Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Dec 13 2022 10:02:01 AWUS01 KWNH 131001 FFGMPD TXZ000-OKZ000-131500- Mesoscale Precipitation Discussion 1156 NWS Weather Prediction Center College Park MD 501 AM EST Tue Dec 13 2022 Areas affected...Central Oklahoma...North-Central Texas... Concerning...Heavy rainfall...Flash flooding possible Valid 131000Z - 131500Z SUMMARY...Streaks of 1-2" totals in very short duration (1-1.5hr) across wetter ground conditions pose isolated low-end & urban flash flooding potential thru early morning. DISCUSSION...Regional RADAR and GOES-E 10.3um IR depict a rapidly progressing line of stronger thunderstorms advancing across Central OK and across Northwest into North-central TX. A recent uptick in convective vigor has been noted as the line of storms is starting to ingest slightly deeper sfc to boundary layer moisture. Sfc Tds into the lower to mid-60s have increased overall moisture flux into the cells and trends are for continued broadening of updrafts, particularly, those with transient supercell characteristics as noted by cell leaving Comanche county. Strong 20-25kt sfc with 50kts at 850mb with broad angle of convergence (45-60 degress) along the leading frontal zone are resulting in solid moisture loading to support efficient rainfall production even overcoming mid-level drier air to still support intense rainfall production. Hourly rates of 2-3" are likely to become possible with the strongest/broadest updrafts, however, rainfall totals will be limited by the duration at any given point. HRRR 15 min estimates of .75-1" are probably a good proxy given translation of 50-60 mph of the cells. This is likely to limit overall totals at most locations to about .5-1"; however, given broader downdrafts oriented favorably to the angle of motions, some upstream redevelopment, there could be some possibility for very streaky totals up to 2" in 1-1.5hrs.=20 These rates and potential totals are in the vicinity of exceeding 1hr FFG values. This is supported by recent moderate rainfall events over the last week have seen similar streaks of enhanced rainfall with AHPS above 200-300% of normal closer to the Red River Valley. This is confirmed by NASA SPoRT 0-40cm relative soil moisture being at or above average ranging from 40-60%; which further increases south and east along the Red River Valley. As such, flash flooding is considered possible, but is likely on the lower end of magnitude and to be isolated to those narrow streaks of enhanced totals particularly near urban centers. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!96q1AoPBLkvl0BZYobBqlrm7YKph1HopJTUAe5SLMLY3zrPOffF9q3FAv_XqP29vgFkW= tq5QZeRUZrUuW_VPeCNCJ3k$ for graphic product... ATTN...WFO...FWD...OUN...TSA... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 36029636 35979507 35519486 34799510 33229580=20 32669687 32929878 34929828 35749770=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .