Subj : MESO: Mesoscale Discussion 2227 To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Wed Oct 04 2023 08:44:15 ACUS11 KWNS 040844 SWOMCD SPC MCD 040843=20 OKZ000-TXZ000-041115- Mesoscale Discussion 2227 NWS Storm Prediction Center Norman OK 0343 AM CDT Wed Oct 04 2023 Areas affected...portions of the central/eastern TX Panhandle through northwestern OK. Concerning...Severe potential...Watch possible=20 Valid 040843Z - 041115Z Probability of Watch Issuance...40 percent SUMMARY...Through the remainder of the pre-dawn hours, increasing thunderstorm coverage and intensity is expected to spread across the discussion area from the TX Panhandle into northwestern OK.=20 Sporadic large hail is possible, and isolated gusts near severe limits cannot be ruled out. DISCUSSION...Surface mesoanalysis shows a cold front from central KS south-southwestward across the northwesternmost part of the main body of OK, then west-southwestward as a temporarily quasistationary boundary to a low over the northern Panhandle near DUX. The cold front continued southwestward from there to east-central NM. An outflow boundary was drawn ahead of the front across north-central/ northwestern OK, moving south-southeastward about 15 kt but decelerating, and likely to become quasistationary over north- central/northwestern OK in the next few hours. Along and ahead of the front, a narrow plume of favorable low-level moisture was evident, manifest at the surface as low-mid 60s F dewpoints.=20 Available GPS-derived data and modified RAP soundings suggest around 1.25-1.5-inch PW near ICT, gradually diminishing to around 0.75-1 inch over the north-central Panhandle. This will be maintained by a corridor of southwesterly 25-35-kt flow near 850 mb for a few more hours, diminishing after about 12Z due to the diurnal coupling cycle.=20 In the meantime, IR satellite and radar imagery indicate widely scattered young convection of varying depths, including a couple=20 thunderstorms, building in the central Panhandle roughly between AMA-HHF. This activity is growing south of the surface frontal zone, near the eastern rim of increasing large-scale ascent related to a shortwave trough over the Four Corners region, and the western part of the favorable low-level moisture field. Modified 00Z AMA RAOB and forecast soundings indicate this activity is mostly elevated above a shallow layer of diabatic, nocturnal near-surface stabilization, and should remain so as it moves east-northeastward to northeastward and interacts with the top of the outflow pool along and north of the prefrontal boundary. 25-40-kt effective- shear magnitudes and MUCAPE around 1500-2500 J/kg suggest a parameter space favorable for storm-scale rotation and large hail from the most intense cells. Given the fairly shallow nature of the near-surface stable layer, isolated strong-severe downdrafts also may reach the surface. ...Edwards/Thompson.. 10/04/2023 ....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!-55R_K1CRHdhOBznU0s1ILtvMbAgtd-SjmAeNnU4OMs-SZO3ZYCevKqElu8HOlv3dCMj_tjNR= 4brSSp2yA7KokIslBo$ for graphic product... ATTN...WFO...OUN...AMA... LAT...LON 35330017 35160136 35280187 35890197 36180170 36480005 36879864 36509788 35629863 35330017=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) .