Cyclone Arnab's Impact: Rains in Delhi, Flooding in Andhra Pradesh and Odisha, Weather Changes up to Bihar and Jharkhand

Air pollution levels have begun to rise in Delhi-NCR against the backdrop of approaching cold weather. In the capital, despite sunny days and dropping night temperatures, the air reached poor quality for the first time this season on Wednesday. Simultaneously, due to the low-pressure area in the Bay of Bengal and other atmospheric phenomena, rainfall is forecasted in various parts of the country. The Meteorological Department issued a rain warning for 15 states for October 22.

Temperatures in the plains are decreasing under the influence of snow in the mountainous regions and cold winds, leading to an increased feeling of cold. According to meteorological service data, conditions favorable for rain are forming in eastern and southern India due to the low-pressure area in the Bay of Bengal and cyclonic circulation over Bangladesh. Furthermore, the influence of Western Disturbances is causing rain and snowfall in hilly states, while light rains have been recorded in some plain areas. The drop in temperature due to precipitation and cold winds enhances the feeling of cold in the morning and evening.

As winter sets in, air quality in Delhi-NCR has started to deteriorate. In the capital, on Wednesday, October 21, the Air Quality Index (AQI) was 245, marking the first day with poor air quality this season. After reaching the poor quality category, the Central Pollution Control Board (CPCB) implemented the first stage of the Graded Response Action Plan (GRAP) for Delhi-NCR.

Previously, the AQI in Delhi had reached 246 on July 13. Analysis of data by the Centre for Research on Energy and Clean Air (CREA) showed that from 2015 to 2025, the air in Delhi typically fell into the poor quality category in the first ten days of October. This year, it happened on October 21, which is the latest instance among available data. According to the air quality early warning system, the air in Delhi may remain in the poor category until October 23, and no significant improvement is expected in the forecast for the next six days.

Following the implementation of the first stage of GRAP in Delhi-NCR, steps are being taken to control dust at construction sites, mechanically clean roads, and increase water spraying. Open burning of garbage and organic waste is prohibited, and action will be taken against polluting vehicles. Inspections of industrial units, brick kilns, and hot mix plants will also be intensified. The Delhi Metro Rail Corporation (DMRC) announced the launch of 20 additional trains on weekdays starting Thursday as part of efforts to reduce pollution. The Delhi government also announced strict enforcement of the rule prohibiting the sale of fuel at petrol pumps without a Pollution Under Control (PUC) certificate, valid from November 1. Additionally, from November 1, only BS-VI standard vehicles will be allowed entry in Delhi, except for ambulances, electric vehicles, and other vehicles used for essential services.

The weather is also changing in Uttar Pradesh. In recent days, temperatures have dropped after light rains. According to meteorological forecasts, temperatures may drop further in the coming days, leading to increased cold in the morning and at night. Weather changes are possible in many areas, including Kanpur, Kushinagar, Bijnor, Agra, Mathura, Shravasti, Gorakhpur, Ghaziabad, Noida, Meerut, and Deoria, on October 22. Lucknow is forecasted to have a maximum temperature of about 31 degrees and a minimum of about 18 degrees Celsius. Temperature fluctuations may also be observed in areas adjacent to Delhi-NCR in western Uttar Pradesh.

The impact of the weather is felt more strongly in the hilly states. Fresh snow has fallen in the high-altitude areas of Rudraprayag and Chamoli in Uttarakhand, while light to moderate rain is forecasted in Haridwar and Rishikesh. Cold is also intensifying in the high-altitude regions of Himachal Pradesh and Jammu and Kashmir due to snowfall. Cold winds from the mountains can also be felt in the plains. A further drop in temperature is expected over the next two to three days. Among tourists in mountain tourism spots, there is an increase in visits amid the weather changes.

The weather is also changing in Madhya Pradesh and Rajasthan. Rain is forecasted near 21 districts of Madhya Pradesh and 20 districts of Rajasthan. Following recent rainfall in parts of both states, a decrease in temperature has been recorded. In Bhopal, a maximum temperature of about 31 degrees and a minimum of about 18 degrees Celsius is forecasted. In Jaipur, the maximum temperature is estimated at 23 degrees, and the minimum is about 19 degrees Celsius. Changes in daytime and nighttime temperatures may occur due to rain and cloud cover.

