The U.S. Department of Agriculture produces weekly maps and charts displaying locations and percentages of drought-affected areas corn, soybeans, hay, cattle, and winter wheat. 

A selection of worldwide maps monitoring different aspects of vegetation health.

Climate Engine allows users to analyze and interact with climate and earth observations for decision support related to drought, water use, agricultural, wildfire, and ecology.

NOAA Center for Satellite Applications and Research (STAR) normalized difference vegetation index (NDVI) maps

The Keetch-Byram Drought Index assesses the risk of fire by representing the net effect of evapotranspiration and precipitation in producing cumulative moisture deficiency in deep duff and upper soil layers.

U.S Forest Service Cumulative Drought Severity Index (CDSI): allows users to compare the severity of droughts experienced by different forest ecosystems between two periods, 1960-1986 & 1987-2013.

VegDRI: a weekly depiction of vegetation stress across the contiguous United States.

Drought Impacts Reporter (DIR): an interactive database of drought impacts in the U.S., by location, data, type, and cost built from stakeholder, government, media and other reports.