun Aug 18 2024

VFR conditions expected. Fog potential is low this morning given
increasing cloud cover and 10-15kt winds a few hundred feet off
the surface. A complex of showers and storms moves towards
terminals by late morning or early afternoon which could bring
gusty winds and reduce visibility. Timing and coverage remains a
bit uncertain, but confidence has increased enough to input VCTS
for a few hours.

&&

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

&&

$$

DISCUSSION...Flanagan
AVIATION...Flanagan