Weather and Cricket: Duckworth-Lewis-Stern, Covered Pitches, and Rain Rules
How weather affects cricket — the history of uncovered versus covered pitches, the Duckworth-Lewis-Stern method for rain-interrupted limited-overs matches, and why modern weather forecasting has changed how teams prepare.
Cricket's long history has been inextricably linked with weather. As an outdoor sport played over days, Tests have always been vulnerable to rain, bad light, and damp conditions that fundamentally alter the playing surface. Before covered pitches became standard in Test cricket, the relationship between weather and pitch condition was even more profound: a rain shower followed by sunshine could transform a flat pitch into a 'sticky wicket' on which batting was nearly impossible, creating dramatic reversals of fortune that were both exciting and profoundly unfair. Today, covered pitches eliminate this specific hazard, but rain still interrupts play, and for limited-overs cricket the Duckworth-Lewis-Stern (DLS) method provides a mathematically grounded way to set revised targets.
Uncovered Pitches: The Original Weather Variable
For much of cricket's history, pitches were left exposed to the elements between innings and overnight. This created the phenomenon of the 'sticky wicket' or 'sticky dog' — a pitch that had been soaked by rain and was then dried rapidly by sun and wind, causing the surface to become tacky, variable in bounce, and extraordinarily difficult to bat on. A team batting on a sticky wicket against quality spin bowling could be bowled out for 30–50 runs even if they had scored 300 the previous day on a flat surface. Jim Laker's 19 wickets in a single Test (Old Trafford, 1956) benefited from a turning track, but many of cricket's most one-sided scorecards in the pre-1950 era reflected sticky dog conditions more than quality differences between the teams. The ICC introduced mandatory pitch covering at Test level, and England eventually adopted covered pitches in domestic County Cricket in the 1980s — a change that increased scores and produced the higher-average batters of the modern era.
Duckworth-Lewis-Stern: Fairness in Rain-Interrupted Matches
The DLS method — developed by statisticians Frank Duckworth and Tony Lewis and later updated by Steven Stern — is the ICC-approved formula for revising targets in limited-overs matches interrupted by rain or bad light. The key insight of DLS is that a batting team's 'resources' are a combination of overs remaining and wickets in hand, and both must be accounted for when calculating a fair revised target. Earlier systems, including the 'Average Run Rate' method (simply extrapolating the runs per over already scored), could produce absurd results: a team scoring 200 in 40 overs before rain stopped play with 10 overs remaining would 'need' to have scored 250 in 50 overs — even if they had already lost 9 wickets and had no resources left to accelerate. DLS replaced these systems by maintaining a resource table that weights each combination of overs and wickets differently, and the revised target reflects what the batting team 'would have been expected to score' with the resources they actually had available, compared to the resources the bowling team had available.
Frequently asked questions
How does the DLS method actually work in practice, and why do critics argue it sometimes produces unfair revised targets?
The Duckworth-Lewis-Stern method is considerably more mathematically sophisticated than it appears from a broadcast graphic showing a revised target number. Understanding how it works, and why it is sometimes controversial, requires following the logic of its core assumption. The method operates on the concept of 'resource percentage'. At any point in a limited-overs innings, a team has two resources: the number of overs remaining and the number of wickets remaining. A team with all 10 wickets and 50 overs has 100% of their resources. A team with 5 wickets lost and 10 overs remaining has a much smaller percentage of their resources. DLS uses a pre-calculated table (derived from statistical analysis of thousands of completed innings) that assigns a percentage value to every combination of overs remaining and wickets in hand. When rain interrupts play, the revised target is calculated by comparing the resources available to each team. If Team A bats 50 overs without interruption and scores 250, they used 100% of their resources. If rain then reduces Team B's innings to 40 overs before they start batting, they have approximately 90% of their resources (40 overs, 10 wickets). Team B's target is set at what Team A would have scored with only 90% of their resources — which might be around 225, not 250. Team B needs to score 226 to win. The situation that attracts most criticism is when rain interrupts an innings in progress. Suppose Team B is batting in 50 overs, is 35/0 after 10 overs, and rain halts play. When play resumes with 20 overs remaining, they have lost 20 overs from their innings but still have all 10 wickets. DLS calculates their revised target based on the resources they started with (50 overs, 10 wickets = 100%) minus the resources they lost (20 overs from an innings with 10 wickets = a large resource percentage), giving them a revised target that reflects a high run rate requirement. Critics argue that this penalises attacking batting teams who were on track for a fast score: Team B was scoring at 3.5 per over — below the rate needed to win — but DLS compresses their chasing opportunity and demands a faster rate for the shortened innings. The most extreme criticism often comes from T20 cricket, where the shorter format means each over lost represents a proportionally larger resource loss, and revised targets for very short matches (5–10 overs per side) can seem arbitrary. A T20 revised to 6 overs and requiring 72 to win (12 per over) when the original target was 160 from 20 (8 per over) represents a genuine shift in difficulty that DLS computes as equivalent but that batters and fans do not always accept as fair. The ICC periodically reviews the method, and Steven Stern's 2014 update improved it for high-scoring T20 matches, but it remains an imperfect approximation of an inherently unquantifiable question: 'what would have happened if it hadn't rained?'