Climbing Kilimanjaro in May: Rainy Season Realities & Late-May Window

May is the month most guides will tell you to avoid on Kilimanjaro. The long rains are still present, the trails are muddy, and the summit can vanish behind clouds for days at a stretch. In our 800+ expeditions to the roof of Africa, we have guided climbers through every May since 2009 — and what we have learned is more nuanced than a simple "don't go." The reality is that May is a month of two halves. Early May is genuinely wet and challenging. Late May — roughly the final 10 days — sees rainfall dropping sharply as the long rainy season exhausts itself. If you time it right, you get an empty mountain, lower prices, and conditions that are surprisingly cooperative. This guide breaks down exactly what May climbing looks like: weather data from our own expeditions, honest success rate numbers, which route handles the rain, what to pack, and how to decide whether May is right for your Kilimanjaro goal.

May Weather on Kilimanjaro: The Full Picture

May falls squarely within the "long rains" — the primary wet season in East Africa that runs from mid-March through late May. The moisture is driven by the Intertropical Convergence Zone (ITCZ) passing over the region, pulling warm, saturated air from the Indian Ocean directly into the mountain's southeastern slopes. This is not occasional drizzle. Early May on Kilimanjaro's southern flanks can produce sustained rain for 6-8 hours, transforming forest trails into streams and moorland paths into mud.

But the mountain is not uniformly wet. The northern slopes receive roughly 40% less rainfall than the south, and the precipitation decreases markedly above 4,000m. By the alpine desert zone, what falls as rain below often arrives as light snow or dry, wind-driven sleet that rarely accumulates.

Temperature by Elevation Zone

• Rainforest zone (1,800-2,800m)Warm and very humid at 15-24°C during the day. The canopy traps moisture, and everything feels damp. Leeches are active. Trail surfaces are slippery with organic matter. Rainfall at this altitude averages 250-350mm for the month, with the heaviest falls between May 1-18.
• Heath and moorland (2,800-4,000m)Cooler at 5-14°C during the day, dropping to -1 to 4°C at night. Cloud cover is persistent, limiting visibility to 50-200m on many afternoons. The giant heather drips constantly. Camps can feel oppressively grey for 2-3 consecutive days in early May.
• Alpine desert (4,000-4,700m)Daytime temperatures of 0-7°C with occasional breaks of strong sunshine through cloud gaps. Nighttime drops to -5 to -12°C at Barafu or Kibo Hut. Wind chill is a factor, particularly on exposed ridges. Snow patches from accumulated precipitation are common on Kibo's upper slopes.
• Summit zone (4,700-5,895m)Summit night temperatures of -8 to -18°C, with wind chill pushing perceived temperatures below -25°C. The crater rim may carry fresh snow. Glaciers show more ice coverage than during the dry months, and the summit views — when the clouds part — reveal a dramatically white, arctic landscape that few climbers ever witness.

Rainfall Data: Early May vs Late May

This distinction matters enormously for planning. Our expedition data shows a clear split:

• May 1-20Average rainfall of 180-250mm in the forest zone. Rain falls on 15-18 of these 20 days, typically starting between 11am and 1pm and continuing through the evening. Above 3,500m, precipitation occurs on 8-12 days, often as mist and drizzle rather than heavy rain.
• May 21-31Rainfall drops sharply to 40-80mm for the final 10 days. Rain frequency falls to 5-7 days, showers are shorter (1-2 hours), and mornings are frequently clear. Above 3,500m, you may experience only 2-3 precipitation events. By May 28-31, conditions can closely resemble early June — the start of the dry season.

For the complete rainfall and temperature dataset, see our Kilimanjaro weather guide. The bottom line: if you are set on May, start your trek around May 20-22 so that your summit attempt falls in the final days of the month when conditions have largely stabilized.

Crowd Levels: The Emptiest Month on the Mountain

This is May's singular advantage, and it is not a small one. Kilimanjaro receives approximately 1,200-1,800 climbers in May — compared to 8,000-10,000 in August and 6,000-8,000 in January. That is a fraction of peak-season traffic. We have guided May treks where our group did not see another team for an entire day on the Rongai Route. Camps that hold 30-50 tents in July had 3-4 tents in May.

