Do you need to know, when is the best time to go to Peru? Then you should take a look here, what weather you can expect there during the year.
The climate of Peru is varied. You can expect tropical weather in east and dry desert weather in west. In Andes weather is temperate or frigid. The eastern lowlands have an equatorial climate with hot weather and rain throughout the whole year.
When speaking about the usual weather in this state, the information is relevant for example for these popular places: Abancay, Aguas Calientes, Aguaytía, Altiplano, Andagua, Andahuaylas, Andahuaylillas, Arequipa, Atalaya, Ayacucho, Ballestas Islands, Barranca, Caballococha, Cachora, Cajabamba, Cajamarca, Callao, Camaná, Caral, Caraz, Casma, Celendín, Central Coast, Central Sierra, Chachapoyas, Chahuay, Chavín de Huántar, Chicama, Chiclayo, Chimbote, Chinchero, Choquequirao, Chota, Chucuito, Churin, Colca Canyon, Cordillera Blanca, Cutimbo, Cuzco, Gocta, Huacachina, Huancavelica, Huancayo, Huanchaco, Huaraz, Huascarán National Park, Huánuco, Ica, Iquitos, Isla Amantani, Isla Taquile, Jaén, Juanjuí, Juliaca, Kiteni, Kuelap, La Merced, La Rinconada, Leimebamba, Lima, Los Organos, Machu Picchu, Madre de Dios, Manú National Park, Maras, Mollepata, Moyobamba, Máncora, Nazca, Northern Coast, Northern Sierra, Ollantaytambo, Oxapampa, Pantoja, Paracas, Patacancha, Paucartambo, Peruvian Amazon, Pichanaki, Pisac, Pisco, Piura, Pozuzo, Pucallpa, Puerto Maldonado, Puerto Ocopa, Puno, Quillabamba, Rio Abiseo National Park, Sacred Valley of the Incas, San Martín, Santa Rosa Island, Santa Teresa, Satipo, Sauce, Sechin, Sepahua, Sillustani, Southern Coast, Southern Sierra, Tacna, Tarapoto, Tarma, Tipón, Tocache, Trujillo, Tumbes, Uro Islands, Urubamba, Villa Rica, Yucay, Yurimaguas, Zorritos.
Let's look now what weather you can expect in the area around the capital and in many other cities. The warmest month here is February, the average maximum temperature is 26.5 ℃ (79.7 ℉). The average minimum temperature in this month is 20 ℃ (68 ℉). The coldest month here is August, the average maximum temperature is 18.7 ℃ (65.66 ℉). The average minimum temperature in this month is 14.7 ℃ (58.46 ℉). 
When travelling to some places in Peru, always consider the altitude of the the place as well. The highest point here is Nevado Huascaran (6746 m) and the lowest point is Pacific Ocean (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 Peru in January is this: The average highest temperature in Peru in January is 26.4 ℃ (79.52 ℉). The average lowest temperature is 19.2 ℃ (66.56 ℉). At the beginning of January you can expect lower temperatures, the average highest temperature is around 25.45 ℃ (77.81 ℉). At the end of January you can expect higher temperatures, the average highest temperature is around 26.45 ℃ (79.61 ℉). The average rainfall is 0.9 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 12:49 (hours and minutes), in the middle of the month 12:44 and at the end of the month 12:38.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in February is this: The average highest temperature in Peru in February is 26.5 ℃ (79.7 ℉). The average lowest temperature is 20 ℃ (68 ℉). At the beginning of February you can expect lower temperatures, the average highest temperature is around 26.45 ℃ (79.61 ℉). At the end of February you can expect lower temperatures, the average highest temperature is around 26.1 ℃ (78.98 ℉). The average rainfall is 0.3 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 12:38 (hours and minutes), in the middle of the month 12:29 and at the end of the month 12:19.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in March is this: The average highest temperature in Peru in March is 25.7 ℃ (78.26 ℉). The average lowest temperature is 19.2 ℃ (66.56 ℉). At the beginning of March you can expect higher temperatures, the average highest temperature is around 26.1 ℃ (78.98 ℉). At the end of March you can expect lower temperatures, the average highest temperature is around 25.05 ℃ (77.09 ℉). The average rainfall is 4.8 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 12:19 (hours and minutes), in the middle of the month 12:09 and at the end of the month 11:59.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in April is this: The average highest temperature in Peru in April is 24.4 ℃ (75.92 ℉). The average lowest temperature is 18 ℃ (64.4 ℉). At the beginning of April you can expect higher temperatures, the average highest temperature is around 25.05 ℃ (77.09 ℉). At the end of April you can expect lower temperatures, the average highest temperature is around 22.9 ℃ (73.22 ℉). The average rainfall is 0 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 11:59 (hours and minutes), in the middle of the month 11:50 and at the end of the month 11:41.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.
