TZUTC: 0000   
   MSGID: 166885.weather@1:2320/105 2d87c4c6   
   PID: Synchronet 3.21a-Linux master/123f2d28a Jul 12 2025 GCC 12.2.0   
   TID: SBBSecho 3.28-Linux master/123f2d28a Jul 12 2025 GCC 12.2.0   
   BBSID: CAPCITY2   
   CHRS: ASCII 1   
   FORMAT: flowed   
   AWUS01 KWNH 210612   
   FFGMPD   
   CAZ000-211210-   
      
   Mesoscale Precipitation Discussion 1238   
   NWS Weather Prediction Center College Park MD   
   112 AM EST Fri Nov 21 2025   
      
   Areas affected...coastal southern CA   
      
   Concerning...Heavy rainfall...Flash flooding possible   
      
   Valid 210611Z - 211210Z   
      
   Summary...Highly localized flash flooding will be possible from   
   slow moving showers/thunderstorms capable of producing hourly   
   rainfall up to ~1 inch. This threat will exist along portions of   
   southern CA near the coast through at least 12Z.   
      
   Discussion...GOES West water vapor imagery at 06Z showed   
   a mid-level closed low centered over the central CA coast, slowly   
   moving south. Several smaller scale vorticity maxima were observed   
   within the cyclonic flow, with one of interest located over/near   
   Santa Cruz Island. Cooling cloud tops were noted east of the   
   vorticity center, northwest of a surface low within a mesoscale   
   deformation zone. The 1009 mb low was located about 30 miles west   
   of Santa Catalina at 06Z with an occluded/cold front extending   
   southward. A weak plume of low level moisture transport was   
   located ahead of the front, parallel to the southern CA coastline   
   where a few showers have recently picked up in intensity with   
   localized training along the Orange County coast.   
      
   Weak instability up to a couple hundred J/kg was located along the   
   southern CA coast from Santa Barbara to San Diego counties as   
   noted in recent ACARS/model soundings. As the mid-level low   
   continues to translate down the CA coast, the plume of low level   
   moisture ahead of the front will push inland along with the   
   initial round of stronger showers. Later in the night, some   
   steepening of mid-level lapse rates should increase instability up   
   to about 500 J/kg along the immediate coast and closer to 1000   
   J/kg offshore. The surface low is forecast to edge closer to the   
   Los Angeles/Orange County coasts through 12Z. With this movement,   
   another round of slow moving showers and thunderstorms is expected   
   to track toward the coast from the offshore waters, with potential   
   for highly localized hourly (or sub-hourly) rainfall between 0.5   
   and about 1 inch, due to slow movement.   
      
   These spotty higher rainfall rates could result in flash flooding   
   of urban areas or other sensitive terrain.   
      
   Otto   
      
   ...Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!=   
   DZ3fjg!5hy1OjoPIczj9JA_LYobi4X_8NO48jWfR8lBVWDPe-RK1XsCwgWROEbmiMan9UUefKhF=   
   UopZquPsB1jFEV3OzPJESk4$  for graphic product...   
      
   ATTN...WFO...LOX...SGX...   
      
   ATTN...RFC...RSA...NWC...   
      
   LAT...LON   34581936 34531776 33821649 32841623 32541631=20   
               32531634 32251753 32241756 32731790 33131881=20   
               33501962 34001978=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 3.28-Linux   
    * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)   
   SEEN-BY: 4/0 19/10 88/0 90/0 93/1 104/119 105/81 106/201 114/10 120/302   
   SEEN-BY: 128/187 129/14 153/757 7715 154/10 30 50 110 700 218/700   
   SEEN-BY: 218/840 220/10 20 30 90 221/1 6 360 226/18 30 44 50 227/114   
   SEEN-BY: 229/110 206 300 307 317 400 426 428 470 664 700 705 266/512   
   SEEN-BY: 291/111 301/1 320/219 322/757 335/364 341/66 200 342/200   
   SEEN-BY: 396/45 460/58 633/280 712/848 880/1 900/0 102 106 902/0 19   
   SEEN-BY: 902/26 904/0 13 905/0 2320/0 105 304 3634/12 5019/40 5020/400   
   SEEN-BY: 5075/35   
   PATH: 2320/105 154/10 221/6 341/66 902/26 229/426