U.S. Drought Monitor

Drought Monitor Map
[Image: National Drought Mitigation Center]

Click on the map to view the National Drought Summary, updated every Thursday.

Drought Resources

What can we do about drought?

There are several organizations in the US that are devoted to predicting and mitigating the effects of drought:

National Drought Mitigation Center

U.S. Drought Portal

NOAA Southern Regional Climate Center

National Weather Service Climate Prediction Center

If you live in a drought affected area here are some tips for conserving water:

Water Conservation Tips

Drought in the CSWGCIN Region

Texas SPI Blend Map courtesy of the Texas State Climatologist
Data Source: Texas State Climatologist, image prepared by HARC

Drought is a natural regular feature of any regional climate, including the Central Southwest Gulf Coast Region. Drought is defined as a deficiency in normal precipitation over a protracted time period, but can be exacerbated by unusually high temperatures and winds, or unusually low levels of humidity.

Drought has a profound effect on people and the environment and although it is considered a natural disaster, the human demand for water magnifies its negative impacts. Drought can be very costly and destructive and the effects of drought are both direct (i.e. loss of crops) and indirect (higher food costs). In fact, the US spends more on drought mitigation every year than it does on any other natural disaster.

Large portions of the CSWGCIN region have undergone extreme to exceptional drought conditions over the past six months.  Several drought affected areas in central and western Texas have received only 10% of normal rainfall over the past couple months, with March 2011 producing the driest March on record. The map depicts the six month Standardized Precipitation Index (SPI) blend from the period of November 2010 through April 2011.  The SPI is created by comparing current precipitation trends against long-term trends for a given area.  The precipitation deficit or surplus (compared to the average) is then rated on an intensity scale.  Drought conditions occur when the SPI is continuously negative and reaches values of -1.0 or less.  The results show continuous and widespread drought over the state for the past six months. 

The length of a drought is very important because although short-term drought affects soil moisture on a time scale of weeks to months, other usable water resources such as groundwater, streamflow and reservoir storage can take months to years to exhibit drought effects.

Drought & Wildfire

Texas Wildfire image, courtesy of NASA (MODIS)
Texas Wildfires on April 15, 2011; courtesy of NASA (MODIS)

According to NASA, in 2011 more than 1.4 million acres in Texas have burned due to drought-induced wildfires.  The combination of extremely low rainfall, hotter than average temperatures, low humidity and high winds has caused vegetation to dry out and created optimal conditions for wildfire.  Over 800 wildfires have occurred in Texas this year, fueled by this abundance of extremely dry vegetation.  As of May 10, 2011, 208 of the 254 counties in Texas were under Burn Bans.  Images from NASA's MODIS satellite show wildfires on April 15, 2011 spread across the state. The dangerous conditions created by high temperatures and low rainfall are highlighted in the map below, showing land surface temperature anomalies for Texas for the week of April 7-14, 2011.

Drought Resources
Showing 7 Results
CollapseDrought Monitoring
Description: From the Climate Prediction Center website..."The CPC produces maps and tabular, numerical tables for the lower 48-States of the Palmer Drought Severity and Crop Moisture indices. In addition, the CPC produces maps of topsoil moisture based on United States Department of Agriculture state reports of topsoil moisture conditions. The CPC also monitors current calculated soil moisture, current month average evaporation, runoff, accumulated precipitation, and average temperature; recent anomalies and changes; climatology, and standard deviations."
Resource Type: Datasets
Resource Format: URL
Publisher: National Oceanic and Atmospheric Administration, National Weather Service, Climate Prediction Center
ExpandDrought Response : Tips for Consumers to Save Water and Money
ExpandIntroduction to Drought Indices
ExpandNational Integrated Drought Information System : U.S. Drought Portal
ExpandNorth American Drought Briefing
ExpandRangeland Drought Management for Texans, Planning : The Key To Surviving Drought
ExpandUnited States National Oceanic and Atmospheric Administration Southern Regional Climate Center
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