ROANOKE, Va – Beyond the obvious reasons for wanting to get the trapped soccer team out as soon as possible, there are other reasons why time is not a luxury rescuers have. The brave men and women carrying out this rescue mission are fighting the weather in their efforts to save the team that went missing in the flooded cave more than two weeks ago. July starts monsoon season in Thailand. The monsoon isn't a singular weather event like a hurricane or a tornado, but rather a season.
The monsoon is generated by air circulations due to the fact water and land heat differently. The land gets hotter than the surrounding water, creating differences in pressure. This pressure difference then induces the monsoon circulation.
Low pressure develops over the warmer land and high pressure develops over the cooler ocean. Air flows from high to low pressure. Air then tends to rise with low pressure and sink with high pressure.
This is much like the daily thunderstorm cycle at the beach. The wind blows inland during the afternoon (sea breeze) generating storms inland at peak heating. You may notice the puffy cumulus clouds turn into storms on what was a crystal clear summer day. The opposite is true at night since the land then cools faster than the water. The breeze then goes back out to sea (land breeze) since the high pressure now resides over the relatively cooler land with the low pressure over the warmer waters.
The monsoon occurs on a much larger scale. As the wind blows from the ocean to the land, tropical moisture is transported inland resulting in very heavy rain. Once the land is routinely hotter than the water, usually in the late summer to early fall, the monsoon circulation can be generated.
This heavy rain often times leads to dangerous flash flooding. Mountainous terrain in this part of the world enhances the flash flood threat. The cave system the soccer team is trapped in is susceptible to the flash flooding created by the relentless tropical rain.
Over the next few days, several inches of rain is possible at the cave site in Chiang Rai in northern Thailand. Since on and off heavy rain is possible over the next several months, rescuers have to work quickly before the flooding inside of the cave gets worse.