Climate and monthly weather forecastDehiwala, Sri Lanka

The climate of Dehiwala

The coastal town of Dehiwala, Sri Lanka, nests itself under the Köppen climate classification of Af, identifying itself prominently as a Tropical Rainforest Climate. Situated in the path of constant oceanic airflow, Dehiwala's relatively high altitude at sea level invites generous levels of humidity alongside substantial amounts of rainfall all year round.

Throughout the year, temperatures remain remarkably constant, spanning from 23.3°C (73.9°F) at their minimum to 31.4°C (88.5°F) at their maximum. This minimal fluctuation in temperatures establishes a balmy and warm climate all year round. It's interesting to note that the highest temperature peaks around April while the lowest recedes around December and January - a mild transition reflecting the local climatic patterns.

Relative humidity levels hover between 74% to 83% annually, leaning towards a rather moist climate due to its coastal vicinity. Rainfall patterns paint a dynamic picture, with the wettest months being May and June, averaging respective rainfall levels at around 312mm (12.28") and 315mm (12.4"). Precipitation generally intensifies beginning from March, with an emphasis during the mid-year months, then gradually subsides as the year ends.

The region also showcases a fairly moderate UV Index, indicating seven throughout most of the year, except in May and October where it slightly dips to six. Surprisingly, sunshine hours are fairly consistent throughout the year, varying mildly from six hours during November to nine hours during January to March.

The sea temperatures contribute to comfortable oceanic activities almost year-round, maintaining a range of 27.2°C (81°F) to 29.6°C (85.3°F). The perfect time to indulge in a swim would perhaps lie between March and May when sea temperatures reach their peak.

The best time to visit Dehiwala

Given the constant warmth and balmy temperatures, Dehiwala can indeed be considered an all-year-round location. However, if one has to identify a prime time to visit and experience the full breadth of its tropical beauty, it would be the early part of the year - specifically from February to April. During these months, the weather in Dehiwala is most conducive to outdoor activities, boasting optimum sea temperatures alongside the benefit of nine hours of sunshine each day.

The worst time to visit Dehiwala

Despite its consistent warmth, it is advisable to avoid Dehiwala during the mid-year months of May and June. These months see the highest intensity of rainfall at 312mm (12.28") to 315mm (12.4"), leading to potentially uncomfortable outdoor conditions and restricted activity options.

Spring weather in Dehiwala

Spring in Dehiwala, falling between March to May, provides a noticeably comfortable period. Despite temperatures peaking at 31.4°C (88.5°F), the presence of nine hours of sunshine and sea temperatures averaging 29.3°C (84.7°F) lends itself to an ideal spring. However, rainfall starts increasing significantly from March, potentially impacting outdoor activities.

Summer weather in Dehiwala

Despite heavy rainfall observed during June, the season of summer shows no drastic changes in temperature. The average highest dipping slightly to 29.1°C (84.4°F) and sea temperatures reducing to around 28.2°C (82.8°F), the weather in Dehiwala remains warm and conducive for beach activities.

Autumn weather in Dehiwala

Moving into Autumn, September to November sees Dehiwala weather stabilizing from the heavily rainy period, yet maintaining all its warmth with temperature highs persisting at around 29.7°C (85.5°F). A gradual dip in rainfall is also noted, making it a relatively dry and inviting season.

Winter weather in Dehiwala

Winter in Dehiwala, from December to February, is marked by a slight decrease in temperatures with the lowest reaching 24.1°C (75.4°F) in December. Despite the term 'winter,' weather conditions remain moderately warm while rainfall also lessens, making it a comparatively dry period to enjoy. The sea temperature starts picking up from its yearly lowest, making swimming a delightful activity even during this season.

Weather in January

The start of the year in Dehiwala, Sri Lanka, boasts mild climate with comfortable temperatures. January's weather indicates a favourable blend of moderate warmth and pleasing humidity, making it an enjoyable month for locals and visitors alike. Weather in January »

Weather in February

The mild aura of Dehiwala's weather continues in February as the climate remains fairly consistent with the previous month. The city's inhabitants observe an elevation in average temperature, a subtle yet noticeable difference from January. Weather in February »

Weather in March

The onset of March in Dehiwala brings a shift in the city's climate, with temperatures and humidity escalating. With the setting of February, March distinguishes itself as a warmer, more humid month, modulating the city's environment. Weather in March »

Weather in April

April here in Dehiwala, Sri Lanka, is marked by notably high levels of rainfall, as it is one of the peak months of the year for precipitation. Regardless of the season, the city manages to sustain its charm via its moderate to high temperatures and increased daylight hours. Weather in April »

Weather in May

The arrival of May in Dehiwala manifests intensified weather conditions featuring pouring rains and soaring humidity levels. The city undergoes minor variances in climate from April, albeit with an evident increase in precipitation. Weather in May »

Weather in June

June in Dehiwala denotes abundant rainfall and high humidity whilst maintaining moderately warm temperatures. As compared to May, June witnesses only slight variations in weather with a minor dip in rainfall. Having crossed the halfway mark of the year, June features the second highest rainfall measuring 315mm (12.4"). Weather in June »

Weather in July

July enters into Dehiwala, Sri Lanka, with an overarching reduction in daily rainfall. The city's summer climate characterizes this month with moderate warmth and high humidity. Transitioning from June, July experiences a decrease in maximum rainfall and temperature, thus indicating a shift in weather dynamics. Weather in July »

Weather in August

August in Dehiwala underlines a distinct precipitation pattern while retaining the city's moderately warm temperature. The differences between July and August aren't drastic in terms of temperature, though the city witnesses a distinct climb in rainfall levels. Weather in August »

Weather in September

As September arrives in Dehiwala, a distinct decrease in daily rainfall and cooler evenings commence. The weather pattern from August carries through with minor modulations, most notably in the declined precipitation. Setting a point of interest, September records 195mm (7.68") of rainfall, an appreciable decrease from the preceding month. Weather in September »

Weather in October

October in Dehiwala sees the continuation of the rainfall pattern from September, albeit with a slight increase in both day and night temperatures. The contrast in the city's climate between September and October is subtle yet discernible with slightly warmer days. Weather in October »

Weather in November

November in Dehiwala, Sri Lanka, brings about changes in the city's climatic conditions with a reduction in rainfall and moderate warmth. The transition from October to November brings about a considerable drop in precipitation yet maintains a consistently warm environment. Weather in November »

Weather in December

December marks the end of the year in Dehiwala with a continued decrease in rain accompanied by slightly cooler temperatures both during the day and night. The close comparison between November and December's weather places them on a similar spectrum despite slight changes in conditions. Weather in December »