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Sources: BBC, National Weather Services, Intellicast, Space Science and Engineering Center, the Met Office, Yahoo! Weather
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TODAY’S HEADLINES
EL NIÑO
The important and far-reaching ocean-atmosphere phenomenon called El Niño has been developing in recent weeks. Click here (a) to read about the developments and their possible consequences (b) to find links to sites that provide detailed information about El Niño.
TODAY’S
EXTREMES
Hottest: Two Boats School, Ascension, 34°C
Coldest: Rantakylan Koulu, Mikkeli, Finland, -17.5°C
Windiest: Pinewood School, near Swindon, England, 68 km/h
Wettest: Peterhouse, Zimbabwe, 18 mm
TODAY’S REVIEW OF METLINK
OBSERVATIONS
Have you looked at today’s weathercams? If not, click here.
To view today’s observations in the database, click here.
To find out how your observations compare with the average for March, click here.
NB: It is early spring in the northern hemisphere, early autumn in the southern.
AUSTRALIA, NEW ZEALAND, INDIA AND INDONESIA
Pembroke School, New Zealand. 10 am Local Time (21:00 GMT on 14 March). Another pleasant day. Seven oktas of cloud, though (altostratus). Wind 9 km/h from the north-west. Temperature 19.2°C. Maximum temperature 20°C, minimum 7.0°C.
Millmerran State School, Queensland. Three observations today. Sunny, hot and humid at 8.45 am Local Time (22:45 GMT on 14 March). Cloudless. Wind Force 1 from the east. temperature 20.2°C. Humidity less at 11.13 am. Fallen from 62% to 45%. Temperature now 24.0°C. Now 1 okta of cumulus cloud. Wind still Force 1 but from the south-east. A few more cumulus clouds (3 oktas) at 12.56 pm. Temperature now 27.1°C. Wind south-west 9 km/h. Maximum temperature 32.2°C, minimum 14.4°C.
Greenwood Senior High School, Western Australia. Also three observations today. Had "a hot and sticky warm night" and "still no rain". Temperature 29.4°C at 12.30 pm Local Time (04:30 GMT). Relative humidity 45%. Cloud 4 oktas of cirrus, cumulus and stratocumulus. Wind 9 km/h from the east. Wind then increased: 24 km/h at 1.30 pm (from the south-west). Cloud now 8 oktas of stratocumulus. Temperature dropped to 26.8°C. Later in the day "tried hard to rain but just spat". Temperature at 10.05 pm 21.4°C. Wind very light again (Force 1 from the west). Cloud now 5 oktas of stratocumulus. Maximum temperature 30.1°C, minimum 21.4°C.
Donald High School, Victoria. "A fine sunny day with gathering cloud in the west late in the afternoon". Only 1 okta of cloud (cirrus) at 4 pm Local Time (05:00 GMT). Wind south-west 9 km/h. Temperature 29°C. Maximum temperature 32°C, minimum 11°C.
Marine Discovery Centre, Tasmania. "A day of varying weather conditions: rain, sunshine, some wind". Wind from the south-east 9 km/h at 4.30 pm Local Time (05:30 GMT). Temperature 20°C. Maximum temperature 20°C, minimum 14°C.
AFRICA AND ASCENSION
Peterhouse, Zimbabwe. "Clear now after yesterday’s rain" (18 mm measured). Temperature at 8 am Local Time (06:00 GMT) 20.3°C. Relative humidity 68%. Only 4 oktas of cloud (altostratus and altocumulus). Wind from the north-east, 9 km/h. Maximum temperature 27.4°C, minimum 18.6°C.
Christian Brothers’ College, Bulawayo, Zimbabwe. Rain of medium intensity. Temperature 19°C at 7.40 am Local Time (05:40 GMT). Wind very light (Force 1 from the north-east). Cumulus clouds. Maximum temperature 31°C, minimum 17°C.
