Cold Comfort

Warlock Invocation
Level: Warlock Invocation, Lesser, 2nd lv.
Components: V, S
Casting Time: 1 standard action
Range: Self
Duration: 24 hours
Saving Throw: None
Spell Resistance: No

Your unnatural aura renders you partly immune to the ravages of the environment. You remain cool in hot weather and warm in cold weather, as the spell endure elements. Additionally, you radiate a small aura of warmth or cold; allies within 30 feet of you also benefit from this effect. This invocation lasts for 24 hours

(Complete mage, Page 123)