textproduct: Topeka

KEY MESSAGES

- Dry and mild weather should persist through Memorial Day.

- An unsettled weather pattern is forecast to develop by Wednesday and into next weekend with chances showers and storms each day.

- Mild temperatures are expected into next weekend with highs in the 80s and lows around 60.

DISCUSSION

Issued at 220 PM CDT Sun May 24 2026

Split flow had developed over North America per the 19Z water vapor imagery. The northern stream was well north across Canada where a series of upper lows were noted from the Gulf of Alaska to the Hudson Bay. Then an upper level jet streak was noted over the CA Baja and into northern Mexico. This left a nearly zonal pattern across the central plains with a remnant MCV spinning over north TX. Surface obs showed weak ridging into eastern KS with a trough of low pressure from the northern high plains into the NEB panhandle.

For this afternoon and tonight, an isolated shower may develop within a relative moist axis just to the east of the surface trough. Although dewpoints over north central KS may be mixing out a little more. This could allow from some weak inhibition to persist through peak heating across north central KS. Much of the CAM output shows isolated storms developing to the west of the forecast area but struggle to hold them together long enough to make it into Republic or Cloud counties. Have kept a slight chance POP in case something manages to move into these counties. There may be a wind risk with any storm given somewhat dry low levels, but mid level lapse rates on the order of 8 C/km could help a more robust updraft produce some hail. Overall the severe risk appears to be low. By 02Z or 03Z, a stabilizing boundary layer and increasing CIN should bring an end to the storm chances. Lows tonight with mostly clear skies are expected to fall into the middle 50s for the eastern counties to the lower 60s out west. These cooler temps and weaker winds are expected to allow for some patchy fog to develop. Conditions for dense fog look less than favorable with a few mid clouds and enough of a pressure gradient to prevent calm winds.

There is good consensus among the operational models through Thursday and low spreads in the ensemble data. This leads to better confidence in the forecast through the week. Models show relative high pressure in the mid levels Monday with general subsidence across the forecast area. This should provide mostly sunny skies and dry conditions to persist while highs warm into the middle 80s. For Tuesday through Friday, the pattern is one we typically see more in the late July and August time frame with a muddled ridge over the central U.S. and weak mid level flow. Models forecast a conditionally unstable airmass with reasonable low level moisture as weak disturbances move within the ridge. This pattern favors more diurnally driven precip chances where heating destabilizes the airmass and precip develops in the late afternoon and evening time frame, and this is what the NBM shows. The one change to the forecast was to increase POPs across east central KS Tuesday afternoon. There is a good signal for the MCV over north TX to lift north along the KS/MO state line Tuesday afternoon. The NBM had backed off on POPs lowering them to around 5 percent. But this pattern argues for POPs more in the 20 to 30 percent range and the forecast has been adjusted accordingly. Widespread precip chances are expected Thursday as a more organized upper trough axis lifts north through the Great Plains, and don't see any reason to change the likely POPs from the NBM.

Spread starts to increase in the ensembles for Friday and next weekend as differences in the evolution of the upper trough over New England start to show up. The main implication for the forecast is whether a back door cold front will move in as the GFS shows or if we remain more under the influence of the upper ridge and the conditionally unstable airmass as the ECMWF shows. The blend seems to maintain a persistence forecast with chances for rain and highs remaining in the 80s. But the hedge is the precip chances in general are lower. Ensembles show spreads between the twenty fifth and seventy fifth percentiles of 10 degrees or more for next weekend. So with the NBM being a middle of the road forecast, adjustments are likely once a common solution becomes apparent.

AVIATION /18Z TAFS THROUGH 18Z MONDAY/

Issued at 1203 PM CDT Sun May 24 2026

RAP forecast soundings suggest the boundary layer could decouple enough for some ground fog to develop at TOP and possibly FOE. A little more mixing at MHK should lower the probability for the formation of fog. Confidence is best for some fog at TOP and will include a TEMPO group for a few hours before sunrise. Otherwise VFR conditions are forecast to prevail with a few mid level clouds.

TOP WATCHES/WARNINGS/ADVISORIES

None.