Seattle experiences its heaviest rainfall during the months of November, December and January, receiving roughly half of its annual rainfall (by volume) during this period. In late fall and early winter, atmospheric rivers (also known as "Pineapple Express" systems), strong frontal systems, and Pacific low pressure systems are common. Light rain & drizzle are the predominant forms of precipitation during the remainder of the year; for instance, on average, less than 1.6 in (41 mm) of rain falls in July and August combined when rain is rare. On occasion, Seattle experiences somewhat more significant weather events. One such event occurred on December 2–4, 2007, when sustained hurricane-force winds and widespread heavy rainfall associated with a strong Pineapple Express event occurred in the greater Puget Sound area and the western parts of Washington and Oregon. Precipitation totals exceeded 13.8 in (350 mm) in some areas with winds topping out at 209 km/h (130 mph) along coastal Oregon. It became the second wettest event in Seattle history when a little over 130 mm (5.1 in) of rain fell on Seattle in a 24-hour period. Lack of adaptation to the heavy rain contributed to five deaths and widespread flooding and damage.
What quantity of yearly rainfall does Seattle have during the winter?
half