Weather in Jaffna in May

A good month. May is a solid month to be in Jaffna. Highs average 30.9 °C, lows 28.5 °C, and rain falls on 10 days — nothing in the month is working against you.

May ranks 8 of 12 in Jaffna: past the worst of the year but short of January, which is the month to book if the dates are open.

Rain on 10 days, 2 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for 30.9 °C days and 28.5 °C nights; the spread matters more here than any single number.

What the averages hide

Averages flatten a month, and this one hides a few things: 27 days top 30 °C, making the heat continuous rather than occasional; the day barely swings — 2.4 °C between the overnight low and the afternoon high. Across the twenty years measured, the hottest May day reached 33.4 °C and the coldest night fell to 26.9 °C, and the wettest single day dropped 141 mm — roughly 181% of the month's rain in one day.

This is the volatile part. May rainfall has ranged from 6 mm to 279 mm across the twenty years measured — a 273 mm spread around an average of 78 mm. The average is real but almost no individual May looks like it, so treat the figure as the middle of a wide range rather than a forecast.

Wind sits around 21.4 km/h — a steady breeze rather than a nuisance, and welcome on the warmer days, and humidity runs at 79%, high enough to notice on the warm days without dominating them.

How May sits in the year

Temperatures hold steady either side: 31.5 °C in April, 30.9 here, 30.5 in June. Nothing about the timing within the month matters much. Rain is the thing that moves: June brings 6 days less of it, so pushing the dates later buys drier weather.

Daylight in May

Jaffna sits close enough to the equator that daylight barely moves all year — 12.6 hours in May, against a range of just 1.1 hours across the whole calendar. Sunrise and sunset land at roughly the same time whenever you come.

Sea temperature

The sea sits at about 30 °C in May — warm enough that the water offers no relief from the heat. This is the warmest the water gets all year.

How busy it gets

Quiet. Few other visitors, cheaper rooms, and a real chance some seasonal operators are shut.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

May in Jaffna versus nearby

If Jaffna is one option among several, the nearby comparison is worth making. Trincomalee is the weaker option in May — within a degree on temperature, 1 day more rain. Madurai is the weaker option in May — 5.5 °C warmer, 3 days more rain.

So: May is a compromise. January is 24 points better and is what Jaffna is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.

Every month in Jaffna

See all twelve months in Jaffna, or where else to go in May.