D R O U G H T I NFORMATION S TATEMENT S O U T H C ENT R A L T EXA S WFO A USTIN /SA N A NTONI O , TX

I SSUE D : M AY 27, 202 1

Summary

Figure 3, the U.S. Drought Monitor valid May 25th and May began on a wet note across the region. This was a issued on May 27th by the National Drought Mitigation continuation of a wet pattern that developed during the final Center, showed Abnormally Dry (D0) to Moderate drought days of April. South-Central Texas finally saw wide-spread (D1) conditions across the region. If we continue to see rainfall with amounts from one-half inch to two inches across more rainfall drought conditions will continue to improve. the west to 10-15 inches across portions of the Coastal Plains. Currently 42 percent of South-Central Texas has This rain really put a dent in the drought conditions that have Abnormally Dry (D0) conditions to Moderate drought (D1) prevailed since last year, especially across the western areas. conditions. Lakes and reservoirs have even shown increases. Due to the wetter conditions and the prospect of June starting with another wet period, this drought statement will not be issued again until conditions warrant.

Figure 1 - Total Observed Rainfall January 1, 2021 to May 27, 2021

Figure 3 – May 27th U.S. Drought Monitor County Level

The U.S. Drought Monitor is a comprehensive drought monitoring effort between government and academic partners. It is issued each Thursday morning and

incorporates hydrometeorological data through 7 AM Tuesday. Figure 2 – Departure from Normal Rainfall January 1, 2021 to May 27, 2021

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Hydrologic Impacts Fire Danger Impacts

According to the USGS Current Water Data the Pecos River As of May 28th, there were 9 counties with county-wide burn basin reported much below normal seven-day flows. The Frio b ans in effect. These burn bans are established by county and upper Guadalupe River basins reported below normal officials. seven-day flows. The Nueces, Medina, San Antonio, middle Guadalupe, Brazos, San Marcos, and Blanco River basins reported normal seven-day flows. The Colorado river basin reported above normal seven-day flows. Data for the Rio Grande and Devils basin were not available.

Reservoir conditions as of May 28, 2021 are presented in the following table.

Pool Current Reservoir Elevation Elevation (ft) (ft) Amistad 1117.00 1067.3 Medina Lake 1064.2 1027.1 Canyon Lake 909.00 904.4 Granger Lake 504.00 505.4 Georgetown Lake 791.00 782.2 Figure 5 - Burn Bans Currently in Effect Lake Buchanan 1020.00 1014.0 Lake LBJ 825.00 824.6 The Texas Forest Service uses the Keetch-Byram Drought Index (KBDI) as a system for relating current and recent Lake Marble Falls 738.00 736.3 weather conditions to potential or expected fire behavior. It is Lake Travis 681.00 660.5 a numerical index calculated daily for each county. Each Lake Austin 492.9 492.0 number is an estimate of the amount of rain, in hundredths of an inch, needed to bring the soil back to saturation. The index ranges from 0 to 800, with 0 representing a saturated soil and According to Texas Commission on Environmental Quality 800 a completely dry soil. As shown below, the May 28th (TCEQ), there are 1107 public water supply systems with issuance of the KBDI showed values of zero to 600 across voluntary or mandatory water use restrictions across the the region. entire state. Figure 4 shows the locations of affected systems across Texas. This assessment is normally updated weekly.

Figure 4 – Water Systems with Water Use Restrictions May 24, 2021

Figure 6 – KBDI County Averages Map 2

Agricultural Impacts Outlook The CPC Outlooks for June 2021 through August 2021 Each week, the Climate Prediction Center (CPC) analyzes the indicated slightly stronger trends for above average percent of available soil moisture as compared to normal. The te mperatures (figure 8) and equal chances for below average, May 27sth available soil moistu re ranges from 5 to 80 percent of average, or above average rainfall (figure 9) across South normal across South Central Texas. Central Texas. The next three-month outlooks are scheduled to be available on June 17, 2021.

Figure 8 – Temperature Outlook

Figure 7 – Percent Available Soil Moisture

The Crop Moisture Index monitors short term need compared to available water across major crop producing regions. This index is not used to monitor long term drought conditions. The latest Crop Moisture Index issued by the CPC on May 22nd indicated short term moisture conditions were slightly dry/favorably moist west to wet across the eastern portions of South-Central Texas.

Figure 9 – Precipitation Outlook

U.S. Seasonal Drought Outlook indicates drought conditions will improve across most of the region through August 31, 2021.

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Contact Information: Austin/San Antonio National Weather Service 2090 Airport Road New Braunfels, TX 78130 830.606.3617 Press 2

Website: http://www.weather.gov/austin/ Email: [email protected]

Drought Related Links:

Precipitation Data: http://water.weather.gov/precip/

The U.S. Drought Monitor: http://droughtmonitor.unl.edu/

USGS Stream Flow Conditions https://waterdata.usgs.gov/nwis/rt

TCEQ Map of Water Systems under Water Use Restriction https://www.tceq.texas.gov/drinkingwater/trot/location.html

The Texas Counties Burn Ban Map: http://tfsfrp.tamu.edu/wildfires/DecBan.png

The KDBI County Average Map: http://twc.tamu.edu/tfs/kbdi_daily/kbdicounty.png

CPC Soil Moisture: http://www.cpc.ncep.noaa.gov/products/Soilmst_Monitoring/US/Soilmst/Soilmst.s html

Texas AgNews: http://agnews.tamu.edu/

CPC Outlook Maps: http://www.cpc.ncep.noaa.gov/

CPC U.S. Seasonal Drought Outlook: http://www.cpc.ncep.noaa.gov/products/Drought/

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