Mount Martha – current water temperature and swimming conditions

This page shows the current water temperature at Mount Martha in Victoria. You can view recent sea temperature trends on a 30-day chart, check typical monthly water temperature ranges, and compare today’s reading with historical averages for this date. The page also includes a 7-day water temperature forecast, nearby beaches with similar conditions, local weather information, and a summary of swimming conditions to help you assess how suitable the water is for swimming.

Current Sea Water Temperature

19.7°C

Today

19.7°C

Yesterday

20.2°C

A Week Ago

The average sea water temperature today in Mount Martha is about 20°C.

Water Temperature in Mount Martha: Daily Trends, Historical Records, and Forecast

⚠️ Water in this range feels cool but still manageable for many swimmers. Short to moderate swims are comfortable, especially in warm weather. Some people may prefer a wetsuit for longer stays, particularly when swimming actively or outside peak summer conditions.

It’s important to note that these swimming tips and recommendations apply only in settled weather. When air temperatures drop below 20°C — and sometimes even below 25°C — swimming can feel uncomfortable, even when water temperatures are relatively high.

Water Temperature Over the Last 30 Days

From February 18 to March 20

Over the past 30 days, water temperatures in Mount Martha have generally increased, although a slight cooling trend has set in over the last week.

According to our forecast, Sea water temperature in Mount Martha will be 18.9°C in the next 7 days. See the table below for daily data for the upcoming week.

Table of Daily Sea Temperature Data

Date	Current	Average	Forecast
Mar 12	19.2°C	19.8°C
Mar 13	19.5°C	19.3°C
Mar 14	20.2°C	19.3°C
Mar 15	19.9°C	19.5°C
Mar 16	19.7°C	19.5°C
Mar 17	19.6°C	19.5°C
Mar 18	19.6°C	19.3°C
Mar 19	19.7°C	19.0°C
Mar 20	19.7°C	19.0°C	19.7°C
Mar 21		19.3°C	19.6°C
Mar 22		19.3°C	19.5°C
Mar 23		19.3°C	19.3°C
Mar 24		18.8°C	19.2°C
Mar 25		18.3°C	19.1°C
Mar 26		18.5°C	19.0°C
Mar 27		18.8°C	18.9°C

* Current - Actual water temperature value

** Average - Average water temperature on this day in recent years

*** Forecast - Our water temperature forecast

Actual near-shore water temperatures in Mount Martha can vary by several degrees from the values shown, particularly after heavy rain, strong southerlies, or prolonged windy conditions. Certain wind patterns can trigger upwelling, where cooler, deeper water is pushed to the surface and replaces the warmer top layer, leading to noticeable short-term changes in water temperature.

Our water temperature forecast is produced using a proprietary mathematical model that combines real-time measurements with long-term historical patterns, local weather conditions, wind strength and direction, and air temperature specific to each coastal region. To improve accuracy, we cross-check data from nearby locations and use multiple sources, including offshore buoys, satellite-based sea surface maps, and observations provided by local authorities.

Annual Water Temperature Overview by Month

Monthly Water Temp Ranges

30°C

25°C

20°C

15°C

10°c

5°C

0°C

Annual Water Temperature Trend

Mount Martha sits along the eastern side of the Mornington Peninsula, facing the sheltered waters of Port Phillip Bay with the Bass Strait further south, and this setting keeps water temperatures relatively stable through the year. In summer, the bay usually warms to around 19–23 °C, which feels comfortable for swimming and spending long stretches in the water. Autumn often stays mild, with temperatures commonly between 17–21 °C, while spring is cooler at roughly 15–19 °C as the bay slowly warms after winter. During winter, water temperatures typically drop to about 13–15 °C, which feels cold but is still manageable for short swims on clear, calm days.

Monthly Water Temperature Range (Min, Max & Average)

Month	Min	Avg	Max
January	15°C	19°C	23°C
February	17°C	20°C	22°C
March	17°C	19°C	22°C
April	15°C	18°C	20°C
May	14°C	16°C	18°C
June	11°C	14°C	16°C
July	10°C	13°C	15°C
August	10°C	12°C	14°C
September	11°C	13°C	15°C
October	11°C	14°C	17°C
November	14°C	16°C	19°C
December	15°C	18°C	21°C

* Click on a month to view detailed water temperature data.

Mount Martha: Weather Forecast

March 21

15°C / 18°C

clear sky

humidity: 77% | wind: 14 kmh

March 22

17°C / 19°C

broken clouds: 51-84%

humidity: 71% | wind: 7 kmh

March 23

17°C / 19°C

clear sky

humidity: 69% | wind: 11 kmh

March 24

18°C / 19°C

broken clouds: 51-84%

humidity: 79% | wind: 7 kmh

Local Water Conditions and Nearby Spots

Nearby Beaches and Water Temperatures

Mount Martha South

⭐ 5.0/5

19.1°C

Mount Martha North

⭐ 5.0/5

19.8°C

Hawker

⭐ 3.3/5

19.9°C

Dava Beach

⭐ 2.5/5

20.4°C

Craigie

⭐ 3.3/5

20.3°C

Birdrock Beach

⭐ 2.9/5

20.8°C

Fossil Beach

⭐ 4.5/5

19.2°C

Mount Martha Point

⭐ 3.0/5

19.8°C

Fishermans Beach

⭐ 5.0/5

20.7°C

Swimming Conditions

Swimming in Mount Martha is allowed and is well suited to a wide range of swimmers. The beaches here are largely protected from strong Bass Strait swells, so waves are usually small and currents gentle, creating relaxed conditions that suit families and casual swimmers. Shallow water close to shore makes entry easy, especially in summer when the water is at its warmest. In cooler months, many locals continue to swim but keep sessions brief or use wetsuits for comfort. Overall, Mount Martha offers clean water, clear seasonal temperature changes, and reliable, low-stress swimming in a classic Mornington Peninsula bay setting.