The Composite Drought Evaluator eXperiment (CoDEX) is an experimental product, produced by the Colorado Climate Center, that is designed to work as an indicator of predominant conditions within certain regions of the Intermountain West. It is a composite blend of different hydrologic indicators, which are assigned values consistent with U.S. Drought Monitor drought categories.

• Yellow: blends in a drought category (D0-D4) that is consistent with USDM depiction.
• Orange: blends worse than USDM and could be considered for degradations.
• Green: blends better than USDM and could be considered for improvements.
• White: Neither blends nor USDM show drought categories.

Data Sources:

• USDM: U.S. Drought Monitor Categories (updated weekly)
• SPI: WestWide Drought Tracker Standardized Precipitation Index (updated monthly)
• Snowpack: NRCS Mapped SNOTEL Percentiles (updated daily in season)
• Soil: VIC Soil Moisture Percentiles (updated daily)
• Streamflow: USGS 28-day Averaged HUC Map Streamflow (updated daily)
• EDDI: Evaporative Demand Drought Index Percentiles (updated weekly)
• VegDRI: eMODIS Vegetation Drought Response Index Satellite Derived Vegetation Conditions (updated weekly in season)
• Impacts: Reported to CCC staff or to Drought Impact Reporter (updated when available)

This product is experimental and is for informational purposes only. It does not dictate what the U.S. Drought Monitor may look like in the future, and may not be a major source of information for the NIDIS Intermountain West DEWS webinars either.