I do not know of any Blizzard rules in the User.pdf. I do have severe weather for when the blizzard hit at the Battle of Eylau.
Are you confusing this with the STORMS rules in the Panzer Campaigns series?
Here are the values for one of the turns during the Battle of Eylau (Scenario #056)
Blizzard (100% at 10:20 02/08/1807) Visibility: 2 Move Cost: 150%
Artillery Mod: 50% Fire Mod: 0% Attack Mod: -50% Flags: No Charges
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Generalfeldmarschall Wilhelm Prinz Peters von Dennewitz
3. Husaren-Regiment, Reserve-Kavallerie, Preußischen Armee-Korps
Honarary CO of Garde-Ulanen Regiment, Garde-Grenadier Kavallerie
NWC Founding Member
For Club Games: I prefer the Single Phase mode of play. I prefer to play with the following options
OFF:
MDF, VP4LC, NRO, MTD, CMR, PR, MIM, NDM, OMR (ver 4.07)