textproduct: Topeka

KEY MESSAGES

- There is a 15-30% chance of showers and storms Thursday morning and again Thursday evening.

- Hot and humid weather is forecast Friday through Sunday giving a taste of summer before a cold front moves through Monday. Scattered showers and storms will be possible Friday through Monday, some of the storms could be strong to severe.

DISCUSSION

Issued at 337 AM CDT Wed May 13 2026

Early this morning, water vapor satellite and upper air analysis showed an upper level trough centered north of Lake Superior, with a trough axis extending south-southwest into the mid MS River Valley. A amplified upper ridge axis extended from northern Mexico/west TX, north-northwest across the central Rockies. An upper level trough was moving onshore across the Pacific Northwest. The Plains were under northwesterly mid and upper level flow.

The 6Z surface map showed a cold front extending from southern MI, southwest across central IL, southwest across central MO, into southeast KS, then southwest into the TX PNHDL and northeast NM. Light northeast winds were observed across the CWA with temperatures in the mid 50s north to lower to mid 60s central and south.

Today through Tonight:

The H5 ridge across the central Rockies will move east across the Plains. Expect mostly sunny skies with light winds becoming southeasterly through the late afternoon hours. Highs will be slightly cooler with upper 70s to lower 80s. The surface front will stall out across OK and undergo frontolysis Tonight A southerly low- level jet of 40 to 45 KTs will develop across central KS and advect residual Gulf moisture northward into central KS. There may be enough isentropic lift to the east of the moist(theta-e) axis for a few isolated showers and storms to develop late Tonight and into the early morning hours of Tuesday. Several CAM solutions show 200-500 J/KG of MUCAPE across the CWA, so some of the stronger elevated storms may produce small hail as they move east across the area during the early morning hours of Thursday.

Thursday through Friday night:

The morning showers and storms will weaken as the isentropic lift diminishes by the mid morning hours and shifts east into MO. The H5 ridge will shift east across the lower mid MS River valley. The Pacific Northwest H5 trough will move east across the Great Basin into the northern highs Plains. A stronger mid level perturbation on the south side of the H5 trough axis will move east into western NE/KS. Southerly winds will advect richer moisture northward across central and eastern KS. A surface low will develop across northwest/north central KS by afternoon. The surface dryline will shift east across southwest KS into central KS (or at least a pre-dryline surface trough). Surface convergence and ascent ahead of the H5 perturbation may cause a few thunderstorms to develop. The effective shear of 40 to 50 KTS along with MLCAPE of 2000-2500 J/KG across central and north central KS would be favorable for supercell thunderstorms, which could produce large hail, isolated damaging wind gusts and possible tornadoes, given curved hodographs. However, the capping inversion looks strong and this may suppress deep moist convection from developing. The NAM12 shows no convection developing Thursday afternoon along the dryline but the ECMWF and GFS do show QPF across the western counties. If scattered supercells develop they may merge into line segments and move east across northeast and east central KS during the overnight hours. But if the Cap is strong any isolated storms may dissipate a few hours after sunset.

Friday into Saturday night:

The stronger mid level flow will shift northward into NE. An upper trough will dig southeast across the western US. A weak cold front will drift south into the northern counties of the CWA, and if the CAP is weaker, scattered thunderstorms will develop. Once again the Nam12 shows no convection developing across the CWA Friday afternoon into Friday night. The 850mb winds look more veered but surface winds may be easterly along the stationary front. MLCAPES will increase to 2000- 3000 J/KG and the effective shear will be around 30 KTS across the northern counties, so there could be supercell thunderstorms developing north of I-70, if the CAP breaks. The primary hazard will large hail and damaging wind gusts.

Sunday through Tuesday:

The western H5 trough will dig southeast into the southwestern US. The strong southwesterly mid level flow will increase the effective shear across the Plains. There will be chances for scattered thunderstorms through the period. The better chance may be across west central KS, north into NE Sunday afternoon into Sunday night. As the H5 trough moves closer to the central and southern high Plains the dryline will push farther east into central KS and a surface cold front will move southeast into north central KS Monday afternoon. The combination of surface convergence ahead of the front and dryline should provide the CWA with better chance for thunderstorms. The effective shear will be strong along with MLCAPES in the 2000-3000 J/kg range may provide an environment for supercell thunderstorms, with all hazards possible. If the front pushes faster to the southeast, then the linear convergence may be more favorable for a line of severe thunderstorms, where damaging wind gusts would be the primary hazard.

The front will push southeast of the area Monday night, that should bring an end to any strong to severe thunderstorms. The H5 trough in the southwest will begin to fill and shear out. The elevated showers and thunderstorms will continue as DCVA ahead of the H5 trough continues to overspread the CWA. There may be some beneficial rainfall on Monday with occasional elevated thunderstorms that do not look to be severe. The rain and elevated thunderstorms should shift east of the area Tuesday evening. Highs on Tuesday will be cooler with periods of rain and northerly winds, with highs in the lower to mid 70s.

The GFS and Canadian models are faster moving the front southeast of the CWA by Sunday evening and do not show the stronger forcing for post frontal showers and elevated thunderstorms northwest of the front on Tuesday like the ECMWF solution.

It will be best to keep updated on the severe weather risks this weekend into Monday.

Tuesday night through Wednesday:

A surface ridge of high pressure will move southeast across eastern KS. An H5 ridge will amply across the high Plains as the sheared out southwest H5 trough lift northeast across NE and phases with another H5 trough digging southeast across the Great Lakes. Highs Wednesday will reach into the upper 70s to lower 80s

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 618 AM CDT Wed May 13 2026

Expect VFR conditions through the next 24 hours. light northeast winds will gradually back to the east and southeast Tonight. Wind speeds will be under 10 KTS. Scattered mid level clouds will may move over the terminals towards 12Z TUE. There may also be a few showers and isolated thunderstorms towards 12Z TUE.

CLIMATE

Issued at 340 AM CDT Tue May 12 2026

Record High Temperature for May 15

Record (Year) Forecast Topeka 95 (1944) 93 Concordia 91 (1944, 2012) 94

Record High Temperature for May 16

Record (Year) Forecast Topeka 95 (1931) 90 Concordia 93 (2019) 93

TOP WATCHES/WARNINGS/ADVISORIES

None.