2023 Was Hottest Year since 1895 and 33rd Driest
According to Dr. Mark Wentzel, Hydrologist for Texas Water Development Board, 2023 was the hottest and 33rd driest year for Texas since 1895. That’s 128 years!
“We began 2023 with half the area of the state impacted by drought, the result of a statewide drought that had been ongoing for more than a year,” said Wentzel. “Drought conditions improved early in the year, reaching a low of 23 percent of the state in mid-June. But conditions worsened over the summer and reached a high of 86 percent in mid-September. Conditions improved in the last quarter, and we finished the year with 39 percent of the state in drought.”
Since the start of 2024, the percentage of Texas in drought has declined to 31% and that number could drop even more next week.
Reasons for Optimism
Wentzel continued, “Impacts due to drought have varied across the state. The most impacted surface water supplies have been in Central and South Texas. But we did end 2023 with reason for optimism. El Niño conditions, warmer-than-average sea surface temperatures in the eastern Equatorial Pacific, are in place and, as a result, continued drought improvements are expected in early 2024.”
Departures from Normal
These maps show last year’s departures from normal for both temperature and precipitation. From a water supply perspective, reds, oranges, and yellows mean trouble on both maps.
They show areas with above-average temperature on the left and below-average precipitation on the right. As shown on the left, 2023 was warmer than normal everywhere in the state.
As shown on the right, precipitation was also below normal for most of the state. 2023 wound up being the 33rd driest year since 1895. Still, it was an improvement from 2022, which was the 13th driest year since 1895.
Percentage of State In Drought
The next chart shows how drought impacted the state week by week throughout the year.
At the start of 2023, 50 percent of the state was in drought. That receded to 23 percent by mid-June but expanded again to 86 percent by mid-September.
Between mid-September and the end of the year, drought receded again, falling to 39 percent in December.
As of 1/16/2024, the U.S. Drought Monitor shows that drought has declined even more from year-end levels.
Drought Impact on Water Supply
Wentzel discussed how drought impacted surface-water-supply systems across the state in 2023.
The most drought-impacted water supplies were in Central and South Texas. Water supplies for Brownsville, Laredo, Temple, Killeen, and Waco reached their lowest values in 30 years during 2023.
Conditions in Waco returned to normal in late October/early November, thanks to beneficial rains. Houston was down only 1% at year end.
As of today, both Lake Conroe and Lake Houston are down only tenths of an inch from their normal levels.
Wetter than Average Winter Predicted for 2024
According to Wentzel, from a water supply perspective, we have reason for optimism. El Niño conditions, warmer than average sea surface temperatures in the eastern Equatorial Pacific, are in place. And as a result, Winter 2024 is expected to be wetter than average. If we can maintain average precipitation through May, typically the wettest month of the year for Texas, we should see significant improvements before summer 2024.
Here Comes the Rain
Widespread and sustained heavy rainfall expected next week could alter the drought situation significantly.
Parts of the Houston Area could see up to 7 inches of rain in the next 5 days.
According to Jeff Lindner, Harris County Meteorologist, “Widespread amounts of 3-5 inches are increasingly likely over a 3-4 day period. Monday will see the start of some of the heavier rains, with some hourly rates in the 1-2 inch range if we get thunderstorms going over the area.”
Given the slow moving nature of the entire weather system, Lindner expressed concern for repeat cell training. It could enhance rainfall amounts and flood/flash-flood threats.
Lindner specifically cited several watersheds in north Harris County. Cypress Creek, Spring Creek, Little Cypress Creek, Luce Bayou, Willow Creek, the San Jacinto River basin, and Cedar Bayou tend to drain slowly, he said.
So, the cumulative effect of multiple rounds of rainfall in those watersheds can result in sustained rises over the duration of the rainfall event. However, in other watersheds, he also expressed concern about the threat from sustained heavy rainfall that can produce more rapid flooding.
Keep your eye on the sky!
Posted by Bob Rehak on 1/19/2024
2334 Days since Hurricane Harvey
