Most people arrive in Puri with a vague sense of when to come, and the vague sense is often wrong. The city has genuinely distinct seasons and the difference between them is large enough that a trip planned for the wrong month can be miserable.
The pleasant window runs from around October to February. This is the season most people have in mind when they think of Puri: warm days, cool evenings, and a sea that is pleasant to sit beside in the morning. If you have any flexibility in your dates, this is the period to aim for. It is also, unsurprisingly, the busiest and most expensive period, and it includes the tail end of the summer as well as the New Year period when the beach becomes the busiest part of Puri.
March and April are hot but not yet punishing, and they are quieter. The trade-off is a strong sun and a sea that is rough enough to be unpleasant. Many guests use this window to focus on the temple and the old city rather than the beach, which is a reasonable way to spend a hotter month in Puri.
May and June are the difficult months. Temperature is only part of it. The combination of high heat, humidity coming off the Bay of Bengal, and the reflection off stone and sand makes it genuinely difficult to spend hours outdoors, particularly in the afternoons. The sea is at its roughest. If your dates are fixed to this period, plan more of your time indoors, plan your temple visits for the early morning and the evening, and expect to spend a good deal of the day in your room.
The monsoon runs from roughly June to September and divides opinion sharply. The humidity stays high, and the sea is often unsafe and muddy, which is the strongest argument against this period. The counter-argument is real: Odisha gets a large share of its annual rainfall in a compressed period, the landscape greens up dramatically, prices drop, and the city empties out. Odisha also genuinely needs that rain, and there are waterlogged days when Grand Road becomes difficult to navigate. If you come in the monsoon, come expecting rain rather than hoping for a gap in it.
Then there is the festival calendar, which overrides all of the above. Rath Yatra in June and July is the single largest draw on the city, and the Jagannath temple, Grand Road, and the beach all operate under their own arrangements during the period. If you are travelling for Rath Yatra specifically, plan the accommodation months in advance and accept that you will be in dense crowds. Puri's own calendar is not the only consideration: a large number of visitors extend their trip to Konark and Chilika at the same time, and those places will be full too.
Two practical notes. First, book early for the good window. Puri is not a destination where you can reliably find a room on arrival in November or during Rath Yatra. Second, if you tell us your dates before you book, we will tell you honestly what the season will feel like rather than after you have already committed.