FXUS63 KTOP 050528 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 1228 AM CDT Tue May 5 2026 .KEY MESSAGES... - A few severe storms remain possible in the pre-dawn hours today (30%), with large hail and damaging winds the main hazards. - Much cooler Tuesday and Wednesday behind cold front, with occasional periods of rain. - Gradually warming up again towards the weekend. && .DISCUSSION... Issued at 1245 PM CDT Mon May 4 2026 Broad confluent flow evident on water vapor imagery this afternoon, with one deep upper low dropping southeast over the Northern Plains while another spins just offshore California. The northern stream low is beginning to push a cold front southward through the area. As that occurs this evening, isentropic ascent will increase along and north of the boundary, allowing scattered thunderstorms to develop within the unstable airmass. Forecast soundings indicate storms will likely be a bit high-based and elevated, but in an environment of moderate CAPE (1500-2000 J/kg), moderate effective shear (~35 kts), and very steep mid-level lapse rates (8-8.5 C/km). So large hail potentially up to golf ball size looks to be the main hazard with any initially developing storm, followed by some damaging wind potential as updrafts become more numerous just along/behind the front. Much cooler air will filter in behind the front overnight. With the southern stream upper low still well to our southwest, we'll see a longer period of continued isentropic ascent atop the chilly airmass. So off and on rain chances look to continue throughout the day Tuesday and into Wednesday. Particularly if low clouds can linger throughout the day, this will keep temperatures down, with highs in the upper 50s to low 60s. The main trough axis looks to pass off to our east by Thursday, bringing in drier and sunnier conditions. This should help us begin another warming trend into the weekend ahead of our next upper trough. Details with this system are fuzzy 5-6 days out, but in generally expect another increase in rain chances as it approaches. && .AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/... Issued at 1228 AM CDT Tue May 5 2026 Can't rule out some lightning at all sites over the next several hours, but SHRA more likely with high bases limiting impacts. Have a PROB group for another round of SHRA around 15Z based on latest trends but confidence is not high. && .TOP WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Reese AVIATION...Poage