Subject:
- A Well-marked Low Pressure area lay over southeast Arabian Sea and another Well-marked Low Pressure area lay over southwest Bay of Bengal.
- Heavy to very heavy rainfall (7-20 cm) over south peninsular India during 21st-24th with extremely heavy falls (≥ 21 cm) over Tamil Nadu on 21st & 22nd and over Kerala on 22nd October, 2025.
Realised Weather (Past 24 Hours till 0830 hours IST, 21st October 2025):
- Heavy to very heavy rainfall (7-20 cm) recorded at isolated places over Tamil Nadu, Puducherry.
- Heavy rainfall (7-11 cm) recorded at isolated places over Kerala, Rayalaseema, Coastal & South Interior Karnataka.
- For details, refer to ANNEXURE I.
Weather Systems, Forecast, and Warnings:
Weather Systems (Refer to ANNEXURE II & III):
- Yesterday’s Well-marked Low Pressure area over southeast Arabian Sea persisted at 0830 hrs IST of 21st October 2025. Likely to move westwards and intensify into a depression within 24 hours.
- A low-pressure area formed over southwest Bay of Bengal at 0530 hrs IST, becoming a Well-marked Low Pressure area by 0830 hrs IST on 21st October 2025. Likely to intensify into a depression by afternoon of 22nd October 2025 and move west-northwestwards towards north Tamil Nadu, Puducherry, and south Andhra Pradesh coasts, intensifying further in the subsequent 24 hours.
- An upper air cyclonic circulation over south Andaman Sea between lower and middle tropospheric levels.
- A Western Disturbance as a trough in middle and upper tropospheric westerlies runs along Long. 68°E to the north of Lat. 25°N.
Weather Forecast:
South Peninsular India:
- Light to moderate rainfall/thunderstorm at many/some places with isolated heavy rainfall over Tamil Nadu, Puducherry, Coastal & South Interior Karnataka during 21st-24th; Kerala, Coastal Andhra Pradesh & Yanam, Rayalaseema during 21st-27th; North Interior Karnataka on 23rd & 24th; Telangana during 23rd-25th with very heavy rainfall over Coastal Andhra Pradesh & Yanam, Rayalaseema during 21st-23rd; South Interior Karnataka on 21st & 22nd, Tamil Nadu on 23rd, Kerala on 21st & 23rd, and Coastal Karnataka on 22nd & 23rd October.
- Extremely heavy rainfall (≥ 21 cm) very likely over Tamil Nadu on 21st & 22nd and Kerala on 22nd October.
- Thunderstorm with lightning likely over the region during the next 5 days.
East & Central India:
- Light to moderate rain/thunderstorm at many places with isolated heavy rainfall over Andaman & Nicobar Islands during 21st-27th and Odisha on 25th & 26th October.
- Thunderstorm with lightning and gusty winds (30-50 kmph) likely over Andaman & Nicobar Islands during 21st-27th; Odisha during 21st-25th; and with lightning over Madhya Pradesh, Vidarbha, and Chhattisgarh during 21st-25th October.
West India:
- Thunderstorm with lightning likely over Konkan & Goa, Marathawada, and Madhya Maharashtra during the next 5 days.
North India:
- Thunderstorm with lightning likely over Uttarakhand on 22nd and Himachal Pradesh on 21st & 22nd October.
Warnings for Arabian Sea, Lakshadweep & Comorin Area, and Coastal Regions:
Wind Warning:
- Squally weather (35-45 kmph gusting to 55 kmph) likely over Southeast and adjoining Southwest & Eastcentral Arabian Sea, Lakshadweep & Comorin Area, and along & off Karnataka, Kerala, and adjoining South Tamil Nadu coasts till 24th October. Likely to increase to 40-50 kmph gusting to 60 kmph from the evening of 21st October over central parts of south Arabian Sea and adjoining central Arabian Sea on 22nd & 23rd October.
Sea Condition:
- Moderate to rough seas over Southeast and adjoining Southwest & Eastcentral Arabian Sea, Lakshadweep & Comorin Area, and along & off Karnataka, Kerala, and adjoining South Tamil Nadu coasts. Likely to become rough to very rough from the evening of 21st October over central parts of south Arabian Sea and adjoining central Arabian Sea on 22nd & 23rd October.
Fishermen Warnings:
- Fishermen are advised not to venture into Southeast & adjoining Eastcentral Arabian Sea, Lakshadweep & Comorin Area, and along & off Karnataka, Kerala, and adjoining South Tamil Nadu coasts till 21st October, and over central parts of south Arabian Sea and adjoining central Arabian Sea during 22nd to 23rd October 2025.
