Yes

you do need a jacket based on the weather in Lynden, WA 98264, USA 22 minutes ago

Why? Because just cool enough for a jacket, but not warm enough to ditch it!
58°F15°C & Clear

Wind is 2 mph3 km/h from the Southeast, gusting to 6 mph9 km/h
August 2
6am58°F14°C2 mph3 km/h EastClear
7am57°F14°C2 mph4 km/h WestClear
8am57°F14°C4 mph6 km/h SouthwestClear
9am56°F14°C4 mph6 km/h SouthwestClear
10am59°F15°C2 mph3 km/h SouthwestClear
11am63°F17°C5 mph7 km/h SouthClear
12pm66°F19°C7 mph11 km/h SouthwestMostly Clear
1pm68°F20°C7 mph12 km/h SouthwestMostly Clear
2pm71°F21°C8 mph13 km/h SouthwestClear
3pm72°F22°C8 mph13 km/h SouthwestClear
4pm74°F23°C8 mph13 km/h SouthwestClear
5pm75°F24°C9 mph14 km/h SouthwestClear
DateLowHighWindDayNight
August 256°F13°C76°F24°C7 mph12 km/h from SouthwestClearMostly Clear
August 354°F12°C72°F22°C6 mph10 km/h from SouthwestPartly CloudyPartly Cloudy
August 454°F12°C72°F22°C6 mph10 km/h from SouthwestMostly CloudyCloudy
August 556°F13°C73°F23°C3 mph4 km/h from WestMostly CloudyDrizzle
August 659°F15°C73°F23°C4 mph6 km/h from SouthwestDrizzleDrizzle
August 756°F14°C74°F23°C4 mph7 km/h from SouthwestPartly CloudyMostly Clear
August 855°F13°C77°F25°C4 mph6 km/h from WestMostly ClearMostly Clear

Yes

Low of 55°F13°C, High of 72°F22°C
Wind: 6 mph10 km/h
Precipitation: None

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