####018002239#### AGUS74 KWCO 211506 HMDNWC National Hydrologic Discussion - EXPERIMENTAL NWS National Water Center - Tuscaloosa AL 1015 AM CDT SUN APR 21 2024 .Synopsis... New and renewed river flooding expected in Eastern Texas and the Lower Mississippi Valley... Snowmelt induced elevated flows and river flooding in the Great Basin and Intermountain West... Potential for flooding impacts continues for Puerto Rico and the USVI... .Discussion... .Eastern Texas and the Lower Mississippi Valley... New and/or renewed minor river flooding is forecast over the next few days on some rivers, creeks, and bayous in these regions due to heavy rainfall over the past 24 hours (2 - 5", MRMS). This includes upper portions of the Trinity (TX) and Sabine (TX) rivers as well as the Sulphur River (TX), Black Cypress Bayou (TX), and upper portions of the Calcasieu (LA), Pearl (MS), and Big Black (MS) rivers. In addition to those rising waterways, portions of the Neches (TX) and Sabine (TX/LA) remain in minor to moderate flood stage. With significant rainfall not expected in these regions through day 7 (Sat), forecast crests should not be affected, and future and ongoing recessions should begin and continue, respectively, as forecast over that period. .Great Basin and Intermountain West... Elevated flows on area rivers, streams, and creeks will persist as mid to high-elevation snowpack continues to melt out. The Portneuf River at Pocatello, ID is expected to rise above moderate flood stage early this week, and the Owyhee River (NV) is forecast to slowly rise above minor flood stage over the next several days. .Puerto Rico and the USVI... The threat for isolated flooding impacts, rapid river rises, and mudslides in steep terrain will continue at least through day 6 (Fri) for Puerto Rico as a wet and unstable pattern persists. Though the convection that occurs may not be widespread each day, wet to saturated soils and elevated streamflows suggest that any rainfall that occurs could produce flooding impacts. Urban flooding impacts are also possible for the USVI over the same period. //Watson $$