Special Report| ISRO's Warning For Odisha, AP, WB: 2026 Oct-Nov Cyclones to Pack Double the Punch; Another 1999 Super Cyclone in Making?

Bhubaneswar: Isro has dropped a bombshell recently.  The country's apex space body predicted a big churning at ocean level during the period of January to August this year. And noting down the intensive churnings, Isro has issued a big warning to all coastal states and disaster mitigating agencies. 

The bold prediction and big warning by ISRO has been that North Indian Ocean (Arabian Sea and Bay of Bengal) will be churning 3 cylones only, but their intensities will be nearly double. This 'doubling intensity' cyclones hitting the North Indian Ocean has raised the heckles across all stakeholders – from Govts, Disaster Mitigating Agencies to Weather watchers. 

If the latest mathematical modelling from the Indian Space Research Organisation (ISRO) holds through the coming post-monsoon season, the concern for the east coast may not be the number of cyclones but the intensity packed into a relatively small number of systems.

The BIG Daddy Warning

ISRO’s seasonal prediction for the October-December 2026 period points to three tropical cyclones over the North Indian Ocean, broadly around the historical seasonal range. But the striking signal is the projected Power Dissipation Index (PDI) of about 13.06 million knots³, against a historical mean of 7.15 million knots³ – an increase of roughly 82%.

For Odisha, north Andhra Pradesh and West Bengal, that distinction matters.

The ISRO forecast is for the entire North Indian Ocean –the Bay of Bengal and Arabian Sea –and does not specify that two cyclones will necessarily hit these three states. But the historical October-November climatology of the northern Bay of Bengal makes the Odisha–north Andhra–West Bengal coastline one of the regions that needs particular attention if the forecast signal materialises.

North Indian Ocean Tropical Cyclone Frequency & 2026 Forecast

Year	Total Cyclones Formed (NIO)	Bay of Bengal (BoB)	Arabian Sea (AS)	Key Metrics / Notes
1985	6	4	2	—
1986	3	2	1	—
1987	5	4	1	—
1988	4	3	1	—
1989	3	2	1	—
1990	4	3	1	—
1991	4	3	1	—
1992	7	5	2	High activity season
1993	4	2	2	—
1994	4	3	1	—
1995	4	3	1	—
1996	6	5	1	—
1997	4	3	1	—
1998	6	3	3	Balanced basin distribution
1999	4	3	1	—
2000	5	4	1	—
2001	4	2	2	—
2002	4	3	1	—
2003	3	2	1	—
2004	4	3	1	—
2005	4	3	1	—
2006	3	3	0	Zero AS development
2007	6	4	2	—
2008	4	3	1	—
2009	4	3	1	—
2010	5	4	1	—
2011	2	1	1	Basin minimum
2012	2	2	0	Basin minimum
2013	5	5	0	BoB dominance
2014	3	2	1	—
2015	4	4	0	—
2016	4	4	0	Normal baseline mirror
2017	3	2	1	—
2018	7	4	3	High activity season
2019	8	3	5	Record Arabian Sea Year
2020	5	3	2	—
2021	5	3	2	—
2022	3	3	0	—
2023	6	4	2	—
2024	5	3	2	—
2025	4	2	2	—
2026 (ISRO Forecast)	3 (Post-Monsoon)	—	—	PDI: ~13.06 × 10⁶ knots³ (~83% above average destructiveness)

Basin Summary & Dynamics

• Historical Baseline: The NIO basin averages 4 to 5 tropical cyclones annually, maintaining an approximate 4:1 Bay of Bengal to Arabian Sea dominance ratio.
• The 2026 Anomaly: While a 3-storm post-monsoon count aligns with normal baseline frequencies (similar to 2013 or 2016), the projected Power Dissipation Index (PDI) of ~13.06 $\times$ 10⁶ knots³ indicates that cumulative storm energy will run nearly double historical destructiveness norms. 
• The numbers do not support a claim that 2026 will necessarily produce an unusually large number of cyclones. In fact, ISRO's projected three systems are within the broad historical range.

What changes is the destructiveness parameter.

Indicator

Historical signal

ISRO 2026 projection

What it means

Post-monsoon cyclone frequency

Around 2–3 in the cited climatological baseline

3

Frequency is not exceptional

PDI

7.15 × 10⁶ knots³

13.06 × 10⁶ knots³

About 82% above mean

Key period

October–December

October–December 2026

Peak risk overlaps with the east-coast cyclone season

Primary basin of concern for this story

North Indian Ocean

Bay of Bengal focus

Odisha, north Andhra and West Bengal remain exposed

Main risk indicated by PDI

Frequency + intensity + duration

Higher destructive potential

A few storms could account for disproportionately high impact

What ISRO Warning Means for Odisha? 

Odisha's cyclone history provides a useful benchmark for understanding why intensity matters more than storm count.

