Cusco · Month comparison

September vs May

May ranks #1 overall vs September at #3. The dry season arrives — clear skies, the Inca Trail fully open, and Machu Picchu at its most reliably beautiful.

Cusco September — the multicoloured striped slopes of Rainbow Mountain (Vinicunca) in the Andes near Cusco under dramatic skies

September

#3 of 12 months

Best match

The ideal sweet spot — dry-season weather, crowds retreating, Inca Trail permits available, and prices back to moderate.

  • ↑September retains essentially the same excellent dry-season weather as July–August (only 40mm rain, 7.5 sunshine hours) but the school holiday crowds have returned home and prices drop significantly
  • ↑Machu Picchu timed-entry slots are much more easily booked; the site is quieter than peak season and the experience is meaningfully more atmospheric
Cusco May — Plaza de Armas with the cathedral and dramatic clouds over the ancient colonial square

May

#1 of 12 months

Best match

The dry season arrives — clear skies, the Inca Trail fully open, and Machu Picchu at its most reliably beautiful.

  • ↑Dry season proper begins: 44mm of rain is minimal, skies are consistently clear, and the mountain views from Machu Picchu and the Sacred Valley are sharp and unobscured
  • ↑Inca Trail permits are still available in May (unlike the July–August peak when they sell out months ahead) — the optimal window for hiking with full conditions and manageable crowds
FactorSeptemberMay
Weather score
9
9
Value score
5
6
Crowd score
5
6
Events score
5
7
Atmosphere
8
8
Avg high temp20°C20°C
Monthly rain40mm44mm
Daily sunshine7.5hrs7.8hrs

September trade-offs

  • ↓The very tail of the dry season; by late September occasional afternoon clouds begin to build, hinting at the transition — weather is still excellent but July clarity is starting to wane
  • ↓Hotel prices, while lower than July–August, are still notably higher than the wet-season trough; September is a sweet spot, not a bargain
  • ↓Altitude acclimatisation is unavoidable at 3,400m — budget at least a full day in Cusco before any physical activity, however fit you are

May trade-offs

  • ↓Nights are cold (4°C) and can catch visitors off guard; altitude at 3,400m intensifies the chill — warm layers are non-negotiable
  • ↓Prices begin rising as the dry season is recognised; May is still moderate but more expensive than the wet-season months
  • ↓Inca Trail permits for the popular Classic Trail sell out in advance — book at least two to three months ahead for May departures
See all 12 months for Cusco →September in detail →May in detail →
Scores compare months within Cusco. Climate data: Open Meteo ERA5 30-year normals (1991–2020). Methodology →