February may be the month of hearts and flowers, but it's also prime time for financial cons, from imposter fraud to the "sweetheart scam." The reasons for the seasonal lift in these scams are simple enough. Many people, still keeping with their New Year's resolutions, are looking for love and are especially vulnerable to scammers. Others are stuck at home during the winter months and are more likely to answer calls from financial fraudsters. Older Americans are especially at risk. Indeed, those over 65 are 34 percent more likely to have lost money on a financial scam than people in their 40s, according to research by the Stanford Center on Longevity and the Financial Industry Regulatory Authority's Investor Education Foundation. And almost 1 in 20 elderly respondents in a large 2014 study of New York residents reported being financially exploited at some point in their later lifetime. In addition, one estimate says only 1 in 44 financial fraud victims report what has happened, often out of embarrassment or fear that their children will want to take control of their finances.

"This is such an underreported crime," said Amy Nofziger of the AARP Fraud Watch Network.

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Right now, one of the scams on the rise is the so-called sweetheart scam. Like younger folks, older Americans are increasingly using online dating sites, and those sites can open a window for scammers. These scammers find an older woman on a dating site and establish a bond. Often, they persuade the victim to take the conversation off the site, thereby eluding any safeguards the dating site offers. Soon, the scammer proclaims "love" and then explains a predicament they say they are in: They have lost their passport and can't get home unless someone can give the embassy money to process their new one, or they're on a business trip and their briefcase was stolen, or something similar.

Many single people make new year's resolutions to find a partner, Nofziger said, and around Valentine's Day, "people are feeling vulnerable. They want to be in a relationship. They want to feel love. So they go online." She said she recently got a call from a woman who was swindled out of $180,000 in a sweetheart scam.

Another scam trending right now is the impostor scam. In these scams, fraudsters call or email and say they are from an agency like the IRS. They tell the target they owe back taxes and provide an address for them to send money. Janey Peterson, an associate professor of clinical epidemiology at Weill Cornell Medical College and lead author of the New York financial fraud study, said her mother has been a target of financial scammers multiple times in the past year. "This whole phone scam thing, to me, has hit this fever pitch," she said. "I'm having a lot of trouble keeping my own family members safe." The grandparent scam is also prevalent these days. In this kind of scam, a fraudster calls and says "it's your favorite grandchild" or something of the kind. Then they say they are in a predicament—they're in jail, their wallet was stolen, or something similar—and they don't want their parents to know. They just want the grandparent to wire money. "We've asked victims, and they say, 'I'm a smart person. I should have known. But the minute they said they were my grandchild and I'm the only one that can help them, all my common sense went out the window,'" Nofziger said. Read MoreLook who's defrauding your mom and dad——

Women are more likely than men to become fraud victims, partly because they live longer and partly because older women today may not have the financial knowledge to easily spot a scammer. The typical victim of elder financial fraud is a white woman ages 70 to 89, according to a study by MetLife. She is likely to be lonely or isolated and suffer from some cognitive impairment.

But both men and women are currently vulnerable to a seasonal foe: The cold and snow in the Northeast is keeping elderly people indoors and thus more likely to receive fraudulent calls or online scams. "You are not out and about because you are afraid you are going to fall on the ice," said Alexandra Armstrong, a financial planner based in Washington. "This is a ripe time for scams because people are at home."

Some organizations are taking steps to curb financial fraud. AARP, for example, has its Fraud Watch Network, which provides a monthly alert about currently prevalent scams. It also offers an interactive map, so users can click on a state and find out which frauds are trending there. The Investor Protection Trust, an organization providing investor education, is providing medical professionals with guidelines on how to spot financial fraud and abuse as part of a program called the Elder Investment Fraud and Financial Exploitation Prevention Program. It is also working with the American Bar Association to develop a continuing legal education program on financial fraud and the elderly. In addition, the Consumer Financial Protection Bureau offers information and other resources designed to help seniors and others identify and guard against financial fraud.

Read MorePrivacy doesn't trump financial abuse of elderly