These companies let you hedge weather risk, refunding you the cost of your trip if it rains or gets too hot.

I’m a big fan of shoulder season; there are fewer people around and prices tend to be lower. I don’t want to go to European capitals in the summer when I’ll see more American teenagers than Europeans, who are on holiday themselves. At the same time, peak season is often peak for a reason—great weather matters. That’s why I book ski trips for February instead of April or December.

But what if you’re planning a once-in-a-lifetime trip that is expensive? What do you do if you run into bad weather? The whole trip might be “ruined” or at least not what you expected.

Companies have hedged weather risk for decades. Now it’s also possible for vacationers to do it, too.

  1. Weather Promise

Weather Promise offers a “weather guarantee,” refunding the cost of your vacation if it rains. They process refunds automatically based on the weather at your destination in 48 hours or less. And they offer coverage for “every location in the world.”

Here’s how it works: You book a trip with one of the company’s travel partners, buy a WeatherPromise based on trip destination and duration, and get a refund if the weather exceeds your guarantee. Each WeatherPromise is calculated on various trip parameters, including destination, start and end date, and the cost of the trip. It’s essentially a variation on the concept of travel insurance, but it has nothing to do with delays, missed flights, or lost bags. It’s all about protecting yourself if you hit lousy weather during your travels.

WeatherPromise counts a day of rain if it rains for at least three hours between 8 AM and 8 PM. They measure an hour of rain if it rains more than 0.06 inches (a light drizzle).

Here are some examples:

-to protect a $2,000 trip to Venice, Italy from June 28-30 costs just $150; Weather Promises would refund the entire cost of the trip if it rains just one hour between 8:00 AM. and 8:00 PM

-on a two-week trip to Thailand in mid-July, where you intend to spend $10,000 (which is the highest limit for coverage of any trip), you’d get a full refund if it rained at least five days on the 15-day trip, and you’d pay $500.10 for such coverage.

-protecting a five-day, $5000 trip to Ireland during December, the rainiest month, costs just $431.25.

Every WeatherPromise guarantee is backed by Greenlight RE, a global insurance company publicly listed on NASDAQ.

  1. Sensible Weather

Sensible Weather, a Los Angeles-based start-up, also provides weather guarantees for vacations and outdoor experiences. Recently, it has added high heat protection to its coverage. When booking through a Sensible partner, travelers will be able to add daily protection and if the temperature exceeds a threshold — usually set between 90 and 100 degrees — they can claim reimbursement. Currently, the insurance is only available in the United States, but, the company said, will gradually be rolled out in Europe and elsewhere.

“The goal of the company is to cover everything that can ruin a trip, and usually it’s rain, but temperature is number two,” said Nick Cavanaugh, the company’s founder who was developing the product while caught in a heat wave in Barcelona last year.

Customers do not need to cancel their trip in order to be reimbursed. Those on package tours are reimbursed for the average daily rate of their entire trip for each day that surpassed the heat threshold. So while you’re on vacation, if it’s too hot for some hours of the day and unpleasant to go outside, you can hang out in your air-conditioned hotel room and the company will still reimburse you.

Twist’s Take: If you’re worried about being rained out on your vacation, weather insurance may give you peace of mind. But even if you buy coverage, I would still bring an umbrella/parasol!