Why in News: The India Meteorological Department (IMD) issued a yellow heatwave alert for Delhi-NCR on May 19, 2026, with maximum temperatures recorded at 43–45°C across the capital region. IMD simultaneously issued an orange alert (severe heatwave) for Wardha and Yavatmal districts of Vidarbha, Maharashtra. The northwest India plains, including Rajasthan, UP, Haryana, and Punjab, are forecast to remain under heatwave to severe heatwave conditions until May 24. IMD also confirmed that the Southwest Monsoon onset over Kerala remains on track for May 26, 2026: five days ahead of the normal date of June 1.
Delhi Heatwave: May 19, 2026
| Parameter | Data |
|---|---|
| Maximum temperature (Delhi) | 43–45°C (recorded May 19) |
| Normal maximum for May 19 | ~40°C |
| Departure from normal | +3 to +5°C |
| IMD alert level | Yellow (heatwave, temperature ≥40°C; 4.5°C above normal) |
| Duration forecast | Until May 24, 2026 |
| Relative humidity | 10–20% (very dry; typical pre-monsoon conditions) |
| Hottest station | Barmer, Rajasthan (~48°C) |
Heatwave Classification (IMD Standards)
| Category | Plain stations (below 1,000m) | Coastal stations | Hills (above 1,000m) |
|---|---|---|---|
| Heatwave | Max temp ≥40°C AND ≥4.5°C above normal | Max temp ≥37°C AND ≥4.5°C above normal | Max temp ≥30°C AND ≥4.5°C above normal |
| Severe heatwave | Max temp ≥40°C AND ≥6.5°C above normal | Max temp ≥37°C AND ≥6.5°C above normal | Max temp ≥30°C AND ≥6.5°C above normal |
| Extreme heatwave | Max temp ≥45°C | Max temp ≥41°C | — |
Delhi’s 43–45°C with 3–5°C above normal qualifies as a heatwave (yellow alert). Barmer’s ~48°C qualifies as an extreme heatwave.
Vidarbha Orange Alert: Maharashtra
| District | Alert Level | Details |
|---|---|---|
| Wardha | Orange (severe heatwave) | Max 44–46°C; 6.5°C above normal |
| Yavatmal | Orange (severe heatwave) | Max 44–46°C; 6.5°C above normal |
| Nagpur | Yellow | Max 42–43°C |
| Akola | Yellow | Max 43–44°C |
Vidarbha is Maharashtra’s most heat-prone inland region, cotton-growing belt, low tree cover, and proximity to the Deccan Plateau’s hot air mass make it vulnerable to extreme pre-monsoon heat.
IMD Alert Colour Code
| Colour | Meaning | Action |
|---|---|---|
| Green | No warning | Watch |
| Yellow | Be Aware, heatwave | Watch and prepare |
| Orange | Be Prepared, severe heatwave | Alert; action likely needed |
| Red | Take Action, extreme heatwave | Immediate action required |
Southwest Monsoon: 2026 Outlook
Onset Forecast: Kerala May 26
IMD’s forecast for Southwest Monsoon onset over Kerala: May 26, 2026: five days earlier than the normal date of June 1.
| Parameter | 2026 Status |
|---|---|
| SW Monsoon onset Kerala | May 26 (normal: June 1; 5 days early) |
| Seasonal rainfall (June–September) | 92% of Long Period Average (LPA): classified as Below Normal |
| LPA (1971–2020 baseline) | ~868.6 mm for the country as a whole |
| Below Normal definition | 90–95% of LPA |
| El Niño probability (June–August) | High (NOAA ~62%; PAGASA ~79%), a key factor suppressing rainfall |
Why Early Onset?
- The Mascarene High (pressure system over Indian Ocean) has strengthened earlier than normal, pumping moisture northward
- Arabian Sea branch of the monsoon is building strength; Bay of Bengal branch on schedule
- However, despite early onset, total seasonal rainfall is forecast at 92% LPA, early does not mean bountiful
El Niño Impact
El Niño (warm SST anomaly in central-eastern equatorial Pacific) is associated with below-normal monsoon rainfall in India:
| El Niño Phase | Effect on India Monsoon |
|---|---|
| El Niño active | Below Normal to Deficient rainfall (historically) |
| La Niña active | Above Normal to Normal rainfall |
| ENSO Neutral | Normal rainfall |
El Niño probability for June–August 2026 is high (NOAA: ~62%; PAGASA: ~79%), which explains the 92% LPA forecast. Notable below-normal monsoon years linked to El Niño: 1987, 2002, 2009, 2014.