Kgaswe Primary School, Botswana. Cloudless with a very light easterly wind (Force 1). Temperature 19°C at 8 am Local Time (06:00 GMT). Maximum temperature 23°C, minimum 19°C.
Micklefield School, Cape Town, South Africa. "A nice day for the beach and a swimming gala". No cloud. Wind from the north-east 15 km/h. Temperature 23°C at 10.30 am Local Time (08:30 GMT). Maximum temperature 25°C, minimum 19°C.
Highbury Preparatory School, KwaZulu Natal, South Africa. "Some good-looking cumulus clouds but will it rain? We don’t think so"! Cloud at 1 pm Local Time (11:00 GMT) 6 oktas (cumulus and cirrus). Wind Force 1 from the south-east. Temperature 25°C. Maximum temperature 27°C, minimum 18°C.
Grantleigh College, KwaZulu Natal, South Africa. "Very clammy and humid. Typical of this time of year. Cannot wait for winter." Calm at 11 am Local Time (09:00 GMT). Temperature 25.7°C and cloud 6 oktas of altocumulus. Maximum temperature 28.9°C, minimum 23.4°C.
Collegiate High School, Port Elizabeth, South Africa. "Clear, calm and warm weather". Cloudless at 1.30 pm Local Time (11:30 GMT). Wind 9 km/h from the east. Temperature 26.5°C. Maximum temperature 27.6°C, minimum 13.5°C.
Greenside High School, Gauteng, South Africa. "Very hot conditions and little chance of rain if any wind coming from the north-east". Wind from the east at 2.30 pm (12:30 GMT) but almost calm. Cloud 3 oktas of cumulus. Temperature 29°C. Maximum temperature 29°C, minimum 13°C.
Penryn College, Mpumalanga, South Africa. "A relief as humidity was routinely 90% recently. Beautiful sunset tonight." Relative humidity 50% at 1 pm Local Time (11:00 GMT). Temperature 26°C. Cloud 3 oktas of stratocumulus. Wind 9 km/h from the south-east. Maximum temperature 27°C, minimum 20°C.
Two Boats School, Ascension Island. "Hot and sunny". Wind 9 km/h from the north-east at 12.30 pm Local Time (12:30 GMT).Cloud 3 oktas of cumulus. Temperature 28°C. Maximum temperature 34°C, minimum 20°C.
EUROPE
Rantakylan Koulu, Mikkeli, Finland. "Cold at night (-17°C) but 20 degrees warmer at noon. Sunny and nice." Only 1 okta (of cirrus cloud) at 12 noon Local Time (10:00 GMT). Wind from the west Force 1. Temperature +1.5°C. maximum temperature 2.4°C, minimum —17.5°C.
Vasa övningsskola, Vasa, Finland. "Beautiful weather conditions". Calm and cloudless at 3.15 pm Local Time (13:15 GMT). Temperature 3.6°C. Maximum temperature 9.4°C, minimum —7.0°C.
Bor School, near Värnamo, Sweden. "Sunny. Blue sky. Ground covered with white frost. Cold and calm." No cloud and no wind at 8 am Local Time (07:00 GMT). Temperature —5.2°C. Maximum temperature 4.9°C, minimum —8.2°C.
Oslo International School, Oslo, Norway. Calm and cloudless at 12.45 pm Local Time (11:45 GMT). Temperature 4.1°C. Maximum temperature 5.5°C, minimum —8.5°C.
Aizpute Secondary School, Aizpute, Latvia. Cloudless at 1.07 pm Local Time (11:07 GMT). Wind from the north-east 15 km/h. Temperaure 5.2°C. Maximum temperature 5.2°C, minimum 2.3°C.
Aalborg International School, Aalborg, Denmark. "A clear cold and fresh day". No cloud at 10.15 am Local Time (09:15 GMT). Wind Force 1 from the east. Temperature 3°C. Maximum temperature 7°C, minimum 0°C.
