


Area Forecast Discussion
Issued by NWS Topeka, KS
Issued by NWS Topeka, KS
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095 FXUS63 KTOP 091037 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 537 AM CDT Wed Jul 9 2025 .KEY MESSAGES... - There is a 20-30% chance for showers and storms to move towards the area from the northwest overnight tonight. Confidence in severe potential is low. - Hot weather is expected through the end of the workweek. Highs Thursday should reach the middle and upper 90s. - Better chances for showers and storms is expected for Friday. - A break from the hot weather is forecast for Saturday with highs holding in the middle 80s. && .DISCUSSION... Issued at 306 AM CDT Wed Jul 9 2025 07Z water vapor imagery showed the upper ridge still over AZ while the mean westerlies remain well north across the Canadian plains. Surface obs showed broad high pressure centered over the upper Midwest with a general southerly to southeasterly low level wind field from the southern plains into the central high plains. The forecast is of low confidence due to the nature of the environment. Models continue to show a weakly forced synoptic pattern with a conditionally unstable airmass in place. So something like modest low level convergence or a convectively induced MCV could spark showers and thunderstorms. Unfortunately these features are not well handled with the models. So have tried to put together the most likely scenario for the forecast. First off there is little or no confidence in the NAM solution which appears to continue to suffer from convective feedback in the model. Yesterday the NAM had a vort max coming out of the central high plains this morning impacting the forecast area. And much of the convection instead has been over the southern high plains. There is a small cluster of convection over south central SD that could provide a MCV for later convection. But the chances of it reaching the forecast area are a little to low to include in the forecast at this time. So started out today with a dry forecast. There has been a signal from the HRRR the past couple runs of storms developing this afternoon over the WY high plains and making a run at the forecast area overnight. The only other CAMs showing a similar idea is the two MPAS models. So have some 20 to 30 percent chance POPs in the forecast to account for this. The only other change to the forecast this morning was to add some patchy fog to low lying areas. Calm winds and clear skies may allow from some radiational fog to develop. I wouldn`t expect this to linger much past 8am. There are two frontal boundaries progged by the models that show a better signal for organized precipitation. The first boundary looks to move into the area early Friday, which is a slower trend from the blend than a couple days ago. As a result the POPs have been lowered for the daytime hours Thursday and shifted west for Thursday night. The Day2 outlook shows a slight risk for the northwest corner of the forecast area. Based on the timing of the boundary and models showing bulk shear remaining between 20 and 30KT, the risk may end staying west of the forecast area. The NAM appears to be showing it`s moist bias in boundary layer moisture and developing high CAPE values, and so I take that prog with a grain of salt. But even then surface based inhibition is progged to be increasing during the overnight period. For Friday, have stayed with the blend forecast which has POPs ranging from 40 to 60 percent. This seems reasonable at this time frame. Depending on when storms develop and how much destabilization can occur, there main be some risk for severe storms through the afternoon and evening. The second frontal boundary is progged to influence the weather on Tuesday of next week and the NBM has chance POPs for this. Outside of these two synoptic forcing mechanisms any little mesoscale feature (or lack of one) could alter the forecast. So low end POPs are spread through the forecast. Temps are forecast to heat up today and Thursday as the thermal ridge builds into central KS. Heat indices are forecast to remain below 103 Thursday afternoon with some mixing of the dewpoint temps. The heat risk and WBGT are marginal for a heat advisory as well. But it may be worth considering if temps are forecast to get a little hotter. The bright spot in the forecast is on Saturday when surface high pressure pushes the boundary and likely precip chances south. It should also bring a temporary reprieve from the 90s with highs forecast to hold in the middle 80s. && .AVIATION /12Z TAFS THROUGH 12Z THURSDAY/... Issued at 537 AM CDT Wed Jul 9 2025 Not much change to the going forecast. VFR conditions are expected to prevail. Continue to watch convection in northern NEB for signs a MCV develops that may spark storms this afternoon. Latest CAMs still struggle to generate anything, so will keep a dry forecast going. && .TOP WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Wolters AVIATION...Wolters