Looping in a 3D matrix - desperate for assistance!

[killerrex]

You can use the max function from numpy, choosing the axis where you want to perform the operation:

# Create a dummy array of 5 x 3 x 3 where 1st dimension is time and the others are space position.
>>> import numpy as np
>>> q = np.array(range(5*3*3))
>>> q.shape = (5, 3, 3)
# Get the maximum for all the elements
>>> np.max(q)
44
# Get the max for each lat, lon
>>> np.max(q, axis=0)
array([[36, 37, 38],
       [39, 40, 41],
       [42, 43, 44]])
# Get the max for only the times 2 and 3:
>>> np.max(q[2:4, ...])
35

Try using array selection operations (slices, masks) and playing with the axis parameter to obtain the values you want.