205
FXUS63 KTOP 051905
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
205 PM CDT Fri Jul 5 2024

.KEY MESSAGES...

- Chance of thunderstorms tomorrow afternoon, some of which
  could be severe.

- Frequent thunderstorms will pose a risk of flooding through
  Sunday.

- Below average temperatures will continue through the middle of
  next week.

&&

.DISCUSSION...
Issued at 203 PM CDT Fri Jul 5 2024

Northwest flow continued to keep a cooler and drier airmass in place
for this afternoon. High temperatures were forecast in the low to
mid 80s, slightly below average for this time of the year. A low
amplitude shortwave could be identified on satellite imagery, with
enhanced convection and cold cloud tops in northwestern KS. This
impulse will travel across the state, bringing a slight chance of
rain this afternoon and evening. However, with dewpoint depressions
near 40 degrees F, it is expected that rain will not be able to
reach the surface.

A stronger disturbance was seen on water vapor imagery upstream in
southern Saskatchewan/eastern Montana. This wave will track to the
SE overnight and tomorrow, and will foster development of a surface
low pressure in western Kansas. Warm air advection will strengthen,
and our high temperatures will approach 90. As the system gets
closer, convection is likely to form in central KS/southern NE.
Eastern KS will not have a very supportive environment for severe
weather, with CAPE values struggling to reach 1000 J/Kg as a result
of the drier airmass in place at the surface. That being said, well
established thunderstorms will be capable of producing damaging wind
gusts as they move SE across the state. Most models indicate that
the higher severe wind threat will be south and west of a line from
Concordia to Salina, where convergence along the boundary is
stronger.

Multiple more waves rounding the base of the trough will continue
into Sunday, and frequent thunderstorms are likely during the day.
As a result of the extensive cloud cover, highs will only be around
80 on Sunday. Moisture is going to increase, and the threat for
flooding will increase somewhat on Sunday. Some areas south of I-70
have received over 400% of their average 14-day precipitation,
suggesting that soils are very saturated already. This weekend,
those areas south of I-70 have a moderate (40-60%) chance of
exceeding 1 inch of rain, according to the NBM.

The trough axis is forecast to pass on Monday, bringing an end to
the rain chances. This will reinforce the cooler air, giving us
another day with high temperatures right around 80. This trough is
likely to keep Beryl and its associated moisture away from Kansas.

As the upper air pattern becomes less active, temperatures should
warm up and become closer to average, with upper 80s through the
middle of next week. The next trough passage suggested by the models
is Wednesday overnight, and that is when the chance of thunderstorms
will return to the forecast.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1157 AM CDT Fri Jul 5 2024

VFR conditions will prevail through the period. This afternoon,
gusty northwesterly winds to 20 kt will continue. Diurnal cumulus
will form, and promptly dissipate by sunset. After sunset, a high
pressure system will pass to the south, and light winds will turn
from NW to S/SW. The light winds may lead to patchy fog, but
confidence is low.

&&

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

&&

$$

DISCUSSION...Montgomery
AVIATION...Montgomery