When the forecast is for warmish weather with wind and uncertain precipitation, you need something like the Arc'teryx
Squamish Jacket in your quiver. This super lightweight, extremely packable ripstop windshell provides just enough wind and water resistance and takes up so little space you can always bring it along.
Luminara™ (100% Nylon) - 20D mechanical stretch nylon ripstop with an air permeable PU coating and a DWR (Durable Water Repellent) face finish. A super light and breathable stretch fabric with great water repellency and wind resistance.
Athletic Fit - Arc'teryx's "Standard" fit, these complex patterns utilize anatomical shaping and gussets to enhance motion and eliminate excess bulk.
One zippered chest pocket that stows jacket
#3 Vislon front zipper with wind flap
Articulated elbows and gusseted underarms
Arc'teryx products can only be shipped within the U.S.