FOUS30 KWBC 171555 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 1055 AM EST Tue Feb 17 2026 Day 1 Valid 16Z Tue Feb 17 2026 - 12Z Wed Feb 18 2026 ...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF CENTRAL AND SOUTHERN CALIFORNIA... 16z update: Leading shortwave within the larger scale trough has dug into the central California helping to concentrate the low level WAA along/ahead of the cold front. The overall concentration has brought total PWats up toward .75" while increasing orthogonal onshore flow to the coastal ranges to support .33-.5" hourly rain rates. The southward progression will continue to limit overall totals to below 2.5" even within the terrain (or below freezing level along the lower slopes of the Sierra Nevada), but as noted below the antecedent upper soils are fairly saturated that slightly above average run-off is expected. Still, any flooding would likely be minor or localized and mostly affect urban settings and/or recent burn scars, initially through central CA. The broader pre-frontal WAA will intersect the Santa Lucia for a longer duration; so while rates may reach up to .5" localized totals at or above 2" are increasingly possible and more in range of a typical weak AR with 400-500 kg/m/s IVT values. Through evening, there is some hint of some increased southerly flow in the surface to boundary layer intersecting the pre-frontal plume and IVT values may reach 500+ kg/m/s, however, the intersection with terrain will be a bit more oblique maintaining or slightly reducing the deep layer moisture convergence driving the rainfall rates (still generally about .3-.5"/hr mainly after 03-06z. So all in all, there are no substantial changes to the Marginal Risk of Excessive Rainfall from north of the Bay Area through Southern California coast/coastal ranges. Gallina ~~~~Prior Discussion~~~~ A mid-level disturbance centered over the Pacific Northwest Coast will shift south and east into California today. At the surface, a cold front will propagate through the Great Basin and arrive in the Intermountain West by Wednesday morning. Scattered showers and thunderstorms are expected to spread south from the north/central California Coast to SoCal this evening. Instability will be modest, between 50-150 J/Kg MUCAPE, between 00z-12z tonight, which coincides with when the mid-level vort max will be directly overhead. Precipitable water values in the 0.5-0.75" range won't be very anomalous (1-2 stndv), however isolated pockets of efficient rain rates around 1" are possible within areas of higher instability and PWATs. Upslope enhancement along the Central California and Transverse ranges could lead to higher totals in those areas. Lower snow levels on the backside of Monday's cold frontal passage will see most of the higher mountain peaks realize higher QPF in the form of snow. Antecedent conditions from Monday's rainfall will make soils and burn scars susceptible to runoff today. Urban areas will continue to be vulnerable. HREF neighborhood probabilities show a strong signal for at least 1 inch within much of the current marginal risk area. Kebede Day 2 Valid 12Z Wed Feb 18 2026 - 12Z Thu Feb 19 2026 The probability of rainfall exceeding flash flood guidance is less than 5 percent. Kebede Day 3 Valid 12Z Thu Feb 19 2026 - 12Z Fri Feb 20 2026 The probability of rainfall exceeding flash flood guidance is less than 5 percent. Kebede Day 1 threat area: https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt Day 2 threat area: https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt Day 3 threat area: https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt