This is storm DAVID that was active in 1976 in the S. Pacific region with maximum winds of 157 km/h.

What was the maximum intensity of the storm?

Max Wind: 157 km/h. Min Pressure: hPa.

storm DAVID (1976) - Track and intensity details

Name: storm DAVID
Start: 1976-01-11
End: 1976-01-22
Location: S. Pacific

DAVID (1976)

Storm Code: 1976011S13177 | Region: S. Pacific
Active from 11/01/1976 to 22/01/1976 (12 days)

157 km/h

10-min Wind (BOM)

Level 14

945 hPa

Min Pressure

4,755 km

Distance

Forecast Agencies

Agency	Max Intensity	Trajectory	Energy	highest_classification
WMO (International)	157	955	33	4,235	10.98	13.21	Level 14 - Violent Storm
WELLINGTON	157	945	111	4,067	43.97	55.52	Level 14 - Violent Storm
TD9636 (coordinates_only)	~	~	127	4,755	~	~	Undefined
JTWC (coordinates_only)	~	~	119	4,161	~	~	Undefined
DS824 (coordinates_only)	~	~	119	4,161	~	~	Undefined
NEUMANN	157	961	107	3,735	44.93	60.98	Level 14 - Violent Storm
BOM (Australia)	157	961	98	3,237	39.24	53.42	Level 14 - Violent Storm

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)

157

955

4,235

10.98

13.21

Level 14 - Violent Storm

WELLINGTON

157

945

111

4,067

43.97

55.52

Level 14 - Violent Storm

TD9636
(coordinates_only)

127

4,755

Undefined

JTWC
(coordinates_only)

119

4,161

Undefined

DS824
(coordinates_only)

119

4,161

Undefined

NEUMANN

157

961

107

3,735

44.93

60.98

Level 14 - Violent Storm

BOM (Australia)

157

961

3,237

39.24

53.42

Level 14 - Violent Storm

Advanced Meteorological Indices by Agency Automatically calculated from raw data

WMO (International)

Energy
ACE (10⁴ (km/h)²)	10.98	Medium
PDI (10⁶ (km/h)³)	13.21
Intensification / Weakening
Max Wind Gain/Step	+28 km/h
Max Wind Gain/24h	+46 km/h	Fast
Max Wind Loss/Step	-46 km/h
Pressure Variation
Max Pressure Drop/Step	-15 hPa
Max Pressure Drop/24h	-25 hPa	Strong
Max Pressure Rise/Step (weakening)	+10 hPa
Movement & Duration
Avg Movement Speed	16.1 km/h
Tracking Time	263h (11 days)
Time as TD+ (≥34kt)	173h (7.2d)
Time as Storm+ (≥64kt)	98h (4.1d)
Peak Intensity & Range
Peak Intensity	12:00 19/01/1976 -21.7°N, 151.9°E
Latitude	-27.9°N – -13°N (14.9°)
Longitude	142.2°E – 177.4°E (35.2°)

WELLINGTON

Energy
ACE (10⁴ (km/h)²)	43.97	High
PDI (10⁶ (km/h)³)	55.52
Intensification / Weakening
Max Wind Gain/Step	+7 km/h
Max Wind Gain/24h	+46 km/h	Fast
Max Wind Loss/Step	-13 km/h
Pressure Variation
Max Pressure Drop/Step	-5 hPa
Max Pressure Drop/24h	-25 hPa	Strong
Max Pressure Rise/Step (weakening)	+5 hPa
Movement & Duration
Avg Movement Speed	16.9 km/h
Tracking Time	240h (10 days)
Time as TD+ (≥34kt)	195h (8.1d)
Time as Storm+ (≥64kt)	99h (4.1d)
Peak Intensity & Range
Peak Intensity	19:00 17/01/1976 -19.8°N, 159.7°E
Latitude	-25.5°N – -13°N (12.5°)
Longitude	142.3°E – 177.3°E (35°)

