Grantham — Current Water Temperature, Annual Trends and Forecast
This page provides information on the current water temperature in Grantham, trends, monthly ranges and the forecast for the coming days.
Current Water Temperature
Water Temperature in Grantham today is 19.5°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 |
|---|---|---|---|
| JUL 16 | 22.3°C | 18.0°C | |
| JUL 17 | 20.1°C | 18.0°C | |
| JUL 18 | 20.1°C | 18.0°C | |
| JUL 19 | 20.1°C | 18.0°C | |
| JUL 20 | 20.1°C | 18.0°C | |
| JUL 21 | 19.5°C | 18.0°C | |
| JUL 22 | 19.5°C | 18.0°C | |
| JUL 23 | 19.5°C | 18.0°C | |
| JUL 24 | 18.0°C | 19.4°C | |
| JUL 25 | 18.0°C | 19.4°C | |
| JUL 26 | 18.0°C | 19.3°C | |
| JUL 27 | 18.0°C | 19.2°C | |
| JUL 28 | 18.0°C | 19.1°C | |
| JUL 29 | 18.0°C | 19.1°C | |
| JUL 30 | 18.0°C | 19.0°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 | 0°C | 3°C | 6°C |
| February | 0°C | 4°C | 7°C |
| March | 2°C | 6°C | 9°C |
| April | 6°C | 9°C | 12°C |
| May | 9°C | 14°C | 19°C |
| June | 13°C | 18°C | 22°C |
| July | 14°C | 18°C | 23°C |
| August | 14°C | 18°C | 23°C |
| September | 10°C | 15°C | 19°C |
| October | 8°C | 11°C | 14°C |
| November | 3°C | 7°C | 11°C |
| December | 0°C | 4°C | 8°C |
Grantham: Weather Forecast
July 24
July 25
July 26
July 27
Location & Local Information
Grantham, a market town in Lincolnshire, lies near the upper reaches of the River Witham, where the river begins its slow journey toward Lincoln and the Fens. In this part of its course, the Witham is narrow and fresh, reflecting the mild but changeable climate of eastern England. During winter, the water temperature typically ranges between 3 and 5°C (37–41°F), remaining cold and brisk. By spring, it gradually warms to around 8–10°C (46–50°F). In midsummer, during July and August, the river can reach 17–19°C (63–66°F), particularly in shallow and sheltered areas. As autumn returns, it cools again to about 11–13°C (52–55°F), keeping a steady, refreshing flow through much of the year.
Swimming in the River Witham near Grantham is possible but not common, as the upper sections are shallow and often bordered by farmland. Those who do swim usually choose calm summer days and quiet stretches away from vegetation or livestock. The water is generally clean, though its flow can quicken after rainfall. Many people prefer to enjoy the river from the banks through walking, picnicking, or kayaking. The surrounding countryside, with its rolling fields and nearby Belton House estate, offers peaceful scenery that complements the gentle rhythm of the Witham Valley.