Published by the Nigerian Meteorological Agency (Nimet)

MARINE METEOROLOGICAL QUARTERLY BULLETIN

VOL XI NO II. April - June, 2013

PUBLISHED BY THE NIGERIAN METEOROLOGICAL AGENCY (NIMET) P. M. B 1215, Oshodi, Lagos. E-mail: [email protected]

July, 2013

CONTENTS Pages Contents ………………………………………………………………………………………………………… 1 General Terms ……………………………………………………………………………………………….. 2 Introduction …………………………………………………………………………………………………. 3

Quarterly Coastal Weather Review ………………………………………………………………. 6

Meteorological Data for Lagos and Eket Areas ………………………………………………. 9

Day- time Sea Surface Temperature (SST) over Eket in Akwa Ibom, State for April – June, 2013 ………………………………………………….……………………………………… 10

Day- time Sea Surface Temperature (SST) over Koko, Delta State for April – June, 2013 ………………………………………………………………………………………….. 11

Day- time Sea Surface Temperature (SST) over Calabar in Cross River, State for April – June, 2013 …………………………………………………………………………………………… 12

Sample of Daily Marine Weather Forecast ……………………………………………………… 13

Weather Outlook for the next Quarter……………………………………………………………… 15

PUBLISHED BY THE NIGERIAN METEOROLOGICAL AGENCY P. M. B 1215, Oshodi, Lagos. Tel: 234-8O23213456, E-mail: [email protected]

GENERAL TERMS

Inter-tropical discontinuity (ITD) - Transitional zone between dry north easterly winds and moisture laden south westerly winds. Ridge - An elongated zone of relatively high atmospheric pressure. Swell - Waves at point of observation which have travelled some distance from the area where they were generated at sea. Sea Waves - Sea waves are also known as wind waves. They are waves raised locally by wind blowing over a stretch of water. Tide - The regular rise and fall in the surface level of the oceans, caused by gravitational attraction of the moon and sun. HSM - Wave Height Sea Surface Temperature (SST) - The temperature of the sea surface representing the condition the surface mixed layer underlying the ocean skin.

FORECAST Slight - used for describing sea state: indicating wave height between 0.5 – 1.25 metres Moderate - used for describing sea state: indicating wave height between 1.25 – 2.50 metres Rough - used for describing sea state: indicating wave height between 2.50 – 4.0 metres Fair - used in describing weather condition: no precipitation or fog is expected

Visibility: - Good is between 10 – 20km Moderate is between 4000m – 10km Poor is between 1000 – 4000m Very poor is below 1000m

Wind: Light air - 1-3knots Light breeze - 4-6knots Gentle breeze - 7-10knots Moderate breeze- 11-16knots Fresh breeze - 17-21knots Strong breeze- 22-27knots 2 INTRODUCTION

The Nigerian coastal zone lies within Lat 4° 10’ to 6° 2’ N and Longitudes 2° 45’ to 8° 35’ E spanning about 850km of low-lying coastline. The coast is bordered by a narrow continental shelf of the Gulf of Guinea, shelf widths range from 15km in the west to about 67km in the

Niger Delta and about 87km off the Cross River estuary in the East. The Nigerian coastal zone comprises of Lagos, Ondo, Delta, Rivers, Bayelsa, Akwa Ibom and Cross River states and parts of

Edo state with about 25% of the estimated population of the country. There are high economic activities with Ports, harbor and major industries in the coastal area.

Nigerian Meteorological Agency is vested with the responsibility of monitoring weather and climate as its statutory functions. The Agency is working out modalities of having collaboration with other likeminded Organizations and Institutions, which will eventually enhance better development in Marine Meteorology and Oceanography.

The task of analyzing the observed weather pattern and changes with a view of informing the general public, marine users including ships and coastal dwellers is therefore given priority attention by the Agency. At present the Division is made up of five functioning operational coastal stations, which are: East mole, Nigerian Institute of Oceanography and Marine Research

(NIOMR) in Lagos, Eket in Akwa Ibom State, Koko in Delta state and Calabar marine station. Six other stations are being established while a buoy with marine sensors will soon be installed at the Lagos area of the Atlantic Ocean.

3 The Division issues daily marine weather forecasts for shipping and fishing industries, oil companies and other coastal users.

MISSION

The mission of Marine Meteorological Division is to make available to marine users at sea or on the coast, marine meteorological and related geophysical information which they require to the extent technically possible and to generate revenue for the Agency.

PRODUCTS AND SERVICES

 Observation, collation and analyses of all Marine Meteorological parameters.