TD9636

Movement & Duration
Avg Movement Speed	17.2 km/h
Tracking Time	276h (11.5 days)
Peak Intensity & Range
Latitude	-28.4°N – -12.9°N (15.5°)
Longitude	141.9°E – 177.4°E (35.5°)

JTWC

Movement & Duration
Avg Movement Speed	16.5 km/h
Tracking Time	252h (10.5 days)
Peak Intensity & Range
Latitude	-28.4°N – -14.4°N (14°)
Longitude	142°E – 172.2°E (30.2°)

DS824

Movement & Duration
Avg Movement Speed	16.5 km/h
Tracking Time	252h (10.5 days)
Peak Intensity & Range
Latitude	-28.4°N – -14.4°N (14°)
Longitude	142°E – 172.2°E (30.2°)

NEUMANN

Energy
ACE (10⁴ (km/h)²)	44.93	High
PDI (10⁶ (km/h)³)	60.98
Intensification / Weakening
Max Wind Gain/Step	+9 km/h
Max Wind Gain/24h	+46 km/h	Fast
Max Wind Loss/Step	-22 km/h
Pressure Variation
Max Pressure Drop/Step	-2 hPa
Max Pressure Drop/24h	-11 hPa
Max Pressure Rise/Step (weakening)	+5 hPa
Movement & Duration
Avg Movement Speed	17.3 km/h
Tracking Time	216h (9 days)
Time as TD+ (≥34kt)	168h (7d)
Time as Storm+ (≥64kt)	106h (4.4d)
Peak Intensity & Range
Peak Intensity	13:00 19/01/1976 -21.8°N, 152°E
Latitude	-27.9°N – -14.4°N (13.5°)
Longitude	142.3°E – 172.2°E (29.9°)

BOM (Australia)

Energy
ACE (10⁴ (km/h)²)	39.24	High
PDI (10⁶ (km/h)³)	53.42
Intensification / Weakening
Max Wind Gain/Step	+4 km/h
Max Wind Gain/24h	+37 km/h	Fast
Max Wind Loss/Step	-31 km/h
Pressure Variation
Max Pressure Drop/Step	-2 hPa
Max Pressure Drop/24h	-11 hPa
Max Pressure Rise/Step (weakening)	+5 hPa
Movement & Duration
Avg Movement Speed	16.9 km/h
Tracking Time	192h (8 days)
Time as TD+ (≥34kt)	148h (6.2d)
Time as Storm+ (≥64kt)	87h (3.6d)
Peak Intensity & Range
Peak Intensity	12:00 19/01/1976 -21.8°N, 151.8°E
Latitude	-27.9°N – -15.4°N (12.5°)
Longitude	142.1°E – 167.4°E (25.3°)

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

🏳️ Australia

WMO 113 km/h Level 11

-22.00°, 149.52° 1976-01-19 13:56:07

MetService NZ 115 km/h Level 11

-22.17°, 149.57° 1976-01-19 13:43:21

TD9636

-21.84°, 149.48° 1976-01-19 12:44:31

JTWC

-21.84°, 149.48° 1976-01-19 12:44:31

DS824

-21.84°, 149.48° 1976-01-19 12:44:31

NEUMANN 148 km/h Level 13

-22.09°, 149.92° 1976-01-19 14:56:11

BOM 94 km/h Level 10

-22.03°, 149.52° 1976-01-19 15:15:07

🇻🇺 Vanuatu

MetService NZ 74 km/h Level 8

-15.88°, 167.22° 1976-01-13 11:28:11

Values are interpolated at landfall time and may differ from actual data.

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

DAVID (1976)

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Advanced Meteorological Indices by Agency Automatically calculated from raw data

Advanced Indices Legend

Countries with Direct Landfall

DAVID

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DAVID (1976)

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Comparison Storms 0

Weather Agencies (7 sources)

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Track List (0 points)

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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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