IMD Alert System and Heat Action Plans
National Disaster Management Authority (NDMA) Guidelines
- Heat Action Plans (HAPs): All states/UTs mandated to have HAPs; district-level coordination
- National Heat Portal: Real-time heat health alert system
- Vulnerable populations: outdoor workers, elderly, infants, people with chronic illness
- NIMHANS + ICMR coordination for heat-health surveillance
- Ahmedabad HAP (est. 2013): India’s pioneering city-level HAP; model for other cities; run by IIPH (Indian Institute of Public Health, Gandhinagar) in partnership with AMC (Ahmedabad Municipal Corporation)
IMD Forecast Services
| Service | Detail |
|---|---|
| National Weather Forecasting Centre (NWFC) | 24×7 operational centre; Delhi; issues national forecasts |
| Extended Range Forecast (ERF) | 3–4 week outlook; issued weekly |
| Seasonal Forecast | April–June issued in April; June–September issued in April and updated in May |
| District-level forecasts | 5-day district-wise weather forecasts for all 700+ districts |
| Agri-Met services | Weekly agro-meteorological bulletins for farmers (in collaboration with IMD and ICAR) |
Northeast India: Contrasting Conditions
While northwest India burns, Northeast India is seeing the opposite extreme on May 19:
- Assam, Meghalaya, Arunachal Pradesh: Heavy to very heavy rainfall + thunderstorms forecast
- Brahmaputra flood season: Pre-monsoon rains causing early flash floods in Assam’s flood plains
- Cyclone risk: Bay of Bengal heating up, IMD monitoring for potential pre-monsoon cyclone development
Urban Heat Island Effect: Delhi-NCR
Delhi’s temperatures are exacerbated by the Urban Heat Island (UHI) effect:
- Concrete, asphalt, and reduced green cover trap solar radiation
- Delhi’s green cover is ~20% of city area, below the 33% norm for Indian cities
- Air conditioning units release waste heat, creating a feedback loop
- UHI can add 2–5°C to city temperatures relative to surrounding rural areas
Delhi Heat Action Plan (DHAP): Delhi has a Heat Action Plan but its implementation has been criticised as inadequate, cooling centres are limited, worker protections weak.
UPSC Relevance
GS Paper 3: Disaster Management / Environment
- Heatwave classification: IMD’s criteria for heatwave, severe heatwave, extreme heatwave; colour-coded alert system
- Monsoon: SW monsoon onset; LPA; El Niño–monsoon linkage; below-normal classification
- Urban Heat Island effect: causes, consequences, mitigation
- Heat Action Plans: NDMA guidelines; Ahmedabad model; cooling centres
GS Paper 1: Geography
- SW monsoon: onset, withdrawal, progress across India; role of Mascarene High, Arabian Sea branch, Bay of Bengal branch
- Vidarbha: geographic characteristics; heat vulnerability
Keywords: IMD, yellow alert, heatwave, Delhi-NCR, Vidarbha, orange alert, SW Monsoon onset, Kerala, LPA, Below Normal, El Niño, Mascarene High, Urban Heat Island, Heat Action Plan, NDMA.
Sources: Business Standard, IMD, PIB
📌 Facts Corner: Knowledgepedia
Heatwave: Delhi-NCR (May 19, 2026):
- Max temperature: 43–45°C (3–5°C above normal)
- IMD alert: Yellow (heatwave)
- Hottest in India: Barmer, Rajasthan (~48°C; extreme heatwave)
- Maharashtra: Orange alert for Wardha and Yavatmal (Vidarbha), severe heatwave
IMD Heatwave Classification:
- Heatwave: Max temp ≥40°C AND ≥4.5°C above normal (plain stations)
- Severe heatwave: Max temp ≥40°C AND ≥6.5°C above normal
- Extreme heatwave: Max temp ≥45°C
IMD Alert Colours:
- Green = watch | Yellow = be aware | Orange = be prepared | Red = take action
SW Monsoon 2026:
- Onset over Kerala: May 26, 2026 (normal: June 1; 5 days early)
- Seasonal forecast: 92% of LPA = Below Normal rainfall
- LPA (1971–2020): ~868.6 mm (India average, June–September)
- Below Normal definition: 90–95% of LPA
- El Niño probability (Jun–Aug 2026): High, NOAA ~62%; PAGASA ~79%, primary suppressor of rainfall
IMD: Key Facts:
- Under: Ministry of Earth Sciences
- HQ: New Delhi (Mausam Bhawan)
- Established: 1875
- National Weather Forecasting Centre (NWFC): 24×7 operational centre
Ahmedabad Heat Action Plan:
- India’s first and model city-level HAP; established 2013
- Partners: AMC (Ahmedabad Municipal Corporation) + IIPH Gandhinagar (Indian Institute of Public Health)
- Serves as the national template for city-level heat response
Urban Heat Island (UHI):
- Effect: Cities are 2–5°C hotter than surrounding rural areas
- Causes: concrete/asphalt surfaces, waste heat from AC, reduced green cover
- Delhi’s green cover: ~20% (below 33% norm)
Source: IMD Yellow Alert for Delhi-NCR: 43–45°C Heatwave; SW Monsoon Onset on Track for Kerala May 26 — Ujiyari.com | Free UPSC & State PCS Current Affairs