 Dissemination of marine information to marine users.

 Issuing of daily Marine weather forecasts (Inshore & Shipping)

 Production of quarterly Marine Meteorological bulletin.

 Provision of special Marine services on request.

 Carrying out research in Marine Meteorology and Oceanography.

 Provision of consultancy services in the area of Marine Meteorology and

Oceanography.

 Capacity building through training of students on attachment.

 Teaching of Marine Meteorology in WMO Regional Meteorological Training

Institute, Oshodi.

4  Developing and maintaining necessary contacts with other institutions and

Establishments in and outside Nigeria in marine related activities through

appropriate Authority in the Agency.

 Participation in conferences on Oceanography and Marine Meteorological

matters.

 Generation of revenue from Marine services and products.

POTENTIAL USERS

 Shipping industry.

 Oil industry

 Fishing Industry

 Insurance companies

 Researchers from higher Institutions, Government Institutions and interested

bodies/individuals.

 Media and press.

 Engineering and construction companies in Coastal areas.

 Coastal Dwellers, Tourist etc.

 The General public.

 Government Corporations.

5 QUARTERLY COASTAL WEATHER REVIEW April

The ITD fluctuated between latitudes 10.9°N and 17.0°N, with an average latitudinal position of

14.0°N. Wind flow over the coastal area of the country was mainly Southwesterly with an average speed of 5 - 10kts occasionally 20kts. Coastal mean maximum temperature in Lagos and Eket areas were 32.8°C and °C respectively. The average Sea Surface Temperature for Koko was °C while it was 30.0°C in Eket and Calabar. The average value of the coastal Mean Sea

Level Pressure (MSLP) was 1012hPa while the St. Helena high pressure centre was between

1020hPa and 1028hPa with an average value of 1024hPa.

Adverse weather and flooding wrecked parts of the coastal area during the month. Places like

Lagos and parts of South-South area were affected by the storm. The sea state was slight to moderate while the sea surface temperature (SST) was warmer compared to the previous month.

Rainfall amount recorded in Lagos was 126.1mm. There were records of disruption of activities due to adverse weather as published in a number of National dailies. The Punch Newspaper reported on 9th , 10th, 17th and 23rd April, that flood sacked commercial hubs of Lagos, Ado- Ekiti

Warri and some other coastal areas after the down pour. On the 23rd, a 7 years old boy was killed by the storm at Ado- Ekiti. Structures were affected and damaged by the storm. Roofing sheets, vehicles, water tanks and electric cables were blown away and damaged at Ojodu area in Lagos.

Traders and residents lamented at Ikeja, Oyingbo, Apongbon and Mushin in Lagos.

The ITD continued its northward displacement from its average position in the previous month.

It fluctuated between latitudes 13.3°N and 17.0°N with an average position of approximately Lat

14.5°N, comparing this to the average position of 14.0°N for the month of April. This indicates the penetration of the south west monsoon further inland and more moisture.

Wind flow was mainly south westerly over the coastal area with moderate speed on the average.

The coastal mean sea level pressure (MSLP) fluctuated between 1010hPa and 1014hPa with an average value of 1012hPa while the St. Helena’s high pressure centre had highest value of

1028hPa.

Maximum temperature over Lagos area was 31.8°C while in Eket it was 29.9°C.

The average Sea Surface Temperature over Eket, Calabar and Koko were °C, 29.8°C and °C respectively.

The amount of rainfall recorded this month exceeded that of April in most parts of the coastal area. Victoria Island had 285.6mm, while Eket 318.7mm. Highest rainfall of 63.4mm was recorded on 29th over Eket area with above 70% of the month wet.

The sea state was slight to moderate and occasionally rough. There were disruption of coastal engineering works, transportation, commercial and some other activities over the coast as a result of flooding. Early morning Foggy conditions were not left out over the ocean.

7 June

The ITD continued its northward migration as the south west monsoon became well established.

It fluctuated between Lat. 14.6°N and 19.9°N with an approximately average position of 16.0°N.

This placed the ITD above the country. On the 850hPa chart, the flow pattern was mainly

Southwesterly, with force ranging between 5kts to 35kts.

The mean coastal maximum temperature at Lagos and Eket areas were 30.3°C and 28.3°C respectively. The Sea Surface Temperature (SST) was colder compared with the previous months in the quarter. Average SST at Eket and Koko and Calabar were 28.6°C respectively.

The mean surface pressure was 1011hPa, while the values of centre of the St. Helena’s high pressure ranged from 1024hPa to 1036hPa.

