1997. Teale GIS Solution Group. COVERAGE DESCRIPTION: The 'PRECIPITATION' layer represents lines of equal rainfall (isohyets) based on long-term mean annual precipitation data com... Napa County (Calif.). County Of Napa.
2011. MarinMap. Precipitation data created under the recommendation of consultant Bill Vandivere for the Marin Countywide Plan. Data was digitized from "Isohyetal... San Rafael (Calif.). County Of Marin.