Indonesian Weather Bulletin for Shipping
( Metarea XI)

BMKG Jakarta, Tuesday 20 May 2025 At 0600 UTC

Part I : Warning

NIL

Part II : General Synopsis

Monday 19 May 2025 at 12 UTC NORTHEASTERLY TO SOUTHEASTERLY LIGHT TO MODERATE FLOW IN THE NORTHERN PART OF INDONESIA SOUTHEASTERLY TO SOUTHWESTERLY GENTLE TO FRESH FLOW IN THE SOUTHERN PART OF INDONESIA

Part III : Area Forecasts

Valid until Wednesday 21 May 2025 at 06 UTC

MALACCA STRAIT

Northwesterly
0-15 kt
Moderate Sea

INDIAN OCEAN WESTERN OF ACEH

Northeasterly
6-11 kt
Moderate Sea

INDIAN OCEAN WESTERN OF LAMPUNG

Southeasterly
8-22 kt
Moderate Sea

INDIAN OCEAN SOUTHERN OF JAVA

Southeasterly
14-24 kt
Moderate Sea

INDIAN OCEAN SOUTHERN OF BALI

Southeasterly
10-21 kt
Moderate Sea

NORTH NATUNA SEA

Northerly
2-21 kt
Moderate Sea

KARIMATA STRAIT

Easterly
1-21 kt
Slight Sea

JAVA SEA

Easterly
12-24 kt
Moderate Sea

MAKASSAR STRAIT

Easterly
5-23 kt
Slight Sea

BALI SEA

Easterly
4-20 kt
Slight Sea

SUMBAWA SEA

Easterly
4-18 kt
Slight Sea

FLORES SEA

Easterly
4-17 kt
Slight Sea

BANDA SEA

Southeasterly
0-27 kt
Moderate Sea

CERAM SEA

Northeasterly
0-18 kt
Slight Sea

SULAWESI SEA

Northerly
0-22 kt
Slight Sea

MOLLUCA SEA

Northerly
0-21 kt
Slight Sea

WESTERN PART OF PACIFIC OCEAN

Northerly
0-12 kt
Slight Sea

ARAFURA SEA

Easterly
1-28 kt
Moderate Sea

⚠️ Important Notes

Please be aware, wind gusts can be a further 40 percent stronger than the averages given here, and maximum waves may be up to twice the significant height

Reference Scales

Beaufort Wind Scale

ForceDescriptionSpeed (knots)
0Calm< 1
1Light air1-3
2Light breeze4-6
3Gentle breeze7-10
4Moderate breeze11-16
5Fresh breeze17-21
6Strong breeze22-27
7Near gale28-33
8Gale34-40
9Strong gale41-47

Douglas Sea Scale

GradeDescriptionHeight (m)
0Calm (Glassy)0
1Calm (Rippled)0-0.1
2Smooth0.1-0.5
3Slight0.5-1.25
4Moderate1.25-2.5
5Rough2.5-4
6Very rough4-6
7High6-9
8Very high9-14
9Phenomenal>14
Download document inPDF Format