Highlight
 

• Extreme rains disrupt production cycles across producing hubs
   
• Hub Southern Thailand face heavy damage in peak months
   
• Indonesia and Malaysia face steeper late-year losses
   

Weather—or rather, climate change—set an unusually disruptive tone for Southeast Asia’s rubber-producing heartland in 2025, reshaping the region’s tapping rhythms, export cycles and market expectations even as the peak production months arrived. What began as a season expected to bring only moderate climatic variability quickly evolved into a year defined by overlapping ocean-atmosphere anomalies, relentless rainfall and a chain of supply shocks that rippled across Thailand, Indonesia, Malaysia and Vietnam.
 

The convergence of a lingering La Niña and a negative Indian Ocean Dipole—two climate forces that seldom peak simultaneously—supercharged monsoon systems across Thailand, Malaysia, Indonesia and Vietnam. Warm waters in the South China Sea and eastern Philippines acted as additional amplifiers, creating ideal conditions for unusually moisture-laden storms. Climate scientists described the year as one defined by near-perfect ingredients for extreme rainfall, and its agricultural imprint became visible quickest on the region’s rubber belt.
 

The rubber sector, already sensitive to tapping cycles, soil conditions and transport reliability, found itself squeezed from all sides. By October, large sections of Southeast Asia’s plantations were either facing rain or were waterlogged. On the other hand, the ASEAN Specialised Meteorological Centre warned of above-normal rainfall heading into early 2026, a projection that instantly filtered into price expectations, supply planning, and export behaviour.
 

SE Asia Weather outlook for December 2025 through February 2026

Source:: https://asmc.asean.org/asmc-seasonal-outlook/#

Thailand, the world’s largest producer, was severely hit by the recent rains. But disruptions did not follow borders; the same storm systems that inundated Songkhla washed into Malaysia’s northern territories, and the typhoons that lined Vietnam’s coast sent moisture cores drifting westward into Laos and Cambodia before dispersing into the Thai monsoon trough. The regional rubber market, typically segmented by country-specific dynamics, turned into a single weather-linked ecosystem where damage in one hub shifted buying patterns in another. In such a landscape, supply chain resilience became as important as production, and price movements began echoing rainfall maps as much as inventory data and Chinese demand.
 

Production Expectations Rewritten by Floods and Their Timings
 

Entering 2025, Thailand expected a modest rebound of nearly 3% from RAOT’s estimated 4.99 million ton production in 2024, when exports reached 3.86 million tons. Floods had reduced production in 2024 as well. Repeated flooding across September, October and November in 2025 forced experts to revise the projections for 2025. The Rubber Authority of Thailand in November 2025 reported that up to 90,000 tons may be lost from the year’s tally after 4.1 million rai (656,000 hectares) of plantations were inundated in November floods. More than 160,000 farmers were affected, particularly in the southern belt that accounts for more than half of the country’s total rubber area. Some analysts expect an overall 4-5% drop in Thai rubber production in 2025 while returns would be marginally higher than last year due to earnest production in early months when prices hovered high.
 

The weather imprint is not on Thailand alone. Industry sources estimated that both Indonesia and Malaysia would end the year with roughly 15% losses in Q4 output, while Vietnam—despite facing seven typhoons—managed a smaller 2% annual drop, though its Q4 contraction would be closer to 8%. The difference lies partly in timing: Vietnam’s majority storms arrived before its main tapping window, whereas Thailand and Indonesia faced heavy rainfall directly overlapping with peak production months. Malaysia, which had recorded an impressive 11% growth in output in 2024, found its gains unevenly carried into 2025 as Q4 rains disrupted tapping rounds and hampered transport.
 

The regional supply narrative revolved around when the weather struck. These divergences and the price factor help explain why Vietnam’s full-year value drop is expected to be only around 1.3%, whereas Malaysia and Indonesia face deeper declines of around 4.2% and 4.3%, respectively.
 

Prices Rise, Volumes Falter: A Market Driven by Contradiction
 

Throughout 2025, the market found itself suspended between price strength and volume weakness, a contradiction most visible in Thailand and Vietnam. Thailand recorded its highest monthly export earnings in eight years in February, reaching US$577.1 million, powered by higher STR20 prices well above the US$2,000/mt mark.  Yet only a month later, export earnings slipped to US$531.1 million as volumes fell by more than 200,000 tons even though prices remained high. The weak sentiment that aggravated with the tariff tightening compounded towards the end with weather playing spoilsport.
 

