This is storm ALVIN:BERTIE that was active in 2006 in the S. Indian region with maximum winds of 213 km/h.

What was the maximum intensity of the storm?

Max Wind: 213 km/h. Min Pressure: hPa.

storm ALVIN:BERTIE (2006) - Track and intensity details

Name: storm ALVIN:BERTIE
Start: 2005-11-18
End: 2005-12-03
Location: S. Indian

ALVIN:BERTIE (2006)

Storm Code: 2005322S04095 | Region: S. Indian
Active from 18/11/2005 to 03/12/2005 (15 days)

213 km/h

1-min Wind (JTWC)

Level 17

185 km/h

10-min Wind (BOM)

Level 16

927 hPa

Min Pressure

4,195 km

Distance

Forecast Agencies

Agency	Max Intensity	Trajectory	Energy	highest_classification
WMO (International)	185	928	61	4,138	52.20	80.86	Level 16 - Super Typhoon
JTWC	213	927	89	2,633	62.56	104.94	Level 17 - Super Typhoon
Météo-France	185	930	121	4,195	51.41	77.88	Level 16 - Super Typhoon
BOM (Australia)	185	928	47	1,349	39.07	61.87	Level 16 - Super Typhoon
NEUMANN	213	~	89	2,633	62.56	104.94	Level 17 - Super Typhoon

Agency

Max Intensity

Trajectory

Energy

highest_classification

Max Wind (km/h)

Min Pressure (hPa)

Number of points

Distance (km)

ACE (10⁴ (km/h)²)

PDI (10⁶ (km/h)³)

WMO (International)

185

928

4,138

52.20

80.86

Level 16 - Super Typhoon

JTWC

213

927

2,633

62.56

104.94

Level 17 - Super Typhoon

Météo-France

185

930

121

4,195

51.41

77.88

Level 16 - Super Typhoon

BOM (Australia)

185

928

1,349

39.07

61.87

Level 16 - Super Typhoon

NEUMANN

213

2,633

62.56

104.94

Level 17 - Super Typhoon

Advanced Meteorological Indices by Agency Automatically calculated from raw data

WMO (International) RI

Energy
ACE (10⁴ (km/h)²)	52.20	Very High
PDI (10⁶ (km/h)³)	80.86
Intensification / Weakening
Max Wind Gain/Step	+28 km/h
Max Wind Gain/24h	+56 km/h	RI
Max Wind Loss/Step	-37 km/h
Pressure Variation
Max Pressure Drop/Step	-20 hPa
Max Pressure Drop/24h	-38 hPa	RI
Max Pressure Rise/Step (weakening)	+20 hPa
Movement & Duration
Avg Movement Speed	11.5 km/h
Tracking Time	360h (15 days)
Time as TD+ (≥34kt)	174h (7.3d)
Time as Storm+ (≥64kt)	96h (4d)
Peak Intensity & Range
Peak Intensity	19:00 22/11/2005 -11.9°N, 90.5°E
Latitude	-14.7°N – -3.8°N (10.9°)
Longitude	68.1°E – 95.1°E (27°)

JTWC RI

Energy
ACE (10⁴ (km/h)²)	62.56	Very High
PDI (10⁶ (km/h)³)	104.94
Intensification / Weakening
Max Wind Gain/Step	+15 km/h
Max Wind Gain/24h	+65 km/h	RI
Max Wind Loss/Step	-24 km/h
Pressure Variation
Max Pressure Drop/Step	-8 hPa
Max Pressure Drop/24h	-36 hPa	RI
Max Pressure Rise/Step (weakening)	+11 hPa
Movement & Duration
Avg Movement Speed	10 km/h
Tracking Time	264h (11 days)
Time as TD+ (≥34kt)	174h (7.3d)
Time as Storm+ (≥64kt)	111h (4.6d)
Peak Intensity & Range
Peak Intensity	07:00 23/11/2005 -12.5°N, 90.3°E
Latitude	-14.8°N – -3.7°N (11.1°)
Longitude	80.3°E – 95.1°E (14.8°)

Météo-France RI

Energy
ACE (10⁴ (km/h)²)	51.41	High
PDI (10⁶ (km/h)³)	77.88
Intensification / Weakening
Max Wind Gain/Step	+9 km/h
Max Wind Gain/24h	+65 km/h	RI
Max Wind Loss/Step	-19 km/h
Pressure Variation
Max Pressure Drop/Step	-7 hPa
Max Pressure Drop/24h	-40 hPa	RI
Max Pressure Rise/Step (weakening)	+10 hPa
Movement & Duration
Avg Movement Speed	11.7 km/h
Tracking Time	360h (15 days)
Time as TD+ (≥34kt)	180h (7.5d)
Time as Storm+ (≥64kt)	93h (3.9d)
Peak Intensity & Range
Peak Intensity	01:00 23/11/2005 -12.1°N, 90.3°E
Latitude	-14.6°N – -3.1°N (11.5°)
Longitude	68.1°E – 94.7°E (26.6°)

