Abstract
Hurricanes bring heavy rain and induce catastrophic flooding. The damage
and fatalities underscore the urgency for understanding and improving
the hydrological forecasts. Here we build an integrated hydrological
framework in support of decision making, specifically for heavy rainfall
caused by tropical storms. We apply different ensemble approaches for
short-lived tropical storms (e.g., Tropical Storm Imelda) and
long-lasting and major hurricanes (e.g., Hurricane Harvey). To drive the
WRF-Hydro/National Water Model (NWM), atmospheric inputs are derived
from the dynamical ensemble prediction based on Hurricane Weather
Research and Forecasting (HWRF) for Hurricane Harvey. For short-lived
tropical storms, which do not have operational hurricane forecast from
regional dynamical models, we manually generate an ensemble forecast
from a deterministic weather forecast from the Global Forecast System
(GFS) and perturb the precipitation intensity and location according to
the new runs from the High-Resolution Rapid Refresh (HRRR). On top of
the current operational forecast from NWM, both of our approaches
generate more than 20 separate forecasts (ensemble members) to address
uncertainties in atmospheric dynamics, specifically for tropical storms
and hurricanes. We evaluate the storm track, precipitation, and
streamflow over the hurricane-prone areas of Texas. By linking ensemble
weather forecasts to hydrological forecasts, we seek to provide a more
comprehensive understanding of the underlying models and support
advanced research on flood resilience for critical infrastructures.