Vietnam showcased an even more pronounced price-led story. In 2024, it earned a record US$3.4 billion – up 18.2% YoY - despite a 6.2% volume decline—a dynamic that carried into early 2025. For the first nine months of 2025, its exports reached 1.3 million tons worth US$2.32 billion, flat in volume but up 10.8% in value. But by late Q3 and Q4, the typhoon season began eroding its pace, with industry reports signalling sharp slowdowns from October onwards.
 

Indonesia’s story unfolded differently. The country enjoyed a strong start, with January–May 2025 exports consistently above the 140,000-ton mark. But once the monsoon systems intensified, production volatility escalated. September’s level of 141,000 tons was followed by a plunge to just over 117,000 tons in October. Compared with 2024, when export volumes from August to December remained above 140,000 tons, barring a relatively marginal dip in November 2024, 2025 highlighted a structural vulnerability. The same weather patterns that pushed Thai production offline were simultaneously disrupting Indonesia’s production and logistics, driving down export realisations even when global prices were not that bad despite relatively weaker demand.
 

The market’s texture in 2025, therefore, became one where prices were relatively supportive but not a remedy amid not-so-supportive demand. As rains deepened and tapping days shrank, the price cushion could no longer shield exporters from the physical limits of supply and weaker demand. Moreover, occasional corrections in prices due to weak demand translated into sharp revenue dips.
 

Export Behaviour Mirrors Weather Maps
 

Nowhere was the weather-shadowed narrative more evident than in Thailand’s mid- to late-year export data. July exports climbed to 200,840 MT, up from 178,719 MT in June, but this volume increase coincided with a softening in value. By August, shipments inched up to 202,902 MT while revenue slipped to US$352 million from July’s US$364 million. The mismatch was emblematic of global rubber’s uneasy balance: buyers anticipated supply stress but hesitated to commit aggressively as broader economic indicators remained mixed.
 

Despite the growing impact of rainfall, September-to-October behaviour briefly defied expectations. Thailand’s shipments rose from just over 200,000 tons in September 2025 to more than 220,000 tons in October 2025, with earnings lifting from around US$373 million to above US$395 million. Chinese demand, which accounted for 30% of exports in September, surged to 40% in October—an early sign that buyers were beginning to front-load demand in anticipation of deeper Q4 shortages. But the year-on-year comparison was sobering: September 2024 saw over 228,000 tons exported with US$471 million in earnings, while October 2024 delivered over 224,000 tons and US$476 million. The contrast underscored how much the 2025 rains had cut into peak-season throughput, even before official November figures—likely to reflect the worst losses—were released.
 

Indonesia’s export rhythm also pivoted around its rainfall geography. Provinces such as North Sumatra and Kalimantan experienced flash floods in November, while flood levels impeded transport to processing facilities. As a result, export volumes increasingly reflected tapping disruptions and availability of transport over the preceding weeks rather than seasonal expectations. Malaysia exhibited similar traits: despite its strong 2024 performance, Q4 2025’s rains not only reduced yield but also caused delays in delivering rubber to factories and ports, leading to uneven monthly shipments.
 

Across the region, the export map evolved into an index of weather impact. Countries that caught shorter rain cycles managed better-than-expected volumes; those hit by prolonged monsoon pulses saw their throughput collapse.
 

A New Climate Regime and the Future of Rubber Supply
 

The 2025 season marks more than a difficult year—it reflects a structural shift in the climate risks surrounding Southeast Asia’s rubber base. The World Meteorological Organization reported that global temperatures last year were 1.55°C above pre-industrial levels, the highest ever recorded. Asia is warming at nearly twice the global average. This heightened baseline makes each La Niña, each negative IOD, and each typhoon season more potent than their historical equivalents.
 

La Niña is expected to persist into early 2026, raising the likelihood that the first quarter of the coming year will continue to face abnormal rainfall. With soils already waterlogged across parts of Thailand, Malaysia and Indonesia, even moderate rainfall could trigger fresh rounds of flooding or slope failures. Supply-chain uncertainty may therefore continue well beyond the current season, with implications for tapping schedules, transit times and export commitments amid labour shortage.
 

Governments and producers are beginning to acknowledge that the old climate cycle is not returning. Specialists argue for accelerated adaptation: stronger drainage networks, redesigned plantation layouts to improve water retention and runoff, coastal and riverbank fortification, and advanced early-warning systems for plantation-level decision-making. The rubber sector’s structural sensitivity—where a few lost tapping days can reshape monthly output—means the cost of inaction is rising rapidly.
 

The region’s 2025 experience shows that the rubber market is no longer simply responding to price cues or demand signals. It is, increasingly, negotiating with the climate. And unless the next cycle brings a reprieve, weather conditions will continue to exert influence on rubber markets like any economic or geopolitical factor in the near term.