Lis River — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in the Lis River, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in the Lis River today is 19.6°C.
Water Temperature: Daily Trends, Historical Records, and Forecast
⚠️ As of today, the minimum water temperature ranges from 65°F (18°C) to 68°F (20°C). This is already quite warm water, which is ideal for most people. Swimming becomes comfortable, and prolonged stays in the water do not cause discomfort. This temperature is perfect for family trips and for those who prefer warmer water. It is also comfortable for water sports such as surfing or swimming. It is important to note that these swimming tips and recommendations apply only in good weather. When the air temperature is below 68°F (20°C), and sometimes even below 77°F (25°C), swimming can be unpleasant even with relatively high water temperatures.
Water Temperature Chart Over the Last 30 Days
Table of Daily Sea Temperature Data
| Date | Current | Average | Forecast |
|---|---|---|---|
| AUG 26 | 22.6°C | 23.0°C | |
| AUG 27 | 20.8°C | 23.0°C | |
| AUG 28 | 20.7°C | 23.0°C | |
| AUG 29 | 20.7°C | 23.0°C | |
| AUG 30 | 20.7°C | 23.0°C | |
| AUG 31 | 20.8°C | 23.0°C | |
| SEP 1 | 20.8°C | 22.0°C | |
| SEP 2 | 20.3°C | 22.0°C | |
| SEP 3 | 22.0°C | 19.7°C | |
| SEP 4 | 22.0°C | 19.8°C | |
| SEP 5 | 22.0°C | 20.0°C | |
| SEP 6 | 22.0°C | 20.1°C | |
| SEP 7 | 22.0°C | 20.2°C | |
| SEP 8 | 22.0°C | 20.3°C | |
| SEP 9 | 22.0°C | 20.4°C |
* Current - Actual water temperature value
** Average - Average water temperature on this day in recent years
*** Forecast - Our water temperature forecast
Actual nearshore water temperatures may fluctuate by several degrees from the reported values, especially following heavy rainfall or extended periods of strong winds. Certain wind patterns can cause colder, deeper waters to rise and replace the sun-warmed surface water, leading to noticeable variations.
Our forecast is based on a proprietary mathematical model that considers real-time water temperature changes, historical trends, key weather patterns, wind strength and direction, and air temperature specific to each region. Additionally, we incorporate data from other resorts to enhance accuracy.
Monthly Water Temperature Range (Min, Max & Average)
| Month | Min | Avg | Max |
|---|---|---|---|
| January | 6°C | 9°C | 12°C |
| February | 6°C | 9°C | 13°C |
| March | 9°C | 12°C | 15°C |
| April | 9°C | 13°C | 17°C |
| May | 10°C | 15°C | 21°C |
| June | 16°C | 20°C | 25°C |
| July | 18°C | 23°C | 27°C |
| August | 18°C | 23°C | 27°C |
| September | 18°C | 22°C | 27°C |
| October | 14°C | 18°C | 20°C |
| November | 11°C | 15°C | 18°C |
| December | 8°C | 11°C | 14°C |
Lis River: Water Temperature by Location
Lis River: Weather Forecast
September 3
September 4
September 5
September 6
September 7
September 8
Location & Local Information
Source:
• location Fontes, Cortes (Leiria)
Mouth Praia da Vieira
Length 39.5 km (24.5 mi)
The Rio Lis, in Leiria District, typically shows seasonal water temperatures that reflect the temperate coastal climate of central Portugal. In winter the river is cooler, often ranging from about 8–12 °C (46–54 °F). Spring brings a gradual warming to roughly 12–18 °C (54–64 °F) as air temperatures rise and flows moderate. In summer shallow stretches and slower reaches commonly warm to approximately 18–24 °C (64–75 °F), with the warmest spots on sunny days reaching the upper part of that range. Autumn temperatures usually fall back to around 12–18 °C (54–64 °F) as rains increase and solar heating diminishes.
Swimming in the Rio Lis is possible in many accessible sections, and local populations often use quieter pools and designated river beaches in warmer months. Whether swimming is allowed or advisable depends on location-specific factors: municipal management, water quality monitoring, river flow and currents, and the presence of safe access points. Some stretches are maintained for bathing and show acceptable quality during summer, while others are unsuitable due to stronger currents, infrastructure, or occasional contamination after heavy rain. Observing local signage and municipal advisories is therefore important before entering the water.