Tropical Storm Polo weakened over northwestern Mexico after making a second landfall and drenching the Baja California peninsula, while a strengthening Tropical Storm Rachel churned offshore, threatening more dangerous weather for Mexico's Pacific coast. Polo again came ashore earlier on Tuesday near the port city of Guaymas as a Category 1 hurricane after crossing the peninsula the day before. Polo's maximum sustained winds had fallen to 100 kilometres per hour with rapid weakening expected as it pushes farther inland. Though Polo is fading, forecasters warned its moisture could continue fueling heavy rain well beyond Mexico. The US National Hurricane Center said Polo could dump 10 to 15 centimetres across southern and central Sonora state, raising the risk of life-threatening flooding and mudslides. Private forecaster AccuWeather said Polo's remnants could help trigger a broader deluge across the US Southwest and Plains.