Washington, D.C., Maryland, and Virginia Sleet Storm Explained: Why Sunday’s Winter Storm Was Far More Destructive Than a Typical Snowstorm
WASHINGTON, D.C. — The winter storm that shut down the Washington, D.C. region on Sunday was not exceptional simply because of how much precipitation fell, but because of what fell and how cold it was when it fell. Data from snowfall and sleet accumulation reports show this storm behaved very differently from a standard Mid-Atlantic snowstorm — and that difference explains why impacts were so severe and long-lasting across the District, Maryland, and northern Virginia.
Historic Sleet at Unusually Low Temperatures
The defining feature of this storm was heavy sleet falling at temperatures mostly in the teens, an extremely rare combination for the region. Normally, sleet events occur near the freezing mark and in relatively small amounts, often less than an inch.
This storm, however, produced up to 4 inches of sleet, an amount that has not been observed in the D.C. area since at least February 1994, according to historical comparisons shown in the data.
Why This Storm Was Worse Than the Snow Totals Suggest
On top of the sleet layer, 4 to 7 inches of snow accumulated across much of the region. As the storm progressed, the snow compacted into the sleet beneath it, creating a dense, ice-laden mass measuring 6 to 9 inches deep.
Despite the modest depth compared to major blizzards, the water content of this accumulation was extreme — comparable to what would normally be found in a 20-inch snowfall. That density explains the widespread tree damage, power outages, and treacherous travel conditions.
Why Melting Will Take Much Longer
Nighttime temperatures are forecast to plunge into the single digits for several consecutive nights, with daytime highs struggling to rise above freezing. Because of this prolonged cold, the compacted sleet-snow layer is expected to remain frozen solid well into the week, delaying cleanup and recovery.
Unlike powdery snow, sleet does not melt easily — especially once it refreezes into a concrete-like slab.
A Rare Atmospheric Collision Created the Storm
Meteorological data shows the storm formed from a rare collision of extremes:
- A powerful Arctic air mass, originating from Siberia, surged southeastward into the Mid-Atlantic
- At the same time, a deep Pacific moisture plume — often referred to as the Pineapple Express — streamed in from near Hawaii
The National Weather Service summarized the setup as “the Pineapple Express meeting the Siberian Express.”
This clash created narrow temperature margins between snow, sleet, and freezing rain, making precise forecasting extremely difficult.
Why Forecasts Varied So Widely
Because the storm’s precipitation type depended on minor temperature differences of just 1–2 degrees, forecast models showed large variability. Some early projections advertised snowfall totals exceeding 20 inches, while others leaned toward lower numbers.
Despite that uncertainty, forecast guidance correctly identified the core threat more than 48 hours in advance:
A crippling sleet-heavy winter storm with high impact potential, not just a routine snow event.
Why This Storm Will Be Remembered
This was not a typical Mid-Atlantic winter storm. The data shows it was:
- Sleet-dominant, not snow-dominant
- Much colder than average for a sleet event
- Denser and more destructive than snowfall totals alone would suggest
- Slow to melt, extending impacts for days after the storm ended
These factors combined to make Sunday’s storm one of the most disruptive winter weather events the Washington, D.C. region has experienced in decades.
What do you think — was this storm worse than past D.C. snowstorms you’ve experienced? Share your thoughts and stay informed with ongoing weather analysis at WaldronNews.com.