textproduct: Topeka

KEY MESSAGES

-One round of rain is expected this morning, with another arriving tonight and early Friday.

-Heavy rainfall will be the main hazard with storms today and tomorrow.

-The rain and cloud cover will keep temperatures on the cool side of average for a few days.

-Heat and humidity build back in this weekend.

DISCUSSION

Issued at 224 AM CDT Thu Jul 23 2026

At 07Z, water vapor imagery and H7 analysis showed a mid-level ridge centered over TX/OK/NM with a few shortwaves on its northern periphery. A batch of showers and storms had developed ahead of one wave over western KS/NE. The environment ahead of the wave in central KS featured 500-1000 J/kg of MUCAPE, 7.0-7.5 C/km mid-level lapse rates, and weak shear. Further east, instability was minimal and lapse rates were less impressive. Thinking is that showers will expand as the system slowly moves east through the morning. Thunderstorm chances remain highest in central KS given the aforementioned parameters, with a general weaken trend expected into eastern KS later this morning. The most likely hazard with storms will be heavy rainfall. Forecast soundings show a fairly saturated column and pwats in the 1.9-2.0 inch range in more central portions of the state. QPF is around an inch of rain in central/north-central KS, and lower amounts eastward where lift and instability will be weaker. Rain and residual cloud cover will keep temperatures on the cool side of average today with highs in the upper 70s and low 80s.

Focus then turns to another round of rain expected tonight as another shortwave trough axis moves over the area. A similar environment will be in place, except that pwats are expected to be a bit higher due to stronger low level moisture transport and theta-e values. Overall lift looks somewhat weak, which leads to some uncertainty regarding how widespread precipitation will become, but there is at least potential for heavy rainfall leading to localized flooding, especially in locations that receive rain today. The axis for heaviest rainfall still looks to be along and north of I-70 with Friday's round, where the HREF and NBM both have about a 50-70% chance for at least one inch of rain. Rain should taper off from west to east through midday, with possibly just a few lingering showers by mid-afternoon.

This weekend, the mid-level ridge axis will quickly expand back to the north. Heat and humidity will respond with highs back in the 90s and heat index values exceeding triple digits for most. The hottest days look to be Sunday and Monday before the ridge possibly weakens as perturbations rotate around the northern edge. Those perturbations are difficult to time at this range, but they could bring some rain chances back to the forecast by the middle of next week.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 1216 AM CDT Thu Jul 23 2026

For the 06Z TAFs, have adjusted timing of SHRA at all sites slightly, to begin precipitation a bit sooner. Further adjustments could be warranted with models still showing a few different solutions. The potential for TS still appears higher at KMHK so maintained the VCTS forecast. Have kept VFR CIGS but there could be a brief period of MVFR as rain wraps up late morning and midday.

TOP WATCHES/WARNINGS/ADVISORIES

None.