Kochi: IMD has stated that conditions are favourable for further advance of monsoon over some parts of south Arabian Sea, Maldives and Comorin area in the next four days. Trough from Saurashtra to east-central Arabian Sea across northeast Arabian Sea persists above mean sea level.

An upper air cyclonic circulation lies over Andaman Sea, tilting southwestwards with height. A trough runs from west Vidarbha to north Kerala across Marathwada and interior Karnataka above mean sea level. Upper air cyclonic circulation over southern parts of Marathwada and its neighbourhood, extending above mean sea level, has merged with the above trough.According to 24-hour rainfall recorded on Monday morning, Urumi received 6cm, while Mavelikkara and Vellathooval got 3cm. A thunderstorm accompanied by lightning and gusty winds with speeds reaching 40-50 kmph is very likely to occur at one or two places over Kerala on Wednesday. IMD has issued a heavy rainfall alert for May 14, 18 and 19. Squally winds with speeds of 45-50 kmph, gusting to 55 kmph, are likely to prevail over south Tamil Nadu coast, Gulf of Mannar and adjoining Comorin area.Yellow alert has been sounded for Thiruvananthapuram, Pathanamthitta, Kozhikode and Wayanad on Wednesday.INCOIS has issued a swell surge alert for coastal regions of Alappuzha, Ernakulam, Kannur, Kasaragod, Kollam, Kozhikode, Malappuram, Thiruvananthapuram and Thrissur. Swell waves in the range of 14.0 - 17.0 seconds period with 0.5 - 0.6m height are forecast until 11.30pm on Wednesday. It advised that there is a possibility of surging waves, and boats should ply with utmost vigilance and recreation should be undertaken with due care.