Is Singapore cloud-seeding dangerous rain to clear the haze and ensure this weekend's F1 Grand Prix event goes ahead smoothly, as a recently circulating text message is alleging?

The short answer is no.

Minister for the Environment and Water Resources Vivian Balakrishnan on Thursday refuted the rumour on his Facebook page, declaring that Singapore did not and does not plan to induce rain because any attempt would be met with failure anyway:

The issue has also been clarified on a government website.

From Factually:

The National Environment Agency (NEA) is aware that there is an SMS rumour being circulated suggesting that the Government is conducting cloud-seeding to mitigate the impact of haze on F1, and that the resultant rain from this is harmful. These claims are untrue.

The Government has not been conducting cloud-seeding and has no plans to do so. Cloud seeding attempts to artificially induce rain by implanting clouds with suitable particles. However, there are no reliable means to validate the effectiveness of cloud seeding in Singapore. Cloud seeding also requires existing clouds as it cannot generate rain out of thin and dry air. During dry seasons, cloud seeding is less effective due to the lack of suitable clouds for seeding. The small size of Singapore and the variability of winds also mean that the induced rain, if any, may not fall directly over our island.

Conclusion: Please stop spreading nonsense text messages, kthxbye.