The Meteorological Department has issued a rain warning for October 22 for Tamil Nadu, Kerala, Karnataka, Telangana, Maharashtra, Lakshadweep, and other states.

As the second period of October begins, various weather phenomena are observed across different parts of the country. Heavy rain is forecast in some regions, while others expect strong winds with thunderstorms. In South India, the rainy season may intensify, while a low-pressure area in the Arabian Sea is activating sea weather.

Conversely, in the northern states of India, including Delhi, the cold has intensified in the morning, evening, and night. On Monday morning, Delhi recorded the coldest night of the month. The minimum temperature at the Safdarjung weather station was 17.1 degrees Celsius, which is 1.3 degrees below the average. Meanwhile, the daytime maximum temperature reached 31.7 degrees Celsius. According to the Meteorological Department (IMD), the minimum temperature recorded in Safdarjung is the lowest for the current month. In Delhi, as in other northern Indian states, light cold has begun to be felt during the morning, evening, and night hours.

The problem of air pollution may increase in the capital region in the coming days. According to the Central Pollution Control Board (CPCB), on Monday at 16:00, the average daily Air Quality Index (AQI) in Delhi was 139, which falls into the moderate category. Out of 58 monitoring stations, two were in the poor air quality category, six in the satisfactory category, and the rest in the moderate category. The worst situation was recorded in Pusa, where the AQI reached 281. Early warning system forecasts show that the air in Delhi may remain in the moderate category on October 20. However, pollution could rise to the poor category on October 21 and 22. There is a possibility of poor air quality persisting for the next six days. Adverse weather conditions can hinder the dispersion of pollutants. Pollution can accumulate in the air when the ventilation index is below 6000 square meters per second and the average wind speed is less than 10 kilometers per hour.

Amid concerns about air quality in Delhi, instances of stubble burning are also being recorded. Satellite data from the CREAMS laboratory of the Indian Council of Agricultural Research (ICAR-IARI) registered 98 cases of stubble burning in six states on October 19. Among these, there were 27 cases in Uttar Pradesh, 25 in Punjab, 24 in Rajasthan, 18 in Uttarakhand, and four cases in Madhya Pradesh. On Monday, no cases of stubble burning were registered in Haryana and Delhi. From September 15 to October 19, the total number of incidents was 1171. These incidents included 370 in Madhya Pradesh, 368 in Punjab, 197 in Rajasthan, 175 in Uttar Pradesh, 51 in Uttarakhand, 9 in Haryana, and 1 case in Delhi. CPCB classifies AQI categories as follows: good - 0-50, satisfactory - 51-100, moderate - 101-200, poor - 201-300, very poor - 301-400, and hazardous - 401-500.

In the northwestern part of Uttar Pradesh and surrounding areas, there is cyclonic rotation in the upper layers of the atmosphere at an altitude of about 1.5 kilometers above sea level. Nevertheless, the meteorological department does not predict major weather changes in North India different from the forecasts given for various states this week. A cyclonic rotation has formed over Himachal Pradesh and adjacent Punjab, associated with a western disturbance, at an altitude of about 3.1 kilometers above sea level. The corresponding trough line extends to an altitude of about 5.8 kilometers in the middle troposphere. Cyclonic rotation is also present in southern Rajasthan and surrounding areas. The trough line originated from southwestern Rajasthan to northeastern Arabian Sea. Despite these weather systems, the meteorological department does not forecast large-scale weather activity for North India.

Weather in some parts of central and western India may change after North India. In Madhya Pradesh, winds of 30-40 kilometers per hour with thunderstorms are expected in some places on October 20, with gusts potentially reaching 50 kilometers per hour. In Konkan and Goa, winds of 40-50 kilometers per hour with thunderstorms are possible on Tuesday, with gusts potentially reaching 60 kilometers per hour. Similar weather may be observed in central Maharashtra.

An increase in rainfall activity is expected in South India. IMD warned of heavy and very heavy rainfall in some areas of Tamil Nadu, Puducherry, and Karaikal on October 20. Heavy rains may also lash Kerala, Maharashtra, and coastal Andhra Pradesh. K.A. Sangothaiyan, Minister of Revenue and Disaster Management of Tamil Nadu, reported that an orange alert has been issued in six districts: Tiruvur, Mayiladuthurai, Thanjavur, Pudukkottai, Coimbatore, and Nilgiris. The minister told journalists at the emergency control center in Ajilagam, Chennai, that the district administration has been instructed to be prepared for heavy rains. District directors and officials from relevant departments are monitoring the situation and are ready to take immediate action if necessary. In Tamil Nadu, Puducherry, and Karaikal on October 20-25...

