Historical weather data, all-time temperature records, and monthly climate averages for Lynden, WA. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5 in Lynden lands right around coin-flip territory for rain — there's a 52% chance of precipitation today, so don't leave the umbrella at home. Highs typically reach 56° with lows around 37°, though this date has seen everything from a balmy 73° back in 1906 to a brutal 21° in 1911.
Lynden's weather has real range — this corner of northwest Washington hit a staggering 106° on June 28, 2021, during the historic Pacific Northwest heat dome, and bottomed out at -4° on January 13, 1911. The wettest single day on record dumped 7.77 inches in January 1935, a reminder that this region's rainfall can go from steady drizzle to serious deluge.
Summers are the sweet spot — highs average 76-77° in mid-July and stay warm through August, making July 16–22 the warmest stretch of the year. Winters are mild but grey, with January highs only reaching the low 40s and November bringing the heaviest rains, averaging 1.59 inches in a single week. If you're planning a visit, June through September offers the most comfortable and driest conditions.