🧊 Freezing Rain & Sleet

KMDT leads in FZRA hours (462h) — The Harrisburg International Airport reports significantly more freezing rain than the other three stations, likely due to its position near the Susquehanna River valley and its exposure to warm-air overrunning events. 2008 was the standout year with 46 hours.

KMDT dominates sleet (151h vs ≤3h at other stations) — This remarkable disparity suggests KMDT's position in the Susquehanna valley exposes it to temperature profiles favorable for sleet formation (above-freezing layer aloft, below-freezing near surface). KYORK has recorded zero sleet hours in the 25-year record.

2004 and 2008 were peak FZRA years — KYORK peaked in 2004 (35h), KMDT in 2008 (46h), and KLNS also in 2008 (33h). These years featured multiple ice storm events across the region, consistent with La Niña patterns that often increase freezing rain frequency in the mid-Atlantic.

KCXY (Capital City Airport) reports the fewest FZRA hours (251h) — Located just north of Harrisburg in a slightly elevated position, KCXY may experience more all-snow events that would otherwise be ice at lower elevations. Its sheltered position from the Susquehanna Valley drainage may also reduce freezing rain exposure.

2010, 2017, 2020, and 2023 were near-zero FZRA years — Despite being active snow seasons in some cases, these years had very little freezing rain. The 2009–10 season, despite producing 46" of snow at KMDT, had almost no freezing rain — consistent with the cold, dry powder storms that dominated that record winter.