You didn't mention how or where the water is coming in at. Is it a trickle at the base of the wall? Is there a wet spot on the wall somewhere with the water sort of bleeding through? Do you have any wet spots up near grade level on the block that are shaped like an upside down christmas tree? That would indicate too high a grade at that spot causing the water to wick through the block. Main points to consider: if water is allowed to sit against the foundation, it will eventually find a way in. Water has to be directed away from the house. So if your downspouts aren't hooked into anything and just spill out a foot from the house, that water will saturate the ground and cause problems, especially this time of the year.
Also, as far as waterproofing, pull back a little dirt and see if you see the foundation coating. It should be higher than the grade. A lot of the time, people build up flowerbeds with mulch against the house and cause problems. Let us know what you find.