Peak season ex-India isn't one event — it's three overlapping waves: the monsoon, the festive production cycle around Diwali, and the West's year-end stocking race, with Chinese Golden Week throwing blank sailings into the middle. The shippers who win Q4 booked it in July.
The calendar, month by month
Forecast & carrier allocations
Jul – AugLock space commitments with carriers before spot rates spike — GRIs cluster in announcements effective the 1st and 15th from late summer. Monsoon (June–September) is already disrupting West-coast berthing windows at Nhava Sheva and Mundra; build slack into cutoffs. Watch 40ft HC equipment supply at North Indian ICDs (Tughlakabad, Ludhiana, Dadri) — the recurring August–October pinch.
The pre-peak golden window
SeptemberShip high-volume, non-perishable holiday stock now — before Chinese Golden Week (Oct 1–7) idles Chinese factories and triggers pre-GW space squeezes plus post-GW blank sailings on the mainline strings that also serve Indian ports. With Cape routing still adding ~10–14 days to Europe, September ocean departures are effectively your last comfortable Christmas-shelf window.
Peak crunch & premium surcharges
Oct – NovDiwali compresses Indian production on both sides — overtime sprints before, worker leave after. Expect ocean roll risk, Peak Season Surcharges of roughly $300–1,000 per 40ft in tight windows, and the air-freight crunch building to its October–mid-December high (Europe lanes pushing $5–6+/kg). Triage: air-inject only high-margin SKUs at genuine stockout risk; everything else holds its ocean booking.
Last-mile clean-up & returns prep
DecemberShift focus to destination-side flow: domestic intermodal routing for arrived stock, forward-positioning for the post-holiday returns wave, and January's reverse-logistics plan. Quietly book Jan–Feb capacity too — the pre-Chinese New Year ripple is the season's final aftershock.
The monsoon variable nobody budgets
From June to September, the southwest monsoon brings work stoppages during heavy rain and lightning at western ports, swell-driven berthing delays, and slower inland trucking — with cyclone-season closures possible on the Arabian Sea early and the Bay of Bengal (Chennai, Vizag, Kolkata) late in the year. None of it is dramatic individually; collectively it costs 2–5 days exactly when your margin for error is thinnest. The fix is unglamorous: earlier cutoffs, covered/CFS handling for moisture-sensitive LCL, and ETAs read from live data rather than published schedules.