Italy
Best Time to Dive in Sicily / Ustica
38.69°N 13.18°E
The best conditions run May to September once the water has warmed to 25 °C from 17. Too few records to show a wildlife season, so the weather picks the month.
- Best time
- May–Sep
- Water
- 15–28 °C
- Visibility
- 20–35 m
- Dived from
- day boat
- Tidal range
- 0.2–0.3 m
- Species logged
- 1
Worth knowing: 36% of days see seas over 1.5 m.
Where it is
111 km across · coastline from Natural Earth 10m
Diving in Sicily / Ustica — monthly breakdown
A year of scuba diving conditions at a glance. Hover a month to isolate it.
| January | February | March | April | May | June | July | August | September | October | November | December | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Conditions | Poor | Poor | Poor | Moderate | Good | Excellent | Excellent | Excellent | Good | Moderate | Poor | Poor |
| Water temp (°C) | 16 | 15 | 15 | 16 | 19 | 23 | 27 | 28 | 26 | 23 | 20 | 17 |
| Visibility (m) | 20–30 | 20–30 | 20–30 | 20–30 | 25–35 | 25–35 | 25–35 | 25–35 | 25–35 | 25–35 | 20–30 | 20–30 |
| Marine life | Quiet | Quiet | Quiet | Steady | Steady | Steady | Steady | Quiet | Quiet | Quiet | Quiet | Steady |
| Best time | Peak | Peak | Peak | Peak | Peak |
Excellent Good Moderate PoorPeak season May–Sep
Long-term averages, 2016–2025. Visibility is estimated from satellite chlorophyll-a. Water temperature is the surface mean; it is cooler at depth.
The Sicily / Ustica diving season
April · Shoulder season
1 monthJFMAMJJASOND
- Water temperature
- 16–16 °C
- Visibility
- 20–30 m
- Rain
- 5 days a month
Diving conditionsThe sea is rougher. It rains less.
May to September · Peak season
5 monthsJFMAMJJASOND
- Water temperature
- 19–28 °C
- Visibility
- 25–35 m
- Rain
- 4 days a month
Diving conditionsSeas stay mostly calm. The wind eases. It rains less.
October · Shoulder season
1 monthJFMAMJJASOND
- Water temperature
- 23–23 °C
- Visibility
- 25–35 m
- Rain
- 9 days a month
Diving conditionsSeas stay mostly calm. It rains more.
November to March · Off season
5 monthsJFMAMJJASOND
- Water temperature
- 15–20 °C
- Visibility
- 20–30 m
- Rain
- 10 days a month
Diving conditionsExpect some swell. The wind is up. It rains more.
- Water temperature is satellite sea-surface temperature, so expect it cooler below the thermocline.
- Visibility is estimated from satellite chlorophyll-a.
Sicily / Ustica water temperature and weather
121 underwater observation records · 9 surveyed years of ocean data · 10 years of sea temperature
Water & weather
Sicily / Ustica water temperature by month
The dashed line is the monthly average. Eight days in ten fall inside the band.
10th to 90th percentile rangemonthly mean
8
rough days a month
Seas top 1.5 m on 26% of days. Enough to cancel a day boat
5
blowy days a month
Gusts over 40 km/h, about where a day boat stays in port
7
wet days a month
1 of them bring heavy rain
| Month | Swell | Gusts over 40 km/h | Wet days | Heavy rain | Air | Daylight |
|---|---|---|---|---|---|---|
| January | 3.3 m | 34% | 11 | 1 | 15 °C | 9.6 h |
| February | 2.8 m | 27% | 7 | 1 | 14 °C | 10.5 h |
| March | 2.7 m | 24% | 10 | 2 | 15 °C | 11.7 h |
| April | 2.3 m | 12% | 5 | 1 | 16 °C | 13.0 h |
| May | 1.5 m | 7% | 6 | 1 | 19 °C | 14.1 h |
| June | 1.0 m | 2% | 2 | 0 | 24 °C | 14.7 h |
| July | 1.6 m | 3% | 1 | 0 | 27 °C | 14.5 h |
| August | 1.5 m | 2% | 3 | 1 | 28 °C | 13.5 h |
| September | 1.9 m | 9% | 7 | 2 | 26 °C | 12.2 h |
| October | 2.2 m | 15% | 9 | 2 | 23 °C | 11.0 h |
| November | 3.2 m | 29% | 14 | 4 | 19 °C | 9.8 h |
| December | 2.7 m | 35% | 10 | 2 | 16 °C | 9.3 h |
Swell is the rough end of the month: nine days in ten come in under it. Sea temperature covers 10 years, waves 4.
