Texas Climate Report: September 2021

Highlights

Texas weather this month was marked with abnormally warm temperatures and dry conditions. The month of September 2021 was the 14th warmest September in the last 127 years. The state average temperature was 78.3 degrees Farenheight which was 2.4 degrees warmer than the state average from the last 127 years. Furthermore, this month was the 11th driest September in the last 127 years with an average precipitation of 1.24”. This was 1.69” below the long term average of 2.93”. Due to the warmer temperatures and lack of rain, drought conditions across the state worsened with 61.96% of the state experiencing dry conditions or worse. The main severe weather story for this month was Hurricane Nicholas which made landfall on September 14th across the Gulf Coast of the state.

Severe Weather

Hurricane Nicholas was first denoted a tropical disturbance on September 9th. By September 12th Nicholas had been denoted a tropical storm and by September 14th Nicholas had intensified to a Category 1 Hurricane. Hurricane Nicholas recorded a max wind speed of 75 mph and had a minimum pressure of 988 mbar. On September 14th at 5:30 UTC, Nicholas made landfall in Matagorda County causing intense rainfall, storm surge, and loss of power across the northern portion of the gulf coast.

Outside of Hurricane Nicholas, Texas saw limited extreme weather across September. On September 29th, a thunderstorm brought hail with a diameter of 2.25” to Young County. One day later on September 30th, multiple thunderstorms caused quarter sized hail events in Scurry County, Jeff Davis County, Andrews County, and Nolan County.

Precipitation

The month of September was marked by dry conditions across the state. The driest areas in the state consisted of the Panhandle, Big Bend Region, across the Rio Grande River, and the northern portion of the Piney Woods and Lakes and Prairies region. The majority of these regions saw precipitation between 0.1-1”. Some counties in these regions, such as Palo Pinto, saw precipitation up to 6”, while some, such as Ector and Midland, saw precipitation less than 0.1”. Central Texas and the southern Gulf Coast saw increased precipitation averages at 1-4”. McCullough County was an anomaly in these regions recording 6” of precipitation. The northern Gulf Coast saw the most precipitation in the state at 6-14”. Galveston County saw the most extreme precipitation at 12-14” and saw the 22nd wettest September in the past 127 years. Hurricane Nicholas was the main cause of the increased precipitation for Central Texas and across the Gulf Coast.

Besides the Northern Gulf Coast where Hurricane Nicholas made landfall, the rest of the state saw negative precipitation departure compared to the normal. Most of the state saw precipitation 0.1-4.5” less than the normal. Starr County had the most extreme negative departure at 6” less, while Galveston County had the most extreme positive departure at 6” more than the normal.

Drought

61.96% of the state saw drought conditions during the month of September. 54.43% saw abnormally dry conditions, 7.26% saw moderate drought conditions, while 0.27% of the state saw severe drought conditions. The abnormally dry conditions were seen across the state but were seen heavily in the Piney Woods region, Panhandle, and along the Rio Grande river. Moderate drought conditions were seen in the Panhandle, along the Red River, and along the Rio Grande River. Severe drought conditions were seen in Carson County, Collingsworth County, and Childress County. The remaining 45.57% of the state saw no drought conditions.

When it came to drought condition changes, almost all the regions experiencing abnormally dry conditions or worse saw class 1 degradation. Counties in the Panhandle saw class 2 degradation, while Childress County and Collingsworth County saw class 3 degradation. The majority of the dry conditions in the southern tip of the Big Bend region saw no change, however, there were some areas in Brewster County, Culberson County, and Hudspeth County that saw class 1 drought improvement.

Temperature

Temperatures across the state were warmer than the normal during the month of September. The Panhandle, Big Bend Region, and across the Rio Grande River saw the highest positive departure from the normal. These regions saw temperatures 2-6 degrees Fahrenheit warmer than the normal. On the other side of the state across the Gulf Coast and up in the Piney Woods Region, temperatures saw a negative departure. These regions saw temperatures 2 degrees Fahrenheit cooler than the normal. For the remainder of the state, temperatures were 0.1-2 degrees warmer than the normal.

Physical temperatures averaged 78.3 degrees Fahrenheit across the state with the northern portion of the state having average temperatures between 75-80 degrees Fahrenheit. The southern portion of the state in the South Plains saw temperatures physically higher between 80-85 degrees Fahrenheit with the area around the Rio Grande River even higher at 85-90 degrees. Specifically, Carson County (6th), Gray County (4th), Wheeler County (7th), Armstrong County (4th), Donley County (4th), Collingsworth County (5th), Briscoe County (5th), and Childress County (5th) saw some of their warmest September temperature averages across the last 127 years.