Castle Hills climate

Castle Hills Weather in September

NOAA 1991-2020 normals for San Antonio Intl AP, 3.9 km from Castle Hills

Average highs run from 94°F on September 1 to 87°F on September 30, and lows from 73°F to 66°F. Normal precipitation for the month is 3.88 in over about 7 wet days.

September day by day

The normal high and low for each date, and the record, in °F.

Normal daily high and low temperature at Castle Hills, in °F, with the record for each date.406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
90°F
Average low
70°F
Precipitation
3.88 in
Record high
111°FSep 5, 2000
Record low
46°FSep 19, 1981
Chance of a freeze
0%
Days of 90°F or more
19.7
Daylight
12 h 44 min to 11 h 54 min
Cloud cover
48%
Humidity
67%
Dew point
65°F
Wind
8.1 mph

Every day of the month

A wet day has at least 0.01 inch of precipitation; snow means at least 0.1 inch of snowfall.

DateNormal highNormal lowRecord highRecord lowChance wetChance of snow
Sep 194°F73°F102°F 195163°F 195021%0%
Sep 293°F73°F104°F 200063°F 198721%0%
Sep 393°F73°F104°F 200061°F 197422%0%
Sep 493°F73°F109°F 200056°F 197422%0%
Sep 593°F72°F111°F 200054°F 197422%0%
Sep 692°F72°F102°F 200053°F 197422%0%
Sep 792°F72°F103°F 202356°F 197422%0%
Sep 892°F72°F104°F 202360°F 195722%0%
Sep 992°F71°F102°F 202357°F 195723%0%
Sep 1091°F71°F100°F 202357°F 202023%0%
Sep 1191°F71°F100°F 200056°F 196823%0%
Sep 1291°F71°F101°F 201156°F 196823%0%
Sep 1391°F70°F100°F 200859°F 196023%0%
Sep 1490°F70°F100°F 202662°F 195923%0%
Sep 1590°F70°F101°F 202657°F 198923%0%
Sep 1690°F70°F99°F 195457°F 199323%0%
Sep 1790°F69°F98°F 199757°F 195122%0%
Sep 1890°F69°F99°F 201952°F 196822%0%
Sep 1989°F69°F100°F 201946°F 198122%0%
Sep 2089°F69°F100°F 194751°F 198122%0%
Sep 2189°F68°F98°F 202354°F 198322%0%
Sep 2289°F68°F99°F 200546°F 198322%0%
Sep 2388°F68°F99°F 200049°F 199922%0%
Sep 2488°F67°F102°F 200551°F 194721%0%
Sep 2588°F67°F105°F 200550°F 198921%0%
Sep 2688°F67°F103°F 200547°F 197521%0%
Sep 2788°F67°F102°F 200548°F 200021%0%
Sep 2887°F66°F104°F 200547°F 196721%0%
Sep 2987°F66°F97°F 201948°F 196721%0%
Sep 3087°F66°F96°F 201947°F 198521%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Castle Hills, in percent, and of at least 0.1 inch of snowfall.05101520251102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (CDT).

September 1
sunrise 7:12 AM, sunset 7:56 PM
September 30
sunrise 7:27 AM, sunset 7:21 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USW00012921 (San Antonio Intl AP), public domain. Records: NOAA GHCN-Daily, station USW00012921, every year on file, quality-flagged values removed. Cloud, humidity, wind and sunshine: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.