Pick your week
48 weeks from the daily record. Darker is better, against this site's own year. Pick a month for the detail.
| Week 1 | January week 1: Poor | February week 1: Poor | March week 1: Poor | April week 1: Poor | May week 1: Moderate | June week 1: Excellent | July week 1: Excellent | August week 1: Excellent | September week 1: Excellent | October week 1: Good | November week 1: Moderate | December week 1: Poor |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Week 2 | January week 2: Poor | February week 2: Poor | March week 2: Poor | April week 2: Moderate | May week 2: Moderate | June week 2: Excellent | July week 2: Excellent | August week 2: Excellent | September week 2: Good | October week 2: Good | November week 2: Poor | December week 2: Poor |
| Week 3 | January week 3: Poor | February week 3: Moderate | March week 3: Moderate | April week 3: Moderate | May week 3: Moderate | June week 3: Excellent | July week 3: Excellent | August week 3: Excellent | September week 3: Good | October week 3: Moderate | November week 3: Poor | December week 3: Poor |
| Week 4 | January week 4: Moderate | February week 4: Poor | March week 4: Moderate | April week 4: Good | May week 4: Excellent | June week 4: Excellent | July week 4: Excellent | August week 4: Good | September week 4: Moderate | October week 4: Poor | November week 4: Poor | December week 4: Moderate |
Excellent Good Moderate PoorBest week to go: fourth of June
January, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 16 °C | 3.2 m | 36 km/h | 38% |
| Week 2 | Poor | 16 °C | 4.1 m | 37 km/h | 44% |
| Week 3 | Poor | 15 °C | 3.4 m | 34 km/h | 38% |
| Week 4 | Moderate | 15 °C | 2.4 m | 31 km/h | 27% |
February, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 15 °C | 2.8 m | 33 km/h | 26% |
| Week 2 | Poor | 15 °C | 2.9 m | 31 km/h | 26% |
| Week 3 | Moderate | 15 °C | 2.6 m | 25 km/h | 20% |
| Week 4 | Poor | 15 °C | 2.6 m | 29 km/h | 24% |
March, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 15 °C | 2.6 m | 34 km/h | 37% |
| Week 2 | Poor | 15 °C | 2.6 m | 32 km/h | 35% |
| Week 3 | Moderate | 15 °C | 2.3 m | 27 km/h | 29% |
| Week 4 | Moderate | 15 °C | 2.6 m | 26 km/h | 26% |
April, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 15 °C | 2.6 m | 26 km/h | 21% |
| Week 2 | Moderate | 16 °C | 2.4 m | 26 km/h | 19% |
| Week 3 | Moderate | 16 °C | 2.4 m | 26 km/h | 16% |
| Week 4 | Good | 17 °C | 2.0 m | 24 km/h | 16% |
May, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 17 °C | 1.5 m | 23 km/h | 20% |
| Week 2 | Moderate | 18 °C | 1.5 m | 23 km/h | 23% |
| Week 3 | Moderate | 19 °C | 1.5 m | 24 km/h | 19% |
| Week 4 | Excellent | 20 °C | 1.2 m | 20 km/h | 10% |
June, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 21 °C | 1.0 m | 19 km/h | 8% |
| Week 2 | Excellent | 23 °C | 1.1 m | 20 km/h | 9% |
| Week 3 | Excellent | 24 °C | 1.1 m | 19 km/h | 7% |
| Week 4 | Excellent | 25 °C | 1.0 m | 19 km/h | 3% |
July, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 26 °C | 1.3 m | 19 km/h | 1% |
| Week 2 | Excellent | 27 °C | 1.3 m | 18 km/h | 4% |
| Week 3 | Excellent | 27 °C | 1.3 m | 18 km/h | 5% |
| Week 4 | Excellent | 27 °C | 1.7 m | 17 km/h | 2% |
August, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 28 °C | 1.6 m | 17 km/h | 4% |
| Week 2 | Excellent | 28 °C | 1.2 m | 17 km/h | 8% |
| Week 3 | Excellent | 28 °C | 1.3 m | 17 km/h | 11% |
| Week 4 | Good | 28 °C | 1.6 m | 18 km/h | 12% |
September, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Excellent | 27 °C | 1.7 m | 20 km/h | 15% |
| Week 2 | Good | 27 °C | 2.0 m | 21 km/h | 20% |
| Week 3 | Good | 26 °C | 2.0 m | 23 km/h | 21% |
| Week 4 | Moderate | 25 °C | 1.9 m | 25 km/h | 25% |
October, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Good | 25 °C | 2.0 m | 26 km/h | 28% |
| Week 2 | Good | 24 °C | 1.7 m | 25 km/h | 29% |
| Week 3 | Moderate | 23 °C | 1.9 m | 24 km/h | 28% |
| Week 4 | Poor | 22 °C | 2.5 m | 26 km/h | 29% |
November, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Moderate | 22 °C | 2.6 m | 27 km/h | 38% |
| Week 2 | Poor | 21 °C | 2.6 m | 30 km/h | 44% |
| Week 3 | Poor | 20 °C | 3.4 m | 31 km/h | 48% |
| Week 4 | Poor | 19 °C | 3.6 m | 34 km/h | 49% |
December, week by week
| Week | Conditions | Water | Swell | Wind | Rain chance |
|---|---|---|---|---|---|
| Week 1 | Poor | 18 °C | 2.8 m | 35 km/h | 44% |
| Week 2 | Poor | 18 °C | 2.7 m | 35 km/h | 39% |
| Week 3 | Poor | 17 °C | 3.1 m | 32 km/h | 29% |
| Week 4 | Moderate | 16 °C | 2.8 m | 31 km/h | 26% |
10 years of daily records, averaged into weeks.
