NAKHON SI THAMMARAT: Rain was pouring down as darkness descended last night and the torrents are still tumbling today. The drowning of Phuket's surrounding southern provinces is Thailand's first disaster for 2012.

We set out to see what how badly the high-season floods are affecting Phuket's neighbors this holiday long weekend, and we found the answer quickly.

Within the first hour of driving off Phuket, we'd come across five crashed vehicles beside the road. In the worst case, emergency workers were struggling to remove a sedan that had plunged into a creek bed.

Every other case, including a minibus that could have contained passengers at the time it crashed, was a wreck by the roadside or on the median strip.

But the real shock was the water. A long tailback in Krabi Town, where deep floods across the main thoroughfare outside Big C and Tesco-Lotus required a diversion, did not prepare us for Nakhon Si Thammarat.

The province appears to be sinking.

We criss-crossed back roads that have, from experience in past floods, been raised as high as possible. For kilometre afer kilometre, we passed houses half-sunk.

As night fell, their mirrored images reflected in the glint and glimmer of what seemed to be a huge inland sea.

If the weather remains reasonable in Phuket, and the holiday destination seems as charmed so far in 2012 as it was in 2011, the floods are still likely to isolated the island from near-neighbors.

And the forecast is for more and more rain.

Phuketwan reporters were on the spot in March last year when flash floods brought 10 deaths and crushed village houses in Krabi. Our perception, based on what we've seen so far around Phuket's neighboring provinces this year, is that the worst may be yet to come.

We're told the rising water now threatening houses across huge tracts of Nakhon is also a threat to thousands of homes in low-lying areas across virtually all of Phuket's neighboring provinces.

In the surrounding hillsides, it has the prospect of being fast-moving in downward rushes, and deadlier.

Phuket holidaymakers shouldn't complain too loudly about the weather today. People in neighboring provinces are enduring a struggle, in some cases, to stay above water.

The provinces of Nakhon Si Thammarat, Chumphon, Suratthani, Ranong, Phang Nga, Phattalung, Trang and Krabi are all under threat today, with rain forecast across the entire region.

Because movement from one province to another is becoming more difficult by the hour, it's not easy to see first-hand what kind of damage is being caused. As the rain eases in some provinces, it is intensifying in others.

Hundreds if not thousands of people are likely to be evacuated if the rain continues to fall the way it has for the past four days.

In Nakhon today, the rain shows no sign of stopping. The forecast is it will keep tumbling all the way through until Friday . . . and that would be disastrous.