The climate of Austin is humid subtropical with hot summers and relatively mild Winters. Austin, the capital of Texas, is located at the junction of the Colorado River and the Balcones esearpment, separating the Texas Hill Country from the Blackland Prairies to the east. Elevations within the city vary from 400 feet to just above 1000 feet above sea level. Native trees include cedar oak, walnut, mesquite and pecan.

During winter, the area is alternately influenced by a continental regime, with winds from the north and west, and by a modified maritime regime, with south and southeast winds from the Gulf of Mexico. Mild weather pre-vails during most of the winter. Sub-freezing temperatures occur on average about 25 days each year. North winds with strong cold fronts block any moderating affects from the Gulf of Mexico, and occasionally usher in frigid conditions to central Texas. The coldest low was -2 on January 31, 1949. Although daytime highs are restrained in cloudy winters, overnight lows can be potentially higher, sometimes sparring the area from the much colder minimums that come under clear skies. In these patterns, the coolest monthly average temperatures may follow, because daytime highs are limited by the cloud cover. On sunny winter days, the temperature warms to pleasant levels, while nights are cooler. In these regimes, with colder than normal nights, the average temperature can be close to normal, because the sun moves daytime highs to much above normal. Very warm days occur when dry west winds in a mild airmass allow winter temperatures to climb to spring or summerlike levels, such as 90 December 25, 1955; 90 January 30, 1971; and 99 February 21, 1996.

Daytime temperatures in summer are hot, with highs over 90 about 80 percent or more of the time. Cool fronts may affect the area and drop overnight lows to the 50s on some occasions. In these cases, warm winds quickly return, pushing lows to the 70s in a few days. In very hot summers, the continental regime of West and North Texas can have an impact of keeping daytime highs near and above 100, especially with hot west and southwest winds. Most of the time, the moderating affects of the Gulf of Mexico limit daytime highs; however, they also add to the discomfort with higher humidity. Sometimes, when weak fronts that have lost most of their cool air properties move through the area, warmer than normal daytime highs follow, as the area is blocked from the moderating affects of the Gulf of Mexico. The highest temperature of record was 112 September 5, 2000.

Precipitation is fairly evenly distributed throughout the year with heaviest amounts occurring in May and September, primarily because of tropical cyclones that migrate out of the Gulf of Mexico, or stalled out cool fronts. Precipitation from April through September usually results from thunderstorms, with large amounts of rain falling within short periods of time. Rainfall amounts have exceeded 5 inches in several hours, causing flash floods. While thunderstorms and heavy rains may occur in all months of the year, most of the winter precipitation consists of light rain. Although snow is not a significant source of moisture, it does visit the area during some winters. Average yearly rainfall is near 32 inches. Extremes vary from 11.52 inches in 1954 to 64.68 inches in 1919.

Prevailing winds are southerly; however, in winter, northerly winds are about as frequent as those from the south. Northerly winds accompany the air masses in winter and soon shift to the south as these air masses move over the Gulf of Mexico.

Average sunshine varies from about 50 percent in the winter to near 75 percent in the summer. Stratus clouds frequently develop at night during all seasons with south and southeast winds, as Gulf moisture is lifted from the coastal plains to the higher terrain over the Balcones escarpment. On some days, these clouds do not dissapate, hanging in all day, with few or no late afternoon/early evening breaks. In the winter, these stratus clouds may be accompanied by fog and drizzle, as south and southeast wind brings Gulf moisture over the top of a cool air dome at the surface. In some years, when very cloudy conditions prevail, even if these clouds break up, mostly cloudy skies linger due to a dense high deck of cirrus caused by Pacific moisture pulled over Texas by an active subtropical jet stream.

The average occurrence of the last temperature of 32 deg. in spring is early March and the average first fall occurrence of 32 deg. is late November. The extremes vary from 31 October 26, 1924 to 32 April 9, 1914.