Cyclone Dana: A Brewing Storm Over Bay of Bengal Threatens Odisha
As the northeast monsoon prepares to bring much-awaited rains to South India, the Bay of Bengal, often ominously referred to as the “Bay of Sorrows,” is signaling the potential development of a severe cyclonic storm. The India Meteorological Department (IMD) has warned of a brewing low-pressure system, which could escalate into a cyclonic storm, potentially making landfall near Chennai by October 17, 2024.
This article delves into the formation, forecasts, potential impacts, and warnings surrounding Cyclone Dana, offering an in-depth analysis of how this developing storm could affect the coastal regions of Tamil Nadu, Andhra Pradesh, and beyond.
Formation of the Cyclonic System: Low-Pressure Brewing in the Bay of Bengal
The Bay of Bengal has a notorious reputation for cyclonic activity, particularly during the post-monsoon season. With the northeast monsoon looming, the Bay is now the center of attention once again as meteorologists track the formation of a low-pressure system. According to IMD reports, there is a moderate chance of cyclogenesis (the process of a tropical depression transforming into a cyclone) within the next 48 to 72 hours.
A key factor influencing this cyclonic activity is the Madden-Julian Oscillation (MJO), a major driver of tropical weather systems. The MJO, currently in its active phase (phase 4), is expected to enhance convective activity over the Bay of Bengal. This, in turn, could amplify the low-pressure system into a more organized storm, potentially escalating into a severe cyclonic storm.
While cyclogenesis is a common occurrence in the Bay of Bengal during this time of year, the IMD’s Global Forecast System (GFS) model has predicted that this system could intensify rapidly, raising concerns about its strength as it nears landfall.
Forecast Models: Diverging Predictions on Storm Intensity and Path
Meteorologists across the globe are closely monitoring this evolving system, but not all forecasts are in agreement. Various weather prediction models offer differing scenarios regarding the potential intensity and path of the storm.
- IMD GFS Prediction: The IMD’s GFS model is one of the more aggressive forecasts, indicating that the low-pressure area could rapidly intensify into a severe cyclonic storm by October 16. According to the GFS, the storm would approach the shores of South Andhra Pradesh, North Tamil Nadu, and Puducherry before making landfall as a strong cyclonic storm close to Chennai on October 17.According to the GFS, the storm would approach the shores of South Andhra Pradesh, North Tamil Nadu, and Puducherry before making landfall as a strong cyclonic storm close to Chennai on October 17.
- European Model (ECMWF): The European model ECMWF, widely regarded for its accuracy in cyclone forecasting, presents a more conservative outlook. According to ECMWF, the system will remain a well-marked low-pressure area, moving west-northwestwards before crossing the South Andhra Pradesh coast. The ECMWF does not foresee any significant intensification beyond a low-pressure system.
- TWC Meteorologists and NCUM Group of Models: Other models, including the TWC meteorologists and NCUM group of models, suggest that the system will intensify up to a depression but not develop into a full-blown cyclone. These models predict that the system will approach the coastal regions of Tamil Nadu and Andhra Pradesh by Thursday, October 17, and stall there until Friday.
Cyclone Dana: The Naming Convention and Potential Strength
If the system intensifies into a cyclone, it will be named Cyclone Dana, following the guidelines of the World Meteorological Organisation (WMO) for naming cyclones in the region. The name “Dana” was proposed by Qatar.
While the exact intensity of the storm remains uncertain, the IMD’s GFS model has forecasted the possibility of the system escalating into a severe cyclonic storm with wind speeds potentially exceeding 100 km/h. If this forecast holds, Cyclone Dana could bring widespread devastation to the coastal areas of Tamil Nadu and Andhra Pradesh, particularly in regions near Chennai.
Weather Warnings and Alerts: Preparing for the Worst
In anticipation of the brewing storm, the IMD has issued a series of warnings and alerts for the affected regions:
- Red Alert for October 16: A red alert, which signifies “take action,” has been issued for Coastal Andhra Pradesh, Tamil Nadu, and Puducherry on October 16. This alert warns of extremely heavy rainfall in these regions, with rainfall exceeding 20 cm in some areas.
- Orange Alert for October 15 and 17: An orange alert, meaning “be prepared,” has been issued for October 15 and 17. This alert applies to parts of Tamil Nadu and Puducherry, where heavy to very heavy rainfall is expected.
- District-Wise Warnings: Within Tamil Nadu, several districts, including Tiruvallur, Chennai, Kancheepuram, Chengalpattu, Cuddalore, Villupuram, Mayiladuthurai, Nagapattinam, and Tiruvarur, are under a red warning for October 16. Puducherry and Karaikal are also included in this red warning zone.
Impacts of Cyclone Dana: Potential for Widespread Rainfall and Flooding
If Cyclone Dana intensifies as predicted, the coastal regions of Tamil Nadu, Andhra Pradesh, and Puducherry are likely to experience significant impacts. The IMD has forecasted widespread rainfall across these areas over the next few days, with the heaviest downpours expected on October 16.
