123 FXUS64 KOUN 071744 AFDOUN Area Forecast Discussion National Weather Service Norman OK 1244 PM CDT Fri Oct 7 2022 ...New AVIATION... .SHORT TERM... (Today and tonight) Issued at 327 AM CDT Fri Oct 7 2022 The great fall pattern flip begins today. Current surface and radar observations show the cold front pushing southward across central Oklahoma early this morning. The sensible impacts of the cold front will not be immediately apparent apart from a modest increase in northeasterly surface winds. The cooler air lags behind in Nebraska, and will not start to filter in until tonight and tomorrow. Thus, the primary mechanism to keep things cooler today will be postfrontal cloud cover. With easterly winds along the High Plains, considerable upslope cloudiness is expected to develop and spread eastward as it has the past few days. Consequently, expect very little daytime heating in northwestern Oklahoma, where temps will remain in the low 60s. Further to the south, across southern Oklahoma and western north Texas, cloud cover may largely be avoided altogether, with the result that highs get into the 80s. Isolated showers show up currently on radar across western Oklahoma. Little if any of that rain is reaching the ground, and that is expected to continue until the cold front comes through. A focused area of precipitation is possible later today as an east-west zone of 850 mb frontogenesis develops. This band of rain is likeliest along and north of I-40 near the border with the Texas panhandle. Accumulations today will remain light as boundary layer moisture will be on the meager side. Overnight, persistent northerly surface winds and low cloud cover will lead to largely static weather conditions. The initial band of rain may decay as the zone of frontogenesis drifts south somewhat overnight, and a brief lull in precip coverage is possible. Meister && .LONG TERM... (Saturday through Thursday) Issued at 327 AM CDT Fri Oct 7 2022 Saturday will be the coolest day in our CWA since late May as thick low-level cloud cover, continued cold advection, and rain combine to bring highs well below normal. Frontogenesis within the 850-700 mb layer will be maximized in the Texas panhandle and western Oklahoma, with many short-range models depicting a narrow band of rain somewhere in our western CWA during the day Saturday. Because of the continued cold advection and persistent rain the day before, any concerns about unsaturated boundary layers will be gone, paving the way for much-needed accumulations. This is possibly a case where there will be a sharp gradient in rainfall totals in western Oklahoma - possibly as much as the difference between 1/4 inch of rain total and 3/4 inch of rain total within the same county. Areas outside of the frontogenesis band will see the chance for rain at times in central and western Oklahoma and western north Texas, but QPFs will be lower in those regions. Highs on Saturday, as previously mentioned, will be quite cool area-wide - ranging from the mid-50s in northwest Oklahoma to the low 70s in southern Oklahoma and western north Texas. Will monitor the forecast Saturday night into Sunday for possible fog. A warm-up trend should begin on Sunday, although it will likely be cooler on Sunday than previous forecasts showed. Models now show cloud cover hanging around during the day on Sunday, as shallow cold airmasses tend to do. Rain chances will continue on Sunday as the southwestern cutoff low gradually decays and begins to slowly spin our way. This decay will initiate a strengthening of the STJ within a split-flow regime, drawing southwesterly flow aloft above us and bringing in a more classic fall rain pattern. Moisture advection beneath this southwest flow will lead to repeated chances for convection at intervals between Sunday and Wednesday. Looking ahead, another cold front is possible sometime around next Thursday, which would bring our rain chances to an end momentarily heading in to the weekend. Meister && .AVIATION... (18Z TAFS) Issued at 1231 PM CDT Fri Oct 7 2022 All terminals should remain under VFR conditions through at least 06Z. Light rain falling from a mid-level cloud deck will persist through 21Z affecting a few of our terminals across western and central Oklahoma. Next batch of SHRA may come after 06Z which could affect all of our terminals except across northcentral Oklahoma. Although expecting these showers to stay elevated, reduced visibilities below the rain may result in brief near MVFR conditions, although didn't reduce visibilities below 4SM in the PROB groups. Surface winds will remain northeasterly with gusts between 15-20kts, but becoming more light and variable toward the end of this forecast as high pressure builds in from off the Central Plains. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 49 60 51 75 / 30 30 20 20 Hobart OK 48 58 50 74 / 60 60 30 30 Wichita Falls TX 55 70 53 79 / 30 20 10 20 Gage OK 42 54 46 76 / 40 60 30 30 Ponca City OK 46 64 48 78 / 10 10 10 10 Durant OK 57 74 54 79 / 10 0 0 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ SHORT TERM...68 LONG TERM....04 AVIATION...50