Bowcast

Rainbow forecast for Victoria Falls

Victoria Falls, Livingstone, Zambia / Zimbabwe: today's peak estimated rainbow chance, the best forecast interval to look up, and the week ahead.

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Checking about 40 forecast ensemble members for sunlit rain near Victoria Falls…

Open the live map for Victoria Falls

Rainbow weather in Victoria Falls

Victoria Falls has a shortcut the rest of the world lacks: the falls make their own rain. On any sunny day, spray rainbows obey the sun rather than the weather, appearing whenever the geometry lines up: sun behind you, mist in front, sun lower than 42 degrees. Weather-made bows happen here too, on shower days.

At 17.9° south, Victoria Falls's midday sun often climbs above the geometry for a visible primary bow. Early morning and late afternoon are the most dependable viewing windows through much of the year.

Wherever you are, the geometry is the same: a primary rainbow forms opposite the sun while the sun is less than about 42 degrees above the horizon. Bowcast's research-informed heuristics give extra weight to clearing showers. The gauge above applies them to ensemble forecasts for the 12 km around Victoria Falls.

Rainbow questions, answered

When do rainbows appear in Victoria Falls?
Rainbows need sunlit rain with the sun lower than about 42 degrees, so in Victoria Falls useful windows often occur after sunrise or before sunset on showery days. A study in ZhaoSu, China found that about nine in ten observed rainbows occurred during the hour after rainfall. Bowcast uses that regional finding as research guidance, not a universal rate.
Where should I look for a rainbow in Victoria Falls?
Always directly opposite the sun: put the sun at your back and look toward the retreating rain. In the evening that means looking east; in the morning, west.
What is the estimated rainbow chance in Victoria Falls today?
Bowcast checks about 40 forecast ensemble members for sunlit-rain ingredients around Victoria Falls, hour by hour, for the next 7 days. The result is an estimated chance from model agreement, not a probability calibrated against observed rainbow frequencies. This page shows today's peak and best forecast interval; the Now board shows the interval containing the current time.

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