833 FXUS63 KTOP 230817 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 317 AM CDT Thu May 23 2019 .SHORT TERM...(Today and tonight) Issued at 317 AM CDT Thu May 23 2019 Very little on the radar in these early morning hours of Thursday, as surface high pressure over northwest has left northeasterly winds across much of Kansas and into northern Oklahoma and the panhandles. Much higher instability air and convergence along and over this boundary continue to bring strong to severe thunderstorms across Southeast Kansas and northeastern Oklahoma. A few of these storms may skirt the far southern counties before sunrise, but coverage is expected to be sparse. Even with clouds on the increase today, highs should still rise into the upper 60s north to the middle 70s in the east. Upper low over Arizona this morning is progged to lift northward into the northern Rockies through Friday morning. Storms generate along the dryline in eastern NM and along the warm front this morning and lift into central Kansas by the late afternoon into the evening hours, then passing into eastern Kansas by Friday morning. PW values in the column still running around 2 inches, and although somewhat progressive, enough training along this line of storms to warrant the flash flood watch in place for Thursday into Friday morning for areas along and west of Manhattan where ground is already well saturated. Although main hazard from linear storms would be wind, as winds are slow to back as the convection advances eastward, will be a non-zero tornado threat more so across the western half of the CWA in the evening hours, before mean flow becomes more uniformly southerly. .LONG TERM...(Friday through Wednesday) Issued at 317 AM CDT Thu May 23 2019 For Friday through Monday, models show little change in the synoptic pattern. Southwest flow aloft is progged to continue with little change in heights. At the surface, models show a weak inverted trough over the forecast area for Friday and Saturday that eventually redevelops further west and north for Sunday and Monday. Meanwhile models show abundant moisture within the warm sector with PWs remaining near record levels for late May. This is expected to help generate more than enough instability for convection. Meanwhile the southwesterly flow is expected to maintain decent 0-6km shear of 40KT to 50KT for organized storms. So in general there is a potential for severe storms with heavy rainfall each day through the weekend. The main question is how will storms trigger since there is only subtle perturbations in the model solutions. Additionally convective outflow could impact where storm development occurs on subsequent days. So mesoscale forcing will have a big influence on the weather over the next several days. Because of this have stayed rather close to the model consensus for POPs as it become difficult to pinpoint one period with a better chance than another. As for temps, there is not much change in the airmass so persistence looks to be a good first guess. The main question with regard to temps will be whether precip persists long enough to limit warming during the day or a convective cold pool knocks lows down. In general expected highs to be around 80 or in the lower 80s with lows in the 60s. By Tuesday, another upper low is progged to move from the southwest across the central Rockies. While there remains some differences in the model solutions, there appears to be a consensus for an upper trough axis to pass through the plains and help bring a cold front through the forecast area Tuesday night. This change in the pattern is forecast to bring a break from the POPs for Wednesday as well as slightly cooler temperatures. && .AVIATION...(For the 06Z TAFS through 06Z Thursday night) Issued at 1123 PM CDT Wed May 22 2019 VFR conditions hold until around sunrise when CIGS should thicken up across the area. Have delayed the onset for showers and storms for the morning until between 16-17Z. This seems to be on track with current storm trends and position of frontal boundaries to the south of the area as well as recent model guidance. Winds remain fairly light overall mainly from the east and slowly veering through the period. As chances for storms increase, then do expect MVFR conditions to be more common. Storms that do impact the area should become more widespread by late afternoon into the evening hours as the cold front advances east into the area. && .TOP WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch until 10 AM CDT this morning for KSZ056-058- 059. Flash Flood Watch from 10 AM CDT this morning through Friday morning for KSZ008>010-020>022-034>037. && $$ SHORT TERM...67 LONG TERM...Wolters AVIATION...Drake