143
FXUS63 KTOP 071749
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1249 PM CDT Mon Jul 7 2025

.KEY MESSAGES...

- Scattered thunderstorms are possible from mid-afternoon
  through early evening today with a second round possible
  overnight.

- The storms could be capable of damaging winds.

- There is little change in the weather pattern through the week
  with warm and humid conditions persisting.

&&

.DISCUSSION...
Issued at 252 AM CDT Mon Jul 7 2025

Regional radar showed an MCS moving across southwestern KS at
0730Z with more isolated convection across the WY high plains.
This was occurring around the northern periphery up an upper
ridge over NM and as the mean westerlies remains well north of
the forecast area. Surface obs showed weak high pressure over
much of the central plains. Except for the cold pool from the
MCS to the west, any surface boundary was becoming less defined.

The weather is going to be driven by mesoscale processes more than
anything. Models show a more favorable thermodynamic environment
developing this afternoon with mid-level lapse rates between 6C and
7C resulting in a conditionally unstable airmass with little to no
inhibition. The question is what triggers convection with no obvious
surface boundary or convergence. Perhaps a remnant MCV from this
morning`s convection. The 06Z RAP and 00Z NAM both show a vort max
drifting across northeast KS this afternoon with QPF indicative of
scattered storms. So will showing increasing chances for showers and
storms through the afternoon similar to the 00Z HREF. Shear remains
modest, although a little better than the past couple days with 0-
6km bulk shear around 25KT. And forecast soundings prog around 1000
J/km of downdraft CAPE. So isolated damaging wind gusts looks to be
the biggest concern with the storms.

The forecast keeps a 40-50 percent chance POP through the overnight
period for a possible MCS moves south through NEB. There is progged
to be better shortwave forcing and low level convergence to the
north tonight. But some of the CAMs hint at this MCS weakening as it
moves south, possibly due to the afternoon convection overturning
the airmass. Confidence in the POP forecast is below average given
the weak forcing and mesoscale drivers and is more of a middle of
the road forecast where chances could be higher or lower depending
how things unfold over the next 24 hours. There isn`t much change in
airmass from yesterday so today`s forecast highs should look similar
to yesterdays observed readings.

There remains a chance for showers and storms Tuesday across the
eastern counties. One of a couple scenarios is possible, with the
morning convection weakening as it moves through leaving a weak
boundary for afternoon redevelopment. Or the MCS plows through the
area reducing the instability for redevelopment. Time will tell.

Models show less shortwave activity coming over the upper ridge for
Tuesday night through Wednesday night. So the forecast generally has
a dry forecast with afternoon temps remaining around the 90 degree
mark. There remains a signal for a more amplified shortwave trough
bringing a surface boundary into the area Thursday night and Friday
morning. So there remains some chance POPs in the forecast for this
possibility. After Friday, the general consensus is for the mean
westerlies to remain north of the forecast area with generally weak
flow and a conditionally unstable airmass. So it is difficult to
rule out chances for precip. But models do show a brief break from
the heat for Saturday.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1249 PM CDT Mon Jul 7 2025

VFR conditions expected outside of a couple of chances for
storms during the period. The first opportunity comes between
21-01z with some isolated pop-up storms and the second chance
comes after midnight as a complex of storms moves towards
terminals, but weakens as it does so. Confidence in storms
impacting sites during both timeframes are low, so have covered
the potential with two PROB30 groups.

&&

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

&&

$$

DISCUSSION...Wolters
AVIATION...Flanagan