Do you need to know, when is the best time to go to Yemen? Then you should take a look here, what weather you can expect there during the year.
The climate of Yemen is mostly desert. You can expect hot and humid weather along west coast, but climate is temperate in western mountains and it is affected by seasonal monsoon. You can also expect very hot, dry and harsh climate in the east.
When speaking about the usual weather in this state, the information is relevant for example for these popular places: Aden, Al Hudayda, Al Mukalla, Haraz Mountains, Kawkaban, Red Sea Islands, Sana'a, Shibam, Socotra, Ta'izz, Yemeni Coastal Plains, Yemeni Highlands, Yemeni Mountains, Zabid.
Let's look now what weather you can expect here. (Warning: As we don't have reliable data for this country, we use data from nearby locations for these statistics.) The warmest month here is July, the average maximum temperature is 44.2 ℃ (111.56 ℉). The average minimum temperature in this month is 27.3 ℃ (81.14 ℉). The coldest month here is January, the average maximum temperature is 27.5 ℃ (81.5 ℉). The average minimum temperature in this month is 10.4 ℃ (50.72 ℉). The most rainy month here is April, the average number of rainy days is 3.4. The least rainy month here is November, the average number of rainy days is 0.1. 
When travelling to some places in Yemen, always consider the altitude of the the place as well. The highest point here is Jabal an Nabi Shu'ayb (3666 m) and the lowest point is Arabian Sea (0 m). So there are huge differences in altitudes in this country and the weather is very different in them therefore. Keep in mind, that the temperature usually decreases by 1.2 - 1.9 ℃ (2.2 - 3.5 ℉) per 200 m (656 ft), depending on the other conditions. (And we should add, that in the very special condition named thermal inversion even the temperature may be higher in higher altitudes.)
Typical (usual) weather in Yemen in January is this: The average highest temperature in Yemen in January is 27.5 ℃ (81.5 ℉). The average lowest temperature is 10.4 ℃ (50.72 ℉). At the beginning of January you can expect higher temperatures, the average highest temperature is around 27.85 ℃ (82.13 ℉). At the end of January you can expect higher temperatures, the average highest temperature is around 29.5 ℃ (85.1 ℉). The average number of rainy days in January is 0.3. The average rainfall is 1 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 11:06 (hours and minutes), in the middle of the month 11:11 and at the end of the month 11:21.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.
Typical (usual) weather in Yemen in February is this: The average highest temperature in Yemen in February is 31.5 ℃ (88.7 ℉). The average lowest temperature is 14.1 ℃ (57.38 ℉). At the beginning of February you can expect lower temperatures, the average highest temperature is around 29.5 ℃ (85.1 ℉). At the end of February you can expect higher temperatures, the average highest temperature is around 33.25 ℃ (91.85 ℉). The average number of rainy days in February is 1. The average rainfall is 2.9 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 11:21 (hours and minutes), in the middle of the month 11:34 and at the end of the month 11:48.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in March is this: The average highest temperature in Yemen in March is 35 ℃ (95 ℉). The average lowest temperature is 17.4 ℃ (63.32 ℉). At the beginning of March you can expect lower temperatures, the average highest temperature is around 33.25 ℃ (91.85 ℉). At the end of March you can expect higher temperatures, the average highest temperature is around 36.45 ℃ (97.61 ℉). The average number of rainy days in March is 2.4. The average rainfall is 17.6 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 11:48 (hours and minutes), in the middle of the month 12:02 and at the end of the month 12:17.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in April is this: The average highest temperature in Yemen in April is 37.9 ℃ (100.22 ℉). The average lowest temperature is 21.1 ℃ (69.98 ℉). At the beginning of April you can expect lower temperatures, the average highest temperature is around 36.45 ℃ (97.61 ℉). At the end of April you can expect higher temperatures, the average highest temperature is around 39.3 ℃ (102.74 ℉). The average number of rainy days in April is 3.4. The average rainfall is 19 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:17 (hours and minutes), in the middle of the month 12:32 and at the end of the month 12:45.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in May is this: The average highest temperature in Yemen in May is 40.7 ℃ (105.26 ℉). The average lowest temperature is 24 ℃ (75.2 ℉). At the beginning of May you can expect lower temperatures, the average highest temperature is around 39.3 ℃ (102.74 ℉). At the end of May you can expect higher temperatures, the average highest temperature is around 41.75 ℃ (107.15 ℉). The average number of rainy days in May is 0.8. The average rainfall is 3.5 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:45 (hours and minutes), in the middle of the month 12:56 and at the end of the month 13:05.