Check out this handy chart for all the deets
Date Location Daytime Temps (°F / °C) Nighttime Temps (°F / °C) Weather Conditions March 21-24 Kathmandu, Nepal 55-80°F (13-27°C) 40-55°F (5-13°C) Pleasant, dry air, cool mornings March 24-26 Chitwan National Park, Nepal 65-90°F (18-32°C) 55-70°F (13-21°C) Warm, humid, chance of light rain March 26-28 Pokhara, Nepal 60-85°F (16-29°C) 50-65°F (10-18°C) Pleasant, mild mornings March 28-29 Kathmandu, Nepal 55-80°F (13-27°C) 40-55°F (5-13°C) Similar to earlier stay, dry & comfortable March 29-30 Thimphu, Bhutan 45-70°F (7-21°C) 30-45°F (-1-7°C) Crisp, dry, cool at night March 30-31 Punakha, Bhutan 55-80°F (13-27°C) 40-60°F (5-16°C) Warmer than Thimphu, blooming spring flowers March 31-April 2 Paro, Bhutan 50-75°F (10-24°C) 30-50°F (-1-10°C) Crisp mornings, sunny afternoons April 2-3 Agra, India 70-95°F (21-35°C) 60-75°F (16-24°C) Hot, dry, intense sun April 3-6 Delhi, India 75-100°F (24-38°C) 65-80°F (18-27°C) Very warm, dusty, occasional rain showers