textproduct: Topeka

KEY MESSAGES

- A Red Flag Warning has been issued for north central Kansas areas for this afternoon.

- Severe storms possible Friday afternoon into the evening as a cold front moves into the area. All hazards possible with a 15-30% chance for severe storms to impact any one area. All severe hazards will likely be possible especially over eastern areas.

- Cooler overnight and early morning temperatures set up Saturday and Sunday morning. Sunday looks to be the overall best setup with clear skies and calm conditions into the overnight and early morning hours.

- Elevated fire weather may still occur Saturday over north central areas if the winds are strong enough.

DISCUSSION

Issued at 207 PM CDT Thu Apr 16 2026

Late this morning, water vapor satellite showed an amplified trough extending from the MT/Canadian border south-southwest into NV. An upper level trough was lifting east-norheast across the Great Lakes.

The 17Z surface map showed the warm front reforming well to the north across southern ND and northern MN. Winds were southerly and richer moisture across northern OK/southern KS was beginning to advect north across the CWA.

Friday through Friday night:

The amplified H5 trough across the Western US will shift east across the Plains Friday night. Strong low-level CAA across the northern Plains will cause a surface cold front to push southeast across NE late Tonight, then southeast across western KS and into the northwest counties of the CWA by 18Z FRI. There are differences within the CAMs and deterministic models in the speed of the front, with most model solutions showing the front moving across northeast and east central KS during the mid and late afternoon hours, and may clear the far southeast counties during the early evening hours of Friday.

Ahead of the front, southerly low-level winds will advect rich Gulf moisture north- northeast across the CWA Friday morning, into the early afternoon hours. As the H5 trough approaches the central high Plains, 500MB temperatures will decrease causing steep mid level lapse rates. Ahead of the front. MLCAPEs will increase to 3000-4000 J/KG with effective shear of 50 to 65 KTS after by 20Z.

The big question is how fast to the southeast will the front move during the afternoon hours. I took an average position of all model guidance, with the front being on a Seneca to MHK to Council Grove line by 20Z, about the time storms should begin to develop along the front or isolated storms within the warm sector ahead of the front may develop. The 12Z HRRR solutions shows the front farther east by 21Z extending from northeast Jefferson County, southwest to Osage City, then southwest to an EMP line, which means developing storms may not become severe until reaching the far east central and southeast counties of the CWA.

The 2nd question is storm mode. Several of the CAMs are showing discrete supercells developing within the warm sector ahead of the surface front. Through the afternoon hours the 850mb winds will begin to veer more to the southwest and west, thus, the richer Gulf moisture may begin to advect from southeast KS into MO. Almost all the numerical models show a quick transition to a back building squall line due to the QG forcing (DCVA and height falls) providing for strong ascent spreading over the cold front and warm sector ahead of the H5 trough.

If discrete storms manage to develop in the warm sector across the eastern counties of the CWA, the forecast hodographs are curved between the sfc and 1 KM, thus, there will be low-level streamwise horizontal vorticity generated in which discrete storm updrafts will tilt and stretch the horizontal vorticity into the vertical for possible tornadogenesis. a few of which could be strong. large hail of 2"+ will be possible with any discrete supercell thunderstorm along with isolated damaging RFD winds. Also, there could be an hour or two where storms going up the along the surface cold front could remain semi-descrete for possible tornadoes. But once the line develop the primary hazard would become damaging wind gusts, but as the 0-3 KM wind becomes more perpendicular to the line we could see meso vortex tornadoes within the QLCS line. A few embedded supercells within the line could produce large hail of 2+ inches. The severe line of storms should move southeast of the CWA after 7 PM.

The RRFS CAM shows more in the way of training thunderstorms across the southeast counties of the CWA. If there is training storms across the southeast counties, then there could be some flooding and even flash flooding southeast of I- 35 during the late afternoon and evening hours. Areas southeast of I-35 may see 1 to 2 inches of rainfall with some locally higher amounts in Coffee, Franklin, and Anderson Counties. Council Grove to Topeka may pick up around 0.5" of rainfall. Areas west of a Abilene to Marysville line will see less than 0.1" of rainfall.

Saturday through Sunday:

The H5 trough axis will move east across the Plains on Saturday, then east across the the Mid MS River valley Saturday night. There may be a few showers developing Saturday under the H5 trough axis. Highs Saturday will only reach the upper 50s east to lower 60s west.

Saturday night, a surface ridge of high pressure will build southeast across KS. Light winds and dry air mass in place will cause overnight lows to drop to near freezing across the northern counties with mid 30s elsewhere across the CWA. Most of the area could see a light frost by sunrise on Sunday. So you may want to cover any of your outdoor plants.

The H5 trough will shift east across the eastern US. KS will be under northwest mid level flow and the surface ridge of high pressure will move southeast into eastern TX. Southwest surface winds will warm temperatures into the lower 70s east and mid 70s west.

Monday through Thursday:

An H5 ridge across the western US will slowly shift east across the Plains by mid week. Temperatres will warm back into the lower to mid 80s.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 559 PM CDT Thu Apr 16 2026

Models show a strong pressure gradient through the night with surface gusts persisting. This along with turbulent mixing is expected to mitigate wind shear potential. The winds along with continued moisture advection should also bring MVFR CIG over the terminals late this evening. This could come in below 1 KFT at TOP and FOE for a brief period but think the overall trend should be to keep CIGS MVFR. As for TS, most of the CAMs show initiation along the front between 18-21Z. Confidence in where the front will be at this time is only medium as some CAMs try to push it just east of FOE by 21Z. The probability for TS is high enough to include in the forecast for TOP and FOE, but there is a decent chance TS develop just east of MHK so may only carry a VCSH for a few hours.

FIRE WEATHER

Issued at 150 AM CDT Thu Apr 16 2026

A Red Flag Warning has been issued for north central Kansas areas for this afternoon due to minRH values dropping to the upper teens as mixing deepens and the pressure gradient tightens through the afternoon. Winds will gust to around 30 mph at times but remain out of a southerly direction. Expect critical rangeland fire conditions to set up as 1 hr fuels are expected to drop below 10 which would cause fuels to burn very efficiently.

On Saturday afternoon, northwest wind gusts may reach 30 MPH and minimum wil range between 15 to 20 percent across north central KS. Fuels may still remain dry across Cloud and Ottawa counties, thus any extreme fire danger for these two counties may require a red flag warning Saturday afternoon.

TOP WATCHES/WARNINGS/ADVISORIES

Red Flag Warning until 9 PM CDT this evening for KSZ008-KSZ020- KSZ034.