August 2001 began mostly dry and hot, like most of July, and ended wet and not quit as hot. From a monthly perspective, several times in early to mid August, rainy patterns attempted for evolve only to break down quickly and go back to the dry and hot days. As the month continued, the rainy patterns finally broke loose and came on strong from the 26th to the 31st, pushing the monthly totals to well above 30 Year and All-Time Climate Normals over the Eastern Half of South Central Texas, as well as causing flash flooding. The hottest period of the month was from the 5th to the 18th, then moderated slightly the 19th to the 26th, and then more significantly the 27th to 31st with rains in the area. By months end August 2001 ended up much wetter than normal over the Eastern part of the Area and drier than normal again over the extreme West Part of the area.

The strong summer subtropical high had strong affects over South Central Texas in the first 12 days of August 2001, and even though a few weak upper level lows tried to move across the area from the east, their affects were very limited and short lived by the strong subtropical high. Late the 13th and the 14th, the strong subtropical high weakened slightly as a weather system moved across parts of the area from the north and northeast, causing widely scattered showers and thunderstorms mainly the 14th over parts of Central Texas, the Hill Country, and parts of South Central Texas. Dry and hot weather quickly returned on the 15th, followed by a return of widely scattered afternoon and evening showers and thunderstorms the 16th. Mostly sunny skies and dry conditions returned the 17th and in the day of the 18th, then an area of widely scattered showers moved over parts of the Hill Country the evening of the 18th. A weather system aloft swept across the area the 19th, helping to bring widely scattered showers and a few thunderstorms, leaving spotty rain amounts, and moderated daytime temperatures. Skies cleared in the afternoon and evening of the 19th, as this weather system moved off to the east and southeast. After the 19th, dry weather returned and although hot weather came too, it was moderated by more partly cloudy like skies versus the mostly sunny conditions earlier in the month. By August 26th, more clouds emerged, as more unstable conditions evolved in advance of a weather system aloft that moved in from the northwest, causing an upper level low to form over the area, and pushed the summer subtropical high to the west. This in turn helped another weather system coming in from the south to bring its deep tropical moisture and instability across the region, only helping to increase the odds and amounts of rain. The rainy pattern was also helped by a stagnant weather pattern aloft, where light winds were unable to carry the weather systems away. This resulted in the widespread rain event of August 26th to 31st.

In looking at August 2001 in more detail, mostly sunny, dry and hot conditions, that started July 4th and 5th and continued through July, spilled over into Early to Mid August 2001. Average sunshine for the area continued to be above normal in the early to mid part of the month, adding to the affects of the heat. After August began, isolated showers and thunderstorms began to affect the area Friday the 3rd to Sunday the 5th; however, rain amounts were very isolated and brief, and most of the area had sunny skies, dry and hot conditions. With South Central Texas well to the west of Tropical Storm Barry on Sunday the 5th and Monday the 6th, South Central Texas was affected less by the maritime influence of the Gulf of Mexico, from slightly more continental northeasterly winds in the day, resulting in very hot temperatures. This phenomena has happen before. By the 7th, a weak upper level low moved across the area from the east, resulting in isolated shower and thunderstorm activity, that was slightly greater than the previous few days, giving some rain to a few more areas over parts of the hill country and eastern half of South Central Texas; however, the rain was still isolated and brief. As the low aloft moved west on the 8th, showers became more isolated over the area, although a few isolated amounts were observed.

On the 9th, subsidence increased across the area, allowing sunny, dry and hot conditions to prevail. The sunny, hot and dry weather continued through Sunday the 12th and most of Monday the 13th. Late in the day on Monday the 13th, a weak upper level disturbance moved across Central Texas from the north and northeast. Isolated late afternoon to evening showers formed over the northern Hill Country, with the help of afternoon heating and this upper level disturbance. A Trace of rain was observed at Burnet. On Tuesday the 14th, as the upper level disturbance moved a little further south and west, widely scattered showers and thunderstorms formed over parts of Central Texas in the morning. Burnet had 0.01 inches; Austin Bergstrom 0.10 inches and Austin Mabry 0.03 inches of rain. As the afternoon arrived cloudiness increased over parts of South Central Texas and the rest of the Hill Country, where widely scattered afternoon showers and thunderstorms formed. Further north over parts of Central Texas, including the Austin Area, clouds decreased in the afternoon; however, afternoon highs were moderated to the low and mid 90s compared to highs near 100 for most of the month. Afternoon highs over parts of South Central Texas were in the mid 90s to near 100, and further west toward the Del Rio area, dry and hot weather prevailed, as highs rose to 103. On August 15th sunny and hot conditions continued with many locations reaching near and above 100 degrees.

