Rainfall

Rainfall measurement isolates liquid precipitation from snow and ice, tracking pure water delivery in millimeters to forecast stream volumes, waterfall flows, puddle formations, and moisture-enhanced landscapes for photography. While total precipitation aggregates all forms, rainfall specifically indicates liquid water immediately available to saturate ground, fill streams, and create the wet surfaces that enhance color and texture in photography.

For waterfall photographers, rainfall totals directly predict flow rates: 5-10mm produces noticeable increases, 15-30mm creates impressive volumes perfect for silky-smooth long exposures, and 50mm+ generates powerful flood-stage flows requiring wide-angle compositions to capture full drama. Timing matters: waterfall flows peak 6-12 hours after rainfall ends as water drains from watersheds, creating a predictable window for planning shoots. Rainfall also saturates ground and vegetation, intensifying colors by darkening surfaces and eliminating dusty coatings: greens become vivid, rocks turn deep slate, and bark displays rich brown tones impossible in dry conditions.

Light rainfall of 0.5-2mm creates atmospheric effects without overwhelming equipment protection: misty air, beaded water on vegetation, and the authentic rainy-day mood urban photographers seek. Moderate rainfall of 3-8mm challenges weather sealing but produces dramatic storm scene opportunities for prepared photographers. Heavy rainfall above 10mm/hour forces most photography to cease but creates spectacular clearing conditions 2-4 hours after passage. Rainfall accumulation forecasts next-day fog formation: 10-20mm saturating landscapes combined with overnight clearing and light winds virtually guarantees morning ground fog in valleys and low areas. Multi-day rainfall totals above 50mm transform landscapes, swelling every stream, filling seasonal waterfalls, and creating temporary reflection pools in normally dry depressions. PhotoWeather tracks rainfall accumulation and timing to alert photographers to waterfall flow enhancement windows, predict post-rain fog formation overnight, forecast wet-surface color enhancement opportunities, and time arrivals for clearing storm edges where lingering rain columns catch dramatic light. Understanding rainfall patterns helps photographers distinguish between widespread stratiform rain lasting hours with gradual onset and ending, versus convective showers with intense bursts separated by dry intervals offering shoot windows between cells.