The California Department of Water Resources's Division of Flood Management provides this series of real-time maps representing rainfall over California and Western Nevada. The color, .gif maps, available as either large-scale or detailed regional maps, show one-hour, six-hour, or twenty-four-hour rain gage readings (in inches).

NASA has unveiled its new Multi-Spectral Drought Indexer (MSDI), improving existing technology for measuring absorption and reflection of sunlight by plants in order to make maps of unprecedented detail. The data, which come from satellites, are translated by researchers into monthly maps of vegetation color changes, thus indicating how much soil moisture is available to plants. The existing...

The National Aeronautics and Space Administration (NASA) and the National Space Development Agency (NASDA) of Japan have joined to create the Tropical Rainfall Measuring Mission (TRMM). The goal of this mission is to "monitor and study tropical rainfall and the associated release of energy that helps to power the global atmospheric circulation shaping both weather and climate around the globe."...