The 1999 Odisha Super Cyclone and Cyclone Phailin in 2013 demonstrated how a relatively small number of exceptionally intense systems can dominate the disaster record.

Cyclone	Year	Month	Main affected/landfall zone	Approx peak/landfall intensity*	Rainfall/impact significance
Odisha Super Cyclone	1999	October	Odisha coast, Ersama region	~260 km/h	Catastrophic rainfall (300mm), storm surge and coastal destruction
Phailin	2013	October	Gopalpur, Odisha	~215 km/h	Extremely heavy rainfall and widespread flooding
Hudhud	2014	October	Visakhapatnam	~185 km/h	Torrential rainfall and major urban/agricultural impacts
Titli	2018	October	South Odisha–north Andhra sector	~150 km/h	Very heavy rain and landslide risk
Bulbul	2019	November	West Bengal–Sundarbans	~110–120 km/h	Heavy rain and coastal flooding
Dana	2024	October	Odisha coast	~110 km/h	Heavy to extremely heavy rainfall over Odisha and adjoining Bengal
2026 projection	2026	Oct–Dec	Not specified by ISRO	Potentially ~180–240+ km/h (Based on massive PDI deviation)	Extremely Severe & Extended Duration (Risk of prolonged torrential rain and severe storm surges).

*Intensity figures are approximate historical values and should not be treated as directly comparable across different agencies' measurement conventions.

The post-2019 pattern: the intensity has been quieter

The historical data analysed also highlights a noticeable reduction in the intensity of several October-November systems affecting the three-state corridor after the powerful 2018–19 period.

Period	Notable systems affecting the broader Odisha–north Andhra–West Bengal corridor	Broad intensity pattern
1999–2014	Odisha Super Cyclone, Phailin, Hudhud	Several exceptionally powerful systems
2015–2018	Titli and other systems	Mixed, including a major October cyclone
2019	Bulbul	Lower intensity than the major Odisha benchmark cyclones
2020–2023	Multiple Bay systems, including weaker late-season systems	Predominantly lower-intensity landfall/impact events in the three-state corridor
2024	Dana	Moderate-intensity cyclone with significant rainfall impact
2025	Montha	Moderate-intensity system affecting the north Andhra–south Odisha sector
2026	ISRO seasonal signal	Potential reversal in destructive potential

This is where the 2026 forecast becomes interesting.

The signal is not that the region has suddenly entered a permanently super-cyclonic regime. Rather, after several years in which the most damaging October-November systems affecting this corridor were generally less intense than the 1999/2013 benchmarks, ISRO's model is detecting an environment in which destructive potential could rise sharply.

But why can El Niño coexist with a high-intensity cyclone signal?

At first glance, this appears contradictory.

A strong El Niño is generally associated with atmospheric changes that can make tropical cyclone development over the North Indian Ocean less favourable. Yet the WMO 2026 assessment points towards an unusual combination of strong El Niño conditions in the Pacific and a positive Indian Ocean Dipole signal over the Indian Ocean.

The important point is that the Pacific and Indian Ocean do not operate as isolated systems.

Climate driver	Expected 2026 role	Possible cyclone implication
Strong El Niño	Changes large-scale Walker circulation and atmospheric circulation	Can suppress overall cyclone formation through less favourable atmospheric conditions
Positive IOD	Alters Indian Ocean SST and circulation	Can create a more favourable regional thermal environment
High ocean heat content	Provides greater energy to developing systems	Supports intensification if atmospheric conditions become favourable
MJO/Equatorial waves	Provide subseasonal pulses of convection and vorticity	Can create short windows favourable for cyclogenesis
Vertical wind shear	Determines whether a developing storm can organise vertically	Low shear favours intensification; high shear suppresses it
Steering currents	Determine track and landfall region	Controls whether a Bay system approaches Odisha, north Andhra, Bengal or moves elsewhere

That produces the possibility of a low-frequency/high-impact seasonal structure: not necessarily many storms, but a smaller number of systems with greater potential to intensify.

ISRO's mathematical approach is the important part

The forecast is based on the idea that the atmosphere and ocean carry a form of seasonal memory.

The ISRO assessmnet has used 40 years of ERA5 global reanalysis data, examining environmental predictors from January through August before forecasting the post-monsoon season.

Component	What is being assessed	Why it matters
Sea-surface temperature	Warmth of the tropical ocean	Warm water supplies latent heat to cyclones
Ocean heat content	Heat stored below the surface	Reduces the chance of rapid weakening from upwelling
Atmospheric circulation	Large-scale circulation anomalies	Determines whether disturbances can organise
Vertical wind shear	Difference between lower and upper-level winds	Strong shear can disrupt cyclone structure
Convective activity	Organisation of tropical thunderstorms	Provides the initial energy and circulation for cyclogenesis
Historical reanalysis	40-year ERA5 record	Establishes statistical relationships between pre-season conditions and later cyclone behaviour
Forecast verification cited in the inputs	r ≈ 0.92 for frequency; r ≈ 0.93 for PDI	Indicates a strong historical statistical relationship in the model

Those correlation values are important, but they do not mean the forecast has 92–93% certainty of a particular cyclone hitting Odisha. A seasonal statistical correlation and a specific landfall forecast are two different things.

