Quantitative Precipitation Forecast
Issued by NWS
Issued by NWS
829 FOUS30 KWBC 271930 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 230 PM EST Thu Nov 27 2025 Day 1 Valid 16Z Thu Nov 27 2025 - 12Z Fri Nov 28 2025 The probability of rainfall exceeding flash flood guidance is less than 5 percent. An instance of urban flash flooding cannot be ruled out across portions of southeastern Florida this afternoon. An approaching cold front will trigger a few outflow-driven thunderstorms that may exhibit relatively slow storm motions due to weak wind fields below 500mb. 1.6 inch PW values and 1000+ J/kg MLCAPE in the pre-frontal airmass both support robust updrafts with locally heavy rainfall. A conditional threat will exist for spotty 1 inch/hr rain rates to impact urban areas between Miami and West Palm Beach. The isolated and conditional nature of this threat precludes any introduction of probabilities/risk areas for this outlook. Cook Day 2 Valid 12Z Fri Nov 28 2025 - 12Z Sat Nov 29 2025 The probability of rainfall exceeding flash flood guidance is less than 5 percent. Chenard Day 3 Valid 12Z Sat Nov 29 2025 - 12Z Sun Nov 30 2025 ...THERE IS A MARGINAL RISK FOR EXCESSIVE RAINFALL FOR PORTIONS OF SOUTHEAST TEXAS INTO CENTRAL LOUISIANA... We were able to trim back the northern and eastern extent of the Marginal risk with this update. Showers and embedded thunderstorms will be ongoing Saturday across the region, but the intensity/coverage is generally not expected to result in a flash flood risk. However we should see an uptick in both convective coverage and intensity between 00z-06z Sunday as low level convergence increases across southeast TX. While this activity still should be rather progressive, some brief training is possible, which could locally push rainfall amounts up over 2-3" and result in a localized flash flood risk. The 12z RRFS indicates this potential, producing localized swaths over 3" Saturday night. While the RRFS appears slower with the front than the model consensus, and thus too far west with its QPF max...the idea of some brief training resulting in locally higher rainfall still holds. Thus we will continue to carry a Marginal risk, but keep it confined to southeast TX into southwest LA where the potential for higher rainfall rates is greatest. Chenard 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