515 AWUS01 KWNH 221111 FFGMPD OKZ000-KSZ000-221630- Mesoscale Precipitation Discussion 1109 NWS Weather Prediction Center College Park MD 710 AM EDT Sat Aug 22 2026 Areas affected...Central Oklahoma...South-Central Kansas... Concerning...Heavy rainfall...Flash flooding possible Valid 221110Z - 221630Z SUMMARY...Narrow band of slow moving elevated storms with favorable orientation for possible repeating along the I-35 corridor places a few urban centers at risk of possible localized flash flooding this morning. DISCUSSION...GOES-E 10.3um and regional RADAR shows expanding line of scattered cooling tops oriented favorably along/near the I-35 corridor from south-central KS into Central OK. Tops have been cooling fairly quickly nearing -70C aligned with core of deep layer moisture but also conditionally unstable air with spine of 2000 J/kg MUCAPE and 1.5-1.75" total PWat. CIRA LPW animation of Sfc-850 and 850-700mb layers show this weakly curved arc of enhanced moisture. Low level flow is generally parallel to the band through 850mb, though 700mb westerly flow is more orthogonal to the moisture/instability axis likely convergent near the base of the elevated instability within the vertical profile to seed the scattered development. Low level southerly to south-southwesterly inflow response likely further helped to deepen the vertical depth of the cells, so given the shear though the layer; cell motions have been slow. Additionally, while the RAP shows some modest divergence aloft, animation of GOES-E WV shows a very tight anticyclonic ridge axis through western OK; likely providing greater than analyzed divergence for further vertical ascent and outflow for some weak organization and maintenance of the updrafts. So many conditional elements have come together for greater than forecast convective development this morning per Hi-Res CAM suite. While the 09z RRFS has backed off, the 06z run was more in line with this evolution and given the natural bias of the RRFS to be a bit more aggressive with convective initiation in a capped environment (relative to other CAMs, esp. the HRRR), this seems to be a solution to provide some guidance in the near-term. Given the instability, rates and 15-20kts of 700mb flow (as well as southerly 20+kts of boundary layer inflow), moisture flux is supporting 1.75-2"/hr rates. However, the weak inflow and veered profile does hint at weaker overall deep layer convergence, so updrafts are a bit narrower than ideal for repeating training. Still, the 700-400mb steering flow along the shortwave ridging in W OK, may allow for some locations for repeating, though slow cell motions will likely be the best way to result in increased residency for spots of 2-4" totals. Given the recent dry conditions FFG values are higher with exception of north-central OK where 3hr values are 2-2.5" compared to 3-4"+ further south. Still, the placement of the line is nearly directly along I-35 and places larger urban centers in proximity from Wichita to Ponca City/Stillwater into the Edmond/OKC/Norman areas. So, if ideal training/repeating can align, these will be the areas of greatest localized flash flooding potential this morning. Gallina ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...ICT...OUN...TSA... ATTN...RFC...TUA...NWC... LAT...LON 38439827 38119752 36419658 35169636 34199677 33989742 34339778 35449759 36679785 37479818 38149842