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The Philippines is exposed to tropical cyclones (TCs) throughout the year due to its location in the western North Pacific. While these TCs provide muchneeded precipitation for the country's hydrological cycle, extreme precipitation from TCs may also cause damaging hazards such as floods and landslides. This study examines the relationship between TC extreme precipitation and TC characteristics, including movement speed, intensity and season, for westward-moving TCs crossing Luzon, northern Philippines. We measure extreme precipitation by the weighted precipitation exceedance (WPE), calculated against a 95th percentile threshold, which considers both the magnitude and spatial extent of TC-related extreme precipitation. WPE has a significant, moderate positive relationship with TC intensity with a non-significant, weak negative relationship with movement speed. When TCs are classified by intensity 1 day before landfall (or pre-landfall), Typhoons (1-min maximum sustained wind speed ≥64 knots) tend to yield higher WPE than non-Typhoons (<64 knots). On the other hand, when TCs are classified by pre-landfall speed, slow TCs (movement speed <11.38 knots) tend to yield higher WPE than fast TCs (movement speed ≥11.38 knots). However, the relationship between prelandfall TC intensity and WPE is more pronounced during June–September while there is no significant difference between the WPE of the southwest monsoon (June–September) and northeast monsoon (October–December) seasons. These results suggest that it is important to consider the pre-landfall cyclone movement speed, intensity and season to anticipate extreme precipitation of incoming TCs. A decision table considering these factors is devised to aid in TC extreme precipitation forecasting. [ABSTRACT FROM AUTHOR]

The west coast of India, dominated by the Western Ghats mountain range, is among the rainiest places in the Tropics. The interaction between the land–sea contrast of the coast, the monsoonal westerlies, and the oblique mountains is subject to complex intraseasonal variability, which has not previously been explored in depth. This study investigates that variability from the perspective of the land–sea contrast, using empirical orthogonal function analysis to discern regimes of onshore and offshore rainfall over southwest India and the eastern Indian Ocean. Locally, it is found that the rainfall is most sensitive to midtropospheric humidity: when this is anomalously high, deep convection is encouraged; when this is anomalously low, it is suppressed. A moisture‐tracking algorithm is employed to determine the primary sources of the anomalously wet and dry midtropospheric air. There are important secondary contributions from low‐level vorticity and cross‐shore moisture flux. The dominant control on intraseasonal variability in coastal precipitation is found to be the Boreal Summer Intraseasonal Oscillation (BSISO): over 75% of the strongest offshore events occur during phases 3 and 4; and about 40% of the strongest onshore events occur during phases 5 and 6. The location of monsoon low‐pressure systems is also shown to be important in determining the magnitude and location of coastal rainfall. [ABSTRACT FROM AUTHOR]