June Aug 2023: District wise rainfall in in India’s SW Monsoon

In the just concluded month of Aug 2023, India received just 162.7 mm (263.8 mm in Aug 2022, 3.5% above the normal [i]) or 36.2% below normal rainfall against Aug normal rainfall of 254.9 mm as per India Meteorological department (IMD). In Aug 2021, the rainfall was 195.9 mm [ii], about 24.13% below normal and in Aug 2020, the rainfall was 327 mm [iii], or about 26.6% above normal.

June July Aug 2023 SW Monsoon rainfall across India was 629.7 mm, 10.13% below normal rainfall of 700.7 mm. June July 2023 SW Monsoon rainfall across India [iv] was 467 mm, 4.8% above normal rainfall for this period of 445.8 mm.

Even the distribution of rainfall has been far from normal in Aug 2023. June 2023 had ended with 10.1% deficit in rainfall [v] while July 2023 had ended with 13.5% surplus rainfall [vi]. June 2023 had 451 high rainfall days [vii], while July 2023 had 855 high rainfall days [viii].

Region wise rainfall graphs The first bar chart below is for the National Rainfall figure till Aug 31 2023.

The IMD divides the country into four regions. As can be seen from the following graph, the East and North East India had 16% below normal for June-Aug 2023, the three months of SW Monsoon this year so far.

The North West India ended the three months period of June Aug 2023 with just 4% surplus. In fact the cumulative seasonal rainfall in NW India has remained above normal throughout the season till Aug 31 2023.

The Central India ended the June Aug 2023 period with 10% deficit rainfall.

The South Peninsular India had the highest deficit rainfall at 17% at the end of June Aug 2023.

State wise rainfall As can be seen from IMD rainfall map for June-Aug 2023, only Chandigarh (61% excess) and Ladakh (169% excess) had large excess rainfall of above 60% surplus in this period.

Himachal Pradesh and Andaman-Nicobar had Excess (rainfall 20-59% above normal) in this three month period. 24 states had normal rainfall with rainfall between 19% deficit and 19% surplus, while eight states (Bihar, Jharkhand, Chhattisgarh, Karnataka, Kerala, Manipur, Mizoram, Lakshadweep) had deficit rainfall with rainfall 20-59% below normal in these three months. Manipur had the highest deficit at 46%. Goa had the highest rainfall at 2769.2 mm.

Sub-Division wise rainfall IMD rainfall map for sub-division wise rainfall, out of IMD’s 36 subdivisions, four (W Rajasthan, Saurashtra-Kutch, Himachal Pradesh and Andaman-Nicobar) had surplus rainfall during June Aug 2023. 20 sub divisions had normal rain, while twelve sub divisions had Deficit rainfall. The Highest deficit was 48% for Kerala. Highest surplus was 55% in Saurashtra-Kutch.

River Basin wise rainfall IMD also provides river basin wise rainfall map. As can be seen from the map, IMD has no data for two basins: Jhelum and Upper Indus). IMD also strangely reports no rainfall in Vaippar-Pamba interstate basin between Kerala and Tamil Nadu, Imphal & Others in Manipur and Tons basin. This is clearly an impossibility. It is this kind of anomalies that raise questions about accuracy of IMD’s river basin wise rainfall figures, which are actually most important for forecasting floods and reservoir inflows.

DISTRICT WISE STATE WISE RAINFALL

NORTH INDIA: Jammu & Kashmiar

Ladakh

Himachal Pradesh

Uttarakhand

Punjab

Haryana

Delhi

EAST INDIA: Uttar Pradesh

Bihar

W Bengal

Jharkhand

Odisha

Chhattisgarh

NORTH EAST INDIA: Sikkim

Assam

Arunachal Pradesh

Meghalaya

Manipur

Mizoram

Nagaland

Tripura

SOUTH INDIA: Andhra Pradesh

Telangana

Karnataka

Tamil Nadu

Kerala

WEST INDIA: Goa

Maharashtra

Madhya Pradesh

Gujarat

According to this report, Gujarat had about 37.5 mm rainfall in August 2023 (89% below normal rainfall of 225 mm), lowest in the last 86 years, since 1937 when the state had 17.4 mm rainfall. In June July 2023, state had 688 mm rainfall, the highest in last 96 years. In June July 2027, state had 750 mm rainfall. The state is likely to receive below normal rainfall in Sept 2023 too. The rainfall till Aug 31 2023 is about 18% below normal across the state. The deficit is 34% in East-Central Gujarat, 32% in N Guj and 26% in S Guj. In Saurashtra, rainfall has been 10% above normal and in Kutch, the rainfall has been 36% above normal.