Southwest Monsoon arrived over Kerala after four days from its official onset date of June 1. However, delay in onset did not affect the performance of Monsoon.
Performance of Monsoon till first week - June 1 to June 7
First week of the month observed normal rainfall. According to the data available with Skymet, Northwest, East and Northeast India observed surplus rain during this period. While rainfall in Peninsular India was normal. Central India was the only region where rainfall was deficient by 26%. Overall the country observed normal rain during this week.
Performance of Monsoon till second week - June 8 to June 14
The second week, from June 8 to June 14 had seen an improved performance due to which the cumulative rainfall for the country from June 1 to June 14 was 61.6 mm against the average of 55.7 mm, which was 11% excess. Looking at region wise rainfall distribution, East and Northeast India recorded 20% of surplus rain during this period. Central India observed a surplus of 12%, while Peninsular India had been excess by 1%.
Performance of Monsoon till third week - June 15 to June 21
With Monsoon advancing to cover large parts of the country now, the cumulative rainfall from June 1 to June 21 stands at 112.5 mm against the normal average of 96.9 mm, which is 16% excess. Looking at the region wise distribution of rainfall, Central India has observed maximum amount of rain and is surplus by 32%. With 133 mm of rain against the average of 103 mm, Peninsular India is experiencing an excess of 30%. East and Northeast India is surplus by 3%, though the deficiency in NMMT (Nagaland, Manipur, Mizoram and Tripura) is 42%. Rainfall in Northwest India is deficient by 7%, largely due to less rain in Uttar Pradesh. However it is still considered to be normal in meteorology terms (+19% to -19% is considered normal).
About 78% of the country’s area has observed normal or excess rain till June 21. Out of the 36 sub-divisions, 14 sub-divisions recorded surplus rain, while rainfall in 12 sub-divisions has been normal.
Performance of Monsoon till fourth week - June 22 to June 28
Progressing rapidly, Southwest Monsoon covered entire India in the fourth week of June. The intensity of rain increased during this period, with all the four regions reporting surplus rainfall. The cumulative rainfall for the country from June 1 to June 28 was 176.5 mm against the normal average of 148 mm, making it 19% excess.
Looking at the region wise distribution of rainfall, Central India topped the list as it witnessed highest rainfall and is 32% excess. This was followed by Peninsular India which is surplus by 26%. With increase in rainfall over Uttar Pradesh, Northwest India recovered from deficit and is surplus by 25 %. East and Northeast India continue to be surplus by 3%, though Bihar was deficient by a margin of 24%.
Out of the 36 sub-divisions, 32 sub-divisions that account for 90% of the country’s area got surplus rainfall. While, four sub-divisions remained deficient. We expect June to end with rainfall surplus of at least 15%, which could be a record in recent past.
Performance of Monsoon till fifth week – June 29 to July 5
Subdued rainfall activity was observed across the country from June 28 to July 5. This is because the Monsoon trough had shifted close to the foothills and the rainfall was confined to some pockets only. There wasn’t any system forming in the Bay of Bengal or the Arabian Sea. Neither was there any active Western Disturbance observed during this period.
Therefore, the cumulative rainfall for the country from June 1 to July 5 was recorded at 207.8 mm against the normal average of 206.7 mm. Though, this is considered to be normal, the performance of Monsoon is poor compared to the previous week.
For instance, rainfall in Central India was surplus by 31 per cent from June 1 to June 28. But between June 1 and July 5 the surplus in the region came down to 2 per cent due to poor rains recorded in the current week. Similarly, the surplus rainfall of 25 per cent in Northwest India dropped to 5 per cent during the same period. In Peninsular India the surplus dropped to 2 per cent from 26 per cent.
The sub-division of Haryana and Delhi in Northwest India turned deficient from being normal. Punjab and Himachal Pradesh have also turned deficient. In Central India, the sub-divisions of Gujarat and Marathwada were excess but now they have turned deficient.
In Peninsular India, three sub-divisions which include Coastal Karnataka, North Interior Karnataka and Kerala have also turned deficient.
However, with good rainfall expected across the country from July 6 the deficient sub-divisions in North and East India could make some recovery.
Performance of Monsoon till sixth week – July 6 to July 12
Southwest Monsoon during the first half of the week was subdued. The countrywide rainfall between July 8 and July 9 was deficient by 4%. However, active to vigorous Monsoon conditions across the country from the second half of the week pulled down the rainfall deficiency to 1%. Peninsular India was the only region where rainfall activity was very light during this period.
The depression in the Bay of Bengal had led to good amounts of rain in almost entire East, Northeast, Northwest and Central India. Rainfall was particularly good in Northwest India, where the surplus stood at 25% from 12% the previous week.