Typical (usual) weather in Peru in May is this: The average highest temperature in Peru in May is 21.4 ℃ (70.52 ℉). The average lowest temperature is 16.2 ℃ (61.16 ℉). At the beginning of May you can expect higher temperatures, the average highest temperature is around 22.9 ℃ (73.22 ℉). At the end of May you can expect lower temperatures, the average highest temperature is around 20.85 ℃ (69.53 ℉). The average rainfall is 0.1 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 11:41 (hours and minutes), in the middle of the month 11:33 and at the end of the month 11:28.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in June is this: The average highest temperature in Peru in June is 20.3 ℃ (68.54 ℉). The average lowest temperature is 15.5 ℃ (59.9 ℉). At the beginning of June you can expect higher temperatures, the average highest temperature is around 20.85 ℃ (69.53 ℉). At the end of June you can expect lower temperatures, the average highest temperature is around 19.55 ℃ (67.19 ℉). The average rainfall is 0.3 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 11:28 (hours and minutes), in the middle of the month 11:25 and at the end of the month 11:25.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in July is this: The average highest temperature in Peru in July is 18.8 ℃ (65.84 ℉). The average lowest temperature is 15 ℃ (59 ℉). At the beginning of July you can expect higher temperatures, the average highest temperature is around 19.55 ℃ (67.19 ℉). At the end of July you can expect lower temperatures, the average highest temperature is around 18.75 ℃ (65.75 ℉). The average rainfall is 0.3 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 11:25 (hours and minutes), in the middle of the month 11:28 and at the end of the month 11:34.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in August is this: The average highest temperature in Peru in August is 18.7 ℃ (65.66 ℉). The average lowest temperature is 14.7 ℃ (58.46 ℉). At the beginning of August you can expect higher temperatures, the average highest temperature is around 18.75 ℃ (65.75 ℉). At the end of August you can expect higher temperatures, the average highest temperature is around 18.8 ℃ (65.84 ℉). The average rainfall is 0.3 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 11:34 (hours and minutes), in the middle of the month 11:41 and at the end of the month 11:50.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in September is this: The average highest temperature in Peru in September is 18.9 ℃ (66.02 ℉). The average lowest temperature is 15.1 ℃ (59.18 ℉). At the beginning of September you can expect lower temperatures, the average highest temperature is around 18.8 ℃ (65.84 ℉). At the end of September you can expect higher temperatures, the average highest temperature is around 19.65 ℃ (67.37 ℉). 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 11:50 (hours and minutes), in the middle of the month 11:59 and at the end of the month 12:09.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in October is this: The average highest temperature in Peru in October is 20.4 ℃ (68.72 ℉). The average lowest temperature is 15.4 ℃ (59.72 ℉). At the beginning of October you can expect lower temperatures, the average highest temperature is around 19.65 ℃ (67.37 ℉). At the end of October you can expect higher temperatures, the average highest temperature is around 21.05 ℃ (69.89 ℉). The average rainfall is 0.2 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 12:09 (hours and minutes), in the middle of the month 12:19 and at the end of the month 12:29.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in November is this: The average highest temperature in Peru in November is 21.7 ℃ (71.06 ℉). The average lowest temperature is 16.2 ℃ (61.16 ℉). At the beginning of November you can expect lower temperatures, the average highest temperature is around 21.05 ℃ (69.89 ℉). At the end of November you can expect higher temperatures, the average highest temperature is around 23.1 ℃ (73.58 ℉). The average rainfall is 0 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 12:29 (hours and minutes), in the middle of the month 12:37 and at the end of the month 12:44.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.Typical (usual) weather in Peru in December is this: The average highest temperature in Peru in December is 24.5 ℃ (76.1 ℉). The average lowest temperature is 17.8 ℃ (64.04 ℉). At the beginning of December you can expect lower temperatures, the average highest temperature is around 23.1 ℃ (73.58 ℉). At the end of December you can expect higher temperatures, the average highest temperature is around 25.45 ℃ (77.81 ℉). The average rainfall is 0.3 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 12:44 (hours and minutes), in the middle of the month 12:48 and at the end of the month 12:49.These numbers above are valid primarily for the capital and the area around it. It is important to say, that the weather may differ significantly in different altitudes, especially in mountains.| Piura | temperature: - | highest temperature: 32 ℃ (89.6 ℉) | lowest temperature: 18 ℃ (64.4 ℉) | rainfall: 0.6mm | rainy days: - |
| Cajamarca | temperature: - | highest temperature: 22 ℃ (71.6 ℉) | lowest temperature: 6.1 ℃ (42.98 ℉) | rainfall: 70.9mm | rainy days: 0 |
| Lima | temperature: - | highest temperature: 24.5 ℃ (76.1 ℉) | lowest temperature: 17.8 ℃ (64.04 ℉) | rainfall: 0.3mm | rainy days: - |
| Arequipa | temperature: - | highest temperature: 22 ℃ (71.6 ℉) | lowest temperature: 7.7 ℃ (45.86 ℉) | rainfall: 4.3mm | rainy days: - |
| Cuzco | temperature: - | highest temperature: 19.7 ℃ (67.46 ℉) | lowest temperature: 6.8 ℃ (44.24 ℉) | rainfall: 123.6mm | rainy days: - |
| Iquitos | temperature: - | highest temperature: 31.1 ℃ (87.98 ℉) | lowest temperature: 22.8 ℃ (73.04 ℉) | rainfall: 304.8mm | rainy days: - |
| Trujillo | temperature: - | highest temperature: 24.1 ℃ (75.38 ℉) | lowest temperature: 16.2 ℃ (61.16 ℉) | rainfall: 0.1mm | rainy days: 0 |
| Tacna | temperature: - | highest temperature: 25.8 ℃ (78.44 ℉) | lowest temperature: 15.2 ℃ (59.36 ℉) | rainfall: 0.7mm | rainy days: 0 |