Warnings for Bay of Bengal and South Andaman Sea:
Wind Warning:
- Squally wind (40-50 kmph gusting to 60 kmph) prevailing over southwest Bay of Bengal and adjoining areas of southeast & central Bay of Bengal, increasing to 50-60 kmph gusting to 70 kmph over Southwest and adjoining Westcentral Bay of Bengal during 22nd to 24th October. Along & off Tamil Nadu & south Andhra Pradesh coasts, squally winds (35-45 kmph gusting to 55 kmph) likely to increase to 40-50 kmph gusting to 60 kmph on 22nd and 50-60 kmph gusting to 70 kmph during 23rd to 24th October. Squally weather (35-45 kmph gusting to 55 kmph) over Andaman Sea and remaining parts of South Bay of Bengal till 25th October.
Sea Condition:
- Rough seas over southwest Bay of Bengal and adjoining areas of southeast & central Bay of Bengal, likely to become rough to very rough till 24th October. Rough seas along & off Tamil Nadu & south Andhra Pradesh coasts, likely to become rough to very rough till 23rd October. Moderate to rough seas over Andaman Sea and remaining parts of South Bay of Bengal till 25th October.
Fishermen Warning:
- Fishermen are advised not to venture into South and adjoining central Bay of Bengal till 24th October. Those at sea should return to the coast.
Weather Conditions and Forecast for Delhi/NCR (21st to 24th October 2025):
Past Weather:
- Rise in minimum temperature by 1–2°C, no significant change in maximum temperature. Maximum temperatures: 31–33°C; Minimum temperatures: 20–22°C (above normal by 2–4°C). Moderate fog at Safdarjung airport (lowest visibility 400 m at 0730 hours IST, improving to 500 m at 0800 hours IST). Palam airport recorded lowest visibility 600 m from 0330 to 0500 hours IST, improving to 700 m at 0530 hours IST. Mainly clear skies with northeast winds (up to 08 kmph) prevailed. Partly cloudy skies with haze/mist and calm winds increasing to 08 kmph from southeast in the forenoon.
Weather Forecast:
- 21.10.2025: Partly cloudy sky with mist/haze from noon. Max/min temperatures: 31–33°C/near normal. East winds up to 00–05 kmph in the afternoon, decreasing to <05 kmph in the evening/night.
- 22.10.2025: Smog/shallow fog at many places, moderate fog at isolated places in the morning, becoming partly cloudy with mist/haze from noon. Max/min temperatures: 32–34°C/19–21°C (min above normal by 1–3°C). West winds 05–10 kmph in the morning, increasing to <12 kmph from northwest in the afternoon, decreasing to <08 kmph from north in the evening/night.
- 23.10.2025: Smog/shallow to moderate fog at many places in the morning, becoming mainly clear with mist/haze from noon. Max/min temperatures: 31–33°C/18–20°C (min above normal by 1–2°C). Northwest winds 00–05 kmph in the morning, increasing to <12 kmph in the afternoon, decreasing to <10 kmph from north in the evening/night.
- 24.10.2025: Smog/shallow fog at many places in the morning, becoming mainly clear with mist/haze from noon. Max/min temperatures: 32–34°C/18–20°C (min above normal by 1–2°C). North winds 00–05 kmph in the morning, increasing to <06 kmph in the afternoon.
Impact & Action Suggested:
Extremely Heavy Rainfall (Tamil Nadu: 21st & 22nd; Kerala: 22nd October):
Very Heavy Rainfall: Tamil Nadu, Kerala (21st–24th); Coastal Karnataka (22nd & 23rd); South Interior Karnataka (21st & 22nd); Coastal Andhra Pradesh & Yanam, Rayalaseema (21st–23rd).
Impact Expected:
- Localized flooding of roads, waterlogging in low-lying areas, and closure of underpasses in urban areas.
- Occasional reduction in visibility due to heavy rainfall.
- Traffic disruption in major cities due to waterlogging, increasing travel time.
- Minor damage to kutcha roads.
- Possible damage to vulnerable structures.
- Localized landslides/mudslides/landslips/mudsinks.
- Damage to horticulture and standing crops due to inundation.
- Possible riverine flooding in some river catchments (Bihar, Jharkhand, West Bengal; refer to CWC webpage).
Action Suggested:
- Check for traffic congestion before leaving.
- Follow traffic advisories.
- Avoid areas prone to waterlogging.
