[Routine Help] Studying abroad. Advice about shelf life/serum recs/climate effect on skin?

Hi everyone! In August I'll be leaving for Italy to study abroad for four months (currently, I live in the continental US in the midwest). I'm anticipating the much climate is going to be pretty big shock to my skin, which is sensitive but normal/borderline combo overall.

I was looking at a Vitamin C serum to replace my Acure/Nyx once they're gone, but I'm reading that the shelf life is 2-3 months, and they need to be refrigerated. I don't think that's going to be doable for me while abroad, unfortunately. I'll be there for 4 months, in any case.

Just looking for anyone who might have experience with the climate (I'll be in Florence, mostly), as well as any serum recommendations? I'd like to go with a gel or lightweight cream moisturizer and just skip on VitC until I'm back home.

Current routine
AM
S:um37 Miracle Rose Cleansing Stick (w/Clarisonic)
Pixi Glow Tonic (not seeing results, just trying to use it up)
Lush's Breath of Fresh Air Toner
Acure Seriously Glowing Facial Serum OR NYX Honey Dew Me Up (depending on weather and skin needs)
The Face Shop Mango Seed Silk Lotion
Derma e Vitamin C Renewing Moisturizer (I'm using it on eyes/as needed to even redness/tone)
Biore Aqua Watery Essence SPF 50+
as needed for hydration: Mario Badescu Rosewater Facial Spray

PM generic makeup wipes if I'm wearing eye makeup/mascara. I don't wear foundation or concealer unless I'm having a dark circle day
Simple Hydrating Cleansing Oil w/grapeseed
Acure Sensitive Facial Cleanser
Pixi Glow Tonic OR x1 weekly Pacifica Kale Juice Cleanse AHA Mask
Lush's Breath of Fresh Air Toner
Acure Seriously Glowing Serum
J. One Hana Cream (love it and I'm running out, but too expensive to quantify another purchase :( switching it out w/ Cerave PM)
Derma e Vitamin C Renewing Moisturizer
Lip exfoliation (currently Bite's Agave Sugar Scrub...again, love it, running out, too expensive to repurchase)

I've heard good things about Avalon Organics Intense Defense with Vitamin C. Can anyone attest?

Thanks for any help <3