Complex Climate of Texas

Texas' weather varies widely, from arid in the west to humid in the east. The huge expanse of Texas encompasses several regions with distinctly different climates: Northern Plains, Trans-Pecos Region, Texas Hill Country, Piney Woods, and South Texas. Generally speaking, the part of Texas that lies to the east of Interstate 35 is subtropical, while the portion that lies to the west of Interstate 35 is arid desert.

Texas ranks first in tornado occurrence with an average of 139 per year. Tropical cyclones can affect the state, either from the Gulf of Mexico or from an overland trajectory originating in the eastern Pacific Ocean. Those originating from the Gulf of Mexico are more likely to strike the upper Texas coast than elsewhere. Significant floods have occurred across the state throughout history, both from tropical cyclones and from stalled weather fronts.

Cold and Snow

Northern and western sections of the state average snowfall annually due to their colder average readings each winter. For one week in February 1956, a snow storm of historic proportions struck northern Texas. The maximum amount measured was 61 inches (150 cm) at Vega with Plainview receiving 24 inches (61 cm) in one day.  El Paso, in Far West Texas, received 22.4 in (57 cm) of snow during a 24-hour period December 13–14, 1987.  For central and southern sections, snowfall is considerably more unusual. In February 1895, a large area of southeastern Texas received over 12 inches (30 cm) of snow, with peak amounts near 30 inches (76 cm) at Port Arthur.  More recently around Christmas of 2004, up to 13 inches (33 cm) of snow fell along the middle coast, with the maximum occurring at Victoria.

The worst cold snap to occur statewide occurred during the last half of December in 1983. Four stations recorded their longest continuous readings at or below 32 °F (0 °C) on record. At Austin, the temperature remained at or below freezing for 139 hours.  At Abilene, the period at or below  freezing totaled 202 hours.  Lubbock saw temperatures at or below freezing for 207 hours. The Dallas-Fort Worth airport measured temperatures at or below freezing for a total of 296 consecutive hours.  Snow which fell on December 14 and 15 across northern Texas stayed on the ground until New Year's Day of 1984.

Severe Weather

Thunderstorms are very common in Texas, especially the eastern and northern portion. Texas is part of the Tornado Alley section of the country. The state experiences the most tornadoes in the Union, an average of 139 a year. These strike most frequently in North Texas and the Panhandle.  Tornadoes in Texas generally occur in April, May, and June.

Hurricanes

Texas's position at the northwestern end of the Gulf of Mexico makes it vulnerable to hurricanes. Some of the most destructive hurricanes in U.S. history have impacted Texas. A hurricane in 1875 killed approximately 400 people in Indianola, followed by another hurricane in 1886 that destroyed the town, which was at the time the most important port city in the state. This allowed Galveston to take over as the chief port city, but it was subsequently devastated by a hurricane in 1900 that killed approximately 8,000 people (possibly as many as 12,000), making it the deadliest natural disaster in U.S. history. Other devastating Texan hurricanes include the 1915 Galveston Hurricane, Hurricane Carla in 1961, Hurricane Beulah in  1967, Hurricane Alicia in 1983, Hurricane Rita in 2005, and Hurricane Ike in 2008.

The climatology of where tropical cyclone strikes are most likely within the state appears to be changing. In the early 1980s, the most favored region during the previous century was the middle coast.  However, that region of the coastline has been rarely impacted since the 1960s, and a recent study indicates that the most vulnerable location to a tropical cyclone strike since 1851 is the upper coast, which has received 56 percent of all tropical cyclone landfalls, of which 66 percent originate from the Gulf of Mexico. This is in contrast with Louisiana and the lower Texan coast, where only 39 percent of the landfalls are from tropical cyclones of Gulf of Mexico origin.

Flooding

The most serious threat from tropical cyclones for Texans is from flooding. The worst aspect about tropical cyclones is that the weaker they are, the more efficient they can be at producing heavy rains and catastrophic flooding. Systems with sprawling circulations, such as Hurricane Beulah, also tend to make good rainmakers.  Slow moving systems, such as Tropical Storm Amelia (1978) and Hurricane Harvey (2017) can produce significant rainfall.  Tropical cyclones from the eastern Pacific and Atlantic Basins can impact the Lone Star State.  In general, flooding across Texas is more common during the spring and early autumn months, and it can also be due to nearby stationary fronts interacting with strong upper level cyclones.  The most likely location for floods statewide is the Balcones Escarpment, an area of steep elevation gradient in central Texas at the boundary between the Edwards Plateau and the coastal plain.

Extreme Temperatures

The highest temperature ever measured in Texas was 120 °F (48.9 °C), recorded on August 12, 1936 in Seymour, during the 1936 North American Heatwave, and again on June 28, 1994 in Monahans. The lowest temperature ever measured in Texas was −23 °F (−30.6 °C), recorded on February 8, 1933 in Seminole.

                                 Climate of Texas - Wikipedia