- Avoid staying in vulnerable structures.
Agromet Advisories for Heavy Rainfall:
- Tamil Nadu: Store harvested rice and groundnut in safe places. Drain excess water from rice, cotton, black gram, maize, tapioca, vegetables, and plantations (coconut, banana, black pepper).
- Kerala: Store harvested rice in safe places. Drain excess water from rice, vegetables, and plantations (banana, coconut, arecanut, cardamom, black pepper).
- Andhra Pradesh: Harvest matured groundnut and maize cobs during fair weather, store safely. Provide drainage for rice, maize, pigeon pea, black gram, green gram, groundnut, turmeric, ginger, vegetables, and plantations (banana, coconut, arecanut).
- Coastal Karnataka: Drain excess water from rice and plantations (coconut, arecanut, black pepper).
- South Interior Karnataka: Store harvested groundnut and maize in dry, covered areas. Harvest rice, pulses, vegetables, cardamom, and coffee during dry intervals, store in ventilated, moisture-free places. Drain excess water from rice, maize, finger millet, pulses, groundnut, vegetables, and plantations (banana, black pepper, cardamom, coffee, coconut, arecanut).
- Andaman and Nicobar Islands: Store harvested paddy safely. Arrange drainage for paddy, vegetable, and plantation crops.
Livestock/Fishery Advisories:
- Keep animals inside sheds during heavy rainfall, provide balanced feed.
- Store feed and fodder in safe places to prevent spoilage.
- Construct outlets with netting around ponds to prevent fish escape due to overflow.
Thunderstorm/Gusty Winds/Squally Winds Advisories:
- Provide mechanical support to horticultural crops and staking for vegetables/young fruit plants to avoid lodging.
- Tie and cover harvested crops to minimize displacement due to strong winds.
Flash Flood Guidance (Till 1130 IST, 22nd October 2025):
Low to Moderate Flash Flood Risk:
- Kerala & Mahe: Ernakulam, Idukki, Kottayam, Palakkad, Thrissur districts.
- Tamil Nadu, Puducherry & Karaikal: Karaikal, Puducherry, Ariyalur, Coimbatore, Cuddalore, Dharmapuri, Kanchipuram, Karur, Nagapattinam, Namakkal, Perambalur, Pudukkottai, Sivaganga, Thanjavur, Thiruvarur, Tiruchirappalli, Tiruppur, Tuticorin, Virudhunagar districts.
- Surface runoff/inundation may occur in fully saturated soils and low-lying areas due to expected rainfall in the next 24 hours.
ANNEXURE I: Rainfall Recorded (≥ 7 cm, Past 24 Hours till 0830 hours IST, 21st October):
- Tamil Nadu, Puducherry & Karaikal: Thangachimadam (Ramanathapuram) 17 cm; Pamban (Ramanathapuram) 15 cm; Mandapam (Ramanathapuram) 14 cm; Varattupallam (Erode) 13 cm; Chidambaram, Chidambaram AWS, Annamalai Nagar (Cuddalore), Velankanni (Nagapattinam) 10 cm each; Nagapattinam, Karaikal, Rameswaram (Ramanathapuram), Tirupoondi (Nagapattinam) 9 cm each; Thalaignayer (Nagapattinam), Ayyampettai (Thanjavur), Sholinganallur (Chennai), Vettikadu (Thanjavur) 8 cm each; Parangipettai (Cuddalore), Mayiladuthurai, Sirkali (Mayiladuthurai), Tiruvarur 7 cm each.
- Kerala & Mahe: Neyyattinkara (Thiruvananthapuram) 11 cm; Quilandi (Kozhikode) 9 cm; Irinjalakuda (Thrissur), Piravam (Ernakulam) 7 cm each.
- Rayalaseema: Sullurpeta (Tirupati) 7 cm.
- Coastal Karnataka: Dakshina Kannada_Bantwal_Kavalamuduru 8 cm.
- South Interior Karnataka: Hassan_Alur 7 cm, Chikkamagaluru_Kadur_Kadur(Rural) 7 cm.
ANNEXURE II & III:
- Forecast accuracy decreases as lead period increases.
- Take action based on ORANGE and RED colour warnings.
- Initiate action for heavy rainfall warnings in vulnerable urban and hilly areas.
- Detailed district-wise multi-hazard weather warnings for the next five days: District Wise Warning.
Additional Resources:
- National Weather Bulletin: View Bulletin
- District-wise Warnings: View Warnings
- Fishermen Warnings: View Fishermen Warnings