The solitude transforms the experience. There is no queue at Gilman's Point. There is no jostling for space at Stella Point for sunrise photographs. The mountain feels wild and untouched in a way that is impossible during the high season. For climbers who value wilderness experience over comfort, May offers something that money cannot buy in July.

Pricing in May

Operators discount May significantly. Park fees remain fixed by KINAPA at $70/day for climbers over 16, but operator charges — guides, porters, food, equipment, transport — are typically 15-25% lower than peak-season rates. Hotels in Moshi and Arusha also run low-season pricing. A 7-day Rongai trek that costs $2,800-3,200 in July may run $2,200-2,600 in May. That saving funds a safari extension or a few nights on Zanzibar.

Success Rates: Honest Numbers

We will not sugarcoat this. Our May summit success rate across all routes averages 70-80%, with a clear split between early and late May:

• May 1-15 treks65-72% success rate. The primary cause of turnarounds is not altitude sickness but weather-related issues — hypothermia risk from prolonged wet conditions, trail closures on exposed sections, and climber morale collapse after 3-4 consecutive days of rain.
• May 16-31 treks78-85% success rate. As the rains taper, conditions become much more manageable. Treks starting around May 20 that reach the summit on May 26-28 often report dry summit nights and clear sunrise views.

Compare this to the 90-95% we achieve in July-August on 7+ day routes. The gap is real but narrower than most people assume, especially for late-May departures. The climbers who struggle in May are almost always those who underestimated the conditions and brought inadequate rain gear.

Best Route for May: Rongai Is the Clear Winner

The Rongai Route approaches Kilimanjaro from the north, starting near the Kenya border. This matters enormously in May because the long rains are driven by southeastern trade winds from the Indian Ocean. The northern slopes sit in a rain shadow — they receive roughly 40% less precipitation than the southern Machame or Marangu approaches.

Why Rongai Works in May

• Drier approachThe northern forest zone receives 100-150mm in May vs 250-350mm on the southern face. The trail surface is better drained — volcanic soil rather than the clay-heavy southern paths.
• Wind shelterThe route traverses the lee side of Kibo, meaning wind exposure is lower during the critical alpine desert and summit push.
• Gradual gradientRongai's gentle incline means less energy expenditure on slippery terrain, reducing the compounding fatigue that wet conditions create.
• Fewer river crossingsThe Machame and Lemosho routes cross several drainage channels that swell during the rains. Rongai has minimal water crossings.

We recommend the 7-day Rongai itinerary for May climbers — the extra acclimatization day provides a weather buffer and improves summit success rate by approximately 10% compared to the 6-day version.

Routes to Avoid in May

The Western Breach route on the Machame side should not be attempted in May. Rockfall risk increases with freeze-thaw cycles from wet conditions, and the scrambling sections become hazardous when iced over. The Umbwe Route, already the steepest on the mountain, becomes treacherous with rain-soaked roots and loose scree. Marangu's concrete-box huts offer some shelter from rain but the "Coca-Cola Route" nickname does not extend to weatherproofing — the huts are basic, and the trail itself is a muddy corridor in May.

What to Pack: May-Specific Gear

May demands more from your kit than any other month. The standard Kilimanjaro packing list applies, but with these critical additions:

• Waterproof layers (non-negotiable)A high-quality hardshell jacket with taped seams and a hood that fits over a helmet. Budget rain jackets with DWR coating will fail after sustained exposure. We recommend Gore-Tex or eVent fabrics rated for mountaineering — not hiking-grade water resistance.
• Waterproof trousersFull-zip side openings so you can pull them on over boots without sitting in mud. Carry these in your daypack, not your duffel.
• GaitersKnee-high gaiters keep mud and water out of your boots. In May, ankle-high gaiters are insufficient. Mud on the Machame Gate trail can reach mid-shin depth.
• Pack cover + dry bagsDouble protection. The pack cover handles rain; the dry bags inside protect sleeping bag and spare clothing if the cover fails. We issue our climbers 20-litre dry bags for summit night clothing.
• Extra socksBring 6-8 pairs of merino wool hiking socks instead of the usual 4-5. Wet feet are the fastest route to blisters and misery.
• Quick-dry base layersCotton is banned in May. Merino wool or synthetic base layers that dry overnight are essential.
• Hand and toe warmersThe combination of wet conditions and sub-zero summit night temperatures makes chemical warmers more valuable in May than in any other month.

