Hydrometeorological Discussion
Issued by NWS
Issued by NWS
183 AGUS74 KWCO 291511 HMDNWC National Hydrologic Discussion - EXPERIMENTAL NWS National Water Center - Tuscaloosa AL 1015 AM CDT SUN JUN 29 2025 .Synopsis... River flooding to persist through at least midweek across the Central Plains and Mid to Upper Mississippi Valley... Flooding possible through midweek along the Gulf Coast... Flooding potential continues across the Mariana Islands... .Central Plains and Mid to Upper Mississippi Valley... Scattered minor to isolated moderate river flooding is ongoing and forecast across portions of MO, NE, IA, MN, and WI through at least midweek following repeated rounds of heavy rainfall over the past several days. In addition to ongoing river flooding, slow moving precipitation today, will bring the potential for flash and urban flooding as it moves across the Middle/Upper Mississippi valleys. .Gulf Coast... Periods of heavy rainfall may generate isolated flash and urban flooding impacts along the I-10 corridor from coastal MS through the FL Big Bend region through midweek. For most of the region, current soil moisture values are near normal (35 - 55% RSM, 0 - 10 cm NASA SPoRT) and streamflow values are near to below normal for this time of year (USGS), which suggests infiltration capacity initially. The exception to this is the FL Big Bend region, where wetter soils (RSM 70%, NASA SPoRT) are in place following recent rainfall, which indicates slightly greater hydrologic sensitivity to rainfall. As of now, the primary threat is urban flooding given the dense urban infrastructure along the I-10 corridor. Both the GFS and NBM-forced NWM are indicating little to no responses, as the heaviest QPF remains off of the coast. Most flooding impacts should be from isolated convection. .Mariana Islands... The potential for flash flooding will continue through tonight(local time) as monsoonal showers and storms persist across the islands. //GKendrick $$