May is the beginning of summer in the North of Vietnam, the hot and dry season in the Central Coast of Vietnam, the start of the rainy season in the Central Highlands and South of Vietnam.
May is a great time for family holidays and beach vacations on the Con Dao Islands and the Phu Quoc Island off the shore of southern Vietnam. During this time the sun shines everyday, the sea is calm and clear, it rains for only half an hour daily then stops, and the temperatures are pleasant (27-32oC).
The winds which affect Vietnam in May include:
- Northeasterly Wind in most of the North of Vietnam which is moist and which often causes short-lived rain making the temperatures pleasant;
- Westerly/Southwesterly Wind in the extreme Northwest of Vietnam, in much of the Central Coast of Vietnam and some parts of the Central Highlands of Vietnam which is also known as the foehn wind that causes heat strikes in these regions;
- Southwesterly Wind in the South of Vietnam which is moist and pleasant and which causes daily short-lived rain;
In May the Northeast of Vietnam has occasional rain, sunshine and often pleasant temperatures (22-30oC). The eastern side of the Northwest of Vietnam is similar to that in the Northeast except for that the temperatures are higher and there may be heat strikes. The extreme Northwest of Vietnam often has heat strikes and strong sun, less rain than the Northeast.
The Central Coast may have some rain, but mostly bright sunshine and high temperatures (23-37oC). The northern region (to the north of the Hai Van Pass) of the Central Coast from Thanh Hoa to Hue often has higher temperatures and heat strikes. The region to the south of the Central Coast from Da Nang to Phu Yen often has bright sunshine and nice temperatures (24-32oC).
The Central Highlands often have daily rain and warm or hot temperatures at mid day due to the foehn wind (35-38oC). But the temperatures are mostly nice thanks to high altitudes of the plateaus.
The South of Vietnam still has warm and hot days with temperatures from 26-36oC at the beginning of May but the temperatures turn to be more pleasant thanks to more daily rain.
Below is our review of the weather in Vietnam in May 2020.
1/ The mid of the first week formed a low pressure thermal air trough to the west of Vietnam which expanded and made the temperatures in most of the country hot (35-38oC). The heat was made worse due to the foehn effect in the extreme Northwest and North of the Central Coast of Vietnam.
2/ The thermal air trough to the west of Vietnam kept expanding and hot temperatures (above 36oC) were found across the country from the top North to the bottom South. It was mostly dry with daily bright sunshine.
At the beginning of the second week, t-storms with strong winds destroyed many houses in Lang Son, Thai Nguyen and Phu Tho.
From mid of the second week there was a weak spell of cool Northeasterly Monsoon in northern Vietnam which pushed the thermal air trough southward and which caused t-storms, heavy rains in most of northern Vietnam and the North of the Central Coast of Vietnam. The temperatures in the affected regions turned pleasant.
3/ In the third week of May 2020, there was a thermal air trough again to the west of Vietnam which made the temperatures high and humidity low in several places in the Northwest, in the Central Coast, in the Central Highlands and South of Vietnam. The high temperatures in these places are from above 35oC to 37oC.
From the middle of the third week, the rainy reason started in the Central Highlands and South of Vietnam with daily showers refreshing the air. The temperatures turned pleasant in the Central Highlands (23-33oC) while they remained high in most of the South of Vietnam (28-37oC).
The heat strike remained in most of Vietnam, except for the Central Highlands, throughout the third week with high temperatures at the end of the week in several places in the Central Coast above 40-42oC.
4/ The fourth week started with a high-pressure air mass which pushed the thermal air trough that had been causing the heat strike in most of Vietnam in the third week southward. T-storms with heavy rain were found in northern Vietnam and nicer temperatures returned in most of the North.
Coming toward the end of May 2020, the thermal air trough to the west of Vietnam kept expanding and high temperatures were found again in the North and the Central Coast of Vietnam.
The Central Highlands had mostly t-storms and pleasant temperatures. The South of Vietnam had t-storms with some heavy rain, hot temperatures at the beginning of the fought week and nice temperatures coming toward the end of the month.
