Magic is nothing more than an act of the imagination fired by the senses, then given shape by the power of the Aura. The more powerful the Aura, the Greater the magic. Losing control of any magic results in Spontaneous Human Combustion (SHC), where the aura feeds on the user that leads to this situation.
Magic of Air
"There are those who will tell you that the magic of Fire or Water or even Earth is the most powerful magic of all. They are wrong. The Magic of Air surpasses all others. Air can extinguish fire. It can churn water to mist and can rip up the earth. But air can also bring fire to life, it can push a boat across still water, can shape the land. Air can clean a wound, can pluck a splinter from a fingertip. Air can kill."
Magic of Fire
"There are those who will say that the Magic of Air or Water or even Earth is the most powerful magic of all. They are wrong. The Magic of Fire surpasses all others. Fire consumes air. It can heat water to mist and can crack open the earth. Fire destroys, but it also creates. A forest needs fire to thrive. Certain seeds depend on it to germinate. In ages past, fire warmed the humani, allowed them to survive in harsh climates. This is the Magic of Fire. Cooking (with fire) made it easier for mankind to digest the meat they hunted, allowed them to absorb the nutrients more easily. It kept them warm and safe in their caves, harden their tools and weapons. Fire has driven every great civilization, from the ancient world right up to the present day. Without the heat of the sun, this planet would be nothing more than rock and ice.The Magic of Fire is strongest in sunlight. Without fire, we are nothing. Fire can heal; it can seal a wound, can cut out disease. It is unlike any other magic, because it is the only one directly linked to the purity and strength of your aura. Almost anyone can learn the basics of Earth, Air or Water magic. Spells and incantations can be memorized and written down in books, but the power to ignite fire comes fron within. The purer the aura, the stronger the fire."
Losing control of fire elements (when tired/weakened) will cause the fire to snap back at the user and burn the user to crisp in a heartbeat.
After learning Magic of Fire then coldness would not be experienced again. Controlling the Magic of Fire requires a trigger, until the user are having full control at Magic of Fire in full control, only then would be able to be control with their own will. Fire can be shaped.
SPOILER COMMENT ALERTED!!!
Magic doesn't need to be use even if not awakened... It seems that some of the immortal such as Nicholas Flamel himself doesn't possess the power of Heightened senses, hence he may be not be awakened. Instead, his Alchemist skill, should be part of magic, is just acquired from The Book of Abraham the Mage. This is being listed in the first book, The Alchemyst, where Nicholas himself admitted that he is unable to see the aura of other people. This is half half true, as we all knows that Nicholas lies half and the other half is absolutely true. The twins of legend, Sophie Newman and Josh Newmanare able to see each other's aura, as they did in Hekate's shadowrewlm when being touched by Hekate. This is unsure whether is because they are too strong as being the twin of legend or they are being awakened. This is also proven that when they are fighting at the Notre Dame Cathedral with Dee's force where they actually could mix their power to become the two that are one. This had proven that they are being Awakened and being able to see their senses. However, this is just a comment, and too, is a spoiler.
SPOILER ENDS HERE!