1. Rainfall Predictions:
The storm is expected to bring heavy to extremely heavy rainfall to several districts, with the potential for flash flooding in low-lying areas. Rainfall could exceed 20 cm in some regions, particularly in Chennai and surrounding districts.
2. Wind Speeds and Squally Weather:
Squally weather is expected along the coasts of Tamil Nadu, Puducherry, and South Andhra Pradesh. Wind speeds are predicted to reach 40-50 km/h, with gusts up to 60 km/h, potentially causing damage to trees, power lines, and weak structures.
3. Sea Conditions:
Moderate to rough sea conditions are likely to prevail in the southeast, southwest, and central Bay of Bengal. As the system intensifies, sea conditions could worsen, leading to dangerous waves and storm surges along the coast. Fishermen have been advised to stay ashore until October 17, as the seas will remain treacherous for small boats.
Possible Cyclone Dana: International Meteorological Perspectives
Weather agencies from around the world are also closely monitoring the development of this system. Forecasts from the United States and European Union weather models suggest that there is a high probability of cyclogenesis occurring between October 21 and 26.
- The European Union Weather Forecast Model indicates that there is a 70%–80% probability of cyclone formation during this time frame. Should the storm intensify, it is anticipated to reach landfall between October 24 and 26 in the coastal regions of Bangladesh and India.The European Union Weather Forecast Model indicates that there is a 70%–80% probability of cyclone formation during this time frame. Should the storm intensify, it is anticipated to reach landfall between October 24 and 26 in the coastal regions of Bangladesh and India.
- American Weather Models: American weather models have also indicated a similar timeframe for cyclone formation, predicting the likelihood of a storm hitting the eastern coast of India, particularly the Barishal Bangladesh and the Indian state of Odisha are divided.
Both models emphasize the uncertainty in the storm’s path and intensity, but they agree that a significant weather event is likely to unfold over the Bay of Bengal in the coming days.
Preparations in Coastal Regions: Evacuations and Emergency Measures
As the potential landfall of Cyclone Dana approaches, authorities in Tamil Nadu, Andhra Pradesh, and Puducherry are ramping up preparations to mitigate the storm’s impacts.
- Evacuations: Coastal communities in low-lying areas are being evacuated to safer locations. Emergency shelters have been set up, and relief supplies, including food, water, and medical aid, are being stockpiled in anticipation of the storm.
- School and Office Closures: The Tamil Nadu government has declared holidays for schools and colleges in Chennai, Tiruvallur, Kancheepuram, and Chengalpattu districts. Private offices have been advised to allow employees to work from home or operate with minimal staff during the storm period.
- Essential Services: Essential services, including police, fire and rescue, municipal administration, and transportation of essential goods, will continue to operate. However, public transport services may be suspended in some areas due to flooding and road blockages.
The Aftermath: What Happens Next?
If Cyclone Dana makes landfall near Chennai as a severe cyclonic storm, the aftermath could be devastating. Coastal flooding, widespread power outages, and extensive damage to infrastructure are likely outcomes. Relief and rehabilitation efforts will be critical in the days following the storm, as authorities work to restore normalcy in the affected regions.
The IMD will continue to monitor the system’s development and provide regular updates. Residents of Tamil Nadu, Andhra Pradesh, and Puducherry are urged to stay informed, follow official advisories, and take necessary precautions to ensure their safety.
Conclusion
As the Bay of Bengal signals the birth of a potentially severe cyclone, the coastal regions of South India are on high alert. With Cyclone Dana looming on the horizon, the coming days will be crucial in determining the storm’s path and intensity. While various models offer differing predictions, the consensus is clear: a significant weather event is likely to unfold, bringing heavy rainfall, strong winds, and dangerous sea conditions to Tamil Nadu, Andhra Pradesh, and beyond.
In the face of this brewing storm, preparedness and vigilance will be key to minimizing its impacts and ensuring the safety of the affected communities. As the IMD and other international meteorological agencies continue to track the system, the people of South India must remain alert and ready to act in response to the evolving situation.
India’s weather systems and forecast for October 19–25, 2024
Cyclonic Circulations and Low-Pressure Areas
Cyclonic Circulation over Arabian Sea:
The cyclonic circulation that was centered on the North Lakshadweep region yesterday has moved to the east-central Arabian Sea. It extends up to 5.8 km above sea level.
Within the next twelve hours, a low-pressure area is predicted to form in the same location. Over the following three days, it is anticipated to intensify and travel away from the Indian coast and to the west-northwest.
Trough across Karnataka and Rayalaseema:
A trough extends from the cyclonic circulation over the east-central Arabian Sea to the South Andhra Pradesh coast, crossing Karnataka and Rayalaseema, up to 3.1 km above sea level.
Cyclonic Circulation over Andaman Sea:
A new upper air cyclonic circulation is expected to form over the North Andaman Sea around October 20th, potentially leading to the formation of a low-pressure area over the Central Bay of Bengal around October 22nd. This system is likely to intensify into a depression by October 24th as it moves northwestward.
