Texas Drought Jumps to 77% as 110-Degree Heat Threatens Southern Plains Records

Q: How exactly does a massive cloud of Saharan dust manage to choke off South Florida's much-needed cooling thunderstorms?

A Saharan dust plume suppresses South Florida thunderstorms mainly because it arrives as the Saharan Air Layer, a deep mass of very warm, very dry, dusty air that makes the atmosphere more stable. South Florida’s usual summer cooling storms depend on hot, humid surface air rising quickly, often helped by the sea breeze. When Saharan air moves in, it does two things that work against that process. The dry air mixes into growing clouds and causes droplets to evaporate. That evaporation cools and weakens the updrafts before they can build into tall thunderstorm towers. At the same time, the Saharan layer is warm aloft, which acts like a “cap” or lid on the atmosphere, making it harder for surface air to keep rising. The dust itself also helps filter sunlight and creates hazy skies, but the bigger storm-killing factor is the air mass that comes with it: dryness, warmth aloft and often stronger winds. Forecasters also noted high pressure and a weaker or less effective sea-breeze setup, which further reduced the triggers that normally spark afternoon storms across South Florida. The result is fewer showers and thunderstorms, less cloud cover and less rain-cooled air. With the normal afternoon storm relief choked off, more sunshine reaches the ground, heat builds longer into the day, and temperatures and heat indices climb faster. That is why Saharan dust outbreaks are often linked not just to hazy sunsets, but to hotter, drier and more oppressive conditions in Florida.

3 articles · Updated · Fox Weather · Aug 23

77% of Texas is now in drought—up 20 percentage points in a week—as triple-digit heat tightens across Texas and Oklahoma with little relief ahead.
100-110 degree highs are forecast through at least Tuesday, threatening daily records in Dallas, Austin, Oklahoma City and Albuquerque, while humidity pushes feels-like temperatures above 110 for millions.
Dallas has already hit 105 degrees for five straight days, and Dallas, San Antonio and Waco have yet to record any August rain, marking the driest start to the month on record in all three cities.
Little to no rain is expected over the next seven days, and long-range forecasts favor above-average September temperatures across the Southwest and Southern Plains.