Citing an “entry error”, the India Meteorological Department (IMD) on Tuesday revised the rainfall recorded for August 6 from 56 mm to 18.7 mm, bringing down cumulative rainfall recorded at Safdarjung weather station — the base station for the Capital — for August to 197.2 mm. Until Monday, the figure was recorded as 230.5 mm on the IMD website, as per which Delhi had already crossed its August average normal rainfall in just the first eight days of the month.
However, the revised figure meant Delhi has received about 87% of its normal August rainfall so far.
As per IMD’s long period average (1991-2020), Safdarjung receives 226.8 mm of rainfall in August, leaving the city about 29.6 mm short of the monthly normal this year as of now.
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Speaking to The Indian Express, IMD Director Dr Mrutyunjay Mohapatra said the discrepancy was likely due to a human error in data logging and that the reason behind the mistake was being checked.
After an inspection on Tuesday, D R Pattanaik, Scientist G at IMD, said, “Safdarjung’s cumulative rainfall data displayed yesterday was 230.5 mm, which happened due to incorrect rainfall entry of 56 mm instead of 18.7 mm for August 6 in a table under the link.”
He added that the rainfall figure had, however, been correctly displayed in the Delhi bulletin issued daily since August 6. “The same has been corrected today and 197.2 mm is the correct figure which is being displayed currently,” he said.
IMD senior scientist Krishna Mishra said the meteorological parameters at the Safdarjung observatory are manually measured and logged. “Once an incorrect value was entered into the system, it was picked up and retained in the cumulative calculation, leading to the higher figure being displayed,” he added.
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How IMD records data
# Safdarjung is a manual meteorological observatory/station where instruments automatically transmit observations to a receiving centre.
# Observations such as precipitation, temperature, humidity, sunshine duration, wind and cloud cover are recorded manually by observers.
# Parameters, including precipitation, are first recorded. The records are sent to the designated Meteorological Centre or Regional Meteorological Centre, where they are scrutinised and manually entered into standard digital formats.
# The data then undergo offline ingestion into IMD database.
# IMD’s data management system has separate routes for recording manual and automatic observations.
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# Both eventually feed into the central database, where data processing, quality control and consistency checks are carried out before data products are generated and supplied to users.
# Errors can potentially enter at several points, including during observation, instrument measurement, transmission or data entry.
# ‘Suspect readings’ are flagged for further validation rather than being automatically discarded.
Sophiya Mathew is a Correspondent at The Indian Express, based in New Delhi. She joined the Delhi bureau in 2024, and has specialization in Integrated Multimedia Journalism from the Asian College of Journalism (ACJ), Chennai.
Professional Background
Core Beats: Her reporting is primarily focused on the Environment and Education.
Specialization: She has gained recognition for her ground-level reporting on the Yamuna floodplains and the socio-economic challenges faced by those living on its banks. She also focuses on the disparities in Delhi's education system, ranging from elite private schools to government institutions and refugee education.
Recent Notable Articles (December 2025)
Her recent work has been heavily centered on Delhi's severe winter pollution crisis and the government's regulatory responses:
1. The Air Pollution Crisis
"A tale of two cities: Delhi govt schools choke in bad air, private classrooms set up air filters" (Dec 20, 2025): A high-impact feature contrasting the "Clean Air Bubbles" in elite schools with the reality of government school students who are exposed to an equivalent of 17 cigarettes a day due to outdoor exposure.
"Delhi sees season's worst air day, second worst December AQI in nearly a decade" (Dec 15, 2025): An analytical report on the meteorological patterns trapping pollutants in the NCR.
"Delhi bans non-BS VI vehicles from outside: Why curbing vehicular pollution is key" (Dec 17, 2025): Explaining the science behind targeting specific vehicle vintages to lower particulate matter.
2. Enforcement & Regulations
"No fuel at pumps in Delhi without valid PUC certificate from December 18" (Dec 17, 2025): Breaking the news on the environment ministry's strict "No PUC, No Fuel" policy.
3. Education Policy
"Law to regulate school fee in Delhi risks becoming procedural, say parents" (Dec 13, 2025): Investigating the loopholes in the new Delhi School Education (Transparency in Fixation and Regulation of Fees) Bill, 2025.
"Monsoon Session: Private school fee regulation Bill cleared after four-hour debate" (Aug 9, 2025): Covering the legislative passage of the controversial fee hike regulation.
Signature Style
Sophiya is known for her observational depth. Her reporting often includes vivid details from school corridors, hospital waitlists, or the banks of the Yamuna to illustrate how policy failures affect the city's most vulnerable residents. She is a frequent expert guest on the 3 Things podcast, where she explains the complexities of Delhi’s environmental laws.
X (Twitter): @SophiyaMathew1 ... Read More
