Can active duty who PCS overseas deduct Non-temporary storage (U-haul storage) for household goods left in the United States?

Yes.  According to the instructions for form 3903 (extracted below) the unreimbursed cost for storing household goods while stationed overseas is a deductible moving expense.  Use the "Moving Expenses" topic in the "Other deductions..." dropdown in the  "Deductions & Credits" Section. 

"Foreign Moves

A foreign move is a move from the United States or its territories to a foreign country or from one foreign country to another foreign country. A move from a foreign country to the United States or its territories isn't a foreign move. For purposes of determining whether a move is a foreign move, a U.S. military base is not a territory of the United States and moving to a U.S. military base located in a foreign country is a foreign move. For a foreign move, the deductible moving expenses described earlier are expanded to include the reasonable expenses of the following.

• Moving your household goods and personal effects to and from storage.
• Storing these items for part or all of the time the new job location remains your main job location. 
• The new job location must be outside the United States."