Antecedent conditions
Pre-event wetness (soil moisture, groundwater, storage) controlling how much rainfall becomes runoff.
Example Usage
"Antecedent wetness was high, so lower rainfall totals still caused flooding."
Typical Units & Data
Indices (API/SMD), groundwater level
Related Keywords
Related Terms
Catchment (drainage basin)
Area of land draining to a common point (gauge, outfall, confluence), defining the runoff contributing area..
Catchment Hydrology & RainfallRunoff
Portion of rainfall that becomes flow reaching drains/rivers; depends on soils, land cover and wetness..
Catchment Hydrology & RainfallRainfall intensity
Rate of rainfall over time; key driver for pluvial and flash flooding..
Catchment Hydrology & RainfallHydrograph
Time series of flow (or level) showing rise, peak and recession during an event..
Risk, Governance & ResilienceFlood hazard
The likelihood and physical characteristics of flooding at a location (extent, depth, velocity), without considering impacts..
Risk, Governance & ResilienceFlood risk
Flood hazard combined with the potential for harm to people, assets, operations or the environment..
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