Rainfall in the sub-division of Haryana and Delhi from being deficient the previous week became excess by 21% in the current week. Similarly Punjab from being 24% deficient turned normal. Rain sparse region like West Rajasthan saw rainfall amount become excess by 34%. East Rajasthan also observed normal rain at 17%.
It was for the first time that all the sub-divisions of Northwest India observed normal rain during this week.
Due to good rains in East India, the sub-division of Bihar from being deficient the previous week has also turned normal. Neighbouring Jharkhand too observed some very good rain and is normal at 15%. Though the overall deficiency in the region still stands at 5%.
Peninsular India was one of the few region where rainfall was scarce during this period due to which the shortfall stood at 11%.
Meanwhile, the cumulative rainfall for the country from June 1 to July 12 stands at 266.3 mm against the normal average of 270.8 mm, which is short by 2%.
Performance of Monsoon till seventh week – July 13 to July 20
Once again the first half of the week, witnessed poor Monsoon rains. The countrywide rainfall deficiency kept on mounting and rose from 3% on July 12 to 7% on July 15.
On July 12, the country was deficit by 30 mm of rain, for the month. To be precise, from July 1 to 12 the country should have received 107.2 mm of rainfall. But, it had received only 76.8 mm.
The rainfall deficiency took a big jump within next 3 days and mounted up to 48 mm. Till July 17, the country received 106.7 mm of rainfall against the normal average of 154.8 mm. The rainfall deficiency got arrested after July 17 and the next 3 days witnessed Monsoon showers across most parts of the country. However, the countrywide rainfall deficiency is still at 7% as of July 20.
The rainfall deficiency for the month of July witnessed a marginal drop only and came down from 28.4% on July 12 to 27.8% on July 20. All thanks to good Monsoon showers from the 18th of this month.
West Madhya Pradesh performed extremely well in the last one week. The cumulative rainfall figure in the region rose from a surplus of 4% on July 12 to a surplus of 23%, in span of just 8 days. Similarly, Kerala also performed relatively well.
Performance of Monsoon till eighth week – July 21 to July 27
Daily countrywide rainfall during the first two days of the week was close to normal due to which the cumulative seasonal deficiency from June 1 to July 22 stagnated at 7%. From the third day (July 23) onwards the amount and intensity of rain increased by almost 15%. This could be understood from the fact that the countrywide deficiency from June 1 to July 27 slipped to 4% compared to 7% till July 22.
Even the highest 24 hour rainfall for the country was observed on July 26. According to the data available with Skymet, the country received 14.1 mm of rain against the daily average of 9.7 mm, which is 45% excess.
Saurashtra and Kutch and Gujarat were the best performing sub-divisions this week, with record rain being observed at some places. The depression in Rajasthan was responsible for giving good to heavy rain in the region.
Till July 27 the country had received 398.2 mm of rain against the average of 415.3 mm. And about 75% of the total area consisting of 25 sub-divisions were observing normal or excess rain.
Performance of Monsoon till ninth week – July 28 to August 3
The first two days of the week started on a good note as the countrywide rainfall settled above normal. However, by the middle of the week the intensity and spread of rain reduced and continued to be light for the remaining part of the week. According to the data available with Skymet, rainfall amount during the week was marginally below normal due to which the countrywide rainfall from June 1 to July 31 ended with a deficiency of 5%.
On July 28, the country observed 13 mm of rain against the normal average of 9.9 mm, which was the highest 24 hour rainfall amount recorded during the week. The lowest amount of rainfall observed during the week was 4.3 mm against 8.9 mm, on July 31.
Gangetic West Bengal, Jharkhand and Rajasthan were the best performing pockets in the country during this week. Till August 3, rainfall amount in Gangetic West Bengal was excess by 57%. While Jharkhand was observing a surplus of 27%. West Rajasthan was the best performer as rainfall in the region was excess by a whopping 112%. East Rajasthan also observed a surplus of 29%.
On the other hand, Marathwada, Rayalaseema and North Interior Karnataka were the worst performing sub-divisions. According to the rainfall data available with Skymet, Marathwada was deficient by 58%. While North Interior Karnataka and Rayalaseema were deficient by 46% and 34%, respectively.
Currently, a well marked Monsoon system is sitting over Madhya Pradesh and adjoining Maharashtra region. In view of this system there are chances of heavy rain in Madhya Pradesh, Vidarbha, Marathwada and Madhya Maharashtra region in next 24 hours.
During this period, good showers are also expected over Rayalaseema and North Interior Karnataka. Though it will not be enough to wipe out the deficiency in the region.
From June 1 to August 3 the country received 450.3 mm of rain against the average of 481.3 mm. And about 61% of the total area consisting of 18 sub-divisions observed normal or excess rain.