Rainstorms was well pronounced in the month, a number of activities were disrupted as major parts of the area experienced flood, motorists in Lagos were disrupted especially over Lekki- Epe road erosion. Calabar reported 116.0mm in three days of rainfall while Lagos reported 106.6mm of rain in a single day. Highest amount of rainfall was recorded for the quarter with value

300.2mm and 653.8mm in Lagos and Eket respectively.

Gusty wind was recorded on 3rd with maximum value of 32kts over Eket area. The sea state was moderate occasionally rough.

Port and Harbour operations and other coastal activities were also disrupted as a result of adverse weather. The adverse weather sent caution to the Government and people of the Coastal Area.

8 Meteorological Data for Lagos, Eket and Calabar Area

LAGOS AREA

MEAN Mean Mean Mean Rainfall Surf.Pres. Sea ITD Wind Min. Max. Amount st. Surf. position Wind Direction Speed Temp. Temp. (mm) Helena Temp. (°N) (Kts) (°C) (°C) hPa (°C) April 14.0 South westerly 15kts 25.5 32.8 126.1 1024 xxx May 14.5 South westerly 15kts 25.3 31.8 285.6 1024 xxx June 16.0 South westerly 18kts 24.8 30.3 300.2 1028 xxx

EKET AREA

MEAN Mean Mean Mean Rainfall Surf.Pres. Sea ITD Wind Min. Max. Amount st. Surf. position Wind Direction Speed Temp. Temp. (mm) Helena Temp. (°N) (Kts) (°C) (°C) hPa (°C) April 18.9 South westerly 15kts 24.7 30.6 220.5 1024 May 19.9 South westerly 15kts 23.9 29.9 318.7 1024 June 18.0 South westerly 18kts 23.7 28.3 653.8 1028

CALABAR AREA

MEAN Mean Mean Mean Rainfall Surf.Pres. Sea ITD Wind Min. Max. Amount st. Surf. position Wind Direction Speed Temp. Temp. (mm) Helena Temp. (°N) (Kts) (°C) (°C) hPa (°C) April 14.0 South westerly 15kts 24.1 32.1 159.9 1024 30.0 May 14.5 South westerly 15kts 24.1 31.7 271.3 1024 29.8 June 16.0 South westerly 18kts 24.0 30.1 306.8 1028 28.6

9 DAY – TIME SEA SURFACE TEMPERATURE (SST) OVER EKET, AKWA IBOM STATE FOR April - June, 2013. (DAILY AVERAGES IN °C) DAY April May June 1 29.2 27.8 28.1 2 27.8 28.6 28.3 3 28.9 27.8 25.8 10 4 29.2 28.2 26.9 5 27.2 28.5 26.8 DAY – 6 28.8 28.5 26.2 TIME LAGOON 7 28.7 27.6 27.8 8 29.5 28.1 25.8 9 28.4 28.6 26.3 10 27.5 25.0 27.9 11 28.7 27.4 27.1 12 29.2 27.6 25.8 13 28.2 26.5 27.6 14 26.9 28.3 27.4 15 27.7 27.1 26.2 16 27.7 28.6 26.1 17 28.2 25.7 25.7 18 28.2 27.0 25.2 19 28.5 26.9 26.0 20 29.1 27.9 26.1 21 28.4 28.0 25.9 22 27.6 28.7 26.8 23 28.8 27.7 25.4 24 26.0 28.4 26.5 25 28.0 26.9 25.4 26 27.7 26.7 26.6 27 28.0 27.8 25.7 28 28.3 27.3 25.5 29 28.3 27.2 26.5 30 29.0 26.3 26.9 31 Xxxx 28.4 - MEAN 28.3 27.6 26.5 TEMPERATURE (LT) AT VICTORIA ISLAND, LAGOS FOR APR.- JUN., 2013. (DAILY AVERAGES IN °C)

DAY APR. MAY. JUN. 1 30.8 29.7 27.8 2 29.5 29.6 27.4 3 29.7 29.8 27.1 4 30.3 30.0 28.0 5 30.0 29.7 28.5 6 30.2 29.4 28.3 7 30.3 30.3 28.6 8 29.2 29.4 27.9 9 27.9 29.9 27.7 10 30.4 30.2 28.4 11 30.4 28.3 27.1 12 30.5 29.7 28.6 13 30.4 29.1 28.1 14 30.0 29.3 29.0 15 29.5 28.2 27.9 16 30.9 29.8 27.7 17 29.8 29.2 28.7 18 30.3 29.0 28.2 19 30.3 29.3 28.1 20 28.8 29.9 27.6 21 29.9 29.0 27.6 22 29.0 30.1 28.5 23 29.4 29.3 27.9 24 29.5 29.9 27.8 25 30.0 29.8 27.9 26 28.4 28.7 28.3 27 29.7 29.1 27.5 28 29.9 29.1 27.7 29 30.0 28.4 27.5 30 29.8 29.1 26.3 31 Xxxx 29.5 Xxxx MEAN 29.8 29.4 27.9

