Starr County climate

Starr County Weather in September

NOAA 1991-2020 normals for Rio Grande City, 21.9 km from Starr County

Average highs run from 97°F on September 1 to 92°F on September 30, and lows from 74°F to 68°F. Normal precipitation for the month is 5.12 in over about 8 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 Starr County, in °F, with the record for each date.406080100120151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
94°F
Average low
71°F
Precipitation
5.12 in
Record high
106°FSep 24, 2005
Record low
53°FSep 30, 2020
Chance of a freeze
0%
Days of 90°F or more
25.3
Daylight
12 h 40 min to 11 h 55 min
Cloud cover
46%
Humidity
69%
Dew point
69°F
Wind
8.9 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 197°F74°F104°F 202671°F 200822%0%
Sep 297°F74°F104°F 201870°F 202323%0%
Sep 396°F74°F105°F 201168°F 200623%0%
Sep 496°F73°F105°F 202669°F 200623%0%
Sep 596°F73°F104°F 202669°F 200623%0%
Sep 696°F73°F104°F 202660°F 201123%0%
Sep 795°F73°F104°F 202367°F 201724%0%
Sep 895°F73°F105°F 202361°F 201124%0%
Sep 995°F73°F103°F 202365°F 201124%0%
Sep 1095°F72°F105°F 202364°F 201724%0%
Sep 1195°F72°F105°F 202663°F 201724%0%
Sep 1294°F72°F104°F 202664°F 201724%0%
Sep 1394°F72°F102°F 201166°F 201724%0%
Sep 1494°F72°F105°F 202367°F 201524%0%
Sep 1594°F71°F104°F 202366°F 200824%0%
Sep 1694°F71°F102°F 202662°F 200823%0%
Sep 1793°F71°F101°F 201658°F 200823%0%
Sep 1893°F71°F101°F 201664°F 200823%0%
Sep 1993°F70°F101°F 201664°F 200823%0%
Sep 2093°F70°F101°F 201764°F 200823%0%
Sep 2193°F70°F101°F 202361°F 201222%0%
Sep 2293°F70°F103°F 202363°F 201222%0%
Sep 2393°F69°F105°F 200560°F 202122%0%
Sep 2492°F69°F106°F 200558°F 202122%0%
Sep 2592°F69°F105°F 200563°F 202121%0%
Sep 2692°F69°F102°F 200560°F 200821%0%
Sep 2792°F68°F102°F 200561°F 200820%0%
Sep 2892°F68°F105°F 200556°F 201020%0%
Sep 2992°F68°F101°F 200556°F 202020%0%
Sep 3092°F68°F99°F 202353°F 202019%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Starr County, 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 7:15 AM, sunset 7:55 PM
September 30
sunrise 7:27 AM, sunset 7:22 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00417622 (Rio Grande City), public domain. Records: NOAA GHCN-Daily, station USW00012987, 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.