Regional Weather Forecast and Warnings (19th – 25th October)
South Peninsular India
Rainfall: Over Tamil Nadu, Puducherry & Karaikal, Kerala & Mahe, Lakshadweep, Coastal Karnataka, South Interior Karnataka, and Rayalaseema, there is a chance of light to moderate rainfall that is scattered to quite widespread. There will be sporadic to isolated downpours over the remainder of the region.
Heavy Rainfall: Isolated heavy rainfall is expected over Tamil Nadu, Puducherry & Karaikal from October 19th to 21st and again on October 24th. Other areas that are probably going to have a lot of rain are:
North Interior Karnataka: October 19th to 22nd.
South Interior Karnataka: October 19th to 23rd.
Rayalaseema: October 19th.
Kerala & Mahe: October 20th to 24th.
Coastal Andhra Pradesh & Yanam: October 19th, 20th, 24th, and 25th.
Coastal Karnataka: October 22nd and 23rd.
East India
Rainfall: Over the Andaman and Nicobar Islands, widespread light to average rainfall is predicted. There will be sporadic to isolated mild to moderate rainfall over the rest of East India.
Heavy Rainfall: Sporadic heavy downpours are anticipated over:
Andaman & Nicobar Islands: October 19th to 21st, with very heavy rainfall on October 20th and 21st.
Gangetic West Bengal: October 23rd to 25th.
Odisha: October 19th, 23rd to 25th, with very heavy rainfall on October 24th and 25th.
West India
Rainfall: Over the Konkan and Goa, Madhya Maharashtra, and isolated regions of the region, scattered to fairly widespread mild to moderate rainfall is likely. Dry weather will prevail in Saurashtra & Kutch from October 22nd to 25th.
Severe Rain: Sporadic heavy downpours are anticipated in:
Konkan & Goa, Madhya Maharashtra, Saurashtra & Kutch, and Gujarat Region on October 19th and 20th.
Hailstorm: Likely in Madhya Maharashtra and Marathwada on October 19th and 20th.
Northwest, Central & Northeast India
Rainfall: Throughout the week, no appreciable amount of rain is predicted for these areas.
Rainfall Summary (from 08:30 IST of 18th October to 08:30 IST of 19th October):
Widespread Rainfall: Konkan & Goa, Rayalaseema.
Heavy Rainfall: Isolated heavy to very heavy rainfall was recorded in:
Odisha, Tamil Nadu, Puducherry & Karaikal, Rayalaseema, Gujarat Region, Madhya Maharashtra, Marathwada, and Coastal Andhra Pradesh & Yanam.
Temperature Summary (as of 19th October 2024):
Lowest Minimum Temperature: Sikar (East Rajasthan) reported the lowest minimum temperature of 16.2°C.
Highest Maximum Temperature: The highest temperature of 39.9°C was recorded at Pokharan, Rajasthan.
Detailed Weather Alerts (19th to 25th October 2024)
19th October (Day 1):
Heavy Rainfall: Very likely over Tamil Nadu, Puducherry & Karaikal, Andaman & Nicobar Islands, Odisha, Konkan & Goa, Madhya Maharashtra, and Rayalaseema.
Thunderstorms & Hail: Thunderstorms with lightning and hail are expected over Madhya Maharashtra and gusty winds over Telangana. Lightning is likely over Madhya Pradesh, Odisha, and various regions across South India.
Squally Weather: Wind speeds of 35-45 km/h, gusting up to 55 km/h, are likely off Maharashtra’s coast and over the Arabian Sea. It is advised that fishermen avoid these regions.
20th October (Day 2):
Heavy Rainfall: Likely over Andaman & Nicobar Islands, Konkan & Goa, and Tamil Nadu.
Thunderstorms: Expected over Madhya Maharashtra, with gusty winds over Telangana and lightning across multiple regions.
21st October (Day 3):
Heavy Rainfall: Very likely over Andaman & Nicobar Islands, Tamil Nadu, Puducherry, and Kerala.
Thunderstorms: Most likely over interior Karnataka, Vidarbha, and Telangana.
22nd October (Day 4):
Heavy Rainfall: Isolated heavy rainfall expected over Kerala & Mahe, and Karnataka.
Squally Weather: Expected over Andaman Sea and Bay of Bengal, with wind speeds of 35-45 km/h.
23rd October (Day 5):
Heavy Rainfall: Likely over Gangetic West Bengal, Odisha, and Kerala.
24th October (Day 6):
Very Heavy Rainfall: Likely over Odisha, with heavy rainfall in Tamil Nadu, Puducherry, and Coastal Andhra Pradesh.
25th October (Day 7):
Very Heavy Rainfall: Expected in Odisha and Gangetic West Bengal.
Impact-Based Forecast:
Residents in affected areas, particularly Tamil Nadu, Puducherry, Andaman & Nicobar Islands, Odisha, and Gangetic West Bengal, should be prepared for heavy to very heavy rainfall and possible localized flooding.
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