Precipitation Analyses
MGS performs statistical magnitude-frequency
and spatial analyses of precipitation for use in Engineering Applications
 | Isopluvial Maps of Washington State were recently completed, under a contract with WSDOT. Gridded datasets and shape files are available for the entire state for durations of 2-hours and 24-hours for a full range of annual exceedance probabilities. |
(Analysis was performed cooperatively with Oregon Climate Service and Jim Wallis of Yale University)
The links below are high resolution images of the precipitation maps.
| Mean Annual | 24-hr 6-month |
| 2-hr 2-yr | 24-hr 2-year |
| 2-hr 10-yr | 24-hr 10-year |
| 2-hr 25-yr | 24-hr 25-year |
| 2-hr 50-yr | 24-hr 50-year |
| 2-hr 100-yr | 24-hr 100-year |
| Extended Precipitation and Evaporation Timeseries for Continuous Hydrologic Models |
Using precipitation input that is representative of the site under consideration is critical for the accurate computation of runoff and the design of stormwater facilities. Precipitation and evaporation timeseries have been assembled for most areas of western Washington and are stored in a database file accessed by MGSFlood or in an HSPF WDM file.
Download documents describing in detail development of the timeseries.
ExtendedTimeseriesReportPierceCo.pdf
ExtendedTimeseriesReportWestWash.pdf
