Impact of Cyclonic Storms and Suggested Mitigation Actions

 

Category: Deep Depression

T.No.: T 2.0

Wind Speed: 28 33 Knots (52 61 Kmph)

 

Structures: Minor damage to loose/unsecured structures.

Road/Rail: Some breaches in kutcha road due to flooding.

Communications: Minor

Agriculture: Minor damage to banana trees and near-coastal agriculture due to salt

spray. Damage to ripe paddy crops.

Marine Interests: Very rough seas. Sea waves about 4-6 m high.

Coastal Zone: Minor damage to kutcha embankments.

Overall Damage Category: Minor

Suggested Actions: Fishermen advised not to venture into sea.

 

 

Category: Cyclonic Storm

T.No.: T 2.5-T3.0

Wind Speed: 34 47 Knots (62 87 Kmph)

 

Structures: Damage to thatched huts.

Road/Rail: Major damage to kutcha and minor damage to pucca roads.

Communications: Minor damage to power and communication lines due to breaking of

tree branches.

Agriculture: Some damage to paddy crops, banana, papaya trees and orchards.

Marine Interests: High to very high sea waves about 6 9 m high.

Coastal Zone: Sea water inundation in low lying areas after erosion of kutcha

embankments.

Overall Damage Category: Minor to Moderate

Suggested Actions: Fishermen advised not to venture into sea.

 

 

Category: Severe Cyclonic Storm

T.No.: T3.5

Wind Speed: 48 63 Knots (88 117Kmph)

 

Structures: Major damage to thatched houses/huts. Roof tops may blow off. Unattached

metal sheets may fly.

Road/Rail: Major damage to kutcha and some damage to pucca roads. Flooding of

escape routes.

Communications: Minor damage to power and communication lines.

Agriculture: Breaking of tree branches, uprooting of large avenue trees. Moderate

damage to banana and papaya trees. Large dead limbs blown from trees.

Marine Interests: Phenomenal seas with wave height 9-14 m. Movement in motor boats

unsafe.

Coastal Zone: Major damage to coastal crops. Storm surge upto 1.5m (area-specific)

causing damage to embankments/salt pans. Inundation upto 5 Km in specific

areas.

Overall Damage Category: Moderate

Suggested Actions: Fishermen advised not to venture into sea. Coastal hutment dwellers

advised to move to safer places. Other people in the affected areas to remain

indoors.

 

Category: Very Severe Cyclonic Storm

T.No.: T4.0-T4.5

Wind Speed: 64 90 Knots (118 167Kmph)

 

Structures: Total destruction of thatched houses/ extensive damage to kutcha houses.

Some damage to pucca houses. Potential threat from flying objects.

Road/Rail: Major damage to kutcha and pucca roads. Flooding of escape routes. Minor

disruption of railways, overhead power lines and signalling systems.

Communications: Bending/ uprooting of power and communication poles.

Agriculture: Widespread damage to standing crops, plantations, orchards, falling of

green coconuts and tearing of palm fronds. Blowing down of bushy trees like

mango.

Marine Interests: Phenomenal seas with wave heights more than 14m. Visibility

severely affected. Movement in motor boats and small ships unsafe.

Coastal Zone: Storm surge upto 2 m. Inundation upto 10 Km in specific areas. Small

boats, country crafts may get detached from moorings.

Overall Damage Category: Large

Suggested Actions: Fishermen not to venture into sea. Evacuation from coastal areas

needs to be mobilized. People advised to remain indoors. Judicious regulation of

rail and road traffic needed.

 

Category: Very Severe Cyclonic Storm

T.No.: T5.0-T6.0

Wind Speed: 91 119 Knots (168 221 Kmph)

 

Structures: Extensive damage to all types of kutcha houses, some damage to old badly

managed pucca structures. Potential threat from flying objects.

Road/Rail: Disruption of rail/road link at several places.

Communications: Extensive uprooting of communication and power poles.

Agriculture: Extensive damage to standing crops, plantations, orchards. Blowing down

of palm and coconut trees. Uprooting of large bushy trees.

Marine Interests: Phenomenal seas with wave heights of more than 14 m. Movement in

motor boats and small ships not advisable.

Coastal Zone: Storm surge of 2 5 m. Inundation may extend upto 10-15 Km over

specific areas. Large boats and ships may get torn from their moorings.

Overall Damage Category: Extensive

Suggested Actions: Fishermen not to venture into sea. Evacuation from coastal areas

essential. Diversion / suspension of rail traffic may be required.

 

Category: Super Cyclonic Storm

T.No.: T6.5 and above

Wind Speed: 120 Knots and above (222 Kmph and above)

 

Structures: Extensive damage to non-concrete residential and industrial buildings.

Structural damage to concrete structures. Air full of large projectiles

Road/Rail: Extensive damage to kutcha roads and some damage to poorly repaired

pucca roads. Large scale submerging of coastal roads due to flooding and sea

water inundation. Total disruption of railway and road traffic due to major

damages to bridges, signals and railway tracks. Washing away of rail/road links at

several places.

Communications: Uprooting of communication and power poles. Total disruption of

communications and power supply.

Agriculture: Total destruction of standing crops/ orchards, uprooting of large trees and

blowing away of palm and coconut crowns, stripping of tree barks.

Marine Interests: Phenomenal seas with wave heights of more than 14 m. All shipping

activity unsafe.

Coastal Zone: Extensive damage to port installations. Storm surge more than 5m.

Inundation upto 40 km in specific areas and extensive beach erosion. All ships

torn from their moorings. Flooding of escape routes.

Overall Damage Category: Catastrophic

Suggested Actions: Fishermen not to venture into sea. Large scale evacuations needed.

Total stoppage of rail and road traffic needed in vulnerable areas.