Performance of Monsoon till tenth week – August 4 to August 10
Countrywide Monsoon rains were less than normal this week. There were only two occasions - August 4 and August 5 - when rains across the country were near normal due to a land depression.
Vidarbha, Marathwada, West Madhya Pradesh and West Rajasthan received some good rains during this week, while Gangetic West Bengal, Bihar, Odisha and East Uttar Pradesh observed less rains.
According to the data available with Skymet, the week started with a countrywide rainfall deficiency of 6%, which mounted to 9% by the end of the week (August 10). And out of the four regions of Northwest India, East and Northeast India, Central India and Peninsular India, Northwest India was the only region to observe a surplus of 2% (From June 1 to August 10). The remaining regions observed less rain, with Peninsular India being the most deficient at 22%.
However, the sub-divisions like Vidarbha, Marathwada, Madhya Maharashtra, Rayalaseema and Telangana, which were parched for some time observed good rain during this week.
From June 1 to August 10 the country received 495.1 mm of rain against the average of 544.4 mm, which is 9% deficient. About 64% of the total area consisting of 20 sub-divisions observed normal or excess rain.
Performance of Monsoon till eleventh week – August 11 to August 17
The overall performance of Southwest Monsoon was satisfactory this week. Though the countrywide rainfall deficiency increased marginally, good rains in the last 2-3 days helped in containing the deficiency. According to the data available with Skymet the week started with countrywide rainfall deficiency of 9.3%, which touched 9.9% on August 15. However, good spells of rain in Peninsular India and East India, particularly along the foothills and Sub Himalayan West Bengal in the last couple of days helped in containing the deficiency, which stands at 9.6%. (June 1 to August 17)
Few pockets in Uttar Pradesh, Bihar, Sikkim and Sub Himalayan West Bengal observed good rain. Peninsular India which had not observed much rain last week also observed some rain, particularly Tamil Nadu and South Interior Karnataka. On few days Tamil Nadu witnessed more than triple the daily rainfall.
From June 1 to August 17 the country received 548.6 mm of rain against the average of 606.8 mm. About 65% of the total area consisting of 21 sub-divisions observed normal or excess rain.
Performance of Monsoon till twelfth week – August 18 to August 24
The countrywide rainfall deficiency which was rising and had touched 10% during the end of the previous week ( August 11 to August 17) saw a marginal improvement and settled at 9 % during the first half of the new week. However, the deficiency did not get arrested and by August 24 - end of the new week - the deficiency rose to 10.6%. The last two days have particularly been very poor in terms of rainfall amounts across the country.
The best performing sub-divisions this week were Bihar and Rayalaseema. According to the data available with Skymet, rainfall in Bihar was deficient by 36% last week, which improved to settle at -15% by August 24. Similarly Rayalaseema saw the deficiency slide to 6% from 12% the previous week.
While Central India, which had been observing some very good rain and was most of the time surplus saw the rainfall deficiency increase from 9% to 14 % this week.
From June 1 to August 24 the country received 593.1 mm of rain against the average of 663.5 mm, which is 10.6% deficient. About 71% of the total area consisting of 23 sub-divisions observed normal or excess rain.
Performance of Monsoon till thirteenth week – August 25 to August 31
The first two days of the week (August 25 and August 26) were not good for the country in terms of rainfall. According to the data available with Skymet, 3.1 mm of cumulative rainfall was observed in the country on August 25 against the normal of 7.4 mm. On August 26, the country received 3.2 mm of rain against the average of 7.2 mm. Thereafter, rainfall amounts increased to over 6 mm a day, but they were still short of the daily average of over 7 mm.
The last two days of the week saw fairly good amounts of rain. For instance, the countrywide rainfall on August 30 was 7.4 mm against the average of 7.1 mm. While 7 mm of rain was recorded on August 31 against the daily normal of 6.7 mm.
Good amounts of rain during the last days of the week pulled down the countrywide rainfall deficiency to 11% on August 31, from 12% a few days back.
Most of the contribution in rainfall amounts this week has come from East and Northeast India, particularly Assam and Meghalaya, Arunachal Pradesh, Sikkim and Sub Himalayan West Bengal. These pockets have received heavy to very heavy rains. Some places have recorded four times their average rainfall. This has in fact created flood like situation in many parts of Northeast India.
The country from June 1 to August 31 received 632.2 mm of rain against the normal average of 714.1 mm, which is 11% deficient. About 64% of the total area consisting of 21 sub-divisions observed normal or excess rain.
Performance of Monsoon till fourteenth week – September 1 to September 7
September is the withdrawal period for Southwest Monsoon which is why the average daily and monthly rainfall decreases across the country. Dail rainfall in the peak months of July and August is 8 mm dropping to 7 mm by first week of September. And as we reach the end of the month the average drops to 5 mm.