DAY – TIME SEA SURFACE TEMPERATURE (SST) OVER KOKO, DELTA STATE FOR April - June, 2013. (DAILY AVERAGES IN °C) DAY April May June 1 29.4 29.8 30.5 2 29.1 29.4 29.4 3 29.4 30.2 29.9 4 29.8 29.8 29.6 5 30.6 29.6 30.2 6 30.1 29.9 29.6 7 29.3 29.4 29.6 8 29.9 30.1 29.0 9 29.5 30.1 29.7 10 29.2 29.6 29.1 11 30.2 29.7 29.1 12 30.5 30.2 30.0 13 28.4 28.6 29.6 14 29.4 30.2 29.5 15 29.0 29.1 29.9 16 29.9 30.5 29.1 17 29.6 30.0 28.4 18 29.3 30.1 28.9 19 29.0 30.0 29.8 20 28.7 29.9 29.2 21 29.7 30.0 29.3 22 29.2 30.5 29.3 23 29.3 28.9 29.8 24 30.2 29.7 29.6 25 28.5 29.3 30.2 26 28.5 29.9 29.9 27 29.9 30.3 29.1 28 29.7 29.5 30.2 29 30.1 30.3 29.4 30 29.0 29.9 29.5 31 Xxx 28.9 - MEAN 29.5 29.8 29.6

11 DAY – TIME SEA SURFACE TEMPERATURE (SST) OVER Calabar, CROSS RIVER STATE FOR April - June, 2013. (DAILY AVERAGES IN °C) DAY April May June 1 27.1 25.4 25.8 2 27.3 25.7 25.8 3 26.9 25.4 25.6 4 26.9 25.5 25.7 5 27.1 25.4 25.5 6 26.9 25.4 25.7 7 26.4 25.5 25.6 8 26.7 25.5 25.6 9 26.5 25.6 25.6 10 26.4 25.7 25.8 11 26.5 25.7 26.1 12 26.8 26.0 26.1 13 26.6 26.3 26.3 14 26.6 26.3 26.4 15 26.4 26.3 26.6 16 26.7 26.5 26.3 17 26.7 26.5 26.5 18 26.5 26.3 26.8 19 26.1 26.6 26.6 20 26.3 26.2 26.7 21 25.6 26.4 26.9 22 25.5 26.1 26.6 23 25.6 26.4 26.7 24 25.7 25.8 26.5 25 25.5 25.8 26.8 26 25.5 25.9 27.2 27 25.5 25.9 27.6 28 25.5 25.9 27.2 29 25.5 26.0 27.2 30 25.4 25.9 27.2 31 25.4 26.1 - MEAN 26.3 25.9 26.3

12 SAMPLE OF DAILY MARINE FORECAST

Forecast for Inshore Waters of Nigeria up to 20km offshore (60 13'N, 2054'E to 40 32'N, 80 23'E) Issued by Nigerian Meteorological Agency, (NIMET) at 1500UTC on Tue. 11th Jun. 2013. Period of Forecast: 1800 UTC Tue. 11th to 1800 UTC Wed. 12th Jun. 2013.

WARNINGS: NIL

General Situation: The forecast area is expected to be under the influence of low pressure system with values ranging from 1012 - 1014hPa for the period of forecast, except a deepening to 1011hPa at about 1500UTC. Convective activities are expected with light to moderate occasionally fresh breeze.

Calabar, Eket and Port Harcourt coastal waters 24 Hour forecast Wind: Southerly veering south-westerly, 5 -10kts occasionally 18kts. Sea state: Large wavelets; crests begin to break; foam of glassy appearance; chances of scattered white horses to small waves, becoming longer; fairly frequent white horses. (Slight to moderate). Sig. Wave Ht: 1.2m Swell Ht: 0.6m – 1.2m. Tide: Cal – high: 2.8m (1845&0745 UTC), low: 0.5m (0135UTC) PHC–high: 2.2m (1910UTC), low: 0.2m (0105UTC) Weather: Rain, thunderstorm later. Visibility: Moderate (4000m -10km).

