WeatherJourney.com

Port Blair weather by month: averages, rainfall & climate trends

Port Blair is warm in every month of the year; the seasonal dip amounts to just 1.9°C. Rainfall leans toward the stretch from May to November. Port Blair weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+1.6°Chigh above average

29° / 27°Today
27° / 26°Average
see today in detail →

How it's changed

+0.9°Caverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–496days above 30°C a year now (2016–2025) · 0 in the 1940sdays above 30°C · 0 in the 1940s+0.9°C vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 54 mmhigh 27°low 25°February, rain 25 mmhigh 27°low 25°March, rain 30 mmhigh 28°low 26°April, rain 83 mmhigh 29°low 27°May, rain 299 mmhigh 29°low 27°June, rain 353 mmhigh 28°low 26°July, rain 304 mmhigh 28°low 26°August, rain 315 mmhigh 28°low 26°September, rain 332 mmhigh 27°low 26°October, rain 287 mmhigh 27°low 26°November, rain 228 mmhigh 27°low 26°December, rain 138 mmhigh 27°low 26°wettest month June, 353 mm · 2,449 mm a yearsee month by month →

Right now

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

Right now

26.8°

33°feels like
89%humidity
25°dew point
4 km/hfrom S
UV index0.0
sunrise05:09sunset16:56day length11h 46m
TodayShowers29°27°
TueOvercast29°26°
WedLight rain27°26°
ThuOvercast29°25°
FriOvercast29°26°
SatPartly cloudy30°27°
SunOvercast31°27°

On this date: October 26

Today (forecast)
29° / 27°
Average for October 26
27° / 26°

High above average · +1.6°C

  • Highest since 1940: 28.8° · 2019
  • Lowest since 1940: 23.9° · 1942
  • One year ago: 27° / 26°

Every October 26 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 26 on record (n = 87). 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 Port Blair is sampled from the ECMWF ERA5 reanalysis at 11.67°N, 92.75°E, with daily records since 1940.

Coordinates
11.67°N, 92.75°E
Time zone
Asia/Kolkata
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

31 of the last 31 days were warmer than the historical average for that date. Average difference: +1.3°C.

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

The year peaks in April, at around 28.6°C by mid-afternoon, with nights around 27.0°C. In January, the coolest month, afternoons reach about 26.6°C and nights dip to 25.2°C.

In total, Port Blair averages about 2,449 mm of precipitation a year; June is usually the wettest month (353 mm) and February the driest (25 mm).

Over the full record (since 1940), the annual mean temperature in Port Blair has risen by 0.9°C between its first decade and its last. That last decade has also been the warmest in the record.

Climate graph (climograph)

April is the warmest month, January the coolest: a yearly swing of 2°C. Wettest month: June (~353 mm). Whole year averages ~2,449 mm 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).

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.

Port Blair 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 lowRainDaylightHighestLowest
January26.6°25.2°54 mm11.4 h28.5° (1998)22.4° (1953)
February27.0°25.4°25 mm11.6 h29.1° (2005)22.9° (1997)
March27.7°26.2°30 mm11.9 h29.6° (1998)23.6° (1953)
April28.6°27.0°83 mm12.3 h30.8° (2016)23.3° (1953)
May28.5°26.7°299 mm12.5 h31.0° (1998)24.6° (1943)
June28.1°26.4°353 mm12.7 h29.5° (2023)24.9° (1956)
July27.7°26.1°304 mm12.6 h29.0° (2002)24.6° (1956)
August27.6°26.0°315 mm12.4 h28.9° (2024)24.5° (1943)
September27.3°25.8°332 mm12.1 h28.8° (2010)24.4° (1956)
October27.2°25.7°287 mm11.7 h29.1° (2018)23.8° (1942)
November27.3°25.8°228 mm11.5 h29.4° (1997)23.2° (1953)
December27.0°25.7°138 mm11.3 h28.9° (1997)22.3° (1952)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +0.9°C.

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: +0.11°C 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

Sep–Nov is warming fastest: +0.12°C 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 ≥ 30°C per year: 0.0 early in the record → 5.5 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 1998, coldest in 1952: 31.0°C / 22.3°C.

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

Annual rainfall

~2,449 mm/year on average. Last decade: −1% vs that average. Long-term trend: −74 mm 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 Port Blair

Which is the warmest month in Port Blair?
On long-term average, the warmest month in Port Blair is April (mean daily temperature of about 27.9°C) and the coolest is January (about 26.0°C).
How does today's temperature in Port Blair compare to the historical average?
On October 26, 2026, Port Blair is forecast to reach a high of 28.9°C and a low of 26.6°C. The long-term average for this date (the full record since 1940) is a high of 27.3°C and a low of 25.6°C, so today's high is 1.6°C warmer than that average.
How much has Port Blair warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Port Blair is about 0.9°C warmer.
How much does it rain in Port Blair?
Port Blair receives about 2,449 mm of precipitation per year on long-term average, with June typically the wettest month.
What is the average temperature in Port Blair?
Over the full record (since 1940), the annual mean temperature in Port Blair is about 26.9°C. The warmest month is April and the coolest is January.
What are the average temperatures in Port Blair by month?
Average daily highs and lows for each month in Port Blair (°C, full record since 1940): January 27°/25°, February 27°/25°, March 28°/26°, April 29°/27°, May 29°/27°, June 28°/26°, July 28°/26°, August 28°/26°, September 27°/26°, October 27°/26°, November 27°/26°, December 27°/26°.

Weather in nearby cities