General

Finding the sites

Winter Nexus combat sites spawn in systems affected by volatile ice storms in HS, LS and NS.
LS sites are assumed to be the most valuable ones, followed by NS and then HS.

Access and difficulty

HS sites disallow Marauders unless a Cryostorm Clarifier (from Yoiul LADs) has been deposited into Sansha's Transit Modulator, upgrading the site (increased difficulty & better loot)

LS sites can be upgraded with a Cryostorm Reconciler

NS sites can be upgraded with a Cryostorm Mapper