904 FXUS64 KTSA 270236 AFDTSA Area Forecast Discussion National Weather Service Tulsa OK 936 PM CDT Sat Jun 26 2021 ...UPDATE... .DISCUSSION... A very slow moving band of locally heavy rainfall, featuring training thunderstorms, has set up to the northwest of Tulsa, in an area that received 1 to 2 inches of rain earlier this morning. Radar trends indicate that the band overall is beginning to sag southward some, likely due to the interaction of a narrow band of showers and storms that briefly formed just to the north along a small outflow boundary. This trend is depicted well in recent runs of the HRRR, as well as the 3 km NAM, which indicate that the heavy rain axis is likely to shift closer to the I-44 corridor and the axis of better moisture toward midnight and into early tomorrow morning. Overall areal coverage of showers and thunderstorms is also likely to increase after midnight with a late morning/early afternoon lull again tomorrow. The primary updates to this forecast involve tweaking the highest POPs according to the above expectations and increasing QPF to the northwest of I-44 through 06Z and near the I-44 corridor and into far northwest Arkansas from 06Z to 12Z. Heavy rain wording was also added to northeast Oklahoma and far northwest Arkansas. && .PREV DISCUSSION... /Issued 617 PM CDT Sat Jun 26 2021/ AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. Ongoing scattered showers nern OK/nwrn AR expected to become more widespread later this evening as activity spreads into the area from the west and southwest. MVFR cigs/vsbys expected with TSRA activity, with best chances occurring at nern OK sites. MVFR cigs overspread much of the area late tonight, and continue through Sunday morning. Convection will probably wane across our area by late morning, similar to this morning, with another round developing during the afternoon and continuing through the evening. PREV DISCUSSION... /Issued 309 PM CDT Sat Jun 26 2021/ DISCUSSION... A lull in the rain is currently in progress, but should not last much longer. The next round of showers and storms should begin to develop within the next couple hours, and gradually organize into a larger complex of showers and storms that will affect much of northeast Oklahoma and far northwest Arkansas overnight into Sunday morning. Have expanded the flash flood watch south and east, and also extended it through Sunday. Two to four inches of rain will be possible, with locally higher amounts. The overall pattern will change little until the end of next week. A weak frontal boundary will remain in the vicinity, with an upper trough just to our west. Daily rounds of showers and storms will continue, with locally heavy rainfall possible, with mesoscale processes determining the location of heaviest rainfall on each specific day. It is likely that flood or flash flood watches will need to be extended in some places well into next week. We may finally begin to dry out some by next weekend, although some model differences exist by that time. Stayed close to the National Blend of Models forecast. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...Flash Flood Watch through Sunday evening for OKZ054>071. AR...Flash Flood Watch through Sunday evening for ARZ001-002-010-011. && $$ SHORT TERM...22