textproduct: Topeka

KEY MESSAGES

- Near-record warmth and dry conditions continue through Monday.

- Rain and thunderstorm chances increase Tuesday through Thursday, with highest chances (70-80%) coming Tuesday night through Wednesday night.

- Cooler temperatures are forecast late late this week.

DISCUSSION

Issued at 200 PM CDT Sun Oct 11 2026

Early this afternoon water vapor satellite imagery along with upper air anaylisis showed The phasing of a southern stream upper trough with the northern stream upper trough across the western US. An upper level ridge was located from eastern TX, northward along the KS/MO border, north-northeast into IA. The now extra tropical upper trough, the remnants from hurricane Isaias, was lifting northeast across eastern KY, eastern TN, and north central GA.

The 17Z surface observations showed a cold front extending from northern MN, southwest across eastern SD, then southwestward into southwest NE and northeast CO. Across eastern KS, southerly winds were increasing to 15 to 20 MPH with some gusts of 25 to 30 MPH. Temperatures were in the upper 70s to lower 80s.

Today through Monday:

The upper trough along the western US coast will dig southeast into western NV and extend southeast into northwest Mexico. The H5 ridge axis across the western Gulf will amplify northward across the mid MS River Valley. A lee surface trough across the central high Plains will deepen in response to strong southwesterly mid level flow across the central Rockies. The southerly winds will warm afternoon high temperatures into the lower 90s. The highs may be near or tie record highs for Monday. There will be scattered high thin clouds.

Monday night through Tuesday night:

A southwesterly LLJ of 40-45 KTS will increase through the late evening and overnight hours. The HRRR and RAP models show elevated showers developing through the early morning hours of Tuesday across northeast KS in response to the transport of richer moisture northward by the LLJ.

The H5 trough will slowly push east into UT and extend southward across AZ. The southwesterly H5 flow will increase to 30 to 40 KTS across the CWA, with the H5 jet max across western KS of 50-55 KTS. The surface front across NE will move southeast into the northern counties of the CWA during the morning hours of Tuesday. The NAM12 pushes the front southeast to I-35 by 00Z WED. While the GFS and ECMWF show the front becoming stationary across the northern counties of the CWA Tuesday afternoon. The NAM12 develops 1500-2000 J/KG of MLCAPE ahead of the front during the late afternoon hours. While the GFS/ECMWF only shows 1000-1200 J/KG of MLCAPE. However, as the front approaches, thunderstorms will develop due to surface convergence and ascent ahead of the H5 jet max. The storms may be severe given 40 to 50 KTS of effective shear. Even if the NAM12 instability is a bit over done, the low-level veering wind profile and curved hodograph show the potential for supercell thunderstorms. There will be a stronger EML over spreading the CWA, which may limit the coverage of thunderstorms. Any supercell thunderstorm may produce all hazards. There remains uncertainties based on the location of the front Tuesday afternoon and the strength of the CAP, but eventually the convergence along the front should cause scattered to numerous thunderstorms to develop during the evening hours. Some of the storms may be severe ahead of the front into the evening hours.

There remains much uncertainty on where the front may become stationary overnight. The NAM12 moves the front south of the CWA to the KS/OK border after midnight. While the GFS and ECMWF show the front becoming stationary along the southeast counties of the CWA. Strong isentropic lift over the front will cause showers and elevated thunderstorms to continue through the early morning hours of Wednesday.

Wednesday through Thursday:

The extended range models are in better agreement. The GFS lifts the upper low over the Four Corners region northeast across north central NE by 18Z WED, which begins to phase with an H5 trough digging southeast out of central Canada into the Upper Midwest. The ECMWF shears apart the upper low over the Four Corners region, while an amplified H5 trough digs southeast out central canada into the upper Midwest by 00Z FRI.

There remains some uncertainty on where the frontal boundary will be located. The GFS shows the boundary remaining stationary across the far southeast counties, which would keep most surface based storms to our south. The ECMWF shows the front slowly shifting north Wednesday night into Thursday morning. Both extended range models show a strong front pushing southeast across the CWA on Thursday, as strong low-level CAA develops across the northern and central plains to the west of an amplifying H5 trough across the Upper Midwest.

Isentropic lift with richer 850mb moisture advection will cause showers and elevated thunderstorms Wednesday into Thursday morning. The ensemble spreads of the NBM and LREF show PWs of 1.5 to 2.1" on Wednesday, so there could be some minor flooding. The stronger elevated storms that may have mid level rotation may produce larger size hail, especially across east central KS closer to the front. If the front shifts a bit north, then surface based storms may produce damaging wind gusts along with the larger hail.

The 850mb winds will veer more to the southwest Wednesday night, thus the heavier rain may shift east. There may be enough residual moisture for showers and thunderstorms on Thursday ahead of the stronger fast moving front.

Thursday night through Saturday night:

The H5 trough across the Midwest will dig southeast across the eastern US and amplify. A 1035 mb surface ridge will build southeast cross KS late Friday night into Saturday.

Expect cooler temperatures Friday and Saturday, with high only reaching the lower to mid 60s. Lows will reach the mid to upper 30s Saturday morning. If the winds diminish before sunrise on Saturday, there could be some patchy front across the northern counties of the CWA.

Sunday:

The surface ridge will shift southeast of the area and light southerly winds will help high temperatures to warm into the lower 70s.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1234 PM CDT Sun Oct 11 2026

Expect VFR conditions at the terminals through the next 24 hours. As a southwesterly low-level jet at 1200 feet increases to 40 to 45 KTS through the night. There maybe some moderate vertical wind shear of 25 to 30 KTS at the terminals from 6Z - 13Z MON.

CLIMATE

Issued at 216 AM CDT Sun Oct 11 2026

Record High Temperature Information:

October 11 Current Record Forecast ---------------------------------------------- Topeka 94, set in 1975 88 Concordia 94, set in 1975 90

October 12 Current Record Forecast -------------------------------------------------- Topeka 93, set in 1899 and 2024 92 Concordia 93, set in 1899 93

October 13 Current Record Forecast ---------------------------------------------- Topeka 91, set in 1975 92 Concordia 90, set in 1975 87

Record Highest Minimum Temperature Information:

October 12 Current Record Forecast -------------------------------------------------- Topeka 68, set in 1890 and 1899 70 Concordia 67, set in 1975 72

October 13 Current Record Forecast --------------------------------------------------------- Topeka 69, set in 1962, 1968, and 1975 70 Concordia 70, set in 1920 65

TOP WATCHES/WARNINGS/ADVISORIES

None.