Saint John climate

Saint John Weather in September

NOAA 1991-2020 normals for St John, 0.5 km from Saint John

Average highs run from 79°F on September 1 to 68°F on September 30, and lows from 50°F to 43°F. Normal precipitation for the month is 0.56 in over about 4 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 Saint John, in °F, with the record for each date.20406080100151015202530
  • Normal low
  • Normal high
  • Record high
  • Record low

September at a glance

Average high
74°F
Average low
47°F
Precipitation
0.56 in
Record high
98°FSep 1, 2025
Record low
21°FSep 23, 2000
Chance of a freeze
32%
Days of 90°F or more
2.5
Daylight
13 h 20 min to 11 h 44 min
Cloud cover
48%
Humidity
52%
Dew point
41°F
Wind
7.6 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 179°F50°F98°F 202535°F 199912%0%
Sep 279°F50°F97°F 202530°F 199912%0%
Sep 379°F50°F96°F 199833°F 201112%0%
Sep 478°F49°F96°F 202035°F 201613%0%
Sep 578°F49°F92°F 199838°F 201213%0%
Sep 678°F49°F93°F 199836°F 200213%0%
Sep 777°F49°F95°F 202433°F 199913%0%
Sep 877°F49°F94°F 201134°F 200713%0%
Sep 977°F48°F91°F 201134°F 200714%0%
Sep 1076°F48°F93°F 201137°F 200514%0%
Sep 1176°F48°F95°F 201332°F 201214%0%
Sep 1276°F48°F92°F 201328°F 201214%0%
Sep 1375°F47°F90°F 201332°F 201615%0%
Sep 1475°F47°F93°F 200032°F 200615%0%
Sep 1574°F47°F93°F 199828°F 200615%0%
Sep 1674°F47°F91°F 200934°F 201716%0%
Sep 1774°F47°F92°F 200832°F 200616%0%
Sep 1873°F46°F86°F 200838°F 200216%0%
Sep 1973°F46°F92°F 200832°F 201816%0%
Sep 2072°F46°F86°F 201430°F 200717%0%
Sep 2172°F45°F88°F 201427°F 200217%0%
Sep 2272°F45°F85°F 199929°F 200017%0%
Sep 2371°F45°F93°F 200121°F 200017%0%
Sep 2471°F45°F95°F 201127°F 200518%0%
Sep 2570°F44°F87°F 202433°F 200218%0%
Sep 2670°F44°F86°F 201633°F 201518%0%
Sep 2769°F44°F89°F 202227°F 201519%0%
Sep 2869°F44°F86°F 202429°F 201519%0%
Sep 2968°F43°F83°F 202031°F 201920%0%
Sep 3068°F43°F85°F 200828°F 202420%0%

Chance of rain

The chance of at least 0.01 inch of precipitation on each date at Saint John, in percent, and of at least 0.1 inch of snowfall.051015201102030
  • Chance of a wet day
  • Chance of snowfall

Sunrise and sunset

Times for 2026, local time (PDT).

September 1
sunrise 6:10 AM, sunset 7:30 PM
September 30
sunrise 6:48 AM, sunset 6:32 PM

Every day of September: sun and moon

Other months

Sources

Normals: NOAA NCEI U.S. Climate Normals, 1991-2020, station USC00457267 (St John), public domain. Records: NOAA GHCN-Daily, station USW00094129, 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.