Weather conditions across the country will begin to change again. While the monsoon season is concluding in some regions, the northeast monsoon is preparing to start. At the same time, a Western Disturbance has begun to affect the weather in North India. Its impact threatens rain, strong winds, and hail in several states of North India, including Delhi-NCR. Furthermore, a period of heavy rains may begin in South India from October 15th.

According to the Meteorological Department (IMD), Thursday will bring predicted rain with thunderstorms in many parts of the country. According to the IMD forecast for October 15th, strong winds with rain are expected in the plains of Northwest India. On the other hand, a warning has been issued for heavy and very heavy rainfall in Tamil Nadu, Puducherry, Karaikal, Kerala, and Mahé. Heavy rains are also possible in some areas of coastal Andhra Pradesh and South Interior Karnataka. Thus, variable weather conditions can be expected in different parts of the country over the next few days.

The withdrawal of the southwest monsoon from the country continues. According to the meteorological department, on October 14th, the monsoon withdrawal line passed through Dhubri, Calcutta, Angul, Hammam, and Honavar. Conditions are becoming favorable for the further withdrawal of the monsoon from other regions. The southwest monsoon usually brings rain to most regions of the country from June to September. With the weakening and withdrawal of this monsoon, the northeast monsoon will become active in South India. During these changes, various weather phenomena may be observed simultaneously in different parts of the country.

In North India, weather changes continue under the influence of the Western Disturbance. In Delhi-NCR, after brief rains on October 14th, rain is forecasted in many areas on October 15th. The meteorological department reports that heavy or very heavy rain is possible in some places in Delhi, Haryana, Chandigarh, and Punjab. Additionally, there is a possibility of rain in several districts of Jammu and Kashmir, Ladakh, Himachal Pradesh, Uttarakhand, West Uttar Pradesh, and East Rajasthan.

Rain with hail can cause problems for the public. Hailfall is forecasted in some places in Haryana, Chandigarh, Delhi, Punjab, Uttarakhand, West Uttar Pradesh, and East Rajasthan. There is also a threat of lightning during thunderstorms in these areas. The meteorological department has also warned of strong winds. In Haryana, Chandigarh, Delhi, Punjab, and Uttarakhand, wind speeds may reach 40-50 kilometers per hour.

There is a possibility of wind gusts reaching 60 kilometers per hour. Winds of 30-40 kilometers per hour are expected in some areas of West Uttar Pradesh and Rajasthan. Rain and lightning are also forecasted in Jammu and Kashmir, Ladakh, Himachal Pradesh, and East Uttar Pradesh.

While the Western Disturbance influences North India, the northeast monsoon is activating in South India. According to the meteorological department, the onset of northeast monsoon rains is expected on the southern peninsula from October 15th. Along with this, heavy and very heavy rains are possible in some parts of Tamil Nadu, Puducherry, Karaikal, Kerala, and Mahé. Heavy rains are also forecasted in some places in coastal Andhra Pradesh and South Interior Karnataka. There is a risk of lightning during thunderstorms in Andhra Pradesh, Tamil Nadu, Puducherry, Karaikal, Kerala, and Mahé.

Strong winds of 40-50 kilometers per hour may also blow in these regions. Rain with gusty winds is also expected in some interior areas of Telangana and Karnataka. The northeast monsoon is particularly important for South India. Most of the rain falling in Tamil Nadu and surrounding areas after the end of the main southwest monsoon period is attributed to this monsoon. Therefore, its activation can intensify the rainy regime in southern states.

The weather impact will not be limited to North and South India only. Rain with thunderstorms and strong winds are also expected in several states of Central and Eastern India. According to the meteorological department, winds of 30-40 kilometers per hour are expected in some areas of Chhattisgarh, Odisha, Vidarbha, and West Madhya Pradesh. Light or moderate rain and lightning are possible at this time.

Short-term rain with thunderstorms is also possible in parts of Konkan, Goa, and Central Maharashtra. Coastal areas of Karnataka and Konkan-Goa may face heat and humidity causing discomfort. Weather in coastal zones may remain varied amidst rains and strong winds. Currently, the meteorological department has not issued warnings against fishermen going out to sea.