textproduct: Topeka

KEY MESSAGES

-Temperatures remain on the cool side of average through the end of the week.

-Wet weather could return tonight with scattered showers. Better chances for rain arrive Thursday night and early Friday.

-Next week could feature a few more opportunities for rain and thunderstorms along with warmer weather.

DISCUSSION

Issued at 234 PM CDT Wed May 20 2026

High pressure remains in place, keeping conditions cool and fairly dry through the lower levels of the atmosphere today. Southwest flow exists in the mid-levels with a longwave trough axis over the Rockies into the Desert Southwest. Isentropic ascent will increase tonight as winds turn more to the south/southwest through the low levels, also bringing in more moisture at those levels. Thus, POPs increase and CAMs show scattered showers overnight into early Thursday morning. There could be a lightning strike or two, but instability looks to be very limited. Ascent decreases during the day tomorrow, but low clouds will likely remain for much of the day.

The better chance for more widespread rainfall appears to be Thursday night and early Friday morning as a shortwave moves through the southwest flow aloft. However, recent model runs seem to have that wave further south and east than the previous run, which could shift the axis of heaviest rain eastward a bit. Far eastern KS has the best chance for the higher rainfall totals Thursday night and early Friday with most models hinting at 1.0 to 1.5 inches by midday Friday. Flooding will be a concern in eastern KS, especially since some locations have seen between 2.0 and 4.0" in the last week.

Temperatures will eventually begin trending back upward this weekend, when rain chances appear to be more confined south and east of the area near a surface boundary. Looking at the longer term trends, models seem to agree on a small cut-off H5 low moving northward over the area around mid-week, which may be quickly followed by another shortwave trough. Both could have enough moisture and lift to make for a few wet and stormy days sometime mid- week. Strong southerly flow also looks to bump temperatures well into the 80s most days.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 1231 AM CDT Thu May 21 2026

Will keep an ENE surface wind in place to begin the period gradually veering to the E through mid morning. Weak ascent above the slowly receding surface ridge will be in place ahead of a trough digging into the western CONUS. Periods of -SHRA with a few embedded storms over central Kansas possible early this morning. Right now, looks like potential for more showers and possibly embedded storms increase by this evening but confidence is still too low to mention. Also, IFR conditions may set up better just west and southwest of the area, so have held off mention of lower than marginal VFR for now as well. Will continue to evaluate trends into the 12Z forecast for both these elements toward the end of the 12Z period.

TOP WATCHES/WARNINGS/ADVISORIES

None.