Riddles from the Border Regions, 03/24/12

Arriving
Like King of the Jungle, I roar
Then sheepishly leave
After one half and four.

This is a riddle about the volatile weather in the month of March.  It's build around the familiar phrase, "In like a lion, out like a lamb."   What a lovely word-picture to describe the transition from the boldness of winter to the gentleness of spring.   But how about that tricky last line?   'It sheepishly leaves after one half and four.'  What's that talking about?   It's a round about way of expressing the number of weeks in March.

NEW RIDDLE:
I tally up the alphabet
A marathon also
Atomic iron, there am I
What am I, can you tell?