NOAA Atlas 14 (PFDS)
Gov-Public
The US precipitation-frequency standard — point rainfall depths for any duration and return period, free.
Data, Monitoring & ForecastingActiveIDF CurvesRainfall Data
7 tools · Collection
Design Rainfall & IDF Toolkit
Every drainage calculation starts with a rainfall number, and getting a defensible one is its own small discipline: official IDF sources (NOAA Atlas 14 in the US, the ARR Data Hub in Australia), statistical tools for gauge records (NetSTORM), radar rainfall processing (wradlib, the NOAA Weather and Climate Toolkit), reanalysis when gauges are sparse (cdsapi/ERA5), and climate adjustment before the design leaves the ground (SWMM-CAT). This collection walks that chain end to end.
ARR Data Hub
Gov-Public
The official portal for Australian Rainfall & Runoff design inputs — losses, temporal patterns and preburst.
Data, Monitoring & ForecastingActiveIDF CurvesDesign Storms
NetSTORM
Free
CDM Smith's free rainfall statistics and STORM-method screening model — IDF analysis, disaggregation, CSO planning.
Urban Stormwater & InfrastructureActiveIDF CurvesRainfall Data
wradlib
Open Source
The open library for weather-radar rainfall processing — from raw volumes to engineering-ready rainfall fields.
Data, Monitoring & ForecastingActiveRainfall DataRemote Sensing
NOAA Weather and Climate Toolkit
Gov-Public
Free viewer and exporter for NEXRAD radar, satellite and climate data — out to GeoTIFF, Shapefile and NetCDF.
Data, Monitoring & ForecastingStableRainfall DataRemote Sensing
Programmatic access to ERA5 and the Copernicus Climate Data Store — the world's reanalysis workhorse.
Climate & Change AnalysisActiveClimate ProjectionsRainfall Data
SWMM-CAT
Gov-Public
EPA's Climate Adjustment Tool for SWMM — apply downscaled climate projections to rainfall and evaporation inputs.
Climate & Change AnalysisStableClimate ProjectionsSWMM