* Drought affects 1 million square miles
* Severe heat just one part of climatic problem
By Wendell Marsh
WASHINGTON Aug 5 (Reuters) - The nation’s triple-digit heatwave — which hit its 34th day on Friday — could last until the end of August, while extensive drought in and around Texas may last into October, forecasters said.
The deadly heat event that has broken numerous records has left the southern Plains and Mississippi Valley struggling to meet demand for power and water and has caused billions of dollars in damage to crops and livestock.
“Many more days of triple-digit heat are on deck as iron-clad high pressure at most levels of the atmosphere continues to squat over the south-central U.S.,” AccuWeather.com’s senior meteorologist Alex Sosnowski said.
The severe heat is just one part of a compounded climatic problem, an expert from the National Weather Service said.
Last year’s La Nina, the weather event that left equatorial sea surface temperatures in the central Pacific 2 to 4 degrees Fahrenheit cooler, triggered this year’s exceptional drought.
Normally, La Nina causes a 10 percent drop in precipitation.
Since January, the state of Texas, where the drought is anchored, has only had 40 percent of normal rain fall, NWS climate specialist Victor Murphy said.
Drought now affects over a million square miles of the lower 48 states, or 32 percent, according to the Weather Channel. The most extreme cases of “exceptional” drought stretch from Arizona to Louisiana and parts of Georgia, covering almost 11 percent of the lower 48 states.
The resulting lack of ground moisture prevents clouds from developing in the low-level atmosphere, making daytime showers near impossible.
That problem combined with a persistent dome of high pressure, the climatic conditions are not likely to change. (Editing by Jerry Norton and Lisa Shumaker)