Climate averages 1991–2020
Acilia-Castel Fusano-Ostia Antica weather
in May.
A mild, moderately wet month: the 5th warmest and the 4th driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
May is a mild month in Acilia-Castel Fusano-Ostia Antica: daytime highs average 20.8°C and nights cool to about 14.5°C. By daytime temperature it is the 5th warmest of the 12 months.
Expect about 40 mm of rain on roughly 6 days, which makes May a moderately wet month (the 4th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 31 min on an average May day.
The nearest other city in this atlas is Fiumicino (8 km away). In May its highs average 20.6°C, about as warm as Acilia-Castel Fusano-Ostia Antica, with 40 mm of rain.
Among the 79 cities listed in Italy, Acilia-Castel Fusano-Ostia Antica ranks joint 63rd of 79 for the warmest May highs and joint 17th of 79 for the driest May (rainfall, lowest first). The mean May high of those 79 cities is 21.8°C; Acilia-Castel Fusano-Ostia Antica is 0.9°C cooler than that mean.
From May to June, average highs rise by 4.1°C to 24.9°C, and monthly rainfall falls from 40 mm to 22 mm.
The annual picture
May in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Acilia-Castel Fusano-Ostia Antica climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 12.0°C6.5°C | 6.5°C | 81 | 10.5 | 9.510 h |
| February | 12.3°C6.4°C | 6.4°C | 79 | 9.7 | 10.611 h |
| March | 14.4°C8.2°C | 8.2°C | 72 | 8.6 | 11.912 h |
| April | 16.9°C10.6°C | 10.6°C | 61 | 8.0 | 13.313 h |
| May, selected | 20.8°C14.5°C | 14.5°C | 40 | 6.0 | 14.515 h |
| June | 24.9°C18.4°C | 18.4°C | 22 | 3.3 | 15.215 h |
| July | 27.7°C21.2°C | 21.2°C | 15 | 1.8 | 14.915 h |
| August | 28.3°C21.8°C | 21.8°C | 21 | 2.6 | 13.914 h |
| September | 24.4°C18.6°C | 18.6°C | 86 | 7.8 | 12.513 h |
| October | 20.6°C15.3°C | 15.3°C | 131 | 10.4 | 11.111 h |
| November | 16.4°C11.5°C | 11.5°C | 161 | 13.3 | 9.910 h |
| December | 12.9°C7.9°C | 7.9°C | 115 | 11.7 | 9.29 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
May in nearby cities
- Fiumicino in MayItaly · 8 kmHigh 20.6°C · Low 14.7°C · 40 mm rain
- Rome in MayItaly · 21 kmHigh 22.3°C · Low 12.5°C · 58 mm rain
- Aprilia in MayItaly · 33 kmHigh 21.1°C · Low 13.5°C · 53 mm rain
- Guidonia Montecelio in MayItaly · 41 kmHigh 22.9°C · Low 11.5°C · 77 mm rain
- Latina in MayItaly · 58 kmHigh 21.8°C · Low 13.4°C · 65 mm rain
- Terni in MayItaly · 93 kmHigh 22.9°C · Low 11.4°C · 83 mm rain
- Perugia in MayItaly · 150 kmHigh 20.1°C · Low 9.3°C · 69 mm rain
- Pescara in MayItaly · 173 kmHigh 21.4°C · Low 13.4°C · 54 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Acilia-Castel Fusano-Ostia Antica) is explained once on the Acilia-Castel Fusano-Ostia Antica year overview and on the Sources, method and limits page.
Fiumicino lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.