BOM (Australia) RI

Energy
ACE (10⁴ (km/h)²)	39.07	High
PDI (10⁶ (km/h)³)	61.87
Intensification / Weakening
Max Wind Gain/Step	+15 km/h
Max Wind Gain/24h	+56 km/h	RI
Max Wind Loss/Step	-6 km/h
Pressure Variation
Max Pressure Drop/Step	-10 hPa
Max Pressure Drop/24h	-38 hPa	RI
Max Pressure Rise/Step (weakening)	+4 hPa
Movement & Duration
Avg Movement Speed	9.8 km/h
Tracking Time	138h (5.8 days)
Time as TD+ (≥34kt)	117h (4.9d)
Time as Storm+ (≥64kt)	69h (2.9d)
Peak Intensity & Range
Peak Intensity	19:00 22/11/2005 -11.8°N, 90.5°E
Latitude	-14.3°N – -4.5°N (9.8°)
Longitude	89.8°E – 95.6°E (5.8°)

NEUMANN RI

Energy
ACE (10⁴ (km/h)²)	62.56	Very High
PDI (10⁶ (km/h)³)	104.94
Intensification / Weakening
Max Wind Gain/Step	+15 km/h
Max Wind Gain/24h	+65 km/h	RI
Max Wind Loss/Step	-24 km/h
Movement & Duration
Avg Movement Speed	10 km/h
Tracking Time	264h (11 days)
Time as TD+ (≥34kt)	174h (7.3d)
Time as Storm+ (≥64kt)	111h (4.6d)
Peak Intensity & Range
Peak Intensity	07:00 23/11/2005 -12.5°N, 90.3°E
Latitude	-14.8°N – -3.7°N (11.1°)
Longitude	80.3°E – 95.1°E (14.8°)

Advanced Indices Legend

ACE: Accumulated Cyclone Energy - measures total storm activity

PDI: Power Dissipation Index - measures potential destructiveness

RI: Rapid Intensification - when wind increases >=30 kt/24h or pressure drops >=30 hPa/24h

Countries with Direct Landfall

Storm did not make landfall

Index	Meaning	Formula / Condition	Classification
ACE Accumulated Cyclone Energy	Accumulated Cyclone Energy. Measures the total energy generated by the storm during its lifetime. Only counts reports with wind ≥ 35 kt (TS level or higher).	`ACE = Σ(V_max²) / 10&sup4;` Unit: 10⁴ kt²	< 2: Low 2-6: Medium 6-15: High ≥ 15: Very High
PDI Power Dissipation Index	Power Dissipation Index. More sensitive than ACE to extremely strong storms due to using cubic power. Reflects potential destructive power.	`PDI = Σ(V_max&sup³;) / 10&sup6;` Unit: 10⁶ kt³	Higher value = greater cumulative destructive power
RI Rapid Intensification	Rapid Intensification - storm strengthens suddenly in a short time. Very dangerous as it is difficult to forecast and causes surprise for prevention efforts.	Wind increase ≥ 30 kt/24h or Pressure drop ≥ 30 hPa/24h	Has RI or Fast increase (≥20kt)
Max wind gain/step	Maximum wind increase between 2 consecutive reports (usually 6 hours apart). Shows the fastest local intensification rate.	`max(V_i+1 - V_i)` Unit: kt (km/h)	Positive value = storm strengthening
Max wind gain/24h	Maximum wind increase in a 24-hour window. Main criterion for determining Rapid Intensification (RI).	`max(V_t+24h - V_t)` RI if ≥ 30 kt/24h	≥ 30kt: RI ≥ 20kt: Fast
Max wind loss/step	Maximum wind weakening between 2 consecutive reports. Shows at which stage the storm weakened fastest.	`max(V_i - V_i+1)` Unit: kt (km/h)	Positive value = storm weakening
Max pressure drop/step	Maximum pressure drop between 2 consecutive reports. Pressure decrease = storm center strengthening. Reflects local deepening rate.	`max(P_i - P_i+1)` Unit: hPa	Higher value = faster strengthening
Max pressure drop/24h	Maximum pressure drop in a 24-hour window. Important index for evaluating explosive deepening / explosive intensification.	`max(P_t - P_t+24h)` Explosive if ≥ 30 hPa	≥ 30hPa: RI ≥ 20hPa: Strong
Max pressure rise/step	Maximum pressure rise between 2 consecutive reports. Pressure increase = storm weakening. Large value indicates rapid weakening (due to terrain interaction, landfall, etc.).	`max(P_i+1 - P_i)` Unit: hPa	Higher value = faster weakening
Average moving speed	Average moving speed of the storm center during the entire monitoring period by that agency.	`V_avg = S_total / T_total` Unit: kt (km/h)	Slow-moving storms (<15 km/h) usually cause prolonged heavy rain
Monitoring duration	Total time from first report to last report of that agency.	`T = t_end - t_start` Unit: hours (days)	Different agencies may monitor for different durations
TS+ Duration	Total hours with average wind ≥ 34 kt (Tropical Storm level or higher). Reflects how long the storm maintained significant intensity.	Average wind ≥ 34 kt	Longer storm = greater total damage
TY+ Duration	Total hours with average wind ≥ 64 kt (Typhoon level or higher). Storms maintaining this level longer have much greater destructive power.	Average wind ≥ 64 kt	Longer time at Typhoon level = more dangerous
Peak Intensity	Time and location (lat, lon) when the storm reached maximum wind according to each agency. Helps identify where the storm was strongest.	V_max = max(V_i)	Peak location helps assess danger for nearby areas
Latitude / Longitude	Spatial range of activity by latitude and longitude. Shows whether the storm affected area is wide or narrow.	min-max(lat), min-max(lon)	Large range = long trajectory, wide impact

