The Knickerbocker Storm
The Knickerbocker Storm dumped the heaviest snowfall ever recorded in Washington DC history and registered as a Cat 4 for the Southeast Region and a Cat 2 in the Northeast Region. The snow began at 4 pm, on the 27th and 16 hours later at 8 am on the 28th, 18 inches of snow had fallen. By 2 pm, 25 inches of snow had fallen and it had only been 22 hours since the first flakes fell. Heavy snow continued to fall through the day and ended just before midnight. At around 9 pm, the roof of the Knickerbocker Theater collapsed under the weight of the snow crushing and killing around 100 of the 300 movie goers. Snow totals from this storm in the D.C. area ranged from around 24 to a staggering 38 inches. This storm brought snow from South Carolina all the way to southern Massachusetts. (Kocin and Uccellini)
The storm by region
Each region’s thresholds are its own, so the same depth of snow counts for more in the South than in the Northeast.
| Region | Index | Category | Area with snow (sq mi) | People under snow | Above the top threshold (sq mi) | People above it |
|---|---|---|---|---|---|---|
| Southeast | 18.53 | Category 5, Extreme | 150,041 | 30,065,300 | 19,566 | 4,661,160 |
| Northeast | 3.76 | Category 2, Significant | 102,682 | 53,135,150 | 0 | 0 |
| Ohio Valley | 0.27 | Below category 1 | 163,437 | 17,796,724 | 0 | 0 |
| South | 0.23 | Below category 1 | 109,275 | 7,707,957 | 0 | 0 |
The Regional Snowfall Index is NOAA’s ranking of snowstorms east of the Rockies by how much snow fell, over how wide an area and on how many people, region by region: the area and the population above four snowfall thresholds set for each region, weighted against that region’s own history. A storm is scored in each region it reached, on a scale from 1, notable, to 5, extreme.
In the Storm Events record
The Storm Events Database holds winter weather only from 1996, so this storm has no episodes there.
More
The snowstorm of November 7 to 10, 1921The snowstorm of December 12 to 16, 1922Snow nowEvery winter storm filed
Sources
NOAA NCEI Regional Snowfall Index, and the Storm Events Database for the episodes.