The Case For and Against Climbing in May

Reasons to Climb in May

• SolitudeThe mountain is yours. We have had clients describe their May summit as "the most remote I have ever felt — standing on the roof of Africa completely alone."
• Cost15-25% savings on operator fees, lower hotel rates, better flight deals.
• Dramatic sceneryThe mountain wears its most dramatic outfit in May — fresh snow on the summit, lush green lower slopes, waterfalls at full force, and cloud formations that create ethereal lighting for photography.
• Character testThere is a raw honesty to climbing in tough conditions. No one climbs Kilimanjaro in May by accident. Everyone on the trail has made a deliberate choice, and that shared commitment creates a different kind of camaraderie among climbers and guides.

Reasons to Avoid May

• Lower success ratesEven late May sits below peak-season numbers. If summiting is your absolute priority and you have no flexibility, July-October is the safer bet.
• DiscomfortMultiple days of wet conditions test morale. If you are not comfortable being uncomfortable, May will not be enjoyable.
• Gear costProper waterproof mountaineering gear is expensive. The savings on trek cost may be partially offset by gear investment if you do not already own high-quality rain layers.
• Limited viewsCloud cover can obscure the sweeping savanna vistas that are part of the Kilimanjaro experience. Summit sunrise is not guaranteed.

For more context on seasonal timing, see our best time to climb Kilimanjaro guide and our specific Kilimanjaro rainy season breakdown.

Combining May Kilimanjaro with Safari

May is also low season for Tanzania's northern circuit safari parks — Serengeti, Ngorongoro, Tarangire, and Lake Manyara. The Serengeti's wildebeest herds are in the central/western corridor during May, the calving season is winding down, and the grass is lush and green. Game viewing is excellent because fewer vehicles are competing for sightings. We regularly build 3-4 day safari extensions for our May Kilimanjaro clients, and the combined trip represents outstanding value compared to a July-August equivalent.

Our May Climbing Recommendation

We run a limited number of departures in May — typically 2-3 groups, all on the Rongai Route, all on 7-day itineraries. We time departures so that summit attempts fall between May 25-31, when the rain has typically broken. Our guides carry additional weatherproofing supplies, and our pre-trek briefings are more extensive in May, covering wet-weather technique and morale management.

If you are an experienced hiker who thrives in tough conditions, values solitude, and understands that a weather-affected trek is still a legitimate mountaineering achievement, May is a genuinely rewarding time to climb. If you are a first-time high-altitude trekker or someone who needs sunshine to stay motivated, wait for June or July.

Browse our Kilimanjaro route options or read our June guide to compare conditions as the dry season begins.

Frequently Asked Questions: Climbing Kilimanjaro in May

Is May a good time to climb Kilimanjaro?

May is not ideal for most climbers, but late May (May 20-31) can be surprisingly good. The long rains taper off sharply in the final 10 days, crowds are at their annual minimum, and prices are 15-25% lower. We recommend May only for experienced hikers who are comfortable with wet conditions and willing to invest in proper waterproof gear. If you time a 7-day Rongai trek to summit around May 26-28, you have a realistic 78-85% chance of reaching Uhuru Peak.

What is the success rate on Kilimanjaro in May?

Overall May success rates average 70-80%. Early May (1st-15th) sees 65-72% due to persistent rain. Late May (16th-31st) improves to 78-85% as conditions stabilize. By comparison, peak dry season (July-August) success rates on guided 7-day treks reach 90-95%. The gap is meaningful but not as large as many assume, especially on the drier Rongai Route in late May.

Which is the best route for Kilimanjaro in May?

The Rongai Route is the clear best choice. It approaches from the north, receiving roughly 40% less rainfall than southern routes like Machame and Lemosho. The volcanic soil drains better, wind exposure is lower, and the gradual gradient reduces the impact of slippery trail conditions. We exclusively run May departures on the 7-day Rongai itinerary.