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in June is this: The average highest temperature in Yemen in June is 42.8 ℃ (109.04 ℉). The average lowest temperature is 25.2 ℃ (77.36 ℉). At the beginning of June you can expect lower temperatures, the average highest temperature is around 41.75 ℃ (107.15 ℉). At the end of June you can expect higher temperatures, the average highest temperature is around 43.5 ℃ (110.3 ℉). The average number of rainy days in June is 0.4. The average rainfall is 4.7 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 13:05 (hours and minutes), in the middle of the month 13:09 and at the end of the month 13:09.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in July is this: The average highest temperature in Yemen in July is 44.2 ℃ (111.56 ℉). The average lowest temperature is 27.3 ℃ (81.14 ℉). At the beginning of July you can expect lower temperatures, the average highest temperature is around 43.5 ℃ (110.3 ℉). At the end of July you can expect lower temperatures, the average highest temperature is around 43.2 ℃ (109.76 ℉). The average number of rainy days in July is 0.7. The average rainfall is 5.3 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 13:09 (hours and minutes), in the middle of the month 13:05 and at the end of the month 12:56.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in August is this: The average highest temperature in Yemen in August is 42.2 ℃ (107.96 ℉). The average lowest temperature is 27.1 ℃ (80.78 ℉). At the beginning of August you can expect higher temperatures, the average highest temperature is around 43.2 ℃ (109.76 ℉). At the end of August you can expect lower temperatures, the average highest temperature is around 41.1 ℃ (105.98 ℉). The average number of rainy days in August is 1.5. The average rainfall is 7.1 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:56 (hours and minutes), in the middle of the month 12:44 and at the end of the month 12:31.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in September is this: The average highest temperature in Yemen in September is 40 ℃ (104 ℉). The average lowest temperature is 23.9 ℃ (75.02 ℉). At the beginning of September you can expect higher temperatures, the average highest temperature is around 41.1 ℃ (105.98 ℉). At the end of September you can expect lower temperatures, the average highest temperature is around 38.1 ℃ (100.58 ℉). The average number of rainy days in September is 0.5. The average rainfall is 2 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:31 (hours and minutes), in the middle of the month 12:17 and at the end of the month 12:02.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in October is this: The average highest temperature in Yemen in October is 36.2 ℃ (97.16 ℉). The average lowest temperature is 19.4 ℃ (66.92 ℉). At the beginning of October you can expect higher temperatures, the average highest temperature is around 38.1 ℃ (100.58 ℉). At the end of October you can expect lower temperatures, the average highest temperature is around 33.55 ℃ (92.39 ℉). The average number of rainy days in October is 0.3. The average rainfall is 1.7 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 12:02 (hours and minutes), in the middle of the month 11:48 and at the end of the month 11:34.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in November is this: The average highest temperature in Yemen in November is 30.9 ℃ (87.62 ℉). The average lowest temperature is 15.1 ℃ (59.18 ℉). At the beginning of November you can expect higher temperatures, the average highest temperature is around 33.55 ℃ (92.39 ℉). At the end of November you can expect lower temperatures, the average highest temperature is around 29.55 ℃ (85.19 ℉). The average number of rainy days in November is 0.1. The average rainfall is 0.5 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 11:34 (hours and minutes), in the middle of the month 11:21 and at the end of the month 11:12.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Yemen in December is this: The average highest temperature in Yemen in December is 28.2 ℃ (82.76 ℉). The average lowest temperature is 11.6 ℃ (52.88 ℉). At the beginning of December you can expect higher temperatures, the average highest temperature is around 29.55 ℃ (85.19 ℉). At the end of December you can expect lower temperatures, the average highest temperature is around 27.85 ℃ (82.13 ℉). The average number of rainy days in December is 0.1. The average rainfall is 1.8 mm (look here, what this number means). When planning your travel, please, keep in mind, that actual weather may differ from these average values. The length of the day at the beginning of this month is approximately 11:12 (hours and minutes), in the middle of the month 11:06 and at the end of the month 11:05.This data is approximate because we do not have exact data for this country. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.