TZUTC: 0000   
   MSGID: 168176.weather@1:2320/105 2dbed688   
   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   
   FOUS30 KWBC 020021   
   QPFERD   
      
   Excessive Rainfall Discussion   
   NWS Weather Prediction Center College Park MD   
   721 PM EST Thu Jan 1 2026   
      
   Day 1   
   Valid 01Z Fri Jan 02 2026 - 12Z Fri Jan 02 2026   
      
   The probability of rainfall exceeding flash flood guidance is less   
   than five percent.   
      
   The upper low associated with the heavy rain that fell earlier   
   across portions of California is now inland, centered over the=20   
   Sierra Nevada. In its wake, mesoanalysis shows a shortwave ridge=20   
   moving onshore, which recent runs of the RAP indicate will continue   
   to build and remain centered over the state through the remainder=20   
   of the period. Precipitation coverage has been on the decrease=20   
   across the state for the past few hours and apart from a few=20   
   isolated showers, estimated rates are under 0.25 in/hr. Isolated to   
   scattered showers are forecast to continue into the overnight;=20   
   however, the consensus of the guidance indicates that apart from a=20   
   few localized areas, most likely centered over the northern=20   
   Sacramento Valley and adjacent terrain, additional accumulations=20   
   will be under 0.5 inch.   
      
   Therefore, the previous outlook areas, including the Slight Risk   
   for Southern California, were removed.   
      
   Pereira=20   
      
   Day 2   
   Valid 12Z Fri Jan 02 2026 - 12Z Sat Jan 03 2026   
      
   ...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF   
   CALIFORNIA...   
      
   ...19z Update...   
   Only minor changes made to the inherited Marginal risk area as the   
   forecast remains on track.   
      
   Chenard   
      
   ...Previous Discussion...   
      
   An expansive upper level cutoff low over the Pacific well west of   
   the northern California coast will approach the northern California   
   coast Friday night. The occluded front wrapping around a surface   
   low will be the primary forcing for heavy rainfall into northern   
   California Friday night. The occluded front will turn the flow a   
   bit more onshore (southeast before the front to south-southwest   
   behind it). This will allow the coastal ranges to upslope some of   
   that moisture, locally enhancing rainfall rates, particularly into   
   the northern Coastal Ranges and the Klamath Mountains. Some heavy   
   rain may impact the Bay area and the coastal ranges south from   
   there in the waning couple hours of the period, assuming the timing   
   of the front moving into the coast remains unchanged. IVT values   
   between 500 and 750 kg/ms are far from impressive, and moisture   
   anomalies rise to around 2 sigma above normal, a common occurrence   
   in this part of the world, especially the past few weeks. Thus,   
   with the rainfall event just getting going, coming in in the middle   
   of the night, and with less-than-impressive dynamics, the Marginal   
   Risk for much of the central and northern California coast remains   
   largely unchanged with this update, and the Marginal looks on   
   track.   
      
   Wegman   
      
   Day 3   
   Valid 12Z Sat Jan 03 2026 - 12Z Sun Jan 04 2026   
      
   ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF   
   SOUTHERN CALIFORNIA...   
      
   ...19z Update...   
   A Slight risk was added across Santa Barbara and Ventura counties   
   in southern CA with this update. A line of locally heavy rainfall   
   rates is expected to traverse this corridor between 12z Sat and   
   00z Sun along/ahead of a cold front. Forecast rainfall amounts have   
   trended up over this area, with totals of 1-3" now expected,   
   mostly falling in ~6 hours or less. The quick duration will be a   
   limiting factor for more significant flood impacts, but with some   
   weak instability possibly working into the front and low level flow   
   aligned orthogonal to the terrain...hourly rainfall over 0.5" is   
   probable on a localized basis. Given the saturated soil over this   
   area due to recent heavy rainfall, these rates may be high enough   
   to result in isolated to scattered flash flooding, along with   
   localized mudslides and debris flows.   
      
   Chenard   
      
   ...Previous Discussion...   
      
   A series of upper level disturbances rotating around a large upper   
   level low will impact much of California and the West Coast this   
   weekend. With each upper level disturbance, there will be a   
   commensurate surface front that also makes its way ashore into   
   northern California. The result will be an almost non-stop rain,   
   especially for upslope areas on southerly flow, as well as for all   
   of the coastal ranges. That said, each disturbance will briefly   
   increase rainfall rates, with those rates decreasing back down in   
   between disturbances. Thus, Saturday's rain looks to be a long-   
   duration relatively light (for most areas) rain, rather than there   
   being big concerns on any one area seeing prolonged heavy rain.   
   Given the area's good ability to drain rainwater quickly, a   
   Marginal Risk remains in effect for northern California. The area   
   will continue to be monitored for a possible Slight Risk upgrade   
   with future updates.   
      
   Wegman   
      
      
   Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go=   
   v/qpf/94epoints.txt__;!!DZ3fjg!5_KNE7IHsqIKsygJOqkUHKfgFFDSWefA9o1jt1s4tier=   
   vHlUSO5OYXyC4SYSrxQcVERXoXPlpGwOfZrILjWGV0aS_S8$=20   
   Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go=   
   v/qpf/98epoints.txt__;!!DZ3fjg!5_KNE7IHsqIKsygJOqkUHKfgFFDSWefA9o1jt1s4tier=   
   vHlUSO5OYXyC4SYSrxQcVERXoXPlpGwOfZrILjWGK30crP4$=20   
   Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go=   
   v/qpf/99epoints.txt__;!!DZ3fjg!5_KNE7IHsqIKsygJOqkUHKfgFFDSWefA9o1jt1s4tier=   
   vHlUSO5OYXyC4SYSrxQcVERXoXPlpGwOfZrILjWGS3dl83I$=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: Capitol City Online (1:2320/105)   
   SEEN-BY: 19/10 104/119 105/81 106/201 114/10 120/302 128/187 129/14   
   SEEN-BY: 153/757 7715 154/10 30 50 110 700 218/700 840 220/10 20 30   
   SEEN-BY: 220/70 90 221/1 6 360 226/17 18 30 44 50 227/114 229/110   
   SEEN-BY: 229/134 206 275 300 307 317 400 426 428 470 664 700 705 266/512   
   SEEN-BY: 267/800 291/111 301/1 320/219 322/757 335/364 341/66 342/200   
   SEEN-BY: 396/45 460/58 633/280 712/848 770/1 100 340 350 772/210 220   
   SEEN-BY: 772/230 902/26 2320/0 105 304 3634/12 5020/400 5075/35   
   PATH: 2320/105 154/10 221/6 218/840 770/1 633/280 229/426