


Area Forecast Discussion
Issued by NWS Topeka, KS
Issued by NWS Topeka, KS
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898 FXUS63 KTOP 071046 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 546 AM CDT Mon Jul 7 2025 .KEY MESSAGES... - Scattered thunderstorms are possible from mid-afternoon through early evening today with a second round possible overnight. - The storms could be capable of damaging winds. - There is little change in the weather pattern through the week with warm and humid conditions persisting. && .DISCUSSION... Issued at 252 AM CDT Mon Jul 7 2025 Regional radar showed an MCS moving across southwestern KS at 0730Z with more isolated convection across the WY high plains. This was occurring around the northern periphery up an upper ridge over NM and as the mean westerlies remains well north of the forecast area. Surface obs showed weak high pressure over much of the central plains. Except for the cold pool from the MCS to the west, any surface boundary was becoming less defined. The weather is going to be driven by mesoscale processes more than anything. Models show a more favorable thermodynamic environment developing this afternoon with mid-level lapse rates between 6C and 7C resulting in a conditionally unstable airmass with little to no inhibition. The question is what triggers convection with no obvious surface boundary or convergence. Perhaps a remnant MCV from this morning`s convection. The 06Z RAP and 00Z NAM both show a vort max drifting across northeast KS this afternoon with QPF indicative of scattered storms. So will showing increasing chances for showers and storms through the afternoon similar to the 00Z HREF. Shear remains modest, although a little better than the past couple days with 0- 6km bulk shear around 25KT. And forecast soundings prog around 1000 J/km of downdraft CAPE. So isolated damaging wind gusts looks to be the biggest concern with the storms. The forecast keeps a 40-50 percent chance POP through the overnight period for a possible MCS moves south through NEB. There is progged to be better shortwave forcing and low level convergence to the north tonight. But some of the CAMs hint at this MCS weakening as it moves south, possibly due to the afternoon convection overturning the airmass. Confidence in the POP forecast is below average given the weak forcing and mesoscale drivers and is more of a middle of the road forecast where chances could be higher or lower depending how things unfold over the next 24 hours. There isn`t much change in airmass from yesterday so today`s forecast highs should look similar to yesterdays observed readings. There remains a chance for showers and storms Tuesday across the eastern counties. One of a couple scenarios is possible, with the morning convection weakening as it moves through leaving a weak boundary for afternoon redevelopment. Or the MCS plows through the area reducing the instability for redevelopment. Time will tell. Models show less shortwave activity coming over the upper ridge for Tuesday night through Wednesday night. So the forecast generally has a dry forecast with afternoon temps remaining around the 90 degree mark. There remains a signal for a more amplified shortwave trough bringing a surface boundary into the area Thursday night and Friday morning. So there remains some chance POPs in the forecast for this possibility. After Friday, the general consensus is for the mean westerlies to remain north of the forecast area with generally weak flow and a conditionally unstable airmass. So it is difficult to rule out chances for precip. But models do show a brief break from the heat for Saturday. && .AVIATION /12Z TAFS THROUGH 12Z TUESDAY/... Issued at 546 AM CDT Mon Jul 7 2025 Most recent runs of the HRRR continue to show TS coverage a little more isolated but still potentially impacting the terminals this afternoon. Without a surface feature to focus development, confidence in location of storms is low and will keep with the PROB30 group. Overnight several solutions continue to show a weakening trend with the potential MCS as it moves towards the terminals at the end of the forecast period. So will let later shifts take another look at this. As for the ground fog, it shouldn`t last much past 12Z as the boundary layer begins to heat up. && .TOP WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Wolters AVIATION...Wolters