Flower Mound climate

Flower Mound Weather in September

NOAA 1991-2020 normals for Grapevine Dam, 8.1 km from Flower Mound

Average highs run from 92°F on September 1 to 85°F on September 30, and lows from 71°F to 62°F. Normal precipitation for the month is 3.45 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 Flower Mound, in °F, with the record for each date.406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
89°F
Average low
67°F
Precipitation
3.45 in
Record high
111°FSep 4, 2000
Record low
43°FSep 30, 1984
Chance of a freeze
0%
Days of 90°F or more
16.1
Daylight
12 h 50 min to 11 h 52 min
Cloud cover
42%
Humidity
63%
Dew point
62°F
Wind
8.5 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 192°F71°F109°F 200064°F 195522%0%
Sep 292°F71°F109°F 200061°F 198722%0%
Sep 392°F71°F109°F 200060°F 197422%0%
Sep 492°F70°F111°F 200055°F 197422%0%
Sep 591°F70°F104°F 202355°F 197422%0%
Sep 691°F70°F105°F 202355°F 197422%0%
Sep 791°F70°F107°F 202360°F 197422%0%
Sep 891°F69°F110°F 202358°F 195622%0%
Sep 990°F69°F101°F 195455°F 195622%0%
Sep 1090°F69°F101°F 201455°F 202022%0%
Sep 1190°F68°F102°F 200053°F 196822%0%
Sep 1290°F68°F103°F 201155°F 195922%0%
Sep 1389°F68°F107°F 201156°F 201422%0%
Sep 1489°F67°F102°F 195354°F 196122%0%
Sep 1589°F67°F101°F 202651°F 199322%0%
Sep 1689°F67°F101°F 198053°F 197922%0%
Sep 1788°F66°F99°F 199751°F 198122%0%
Sep 1888°F66°F100°F 197547°F 198122%0%
Sep 1988°F66°F102°F 195645°F 198122%0%
Sep 2088°F65°F102°F 195346°F 197122%0%
Sep 2187°F65°F99°F 195645°F 198322%0%
Sep 2287°F65°F101°F 200545°F 198322%0%
Sep 2387°F64°F101°F 202344°F 199522%0%
Sep 2486°F64°F102°F 202349°F 198922%0%
Sep 2586°F63°F102°F 200544°F 198922%0%
Sep 2686°F63°F100°F 197749°F 200022%0%
Sep 2786°F63°F103°F 195351°F 199122%0%
Sep 2885°F62°F105°F 195344°F 199622%0%
Sep 2985°F62°F101°F 201146°F 196722%0%
Sep 3085°F62°F98°F 195343°F 198422%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Flower Mound, 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 7:03 AM, sunset 7:53 PM
September 30
sunrise 7:22 AM, sunset 7:14 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00413691 (Grapevine Dam), public domain. Records: NOAA GHCN-Daily, station USW00003927, 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.