The short answer is "Yes" but I would not recommend it. Occasionally, this will come up for a variety of reasons. Maybe you have a vacation planned or there is a family emergency or last minute business trip that you cannot miss. Whatever the reason, it happens, and you should know what your options are.

Option 1- Power of Attorney

A power of Attorney (POA) by definition is a written authorization to represent or act on another's behalf in private affairs, business, or some other legal matter. On a real estate transaction such as a purchase loan or refinance loan you would need to get a "Specific Power of Attorney" which is specific for that transaction only. Therefore, whoever you elect to act as your power of attorney can only sign on your behalf for that specific transaction at hand. A specific power of attorney document can usually be drafted by your local escrow or title officer. Please note to consult with your lender to confirm that this option is available, some circumstances could prevent the use of a POA.

Option 2- Sign your final loan docs at a US Embassy or US Consulate

If the city you will be visiting is a major city it might have a US Embassy or Consulate. Check the cities here. http://www.usembassy.gov/ If the city you will be visiting does have a US embassy or consulate then you can make an appointment to have your documents notarized by a notary public. Again you must check with your lender to see if they will allow you to sign your final loan documents internationally.

I can't stress enough that you must check with your lender, realtor, and escrow/closing attorney to verify that these options are allowable and feasible for your situation.