(Click read more to watch video of the rain and where the Obamas are expected to stay)

It's not just congressional action that is likely to put a damper on the first family's Christmas vacation - bad weather in Hawaii may also get President Obama's vacation off to a less than ideal start.

Snow flurries and flash floods aren't exactly the words you want to hear when you're going to a tropical destination, but that's just what the National Weather Service is saying about the Hawaiian islands Monday.

There's a flash flood warning for Oahu, where the president is expected to stay, and a flood watch for all the other islands.

The NWS predicts heavy rain and thunderstorms for Hawaii, and even moderate snowfall of up to five inches on the islands of Mauna Loa and Mauna Kea. The first family probably won't spot the snow, and at least the temperature is expected to be in the upper 70s, a heck of a lot better than the low of 23 degrees in Washington DC Monday, or the wintry snowy mix expected in the president's other hometown of Chicago.

Forecasters are calling this a rare and complex weather system.

First lady Michelle Obama, and daughters Sasha and Malia are already in Hawaii, and the president is expecting to join them mid-week.

The president would have already arrived by now, but was delayed with the action on Capitol Hill - and vowed to stay as long as lawmakers were working. Congress has been tackling a whole host of issues important to this administration, including repealing "don't ask, don't tell," a nuclear arms treaty with Russia (also called START), and how to fund the government and for how long.

Hawaii is also the boyhood home of the president, and he has spend the last two Christmases here celebrating with friends and family.

Last year the president was also late to his vacation because of the health care debate. And then the attempted Christmas-day bombing also interrupted some of relaxation time.

The same weather system is also drenching the west coast, and obstructing the view of the lunar eclipse, which will happen early Tuesday morning overnight. Locals are also concerned about the Hawaii Bowl, which is slated for Friday afternoon.

Fox News Photographer Eric Conner shot video of the rainy conditions and the neighborhood where the Obamas are expected to stay: