587 

AGUS74 KWCO 051156

HMDNWC



National Hydrologic Discussion - EXPERIMENTAL

NWS National Water Center - Tuscaloosa AL

700 AM CDT FRI JUN 5 2026



.Update...

For the morning FHO issuance, the limited impact area from portions of  

northeast Kansas through Iowa has been trimmed mostly out of Iowa to  

account for ongoing and forecast minor to isolated moderate river flooding  

following heavy rainfall last night. Additional rainfall through the  

weekend will likely generate renewed and new flooding impacts across the  

region, although there is some uncertainty in the exact location of impacts  

as there is model disagreement in where the storms are expected to develop.



//JDP



Previous discussion as follows:



...Locally considerable flash, urban, and small stream flooding are  

possible across portions of the Central Plains into the Middle Mississippi  

Valley through Friday morning...



.Central Plains into the Middle Mississippi Valley...

A Limited flood impacts selection remains in place from portions of  

northeast Kansas through Iowa tonight into Friday morning, where locally  

considerable flash, urban, and small stream flooding are possible as  

additional rounds of intense convection develop over increasingly sensitive  

antecedent conditions. Isolated moderate river flooding is also forecast  

along the Solomon (KS) and Tarkio (MO) rivers, with crests expected Friday  

afternoon.



The primary area of concern is focused across the general four-state  

boundary region where, despite limited rainfall over the past few days, the  

hydrologic environment remains sensitive following precipitation earlier in  

the week. With top-layer soils increasingly wet, though not yet fully  

saturated, and streamflows locally elevated, additional heavy rainfall may  

quickly transition to efficient runoff, resulting in renewed rises on area  

streams and rivers. The National Water Model Short Range Forecast continues  

to indicate a broad corridor of rapid-onset flooding potential across this  

region through early tomorrow morning. Additionally, a widespread signal of  

high unit discharges and streamflow magnitudes in the 20% to 4% AEP range  

persists from near Hays (KS) through the corridor between Lincoln (NE) and  

Kansas City (MO), supporting the potential for significant hydrologic  

responses in smaller/flashier basins.



Overall, widespread rainfall totals of 2 to 4" are expected, with localized  

amounts of 5 to 6" possible where training convection develops. Repeated  

rounds of training thunderstorms will likely be the primary driver of  

higher-end rainfall totals and rapid runoff responses, increasing the  

potential for out-of-bank rises on small streams and creeks as well as  

localized urban flooding where drainage systems become overwhelmed.



Looking ahead, the flooding potential will continue through the weekend as  

multiple rounds of convection impact the region. With soils becoming  

increasingly saturated after tonight's rainfall, an additional 1 to 3" of  

rainfall may produce efficient runoff and renewed or prolonged flash  

flooding concerns. Given these conditions, the timing of the Limited  

selection on the FHO may be extended if confidence in additional flooding  

potential increases.



.Great Plains...

Isolated to scattered flash flooding will be possible across much of the  

Great Plains this week as an active convective pattern persists across the  

region. Daily scattered thunderstorms will bring periods of locally heavy  

rainfall with any highly efficient storms capable of producing immediate  

direct runoff. While confidence in the exact location of hydrologic  

responses and subsequent flooding remains low, widespread flooding is not  

expected. Instead, impacts will be limited to areas that experience the  

heaviest downpours or repeated rounds of rainfall. The isolated, low  

confidence nature of potential flooding impacts (both location and  

magnitude) precludes the inclusion of a selection on the FHO.



//Freeman



Additional National Water Center products are available at  

www.weather.gov/owp/operations







$$