Area Forecast Discussion
Issued by NWS Topeka, KS
Issued by NWS Topeka, KS
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976 FXUS63 KTOP 312345 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 645 PM CDT Fri May 31 2024 .KEY MESSAGES... - Scattered rain and isolated storms continue this afternoon before tapering off this evening and overnight. - Off and on rain/storm chances remain in the forecast through early Wednesday mostly with nocturnal convection working east into the area. && .DISCUSSION... Issued at 247 PM CDT Fri May 31 2024 19Z water vapor imagery and VAD wind profilers show our MCV continuing to slowly move east across the area, while broader cyclonic flow is evident across much of Canada and the northern CONUS. At the surface, a weak boundary can be seen in central NE/KS providing enough lift for a line of weak thunderstorms. The light rain currently in our eastern counties should eventually move off to the east into this evening as the MCV pushes east and low-level subsidence takes over. The convection in north central KS should move eastward as well, though it`s expected to weaken as it does so, as instability decreases with eastern extent. Overall, this should lead to scattered showers and a few thunderstorms gradually coming to an end through the evening hours. As sfc high pressure slides south from NE and through the area tonight, quiet conditions are expected. One thing of note that`s worth monitoring is that some guidance is suggesting potential for fog overnight and especially around sunrise. Am not particularly confident that this would be impactful and soundings seem to suggest this would be more of a stratus situation, but am not willing to completely dismiss the fog given the subsidence behind the exiting system, light winds, and lingering moisture. Saturday looks mainly dry until the evening and overnight hours. The overall pattern this weekend into early next week looks like mainly zonal flow with weak perturbations providing opportunities for late night/overnight convection as these storm systems move east into our area. Saturday night brings the first of these with storms progged to develop in western/central KS late afternoon before moving eastward. Our western counties late Saturday could see MUCAPE of 1000-1500 J/kg with enough shear to support marginally severe storms if they track into our area. Early CAM guidance suggests storms may track along the instability gradient along the southwest edge of the CWA. There are some differences between models on how soon any storms move out Sunday morning or afternoon, but there should be some dry time before the next disturbance brings another complex of storms Sunday night into Monday. Depending on how much time the atmosphere has to recover, this batch of storms may have more instability to work with and could bring stronger storms over a wider area. That said, each wave will have some impact on the next one, so predictability on the finer details in this type of scenario is low. The more substantial upper trough looks to potentially impact the area Tuesday into early Wednesday as it digs over the northern Plains. This could bring storms along a cold front during this time frame, although the better upper support looks to be north of the area as of now. Cluster analysis has some variability in the ensembles on how deep this upper trough will get, which will have implications on whether sufficient upper forcing can get this far south. Longer range guidance is hinting at upper ridging developing over the southwestern CONUS, which would support rising heights with increasing temperatures into the middle of next week. Given the uncertainties leading up to that time, however, there are also some variations in timing and strength of that developing ridge. For now, highs in the 80s are forecast for much of next week with lows in the 60s. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 629 PM CDT Fri May 31 2024 MVFR conditions are likely to become IFR overnight with a lower cloud deck and likely also some reduced visibilities. The extent of fog development remains somewhat uncertain, but forecast confidence is high enough to at least introduce lower visibilities tonight and early Saturday. VFR should return as ceilings lift and scatter by midday Saturday. && .TOP WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Picha AVIATION...Teefey