The alarm was shrieking. The front door was open. The family was away. The police car lights flashed and winked through the window.

An intruder had invaded while the family was on vacation. And the system was doing its job to foil the burglar. All was right, except the burglar was … me.

The family had left a small suitcase behind when I took them to the airport. I had gone back to retrieve it and would send it along. They gave me the key. But not the code to turn off their alarm.

Suitcases. Codes. Well, you can't remember everything.

Every summer, half the U.S. population takes a vacation. According to FBI statistics, most communities will experience a 10 to 18 percent increase in home burglaries in July and August.

Nine out of 10 home break-ins could be prevented if homeowners would do some planning and take steps to burglar-proof their homes, according to the Insurance Information Institute. So before leaving for the airport, make sure your home is safe.

No vacancy signs

One of the most effective ways to keep criminals away is to keep your house looking like you're home.

• Keep a car in your driveway or parking spot. If you're taking your car, ask your neighbors to park in front of your house.

• Leave blinds and drapes in their usual position, but make sure nothing valuable can be seen through the windows.

• Set light timers to come on at the normal after-work time. For a new twist on this tactic, there's FakeTV, a small electronic device that simulates real television lighting. Models start at $24.95 (www.faketv.com).

• Find a neighbor kid you can pay to come by and mow your lawn.

• Don't let mail and newspapers pile up outside your door. Again, you can rely on the kindness of friends, or you can ask your post office (holdmail.usps.com) and the newspaper (www.startribune.com/subscription­services) to suspend delivery.

Lock-down details

Good deadbolt locks are the hardest for burglars to breach. Go through each room and check that all windows, doors and sliding doors have their locks engaged.

Also remember:

• Two home entrances most commonly overlooked are the door to the attached garage, and any pet door. Double-check that both are locked.

• Unplug the power to your garage door to keep thieves from opening it with a universal remote.

• If you have an alarm system, remember to engage it. Obvious. But inform the alarm company in advance of the dates you will be away.

• Contact your police department to let them know you'll be on vacation — many will provide extra patrol in your neighborhood while you're out of town. Some even have vacation-check programs in which they actually inspect your property for signs of burglary.

Don't broadcast

Of course you're excited about your trip — unfortunately, others might be, too. Consider the ways you might inadvertently be sending your information into the wrong hands:

• It's not necessary to change your answering machine's outgoing message — you can easily play back messages and respond to anything urgent. If you must revise your recorded message, don't include any mention about being on vacation.

• Tell only those who need to know, and those friends and relatives you trust, that you're going away.

• Thieves prowl airport parking lots for cars and valuables to steal. Anything with your name and address on it could be pay dirt for a thief. Clean out anything with even a hint of your personal information, including mail, publications and receipts. Don't leave your GPS device, either, unless you want to leave a set of directions back to your house.

• There is anecdotal evidence suggesting social media sites have become a popular hunting ground for would-be burglars. Be careful what you post and tweet. Telling people you're on your way to the airport, uploading vacation photos to Instagram and similar forms of real-time communication can be a green light to the astute burglar. If you can't refrain from sharing while vacationing, check your privacy settings.

Think twice before you check in on a social network. Foursquare and review sites can let anyone view your whereabouts.

In the end, e-mailing, texting and even Skype are the best way to share your vacation in real time.

High-tech help

You can have your whole home in the palm of your hand, through the magic of apps. Automation today goes way beyond the average motion detector lights (though installing one or more is still a good way to deter burglars). Here are a few of the many home-monitoring and security systems available:

Ring Video Doorbell (www.ring.com, $199) and SkyBell Wi-Fi Video Doorbell (www.skybell.com, $199) both use a camera equipped with night vision, plus a monitor and speaker to show you, via smartphone, who's at the door. Both can be installed on your door, connecting into the doorbell. The doorbell's ringing triggers an alert to the app. You will be able to ask "Who's there?" through the bell's speaker; a burglar will think you're home, and move on. Both systems can detect someone stalking around the front of the house without actually pushing the bell.

Alarm.com (free) hooks up with your existing home security system, such as ADT or Guardian, to alert you in real time if there's any movement or security breach. It also enables you to access the home security video stream or change security settings remotely.

Canary ($249, www.canary.is) monitors your home via an HD camera with night vision, a microphone, motion sensors and climate sensor — comprehensive, though some reports cite an overly sensitive motion detector. Similar: Piper ($199, www.getpiper.com), Nest (starting at $199, www.nest.com) and Vivint (various packages available, www.vivint.com).

iSentry (free download) turns the webcam on your home computer into a surveillance system — although it will only monitor the area in which the cam is pointed. When motion is detected, the app notifies you on your phone. Similar: AtHome (free download); iCam ($4.99 download).