OğuzhanKöse

Rain Has Favorites

The average person in the US spent a month of the past year under a big rainstorm. Las Vegas: 4 days. Pittsburgh: 47.

3 November 2026 · Day 3: Polygons

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Hand-lettered title "Rain Has Favorites" in black ink above a watercolor map of the contiguous United States on textured paper. Overlapping blue washes show how many days each place spent under a big rainstorm between 1 November 2025 and 31 October 2026, from pale (1 or more days) to dark blue (60 or more). The East, from the Gulf Coast to the Ohio valley and the Appalachians, is darkest; the western Cascades reach 60 or more days; coral patches in Wyoming, Nevada and west Texas had none. Sixteen city labels give the counts, from New Orleans at 49 and Pittsburgh at 47 to Las Vegas at 4. A hand-drawn line chart below shows the 7-day mean of people under a big rainstorm, with a single-day peak of 135 million on 25 January 2026.
Days under a big rainstorm, 1 November 2025 to 31 October 2026. Full resolution

Each day’s big rain areas from NOAA radar became polygons, and each day’s polygons went onto the paper as one thin watercolor wash. The washes stack up for a year, from November 2025 to October 2026, so the places that kept getting rain are the darkest: the western Cascades, the Gulf Coast, the Ohio valley and the Appalachians. Parts of Wyoming, Nevada and west Texas had none. On 25 January 2026, 135 million people were under one at the same time.

The year, day by day.

Making it

Germany

The same hand-lettered title above a watercolor map of Germany, with a vertical legend on the left. Blue washes show days under a big rainstorm (10 mm or more over at least 1,000 km²) from pale (1 or more days) to deep navy (30 or more). The darkest band runs along the northern Alps in southern Bavaria, with dark patches in the Black Forest and around Cologne; the palest areas lie in Brandenburg around Berlin. Twelve city labels give the counts, from Cologne at 21 to Berlin at 4. Below, a line chart of people under a big rainstorm, with a peak of 46 million on 24 October 2026.
Germany, 1 November 2025 to 31 October 2026. Full resolution

The same method on DWD’s RADOLAN radar. Germany is much smaller, so a big rainstorm there needs only 1,000 km²; that size matched DWD’s station-based HYRAS grid best. The average person in Germany spent 13 days under one. The northern edge of the Alps had 30 or more, Brandenburg around Berlin 4 or fewer. The minimum areas differ, so the two maps can’t be compared number for number.

The 30 x 45 cm poster edition of the US map.The 30 x 45 cm poster edition of the Germany map.
Poster editions, 30 x 45 cm.

Data and method

NOAA MRMS MultiSensor QPE 24-hour totals (Pass 2), aggregated to 2 km. Each day was smoothed, thresholded at 10 mm, gaps closed by 25 km, and areas under 10,000 km² dropped. People are counted from 2020 Census tract centers of population; the average is the population-weighted mean (30.6 days; the median is 34). City counts were checked against PRISM. Germany: DWD RADOLAN SF, 1,000 km² minimum, Zensus 2022 1 km population grid, checked against HYRAS.

Sources

Questions, something to add, or a thought you’d like to talk through? Write to me, I’d love to hear it.