Is It Raining in Seattle?

You're preparing for a trip to Seattle and want to decide if an umbrella is necessary. To find out if it's raining, you contact three friends living there. Each friend has a 2/3 probability of giving you truthful information and a 1/3 probability of jokingly lying. All three friends confirm, "Yes," it's raining. Calculate the probability that it is indeed raining in Seattle.