Drought Watch --
USGS State Information on Drought
Map of below normal 7-day average streamflow compared to historical streamflow for the day of the year
Explanation - Percentile classes
New low
< 5
6 - 9
10 - 24
Insufficient data for a hydrologic region
Extreme Hydrologic Drought
Severe Hydrologic Drought
Moderate Hydrologic Drought
Below Normal
This map shows the 7-day average streamflow conditions in hydrologic units of the United States and Puerto Rico for the day of year. The colors represent 7-day average streamflow percentiles based on historical streamflow for the day of the year. Thus, the map shows conditions adjusted for this time of the year. Only stations having at least 30 years of record are used. Subregions shaded gray indicate that insufficient data were available to compute a reliable 7-day average streamflow value. During winter months, this situation frequently arises due to ice effects. The data used to produce this map are provisional and have not been reviewed or edited. They may be subject to significant change.