San Francisco, Guatemala has a dry and hot summer season from March to May with temperatures often reaching up to 40°C. The months of June, July, August, and September are characterized by relatively stable high temperatures around 27°C, with minimal fluctuation between day and night temperatures. The cooler winter months of November and December bring slightly lower temperatures, but still averaging around 24°C. April is the warmest month on average, while October marks a slight decrease in temperature before the cooler winter sets in. Overall, San Francisco's climate is marked by mild winters and hot summers with little seasonal variation.