In the last one week the country has observed subdued rainfall activity. While Monsoon showed signs of withdrawal from West Rajasthan, Northeast India was one of the regions that observed good rain along with Peninsular India.
Due to poor rains this week the countrywide rainfall deficiency on September 7 had risen to 14% from 11% last week. The good thing that happened this week is that Peninsular India, which was one of the most deficient pockets observed some good rain.
Karnataka, Andhra Pradesh and Tamil Nadu received 5 to 7 times the daily average rainfall. The cumulative deficiency of Peninsular India came down to 19% from 21% last week.
However, the other three regions saw rainfall deficiency rise. For instance, East and Northeast India from being 2% deficient last week is deficient by 3% now. Similarly, Northwest India is 15% deficient from 10% last week. And Central India has seen rainfall deficiency climb to 19% from 15%.
According to the data available with Skymet, the country from June 1 to September 7 received 655.4 mm of rain against the normal average of 762.3 mm, which is 14% deficient. About 61% of the total area consisting of 19 sub-divisions observed normal or excess rain.
Performance of Monsoon till fifteenth week – September 8 to September 14
Southwest Monsoon was vigorous over Peninsular India during last one week. But, intensity of rainfall reduced significantly over the northeastern states. Saurashtra received some rain in the fag end of the week. This came as a much needed respite for the people of Gujarat, as the state remained dry for quite some time. Northern plains were mostly hot and dry.
The country as a whole received minimal rains on a daily basis. The country received lowest rainfall (2.5 mm) for the week on September 12, against the daily average rainfall of 6 mm.
Overall, the country recorded 677.4 mm of rainfall, against the normal average of 808.1 mm during the week. Consequently, the cumulative rainfall deficiency for the country rose from 14% to 16% by the end of the week.
Monsoon rains were mostly confined to the Southern Peninsula. In fact, good showers were witnessed even in the most rain deficit pockets. Rainfall deficiency reduced from 28% to 25% within a week in North Interior Karnataka. Deficiency reduced in Marathwada by 5% and settled at 44%. Madhya Maharashtra also witnessed a significant drop in Monsoon rainfall deficiency. Coastal Andhra Pradesh witnessed good showers. As on September 12, the subdivision recorded 17% more rains than the normal average.
Rest of the country witnessed subdued Monsoon activity. In the subdivision of Northwest India, rainfall deficiency increased from 16% to 20% in last one week. Similarly, East and Northeast India saw the rainfall deficiency figure rise from 4% to 7%. The total subdivisions having normal and excess Monsoon rains have reduced to 56%.
At present, only one subdivision (West Rajasthan) has managed to receive excess rains. Normal Monsoon rains have been recorded in 18 subdivisions, while 17 of them remained deficit.
Performance of Monsoon till sixteenth week – September 14 to September 21
Two weather systems, one which turned into a depression while over Gujarat and the second which remained as a low pressure area, gave some good amounts of rain across the country this week. In fact it is one of the rainiest week of the season. According to the data available with Skymet, the countrywide rainfall on September 21 was recorded at 10.2 mm against the daily average of 4.7 mm. The last time the 24 hour countrywide rainfall exceeded the daily average was on August 5.
This spell of rain has pulled down the countrywide rainfall deficiency to 14 percent at the moment from 16 percent. In some pockets the deficiency has decreased by almost 8%. For instance, the rainfall amount in Saurashtra and Kutch is surplus by 7%. Till a few days back the region was staring at a deficiency of 5%. The deficiency in Marathwada has come down to 35% from 43% earlier.
The best performing pocket this week was Central India, particularly the sub-divisions of Vidarbha, Marathwada and Gujarat.
Good rains this week have pushed up the total area receiving normal or excess rains in the country to 64% from 61% last week. The total amount of rain received in the season so far is 728.6 mm against the normal of 843.7 mm, which is 14% deficient.
Performance of Monsoon till sixteenth week – September 22 to September 28
Unlike the previous week, which was one of the rainiest of the season, the current week has turned out to be poor in terms of rain across the country. The average daily rainfall has been a little below the average of 5.1 mm. In fact the lowest daily rainfall of the season (0.8 mm) was recorded this week, on September 27.
Only during the first two days of the week good rainfall was observed across the country. The deficiency during this period had dropped to 12%, but poor rains thereafter pushed up the deficiency to 14% by the end of the week.
Rainfall during the first half of the week was largely confined to Northeast and Northwest India. But in the second half, rainfall was confined to Peninsular India. The remaining parts of the country observed almost dry conditions, which led to rise in countrywide rainfall deficiency.
According to the data available with Skymet, the country from June 1 to September 28 received 758.6.4 mm of rain against the normal average of 879.6 mm, which is 14% deficient. About 61% of the total area consisting of 19 sub-divisions observed normal or excess rain.
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