229 FXUS64 KOUN 011706 AFDOUN Area Forecast Discussion National Weather Service Norman OK 1206 PM CDT Sat Apr 1 2023 ...New AVIATION... .SHORT TERM... (Today and tonight) Issued at 409 AM CDT Sat Apr 1 2023 A quiet and cooler day today. The surface ridge will move through the area this afternoon and early this evening with winds returning to southerly west of the ridge. The airmass will remain dry, especially out west, and when combined with an increase in southerly winds this afternoon, elevated fire weather conditions will develop in far northwestern Oklahoma again this afternoon, but nowhere near the parameter space we saw Friday. && .LONG TERM... (Sunday through Friday) Issued at 409 AM CDT Sat Apr 1 2023 We will see at least some potential for thunderstorms and severe weather over the next days, and then another potentially high-end fire weather day on Tuesday. Although low-level moisture gets pushed out into the eastern Texas gulf, the western gulf does not get cleared out with moisture lurking over south Texas. Southerly winds begin advecting moisture back up overnight Saturday night with 60s dewpoints progged up toward the Red River Valley by late Sunday afternoon. At the same time, a strong mid-level wave approaches from the west. Despite the last-minute arrival of low-level moisture, lift associated with this wave will be sufficient for shower/thunderstorm development on Sunday. High lapse rates and the returning low- level moisture will increase instability and severe storms will be possible across at least north Texas and southern Oklahoma. The mid-level wave pushes east of the area by early Sunday evening ending this round of storms. Monday has the potential for a sneaky severe weather risk, although SPC did highlight the potential in their Day 3 outlook as well. Forcing is much more subtle as there is no clear shortwave to aid in convective development, and in fact the NBM would give zero POPs despite some QPF signal from the latest GFS and Canadian models. And storm development is still in question, but the environmental parameter space across portions of southeastern Oklahoma will be problematic if any storm would develop in this environment. The marginal risk seems reasonable though given the uncertainty in storm development. Tuesday has the potential to be a multi-modal high-impact day with fire weather concerns west and some storm potential east. The latter is somewhat more uncertain as the surface front may push east of the area before severe storms develop similar to yesterday, but the fire weather concerns look likely again with strong post-frontal winds and low humidity again (minimum humidity less than 20 percent across at least the western two-thirds of the area with single digit RH values in the west). ERC (Energy Release Component) values are expected to be higher on Tuesday than they were on Friday given a few more days of dry weather. We will continue to watch trends to further define these risks over the next few days. Current SPC guidance keeps the severe weather outlook area east of the forecast area, but any slowing of the system could keep the eastern part of our forecast area in play. After the front moves through with Tuesday's system, cooler weather is expected the remainder of the week. Precipitation will be possible Thursday and Friday with moisture return and isentropic lift above the frontal surface. && .AVIATION... (18Z TAFS) Issued at 1152 AM CDT Sat Apr 1 2023 Light north winds will shift to the south late this afternoon and tonight with some high clouds. Overnight, the winds will increase, especially across the west, but still expect strengthening llj to create llws across the area after midnight. Will also see increase in low clouds late tonight from south to north with a chance for showers and thunderstorms across north Texas into southern half of Oklahoma. Some MVFR ceilings possible at that time. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 65 46 71 55 / 0 0 20 0 Hobart OK 68 44 76 47 / 0 0 20 0 Wichita Falls TX 70 46 79 52 / 0 0 50 0 Gage OK 69 46 84 45 / 0 0 0 0 Ponca City OK 65 43 76 53 / 0 0 10 0 Durant OK 69 45 72 58 / 0 0 60 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ SHORT TERM...26 LONG TERM....26 AVIATION...30