Index

Meaning

Formula / Condition

Classification

ACE
Accumulated Cyclone Energy

Accumulated Cyclone Energy. Measures the total energy generated by the storm during its lifetime. Only counts reports with wind ≥ 35 kt (TS level or higher).

ACE = Σ(V_max²) / 10&sup4;
Unit: 10⁴ kt²

< 2: Low
2-6: Medium
6-15: High
≥ 15: Very High

PDI
Power Dissipation Index

Power Dissipation Index. More sensitive than ACE to extremely strong storms due to using cubic power. Reflects potential destructive power.

PDI = Σ(V_max&sup³;) / 10&sup6;
Unit: 10⁶ kt³

Higher value = greater cumulative destructive power

RI
Rapid Intensification

Rapid Intensification - storm strengthens suddenly in a short time. Very dangerous as it is difficult to forecast and causes surprise for prevention efforts.

Wind increase ≥ 30 kt/24h or Pressure drop ≥ 30 hPa/24h

Has RI or
Fast increase (≥20kt)

Max wind gain/step

Maximum wind increase between 2 consecutive reports (usually 6 hours apart). Shows the fastest local intensification rate.

max(V_i+1 - V_i)
Unit: kt (km/h)

Positive value = storm strengthening

Max wind gain/24h

Maximum wind increase in a 24-hour window. Main criterion for determining Rapid Intensification (RI).

max(V_t+24h - V_t)
RI if ≥ 30 kt/24h

≥ 30kt: RI
≥ 20kt: Fast

Max wind loss/step

Maximum wind weakening between 2 consecutive reports. Shows at which stage the storm weakened fastest.

max(V_i - V_i+1)
Unit: kt (km/h)

Positive value = storm weakening

Max pressure drop/step

Maximum pressure drop between 2 consecutive reports. Pressure decrease = storm center strengthening. Reflects local deepening rate.

max(P_i - P_i+1)
Unit: hPa

Higher value = faster strengthening

Max pressure drop/24h

Maximum pressure drop in a 24-hour window. Important index for evaluating explosive deepening / explosive intensification.

max(P_t - P_t+24h)
Explosive if ≥ 30 hPa

≥ 30hPa: RI
≥ 20hPa: Strong

Max pressure rise/step

Maximum pressure rise between 2 consecutive reports. Pressure increase = storm weakening. Large value indicates rapid weakening (due to terrain interaction, landfall, etc.).

max(P_i+1 - P_i)
Unit: hPa

Higher value = faster weakening

Average moving speed

Average moving speed of the storm center during the entire monitoring period by that agency.

V_avg = S_total / T_total
Unit: kt (km/h)

Slow-moving storms (<15 km/h) usually cause prolonged heavy rain

Monitoring duration

Total time from first report to last report of that agency.

T = t_end - t_start
Unit: hours (days)

Different agencies may monitor for different durations

TS+ Duration

Total hours with average wind ≥ 34 kt (Tropical Storm level or higher). Reflects how long the storm maintained significant intensity.

Average wind ≥ 34 kt

Longer storm = greater total damage

TY+ Duration

Total hours with average wind ≥ 64 kt (Typhoon level or higher). Storms maintaining this level longer have much greater destructive power.

Average wind ≥ 64 kt

Longer time at Typhoon level = more dangerous

Peak Intensity

Time and location (lat, lon) when the storm reached maximum wind according to each agency. Helps identify where the storm was strongest.

V_max = max(V_i)

Peak location helps assess danger for nearby areas

Latitude / Longitude

Spatial range of activity by latitude and longitude. Shows whether the storm affected area is wide or narrow.

min-max(lat), min-max(lon)

Large range = long trajectory, wide impact

ALVIN:BERTIE (2006)

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Advanced Meteorological Indices by Agency Automatically calculated from raw data

Advanced Indices Legend

Countries with Direct Landfall

ALVIN:BERTIE

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Weather Agencies (5 sources)

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Quick Stats

Agency Data Comparison

Indices Legend

Advanced Meteorological Indices by Agency Automatically calculated from raw data

Advanced Indices Legend

Countries with Direct Landfall

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