NetSTORM
Free
CDM Smith's free rainfall statistics and STORM-method screening model — IDF analysis, disaggregation, CSO planning.
World Rainfall Pattern Painter
ActiveFree web tool for building synthetic design-storm patterns — 560+ temporal patterns, exportable to SWMM and HMS.
- Pricing
- Free
- License
- Proprietary
- Commercial use
- Check licence
- Ecosystem
- Browser
- Platform
- Web
About World Rainfall Pattern Painter
World Rainfall Pattern Painter generates synthetic rainfall hyetographs in the browser: set a depth, duration and time step, pick from a library of over 560 temporal patterns spanning 190+ countries (including Gulf-region DDF tables and IDF lookup helpers), compare candidate patterns side by side, and export in formats ready for EPA SWMM, HEC-HMS and InfoWorks ICM.
It is a lightweight, freely accessible utility rather than an institutional product — useful for quickly producing regionally-shaped design storms and for comparing how pattern choice moves results. As always, confirm the governing local standard before a pattern goes into a compliance submission.
Where it fits in the workflow
TerrainCatchmentRainfallRunoffRoutingHydraulicsMappingReporting
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