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St. Petersburg weather by month: averages, rainfall & climate trends

Average temperatures in St. Petersburg follow a clear seasonal rhythm, rising and falling by 20.3°F over the course of the year. The heavier rain months run from June to September. St. Petersburg weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+1.6°Fhigh near average

80° / 60°Today
78° / 71°Average
see today in detail →

How it's changed

+0.8°Faverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4927days above 86°F a year now (2016–2025) · 6 in the 1940sdays above 86°F · 6 in the 1940s+0.8°F vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 2.3 incheshigh 65°low 58°February, rain 2.2 incheshigh 66°low 59°March, rain 2.7 incheshigh 69°low 63°April, rain 1.8 incheshigh 74°low 68°May, rain 2.0 incheshigh 79°low 73°June, rain 4.8 incheshigh 83°low 78°July, rain 5.5 incheshigh 84°low 79°August, rain 6.0 incheshigh 84°low 79°September, rain 5.5 incheshigh 83°low 77°October, rain 2.4 incheshigh 79°low 72°November, rain 1.6 incheshigh 73°low 65°December, rain 2.0 incheshigh 68°low 61°wettest month August, 6.0 inches · 38.9 inches a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Clear

Right now

60.1°

59°feels like
83%humidity
55°dew point
6 mphfrom N
UV index0.0
sunrise07:34sunset18:55day length11h 21m
TodayClear80°60°
ThuClear78°60°
FriClear82°65°
SatClear84°67°
SunClear83°72°
MonClear85°69°
TueClear85°69°

On this date: October 21

Today (forecast)
80° / 60°
Average for October 21
78° / 71°

High near average · +1.6°F

  • Highest since 1940: 83.0° · 1985
  • Lowest since 1940: 54.6° · 1989
  • One year ago: 79° / 73°

Every October 21 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 21 on record (n = 86). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for St. Petersburg is sampled from the ECMWF ERA5 reanalysis at 27.77°N, 82.68°W, with daily records since 1940.

Coordinates
27.77°N, 82.68°W
Time zone
America/New York
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

23 of the last 30 days were warmer than the historical average for that date. Average difference: +0.4°F.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

August brings the year's peak warmth, with afternoons typically reaching 84.4°F and nights around 79.1°F. In a typical recent year, around 25 days reach 86°F or more. The coolest month is January, when afternoons reach about 65.5°F and overnight lows sit around 57.7°F. Freezing temperatures almost never occur.

In total, St. Petersburg averages about 38.9 inches of precipitation a year; August is usually the wettest month (6.0 inches) and November the driest (1.6 inches).

Comparing the record's first decade with its most recent one, St. Petersburg now averages 0.8°F warmer than it did in the 1940s. Recent years have brought more rain as well. The last decade sits roughly 18% over the long-term average.

Climate graph (climograph)

August is the warmest month, January the coolest: a yearly swing of 20°F. Wettest month: August (~6.0 in). Whole year averages ~38.9 inches of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Rainy days by month

About 98 rainy days a year: most in August (~17), fewest in November (~4).

Bars = average number of days with ≥ 0.08 in per month. Hover for the monthly rainfall total.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

St. Petersburg month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainRainy daysDaylightHighestLowest
January65.5°57.7°2.3 in510.4 h75.4° (2013)33.6° (2003)
February66.0°58.8°2.2 in511.0 h77.4° (2018)34.6° (1996)
March69.5°62.6°2.7 in511.8 h79.2° (2020)40.5° (1996)
April74.2°67.7°1.8 in412.7 h83.7° (2002)51.7° (1987)
May79.2°73.3°2.0 in513.4 h88.1° (1953)59.9° (1999)
June82.7°77.6°4.8 in1213.7 h89.4° (2010)66.1° (1984)
July84.0°79.1°5.5 in1713.6 h90.0° (1964)74.1° (1974)
August84.4°79.1°6.0 in1713.0 h90.8° (2023)71.6° (1957)
September83.5°77.5°5.5 in1312.2 h90.5° (1963)65.4° (1962)
October79.3°72.3°2.4 in611.3 h87.4° (2005)52.1° (2008)
November73.0°65.5°1.6 in410.6 h83.2° (2015)40.1° (1970)
December68.4°60.6°2.0 in510.3 h78.8° (1972)31.2° (1962)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +0.8°F.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.12°F per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Mar–May is warming fastest: +0.18°F per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 86°F per year: 6.4 early in the record → 26.7 recently. Frost days: 0 → 0.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 2023, coldest in 1962: 90.8°F / 31.2°F.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~38.9 in/year on average. Last decade: +18% vs that average. Long-term trend: +0.91 in per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about St. Petersburg

Which is the warmest month in St. Petersburg?
On long-term average, the warmest month in St. Petersburg is August (mean daily temperature of about 81.6°F) and the coolest is January (about 61.2°F).
How does today's temperature in St. Petersburg compare to the historical average?
On October 21, 2026, St. Petersburg is forecast to reach a high of 79.5°F and a low of 59.7°F. The long-term average for this date (the full record since 1940) is a high of 77.9°F and a low of 71.0°F, so today's high is 1.6°F warmer than that average.
How much has St. Petersburg warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in St. Petersburg is about 0.8°F warmer.
How much does it rain in St. Petersburg?
St. Petersburg receives about 38.9 inches of precipitation per year on long-term average, with August typically the wettest month.
What is the average temperature in St. Petersburg?
Over the full record (since 1940), the annual mean temperature in St. Petersburg is about 72.4°F. The warmest month is August and the coolest is January.
What are the average temperatures in St. Petersburg by month?
Average daily highs and lows for each month in St. Petersburg (°F, full record since 1940): January 65°/58°, February 66°/59°, March 69°/63°, April 74°/68°, May 79°/73°, June 83°/78°, July 84°/79°, August 84°/79°, September 83°/77°, October 79°/72°, November 73°/65°, December 68°/61°.
What is the weather like in St. Petersburg in summer?
In summer, June through August, St. Petersburg is wet and warm. Expect 83–84°F by day and 78–79°F at night, with August the warmest month. Rain is steady at around 5.4 inches a month, spread over roughly 15 days. No season is wetter.
What is the weather like in St. Petersburg in winter?
In winter, December through February, St. Petersburg is mild. Daytime highs sit at 65–68°F and nights at 58–61°F; January is the coldest month. Rain falls on about 5 days a month, adding up to around 2.2 inches.
What is the weather like in St. Petersburg in spring?
March to May is spring in St. Petersburg, and it is pleasantly warm. It warms from 69°F by day and 63°F at night in March to 79°F and 73°F in May. Rain is steady at around 2.2 inches a month, spread over roughly 5 days.
What is the weather like in St. Petersburg in autumn?
Autumn in St. Petersburg (September to November) is pleasantly warm. September is still 83°F by day and 77°F at night; by November it is down to 73°F and 65°F. Rain eases through the season: 13 rainy days and 5.5 inches in September, 4 days and 1.6 inches in November.
How many days a year does it rain in St. Petersburg?
On long-term average, St. Petersburg has about 98 days a year with at least 0.08 inches of rain or snow. The annual total is roughly 38.9 inches.

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