542
FXUS63 KTOP 061736
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1236 PM CDT Sat Jul 6 2024

.KEY MESSAGES...

- Storm chances increase for areas along and north of Interstate
  70 late this afternoon into the evening. Some storms could be
  severe with damaging wind gusts being the main hazard.

- Additional rounds of showers and storms move through Sunday
  into Monday morning. Locally heavy rainfall with these storms
  will pose a risk for flooding.

- Slightly below-normal temperatures expected Sunday and Monday
  before returning to near-normal values Tuesday-Friday.

&&

.DISCUSSION...
Issued at 303 AM CDT Sat Jul 6 2024

Northwest flow aloft continues across the Plains early this morning
with surface ridging in control of the region. Light winds and clear
skies have allowed temperatures to cool into the 60s. Dewpoint
depressions are less than 5 degrees across the area, but elevated
winds at and just off the surface have kept enough mixing to
preclude fog development to this point. There could be some patchy
fog through sunrise when any fog that does develop will quickly burn
off.

The surface high slides east through the day as a wave of energy
dives southeast across the Dakotas. A surface low develops in
response across eastern Colorado and western Kansas with modest
southerly surface winds bumping temperatures into the mid 80s and
low 90s this afternoon. The aforementioned wave and associated
surface boundary will lead to convective development across Nebraska
and western Kansas this afternoon. Large-scale ascent will lead to
upscale growth of convection as it progresses east-southeast during
the late afternoon and evening. Instability is rather weak for
summertime standards (MUCAPE of less than 1000 J/kg), but 30-35 kts
of effective shear and inverted-V soundings could support severe
wind gusts as a line of storms moves into the area from the
northwest between 5-7PM. The complex is expected to weaken as it
pushes southeast into a less favorable environment, although CAMs
are in good agreement in a stronger portion of the line continuing
east across southern Nebraska and far northern Kansas at the nose of
the LLJ. The severe threat ends by 10-11pm as storms continue to
weaken and exit the area. Storm movement looks to be progressive
enough to limit flooding concerns with this round of convection.

There could be a lull in precipitation tonight into early Sunday
before a couple additional waves of energy eject across the area
into Monday morning. Moisture content rises with PWATs reaching 1.25-
1.70" and forecast soundings show skinny CAPE profiles and deep warm
cloud processes. Heavy rainfall will be the main hazard with these
storms; HREF members show the potential for a quick 1-1.5" of rain
from any storm. However, the overall coverage of storms remains
uncertain with CAMs suggesting more of a scattered to widely
scattered coverage of storms. If storms are more widespread in
nature or one area is impacted with a few rounds of storms, flooding
will become more of a concern, especially given the wet
antecedent conditions.

Rain chances end by Monday afternoon and a quieter pattern sets up
into the middle of next week. After a few cooler days with highs in
the low 80s Sunday and Monday, temperatures return to near-normal
values Tuesday through Friday with highs in the mid 80s to low
90s.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1217 PM CDT Sat Jul 6 2024

A VFR forecast is anticipated to prevail for now with overnight
clouds increasing across the area so any radiational cooling
effect may be limited. Showers and storms may also stay to the
north and southwest of the terminals so certainty remains too
low to include mention other than mid clouds for the overnight
period. There may be more widespread precipitation develop into
the morning hours but confidence is still too low for the 18-24
hrs out. Expecting a LLJ to develop around midnight through
sunrise which looks to generally weaken only a few hours after
developing. Marginal WS conditions expected briefly around
FL015.


&&

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

&&

$$

DISCUSSION...Flanagan
AVIATION...Drake