Supporting data for: A big chill: Examining an extremely sharp cold front from three perspectives

On 21–22 December 2022, an extremely strong cold front moved southward
through the High Plains of the United States. The frontal passage
was associated with rapid temperature decreases that rivaled or
exceeded the largest that have been reported in the literature. In
many locations in Wyoming and Colorado, the temperature dropped
from above freezing to below zero Fahrenheit (below –17.8°C) in a
few hours. High-resolution observations from an eddy
covariance tower in Akron, Colorado revealed a 2-m air
temperature drop of 13.8°C in 10 s and 15.4°C in 30 s, showing
that this front effectively represented a discontinuity in temperature.
Operational forecast models indicated the potential for a strong
cold front up to 9 days in advance, but displayed considerable
run-to-run variability and uncertainty in the timing of frontal passage.
Forecasts from data-driven weather prediction models (trained
using deep learning) were generally more accurate than those from
physics-based models in terms of the timing and location of the front, but
did not represent the extreme temperature gradients that
occurred. Short-term operational model forecasts provided a
detailed depiction of the front, but predicted the frontal passage to be
slightly slower and weaker than was observed. A high-resolution
numerical simulation reveals a frontal structure akin to a
density current with a hydraulic head, consistent with past observations
of intense cold fronts to the east of the Rocky Mountains. In
total, this study provides climatological context and a detailed
picture of forecast performance and physical processes for one of the
sharpest cold fronts in U.S. records.