TZUTC: 0000   
   MSGID: 166874.weather@1:2320/105 2d873443   
   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 201956   
   QPFERD   
      
   Excessive Rainfall Discussion   
   NWS Weather Prediction Center College Park MD   
   256 PM EST Thu Nov 20 2025   
      
   Day 1   
   Valid 16Z Thu Nov 20 2025 - 12Z Fri Nov 21 2025   
      
   ...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF   
   SOUTH-CENTRAL TEXAS, INCLUDING PORTIONS OF THE CONCHO VALLEY AND   
   EDWARDS PLATEAU...   
      
   ...Texas...   
      
   16Z Update: Dynamic synoptic setup across the western half of the   
   CONUS will continue to promote a heavy rainfall threat across the   
   Southern Plains into the Ozarks. Heaviest rainfall is currently   
   located over the Lower Concho Valley and Edwards Plateau in TX   
   where the location is currently situated right in the heart of a   
   textbook coupled jet max with cores located OK and back into MX.   
   The positioning of the jet maxima allow for a broad axis of ascent   
   situated in-between the two cores leading to enhanced rainfall   
   pattern across North TX back towards the Rio Grande Valley.   
   Rainfall totals are on the order of 2-5" across the Lower Concho   
   Valley and Edwards Plateau with 2-4" over portions of the DFW   
   metro. The former is currently ongoing and will exhibit the highest   
   potential for north just flash flooding, but more considerable   
   flash flooding and accompanying impacts.   
      
   LCRA and West Texas Mesonet observational sites both confirm   
   rainfall rates reaching between 2-3"/hr in the strongest cores with   
   relatively slow cell propagation with some modest training focused   
   in-of the aforementioned zones. Convergence signal from hi-res is   
   steady within much of the CAMs in that general corridor with PWATs   
   approaching 1.7-1.9", well-above the climatological norm for mid to   
   late November. Additional totals for the area are forecast to be   
   between 1-3" with locally as high as 5" in a few pockets before the   
   setup finally shifts east-northeast with the final shortwave   
   ejection anticipated later today. Considering the multitude of   
   impacts ongoing and expected rainfall prospects through at least   
   this afternoon, the previous MDT risk was shifted north to   
   encompass those zones within the Lower Concho Valley into the   
   Edwards Plateau.   
      
   Further north towards the DFW metroplex, heavy rain this morning   
   has enhanced some regional streamflows as emphasized by the gauge   
   responses in-of the metro corridor and areas just to the south.   
   This was in conjunction with a series of heavier echoes that passed   
   through the area early this morning from a generally strong   
   shortwave perturbation that ejected northeast within the mean flow   
   downstream of the mean trough. Totals between 2-4" were seen across   
   portions of the metroplex, enough to warrant a few FFW's and   
   allowing for primed soils that will be easier to promote run off   
   potential, not even including the general urbanization factors that   
   accompany the metro. A slight lull will occur now through the next   
   few hours, but another round of moderate to heavy rainfall   
   potential with convective modes allowing will add to the already   
   saturated grounds and elevated streamflows. This setup is conducive   
   for additional flash flood prospects necessitating an upgrade to a   
   SLGT risk with high-end SLGT characteristics meaning some locally   
   significant impacts are plausible if rates between 2-3"/hr   
   materialize over the urban center directly, or over those areas   
   that were hit earlier this morning where elevated streamflows are   
   anticipated to continue. The SLGT expands the rest of central TX as   
   convergence pattern and positioning within the favorable jet   
   pattern should promote heavy rain prospects this afternoon and   
   evening before the threat pivots east as the surface pattern   
   matures and begins an occlusion phase overnight into tomorrow.   
      
   Kleebauer   
      
   ..California...   
      
   16Z Update: Changes were minimal with the D1 update as the heaviest   
   rainfall will occur across southern CA with the target located over   
   the Peninsular Range due to the aided upslope components with the   
   low-level flow expected to remain semi-perpendicular to the   
   terrain. Totals between 1-2" will be common in those higher   
   elevations between 2-5k ft MSL with some localized amounts closer   
   to 3" for areas in the San Jacinto Mtns.   
      
   Kleebauer   
      
   ..Previous Discussion..   
      
