517
FXUS63 KTOP 141720
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1220 PM CDT Tue May 14 2024

.KEY MESSAGES...

- Mostly dry weather is expected today, aside from a stray shower in
far eastern KS this morning.

- Shower and storm chances (50-80%) return Wednesday into Thursday.
Confidence lowers for rain chances into the weekend.

- Temperatures stay near average for the next few days, then
  warm up for the weekend.

&&

.DISCUSSION...
Issued at 402 AM CDT Tue May 14 2024

The 500mb low is situated over western MO early this morning,
followed by weak ridging over the central Rockies and the next low-
amplitude shortwave over the Intermountain West. Another area of low
pressure aloft is noted off the coast of CA. At the surface, we are
left in a narrow ridge axis between the low in MO and low pressure
in the Dakotas and WY. A few deformation showers remain in far
eastern KS on the north and west side of the low to our east, and an
isolated shower may still clip our eastern counties this morning.
The system should move far enough east after sunrise to bring rain
showers to a complete end.

Most of today is expected to be dry as we find ourselves between the
two systems and the ridge passes through the area. Clouds may be a
bit slow to move out in far eastern counties, though highs are still
forecast in the 70s area-wide, near average for the middle of May.
There are low chances (20-30%) for rain to move into central KS
after midnight, but forecast soundings take time to saturate and the
better ascent arrives toward Wednesday afternoon and especially
evening as the shortwave energy ejects out from the upper trough.
For this reason, the highest PoPs (50-80%) continue to be focused in
the 00-12Z Thursday time frame. Deep-layer shear is forecast to be
in the 30-40 kt range, which could support a few more organized
storms if a stronger updraft can get going. "If" is the key word
there - the best instability (CAPE of 1000-2000 J/kg) looks to be
confined to a narrow corridor along the southwest edge of our
forecast area, with instability dropping off as you go north and
east. Am not sold on stronger storms developing in areas where only
a few hundred J/kg of MUCAPE exists. The amount of instability that
storms have to work with may depend on how far north a weak warm
front can make it during the day Wednesday, so this will bear
watching through the next 36 hours or so.

Instability and shear both weaken into Thursday, not enough to
eliminate chances for thunderstorms, but enough to lower the
likelihood of severe weather. There are still some model differences
in how the pattern evolves heading into the end of the week - some
suggest the southern stream trough phasing into the northern stream
by Friday, while others suggest the southern stream develops into a
closed low over the area on Friday. The latter scenario has a
greater chance of keeping some showers and thunderstorms around on
Friday in eastern areas in particular, so lower-end PoPs remain in
the forecast.

Ensemble solutions diverge further through the weekend into early
next week, so confidence in rain chances continuing through this
time period is rather low. Saturday currently looks like the warmest
day, as the NBM 25th percentile has forecast highs into the 80s for
nearly the entire area with the higher end of the guidance pushing
90 for some locations. So it at least appears likely to see warmer
temperatures on the horizon as we head into the weekend.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1220 PM CDT Tue May 14 2024

A steady north wind around 10 kts will continue this afternoon.
Ceilings will stay VFR through most of tonight with just some VFR
cumulus this afternoon. As winds become more easterly towards
sunrise though, there is a decent chance that MVFR ceilings move
back in from the east towards sunrise. A few showers will be
possible after sunrise as well, though confidence on timing and
coverage remains low.

&&

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

&&

$$

DISCUSSION...Picha
AVIATION...Reese