Gear & storms
What to wear
Off the coldest water of each month, not the average — that is what the suit has to cope with.
| January | February | March | April | May | June | July | August | September | October | November | December | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Suit | January: 7 mm | February: 7 mm | March: 7 mm | April: 7 mm | May: 7 mm | June: 5 mm | July: 3 mm | August: 3 mm | September: 3 mm | October: 5 mm | November: 5 mm + | December: 7 mm |
- Dec–May7 mm semi-dry
- Jun5 mm full suit
- Jul–Sep3 mm full suit
- Oct5 mm full suit
- Nov5 mm with hood and gloves
Swell through the year
The rough end of each month — nine days in ten come in under it.
Amber is over 1.5 m.
Tides
Tropical storms
No tropical storm has come within 250 km in 30 years of records. Swell and wind set the season, not cyclones.
- NOAASea surface temperature, from OISST and MUR
- ERA5Wind, waves, rain and air temperature, via Open-Meteo
- OBISMarine species records within 60 km
- IBTrACSTropical cyclone tracks, 1996 to 2025
Sicily / Ustica marine life — what you'll see diving
Only 121 records have been logged within 60 km. A thin record is not an empty reef.
| Species | When | Observed window | Reliability | Evidence | Records |
|---|---|---|---|---|---|
| Loggerhead turtle | Apr, Jul | Likely | 111 |
Peak Present
- Observed window
- Months with records. Peak is where most of them fall.
- Reliability
- Near-guaranteed in 60% of surveyed years or more
- Likely 30% to 60%
- Hit-or-miss under 30%
- Evidence
- Years it was seen, out of the years anyone surveyed.
- Records
- OBIS sightings within 60 km.
These are sightings people logged, not a full survey of the reef. A species missing from a month may just mean nobody recorded one.
Diving Sicily / Ustica — common questions
- When is the best time to dive Sicily / Ustica?
- The best conditions run May to September once the water has warmed to 25 °C from 17. Too few records to show a wildlife season, so the weather picks the month.
- When is the diving season in Sicily / Ustica?
- The diving season in Sicily / Ustica runs May to September.
- Is the diving in Sicily / Ustica good for beginners?
- Yes. It suits Open Water divers, so it works for a first trip after certification.
- How warm is the water in Sicily / Ustica?
- Between 15 and 28 °C at the surface across the year, coldest in February and warmest in August. It runs cooler below the thermocline.
- What wetsuit do I need in Sicily / Ustica?
- A 7 mm semi-dry covers the coldest water of the year. In the warmest months a 3 mm full suit is enough.
- What is the visibility like in Sicily / Ustica?
- Roughly 20 to 35 m depending on the month. That is estimated from satellite chlorophyll-a rather than measured in the water.
- What will I see diving Sicily / Ustica?
- The most consistently recorded species are Loggerhead turtle (likely), from 121 records within 60 km.
- Does Sicily / Ustica get tropical storms?
- No. None has passed within 250 km in 30 years of records.
- Is there current in Sicily / Ustica?
- The tide rises and falls 0.3 m around the full and new moon, against 0.2 m in between. How much of that becomes current depends on the shape of the channel.
- When should I avoid Sicily / Ustica?
- January–February, November are the weakest months for conditions.
- How do you dive Sicily / Ustica?
- Mostly from day boats. Trips run through the season, May–Sep.