In lieu of only searching rip-stop which sometimes is kind of common I would look into
- “technical” / “performance” fabrics are often something you have to search for separately.
Stuff like:
gore-tex
DWR (durable water repellence)
Waterproof-breathable.
I say that because not all rip-stop is created equal. Usually the waterproof breathable raincoats you find from North Face, Patagonia, Arcteryx, etc. are bonded seams and have a multilayer construction which is much more durable (and opaque) than standard store-bought rain fabric.
As suggested you could also look into heavy waxed cotton
pleather
Light-weight neoprene
garment weight leather
I would NOT look into waterproof fabrics that are outdoor utility, furniture, or traditional vinyl. Wearing those would murder you.
another option: find some quality pre-made ponchos of the correct color and use them AS fabric
Edit:
HotSauceChrmn Grab yourself some .25 yds of Navy and Brown from here as samples
Supplex Nylon Fabric | Taslan Nylon | Seattle Fabrics
Also:
1.4 oz 10D Waterproof/Breathable
Note “Dark Olive” and the white backing on the roll;
These fabrics have ripstop but also have the laminated backing for wicking and preventing water penetration which helps maintain your “micro climate”. (Comfort and moisture level while wearing) I think that’s closer to what you’re wanting.
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