Where the 300-mm rainfall question comes in

For Odisha, north Andhra and West Bengal, the rainfall risk may actually be more geographically extensive than the wind risk.

A cyclone does not need to make a direct landfall over a district to produce damaging rainfall. A large circulation can draw enormous quantities of moisture from the Bay of Bengal and push rain bands hundreds of kilometres inland.

Therefore, if a 2026 system becomes unusually intense and remains organised for a prolonged period, rainfall totals in the 200–300 mm-plus range over favourable locations are physically plausible, particularly where the cyclone interacts with moisture convergence, coastal convergence and terrain.

But this is a scenario, not an ISRO district-level rainfall forecast.

Possible hazard	Odisha	North Andhra Pradesh	West Bengal
Extreme coastal wind	Very high exposure	Very high exposure	High exposure in coastal districts
Storm surge	Major concern along vulnerable coast	Major concern	Major concern, particularly low-lying coastal areas
200–300 mm+ rainfall	Possible in strong/slow-moving systems	Possible, especially near landfall and terrain	Possible, particularly in coastal/southern districts
Inland flooding	Rivers, drainage and urban areas	Coastal plains and river basins	Low-lying deltaic areas and urban drainage
Landslides	Mainly hilly/southern districts	Stronger concern in hilly terrain	More limited geographically
Agricultural damage	Very high	Very high	Very high
Risk window	October–November	October–November	October–November

Could there be two major cyclones between October and November?

It is possible, but the ISRO forecast supplied here does not specifically say that two cyclones will hit Odisha, West Bengal or north Andhra Pradesh.

That distinction is essential.

ISRO's three-cyclone prediction applies to the North Indian Ocean basin and the October-December season. The forecast does not provide a deterministic sequence saying, for example, that one cyclone will hit Odisha in October and another West Bengal in November.

However, if the predicted three-system season develops with an unusually high PDI, the historical climatology means that multiple systems affecting the northern Bay during October-November cannot be dismissed.

The more defensible interpretation is therefore:

2026 may produce fewer cyclones than the most active years, but the cyclones that do develop could have a substantially greater destructive footprint.

The northern Bay is the story's geographic focus

Although ISRO's forecast covers the whole North Indian Ocean, the Odisha–north Andhra–West Bengal corridor deserves separate attention because of its historical exposure.

The geography also changes through the season.

Season phase	Broad cyclone tendency	East-coast implication
Early October	Bay of Bengal becomes increasingly active	Odisha and north Andhra can become vulnerable
Mid/late October	Northern and central Bay remain important	Odisha and Bengal coast require close monitoring
November	Cyclone activity continues, with tracks influenced by changing steering flow	West Bengal and Odisha remain exposed, while southward tracks can also emerge
December	Cyclone tracks increasingly favour southern parts of the Bay in many setups	Risk shifts progressively towards Andhra/Tamil Nadu/Sri Lanka sectors

This is why a basin-wide ISRO forecast should not be translated into a state-specific landfall prediction months in advance.

The 2026 message for Odisha, north Andhra and West Bengal

The most responsible reading of ISRO's forecast is neither “two super cyclones are coming” nor “El Niño will suppress everything.”

It is more nuanced.

The mathematical forecast points towards three post-monsoon cyclones over the North Indian Ocean, broadly normal in number but potentially much higher in aggregate destructive potential. The cited PDI of 13.06 million knots³ against a 7.15 million historical mean is the central signal.

For the east coast, that raises the possibility that one or more systems could become much stronger or longer-lived than the recent October-November pattern has accustomed coastal communities to.

And if such a system tracks towards Odisha, north Andhra or West Bengal, the hazard would not be limited to wind. Storm surge, coastal inundation, prolonged rainfall, 200–300 mm-plus rainfall pockets, river flooding and agricultural losses could become the larger story.

The comparison with 1999 and 2013 therefore has to be used carefully. Those cyclones are historical benchmarks for what extreme intensity can do; they are not forecasts for 2026.

The real question for the coming season is whether the high PDI signal detected by ISRO becomes visible in the atmosphere when the first October disturbances begin to form.

Bottomline: 2026 post Monsoon story, scripted by ISRO, zooms on potentially an “extremely severe to super cyclone” show. For Odisha, north Andhra Pradesh and West Bengal, that difference could become critical if the seasonal signal survives into the October-November cyclone window.