Subj : HVYRAIN: Excessive Rainfa To : All From : Mike Powell Date : Fri Jan 23 2026 09:15:08 FOUS30 KWBC 230810 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 310 AM EST Fri Jan 23 2026 Day 1 Valid 12Z Fri Jan 23 2026 - 12Z Sat Jan 24 2026 ....THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS THE TEXAS HILL COUNTRY... Maintained low-end/5% probabilities for a conditional flash flood risk across the Hill Country today and tonight. 00Z models are suggestive of convection anchoring along an Arctic front - perhaps becoming slightly elevated while training/repeating across localized areas. This scenario is conditional on the eventual location of the Arctic front moving south across the region though, with some lingering uncertainty present given the tendency for strong fronts like these to outpace guidance and move farther south than anticipated. Thus, flash flood potential is conditional as well. High-res guidance hints at a complex that grows upscale while migrating east toward the Austin/San Antonio areas late in the forecast period. Cook Day 2 Valid 12Z Sat Jan 24 2026 - 12Z Sun Jan 25 2026 ....THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS THE UPPER TEXAS GULF COAST AND VICINITY... Maintained 5%/Marginal risk probabilities although with a southward shift/confined to areas near Victoria, Houston, and Lake Charles. Any chance of deep convection will reside near these areas during the forecast period and migrate west to east during the first half of the forecast period (through 00Z Sun). Lingering uncertainty remains regarding the eventual progress of an Arctic front that should eventually reach (or even move south of) the I-10 corridor during the forecast period. If that front moves south faster than guidance suggests, any deep convective threats will potentially be minimized/shifted toward open Gulf waters. Upstream convective evolution (storms over the Hill Country and Austin/San Antonio areas during the Day 1 forecast period) also poses uncertainty with the forecast. Should storms materialized as currently progged, 1-2 inch/hr rain rates could occur with surface-based or slightly elevated convection given 1.25-1.75 inch PW values just south of the front. These rates could pose excessive runoff issues should they occur in sensitive and/or urban locales. Cook Day 3 Valid 12Z Sun Jan 25 2026 - 12Z Mon Jan 26 2026 ....THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS NORTHERN AND CENTRAL ALABAMA... Models are in pretty good agreement that a linear complex of deep convection will traverse the area from west to east, with a variety of solutions providing 1-3 inch rain amounts across the region. Soil moistures are slightly more moist in portions of central and northern Alabama compared to surrounding regions, and FFGs are lower (especially near populated areas). Some concern exists regarding fast storm motions (derived from point forecast soundings) and questions about northward extent of moisture return/60s F dewpoints and subsequent surface-based instability. Enough of a signal exists across model guidance to introduce low probabilities (5%) for flash flood potential in these areas, with spatial refinements to the risk expected in subsequent outlooks. Cook $$ --- SBBSecho 3.28-Linux * Origin: Capitol City Online (618:250/1) .