On August 16th, widely scattered showers and thunderstorms developed over Val Verde County and parts of Llano County in the predawn hours. In the afternoon this band of showers and thunderstorms moved east over parts of the Hill Country, and then widely scattered late afternoon and evening showers and thunderstorms formed over parts of South Central Texas. Rainfall amounts were still spotty; however, a few isolated areas did get locally heavy rain. The heaviest rain amounts came with 2.75 inches at Seguin Water Plant; 1.22 inches at Kingsland Sandy Creek; 0.95 inches at Marble Falls; and 0.67 inches at Llano. Further west over Val Verde County 0.15 inches was observed at Cauthorn Ranch and 0.05 inches was observed at Pandale Crossing. Camp Wood in Real County has 0.12 inches and Rocksprings in Edwards County had 0.06 inches. Locally heavy rain fell in the evening over isolated parts of Southern Bexar County and over parts of Guadalupe County. The heaviest rainfall observed again was 2.75 inches at Seguin Water Plant. San Antonio Stinson Field picked up 0.07 inches of rain.

Mostly sunny and hot days followed the 17th and in the day of the 18th. On August 18th, Austin Mabry reached it hottest afternoon high for the year, as of August 31st, with a high of 105. On the evening of the 18th an area of widely scattered showers moved across parts of the Hill Country from the west and northwest. After midnight on the 18th to the predawn hours of Sunday the 19th, the area of widely scattered showers increased becoming scattered showers and a few thunderstorms just before and after sunrise across the Hill Country. Llano had 1.78 inches of rain from a band of showers and thunderstorms that moved over Llano and Burnet Counties. At 18 miles south of Llano 1.40 inches of rain was observed. After sunrise to the early afternoon hours, widely scattered showers moved east and left only spotty rain amounts to the eastern part of South Central Texas and parts of Central Texas. San Antonio International Airport picked up 0.16 inches of rain, and Austin Mabry had 0.15 inches of rain. A trace of rain fell at Del Rio and Austin Bergstrom International Airport. Skies cleared in the afternoon and evening, as the weather system aloft that brought the spotty rains moved to the east and southeast. Daytime highs were moderated to mostly 90s, from previous daily highs around the Century Mark. Some of the heavier rain amounts from August 19th include the following: Llano 1.78 inches; 18 miles south of Llano 1.40 inches; Spicewood 0.86 inches; Dripping Springs 0.60 inches; and 3 miles north northeast of Kerrville 0.55 inches.

On the 20th to the 25th, partly cloudy like weather prevailed, with hot days and no rain. This changed on the 26th, as a rain event formed, and widespread rains followed mainly over the Eastern Two-Thirds of South Central Texas. Although daytime highs were slow to moderate the 26th and 27th, they moderated significantly the 28th to the 31st to reach the upper 70s to the 80s in contrast to the 100 degree heat earlier in the month, although further west toward Del Rio, sparse rainfall and more sunshine kept daily highs in the 80s and 90s. The rainy weather brought occasional downpours and flooding. More unstable conditions evolved in advance of a weather system aloft that move in from the northwest late the 26th, causing an upper level low to form over the area the 27th and 28th, and pushed the summer subtropical high to the west. This in turn helped another weather system coming in from the south to bring its deep tropical moisture and instability across the region, only helping to increase the odds and amounts of rain. The rainy pattern was also helped by a stagnant weather pattern aloft, where light winds were unable to carry the weather systems away. The widespread rains brought rainy weather to the area from Monday August 27th to Friday August 31st. At Austin and San Antonio near 98 percent of the months rain fell from the 26th to the 31st, with 100 percent of the months rain at Del Rio. Rainfall amounts from the 26th to the 31st at a few locations follow: Austin Bergstrom 4.95 inches; Austin Mabry 9.30 inches; Burnet Airport 5.90 inches; Del Rio International Airport 0.35 inches; Hondo Municipal Airport 4.82 inches; New Braunfels Municipal Airport 3.86 inches; San Antonio International Airport 7.66 inches; San Antonio Stinson Field 6.28 inches; and San Marcos 4.99 inches.

The dry to wet monthly rain extremes in August 2001 is not uncommon by any means for South Central Texas in August or any other month. In early August of 1978, after a dry spell in the summer of 1978, very heavy rains flooded parts of the Texas Hill Country from the  affects of the remnants of Tropical Storm Amelia. In August 1998, after a prolonged dry spell from March 1998 to August 1998, widespread rains affected South Central Texas from the remnants of Tropical Storm Charley. An extreme flood event in the Del Rio Area in Val Verde County, left Del Rio with 20.98 inches of rain for August 1998, the wettest August and Month of Record for Del Rio. In this flood event on the weekend of the 22nd and 23rd, Del Rio had 17.04 inches of rain Saturday and Sunday, and an additional 0.80 inches in the early morning hours of Monday the 24th. Dry to wet or wet to dry extreme rain trends are not just unique to August in the area, as they have historically happened during All Months of the Year in the modified Sub-Tropical Climate that affects the region.

As of August 31st, the highest temperatures so far for 2001 and the summer of 2001 came in August for Austin and San Antonio. On Sunday, August 5th, Austin Bergstrom International Airport reached 103, and on August 18th Austin Mabry reached 105. For San Antonio International Airport the highest was 102 on August 6th. In August 2001, Del Rio reached 105 on the 6th and 15th, equal to the 105 highs on July 15 and 22. As of August 31, 2001, this was 1 degrees below the 2001 Yearly High of 106 reached June 12, 2001.