textproduct: Topeka

KEY MESSAGES

- Isolated to scattered showers and thunderstorms are expected to develop again this afternoon. These will be hit or miss with most areas remaining dry.

- Highs Monday are forecast to be 95-100, leading to heat indices around 105 degrees. A Heat Advisory is posted for the entire area.

- A couple chances for showers and storms are in the forecast for Wednesday through Friday with a cool down in temperatures.

DISCUSSION

Issued at 140 PM CDT Sun Jul 19 2026

Early this morning, the water vapor satellite loop and the upper air analysis showed a broad upper level ridge axis centered over UT/CO. A low amplitude upper trough was centered across across western TX. The main upper jet extended from the Pacific Northwest and east along the Canadian/US border. An upper trough was lifting northeast across New England. A tropical system was located across the northeast Gulf, northwest of Tampa Bay.

the 17Z surface map showed a weak boundary extending from the lower MS River Valley northwest into southeast KS, then northwest into western KS. Widely scattered thunderstorms were already developing across the southern suburbs of Kansas City. The observation at KTOP was 88/77, which would place the heat index at 106 degrees. We could have had a advisory in place, given the heat indices early this afternoon but if mixing deepens and the widely scattered showers and storms develop the cloud cover and rainfall should decrease the temperatures a bit, And the deeper mixing may drop dewpoints a few more degrees. Its a bit too late for a heat advisory but be careful not to over exert yourself this afternoon with any outdoor activity.

Today through Monday night:

An inverted H5 trough extended from the weak upper low over west TX, northeast across eastern KS and western MO. The H5 inverted trough may provide enough ascent for widely scattered showers and thunderstorms to develop across much of east central KS this afternoon. So, far the PBL is not mixing as deep and previous model forecast soundings were showing. Any scattered thunderstorms that develop this afternoon may contain brief heavy rainfall and gusty winds. The thunderstorms should diminish by 00Z MON.

The H5 ridge axis will expand southeast across much of KS Monday afternoon. Synoptic scale subsidence should proven thunderstorms from developing Monday afternoon but strong surface heating with highs in the mid to upper 90s, reaching convective temperatures, could cause a few weak and shor-lived isolated showers and thunderstorms to develop in the far eastern counties of the CWA. The model guidance seems to mixing the PBL to deep, allowing for dewpoints to mix down into the mid to upper 60s. However, if we keep lower 70s dewpoints across much of the CWA, we will see heat indices in the 104 to 108 degree range. So, I will keep the heat advisory going for Monday afternoon.

Tuesday through Tuesday night:

An H5 trough across south central Can will dig southeast into the upper Midwest late Monday, then southeast across the Great Lakes and OH River Valley. This will cause a surface cold front to push southward across the CWA Tuesday morning into the early afternoon hours. There still uncertainty about the timing of the front. RAP and NAM12 are faster brining the front south of the CWA by the early afternoon hours. If these models verity, we may see 100-105 degree heat indicies across southern Coffee and southern Anderson Counties. If the front is a few hours faster, then all of the CWA will see cooler temperatures with heat indices under 100 degrees. However, if the front is slower, then the Southeast counties may see heat indices of 104-108 degrees for areas along and south of I-35. The next couple of shifts will need to monitor the speed of the front over the next several model runs. If the front is slower, the southeast counties may need a heat advisory Tuesday afternoon. Also, a slower front may provide sfc convergence for isolated showers and thunderstorms Tuesday afternoon across the southeast counties.

Wednesday through Sunday:

The extended range models are in good agreement with retrograding the H5 ridge axis southwest across western TX. The mid level flow across the Plains will become northwesterly. Embedded perturbations digging southeast across the Plains may provide enough ascent for scattered showers and thunderstorms. There may be some weak isentropic lift as the surface front begins to shift back north by Saturday. Highs will cool back into the 80s, with some upper 70s across the northern counties Thursday and Friday.

The H5 ridge axis across west TX/NM will expand northeast on Sunday into the central Plains, causing high temperatures to reach the lower to mid 90s Sunday afternoon.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1253 PM CDT Sun Jul 19 2026

Afternoon heating combined with a weak inverted upper level trough across the area may cause isolated to widely scattered thunderstorms to develop around the terminals. These storms will diminish by 00Z MON. Otherwise expect VFR conditons.

TOP WATCHES/WARNINGS/ADVISORIES

Heat Advisory from 11 AM to 9 PM CDT Monday for KSZ008-KSZ009- KSZ010-KSZ011-KSZ012-KSZ020-KSZ021-KSZ022-KSZ023-KSZ024-KSZ026- KSZ034-KSZ035-KSZ036-KSZ037-KSZ038-KSZ039-KSZ040-KSZ054-KSZ055- KSZ056-KSZ058-KSZ059.