   Decided to upgrade to a Slight Risk area for portions of coastal   
   Southern California as the next area of low pressure over the   
   eastern North Pacific drops along the California coast and brings   
   another round of rainfall later today into early Friday. There has   
   been an uptick in rainfall amounts in the numerical guidance over   
   the past 24 hours but still generally under an inch...although   
   locally higher amounts could fall in terrain. Concern is that   
   antecedent conditions have been wet for the better part of a   
   week...suggesting some of area could be more sensitive to run off   
   problems even away from the highly urbanized areas.   
      
   Bann   
      
   ...New Mexico...   
      
   16Z Update: Broad negatively-tilted trough located over the Great   
   Basin will lead to an area of diffluent flow located over New   
   Mexico and far eastern AZ today. Scattered showers and   
   thunderstorms across the aforementioned areas will occur with   
   pockets of heavier rainfall plausible in the period. Antecedent   
   conditions over the two areas are worthy for possible run off   
   enhancement considering the footprint of 0.5-1.5" rainfall totals   
   already positioned over the region. Isolated flash flood chances   
   continue through the afternoon before diminishing this evening.   
   Maintained general continuity from previous forecast with a low-end   
   MRGL positioned over the southern half of NM over into far eastern   
   AZ.   
      
   Kleebauer   
      
      
   Day 2   
   Valid 12Z Fri Nov 21 2025 - 12Z Sat Nov 22 2025   
      
   ...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF   
   SOUTHEAST California AND SOUTHWEST ARIZONA...   
      
   20Z Update: Little to no changes to the previous forecasts as the   
   overall synoptic pattern maintains continuity with little run-to-   
   run variance in both the QPF presentation and evolution.=20   
      
   Kleebauer   
      
   ..Previous Discussion..   
      
   Model guidance continues to lift the Plains system northward into   
   portions of the Ohio Valley. Above normal levels of moisture being   
   transported into the region from the south and encountering an east   
   to west oriented boundary...there is still the possibility for   
   isolated areas of moderate to heavy rainfall that leads to spotty   
   problems from run- off. However...the flow aloft becomes   
   increasingly flat and confluent during the day which will reduce   
   the risk of any excessive rainfall.   
      
   In California...we will carry a Slight risk across portions of the   
   desert areas of southeast CA into southwest AZ. Lobes of vorticity   
   east of the closed low will produce periodic rounds of showers and   
   embedded thunderstorms. Instability looks pretty weak, which will=20   
   likely be a limiting factor, however some brief heavier rates are=20   
   still possible from short training segments within the deep layer=20   
   southerly flow.=20   
      
   Bann/Chenard   
      
   Day 3   
   Valid 12Z Sat Nov 22 2025 - 12Z Sun Nov 23 2025   
      
   The probability of rainfall exceeding flash flood guidance is less   
   than 5 percent.   
      
   Bann/Kleebauer   
      
      
   Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go=   
   v/qpf/94epoints.txt__;!!DZ3fjg!-GtK4wo98vgVOOhfGg4zaPn-UJWtrMkYiS4C0B51XJFv=   
   fWc6f8uCcUsJMY5E56rKS2xq6MDggnICCXuBn9JTELAMWLU$=20   
   Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go=   
   v/qpf/98epoints.txt__;!!DZ3fjg!-GtK4wo98vgVOOhfGg4zaPn-UJWtrMkYiS4C0B51XJFv=   
   fWc6f8uCcUsJMY5E56rKS2xq6MDggnICCXuBn9JTFYjZXZ0$=20   
   Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go=   
   v/qpf/99epoints.txt__;!!DZ3fjg!-GtK4wo98vgVOOhfGg4zaPn-UJWtrMkYiS4C0B51XJFv=   
   fWc6f8uCcUsJMY5E56rKS2xq6MDggnICCXuBn9JTt-15QB4$=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: 1/19 100 16/0 19/10 37 104/119 105/81 106/201 114/10 120/302   
   SEEN-BY: 123/130 128/187 129/14 142/104 153/757 7715 154/10 30 50   
   SEEN-BY: 154/110 700 201/0 203/0 218/700 840 220/10 20 30 90 221/1   
   SEEN-BY: 221/6 360 226/18 30 44 50 227/114 229/110 206 300 307 317   
   SEEN-BY: 229/400 426 428 470 664 700 705 240/5832 266/512 280/5003   
   SEEN-BY: 291/111 301/1 320/119 219 319 2119 322/757 762 326/101 335/364   
   SEEN-BY: 341/66 342/200 396/45 423/81 460/58 633/280 712/848 902/26   
   SEEN-BY: 2320/0 105 304 3634/12 5020/400 5075/35   
   PATH: 2320/105 154/10 221/6 1 320/219 229/426