Outlook for the following 24hrs: Wind: South-westerly, 5-10kts, occasionally 15kts. Sea State: Large wavelets; crests begin to break; foam of glassy appearance; chances of scattered white horses to small waves, becoming longer; fairly frequent white horses (Slight to moderate). Weather: Fair, rain with chances of thunderstorm later. Visibility: Moderate (4000m- 10km).

Warri, Koko and Aiyetoro coastal waters 24 hr forecast Wind: South-westerly 5 -10kts occasionally 15kts. Sea State: Large wavelets; crests begin to break; foam of glassy appearance; chances of scattered white horses to small waves, becoming longer; fairly frequent white horses (Slight to moderate). Sig. Wave Ht: 1.5m Swell Ht: 0.9 – 1.5m Tide: Warri – high: 1.7m (2115UTC), low: 0.5m (0320UTC) Weather: Fair, chances of rain/ thunderstorm later. Visibility: Moderate (4000m- 10km).

Outlook for the following 24hrs Wind: South-westerly, 5 -10kts occasionally 15kts. Sea State: Small waves, becoming longer; fairly frequent white horses (Moderate). Weather: Fair, rain /thunderstorm later Visibility: Moderate (4000m - 10km). Lagos Coastal Waters 24hr forecast: Wind: South-westerly, 5 -10kts occasionally 15kts. Sea State: Large wavelets; crests begin to break; foam of glassy appearance; chances of scattered white horses to small waves, becoming longer; fairly frequent white horses (Slight to moderate). Sig. Wave Ht: 1.5m Swell Ht: 0.9 – 1.5m Tide: High: 0.8m (0550UTC and 1730UTC), low: -0.2m (2350UTC) Weather: Fair, chances of rain/ thunderstorm later. Visibility: Moderate (4000m - 10km).

Outlook for the following 24hrs. Wind: South westerly, 5-12kts. Sea State: Large wavelets; crests begin to break; foam of glassy appearance; chances of scattered white horses to small waves, becoming longer; fairly frequent white horses (Slight to moderate). Weather: Fair, rain, chances of thunderstorm later. Visibility: Moderate (4000m -10km).

SHIPPING FORECAST TO 650KM OFFSHORE (60 13'N, 20 54'E - 40 32'N, 8023'e to equator) ISSUED BY NIGERIAN METEOROLOGICAL AGENCY (NIMET), at 1500 UTC on Tue. 11th Jun. 2013. VALID FOR: 1800 UTC Tue. 11th to 1800 UTC Wed. 12th Jun, 2013.

WARNINGS:

GENERAL SYNOPSIS: The forecast area will be under the influence of a low pressure system with values of 1013 - 1015hPa from 1800UTC till about 1200UTC the following day. It is expected to deepen to 1012hPa at about 1500 UTC and remain quasi stationary to the end of forecast period. The centre of St Helena's high pressure system which has been 1024hPa will remain quasi stationary throughout the forecast period. Light to moderate occasionally fresh breeze with convective activities are expected. THE AREA FORECASTS FOR THE NEXT 24 HOURS

WIND: SOUTH WESTERLY, 5 –14kts, occasionally 18kts. SEA STATE: small waves, becoming longer; fairly frequent white horses (moderate). SIG. WAVES HT: 1.5m SWELL HT: 0.6 – 1.5m WEATHER: FAIR, RAIN /THUNDERSTORM LATER. VISIBILITY: MODERATE (4000m-10km).

END. T+00 sig. wave ht. (ft) 00Z 12th June, T+18 sig. wave ht. (ft) 12Z 12th June, 2013 2013 th T+00 sig. wave ht. (ft) 00Z 11th June, T+18 sig. wave ht. (ft) 18Z 11 June, 2013 2013

T+00 sig. wave ht. (ft) 00Z 12th June, T+18 sig. wave ht. (ft) 12Z 12th June, 2013 2013 WEATHER OUTLOOK FOR THE NEXT QUARTER (July – Sept, 2013)

The ITD position which commenced its southward movement at the later part of the quarter

(July-Sept, 2012) will continue to retreat, reaching its southernmost position toward the end of next quarter (Oct.-Dec., 2012). This will leave major part of the country under the influence of dry dusty northeasterly wind which will reduce visibility in dust haze towards the end of the quarter. Rainfall will still be experienced in parts of the coastal area especially South-South due to coastal phenomenon. There will be chances of active waves which may result in storm surges.

The sea surface temperature is expected to reach its second maximum peak around November to early December. There will be frequent early morning mist/ fog towards the end of this quarter which could disrupt coastal operations.