How much does it cost to climb Kilimanjaro in May?

Expect to save 15-25% on operator fees compared to peak season. A 7-day guided Rongai trek typically runs Expect to save 15-25% on operator fees compared to peak season. A 7-day guided Rongai trek typically runs $2,200-2,600 in May versus $2,800-3,200 in July-August. KINAPA park fees ($70/day for adults) are fixed year-round. Hotels, ,200-2,600 in May versus Expect to save 15-25% on operator fees compared to peak season. A 7-day guided Rongai trek typically runs $2,200-2,600 in May versus $2,800-3,200 in July-August. KINAPA park fees ($70/day for adults) are fixed year-round. Hotels, ,800-3,200 in July-August. KINAPA park fees ($70/day for adults) are fixed year-round. Hotels, flights to Kilimanjaro Airport, and post-climb safaris are also cheaper during May's low season.

What weather should I expect on Kilimanjaro in May?

Early May brings sustained rainfall — 180-250mm in the forest zone, rain on 15-18 of 20 days. Late May drops to 40-80mm with rain on only 5-7 days. Temperatures range from 15-24°C in the rainforest to -8 to -18°C at the summit. Above 4,000m, precipitation often falls as snow or sleet. Cloud cover is persistent, especially in the mornings, but late May afternoons increasingly feature clearing skies.

Should I avoid Kilimanjaro entirely during the rainy season?

Not necessarily. The rainy season covers March-May (long rains) and November (short rains). March and April are the months to genuinely avoid — relentless rain and minimal clearing windows. Late May is a transitional window where conditions improve daily. November's short rains are less intense than the long rains. Each wet month has different characteristics, and a blanket "avoid rainy season" rule oversimplifies the reality.

Can I combine a May Kilimanjaro climb with a safari?

Absolutely — and it is excellent value. May is low season for Tanzania's safari circuit. The Serengeti wildebeest are in the central/western corridor, Ngorongoro Crater has fewer vehicles, and lodge rates drop significantly. We regularly add 3-4 day safari packages after May climbs, and the combined trip costs 20-30% less than the same itinerary in August.

What extra gear do I need for a May climb?

Beyond the standard packing list, May requires: a Gore-Tex or eVent hardshell jacket (not budget DWR-coated), full-zip waterproof trousers, knee-high gaiters, a pack cover plus internal dry bags, 6-8 pairs of merino socks (instead of 4-5), and chemical hand/toe warmers. Cotton clothing should be completely excluded. The investment in quality waterproof gear is the single biggest factor in May comfort and safety.

How cold is the summit in May?

Summit night temperatures range from -8 to -18°C, with wind chill pushing perceived temperatures below -25°C. Fresh snow on the crater rim is common in May, and ice conditions on the final ascent from Stella Point to Uhuru Peak can require more careful footing than dry-season climbs. The cold itself is comparable to other months — it is the combination of cold plus residual moisture from lower elevations that makes May summit nights feel harsher.

Is Marangu Route a good option in May because of the huts?

The logic seems sound — huts provide shelter from rain — but in practice, Marangu is not a good May choice. The route runs entirely along the southeastern face, which receives the heaviest rainfall. The trail becomes a muddy corridor, and the huts, while providing a roof, are basic dormitory-style structures without heating or drying facilities. Wet gear stays wet. The Rongai Route is drier overall, and well-maintained tents with vestibules for gear storage are more practical than Marangu's huts for managing wet-weather climbing.

How many people climb Kilimanjaro in May?

Approximately 1,200-1,800 climbers attempt Kilimanjaro in May, making it the quietest month on the mountain. In peak season (July-August), that number reaches 8,000-10,000. On the Rongai Route in late May, it is common to see only 2-3 other groups across the entire trek. Camps are virtually empty, and the summit is often deserted at sunrise.

When exactly do the long rains end on Kilimanjaro?

There is no fixed date — it varies by year. In our experience across 15+ years of guiding, the long rains typically break between May 18 and May 28. Some years see an abrupt stop, with clear skies from one day to the next. Other years show a gradual tapering over 7-10 days. We monitor weather patterns closely and communicate conditions to booked clients in real time so they can prepare accordingly.