Lycée Robert-Schuman, Luxembourg. "Slowly clearing up" after rain. Cloud at 11.25 am Local Time (10:25 GMT) 7 oktas of altocumulus and altostratus. Quite windy: 24 km/h (from the south). Temperature 12.5°C. Maximum temperature 20.5°C, minimum 4.5°C.
Strasbourg, France. Three observations: 8.30 am Local Time (07:30 GMT), 1 pm and 5.30 pm. Quite a variation during the day. Dry, calm and overcast this morning. "Clearing noon to hazy sunshine". "Gloomy gathering cloud during afternoon". Cloud at 8.30 am 8 oktas of stratus. Temperature then 5.0°C. Later, 1 pm, wind very light (Force 1 from the south-west). Cloud 3 oktas of stratocumulus and temperature 7.0°C. Overcast again at 5.30 pm, with 8 oktas of stratocumulus. Temperature then 9.0°C and wind the same as at 1 pm. Maximum temperature 9.0°C, minimum 5.0°C.
Carmen Sylva High School, Constanta, Romania. Two observations: one at 7.30 am Local Time (05:30 GMT), the other at 6 pm Local Time. Sunny in the morning with a light (9 km/h) wind from the north-east. Still sunny in the afternoon, with only 1 okta of cirrus cloud. "The weather is wonderful", the students wrote. Temperature in the morning 8.4°C. Temperature in the afternoon 13.7°C. Maximum temperature 14.4°C, minimum 7.6°C.
International School of Milan, Italy. Temperature 12°C at 11 am Local Time (10:00 GMT). Wind light (Force 1 from the south-west). Cloud 6 oktas of stratus.
Vicálvaro Primary School, Madrid, Spain. Two observations today: one at 9 am Local Time (08:00 GMT), the other at 3.25 pm. "Cold and cloudy" this morning. "It seems winter is coming instead of spring". Rainfall total measured this morning 5.6 mm. Cloud 6 oktas of cumulonimbus and altostratus. Wind Force 1 from the west. Temperature 8°C. Quite windy in the afternoon: 33 km/h (from the south-west). A gusty wind, the students said. Temperature 11°C. Cloud 8 oktas of cumulonimbus. Maximum temperature 17°C, minimum 6°C.
IES Vidal i Barraquer, Tarragona, Spain. "A sunny day" (what a contrast to Madrid). Cloud 2 oktas of cirrus and cumulus at 12.10 pm Local Time (11:10 GMT). Wind 9 km/h from the west. Temperature 16°C. Maximum temperature 16.0°C, minimum 9.2°C.
The United Kingdom
Windy, bright and cold at Farr
High School (north coast of
Scotland). Wind 44 km/h from the south-east at 9 am. Cloud 4 oktas of
cumulus and stratus. Temperature 5°C. Maximum temperature
7.2°C, minimum 2.2°C. Also windy cold and sunny at
Paible School (North Uist). Cloud 3 oktas of nimbostratus
at 9.30 am. Wind 33 km/h from the south-east. Temperature 5.9°C.
Maximum temperature 13.1°C, minimum 1.1°C. Quite cold, too,
at Beaconhurst
School (near Stirling).
Temperature 4.8°C at 11.17 am. Chilly also in Cumbria.
Temperature 5°C at Keswick School
at 12.50 pm and the wind 24 km/h (from the north-east).
In Lancashire, today was "another ear-stinging day" at
St Patrick’s Primary
School, near Preston. Wind 44
km/h from the north. Sky overcast. It was not much better at
Queen’s Park Community
Technology College,
Blackburn, where the wind speed at 12.50 pm was 33 km/h (from the
east, a cold direction at this time of year). Overcast and the
temperature 5°C.
The weather was no better farther south. Indeed, rain fell for
several hours in Reading, from about 10 am to early afternoon.
Honeybourne First
School in Worcestershire
reported 8 oktas of nimbostratus cloud at 9 am and the students of
Edgbaston High School for
Girls reported that the
weather was "very dark and windy" at 10.30 am. Slight drizzle was
falling at Pinewood
School near Swindon at 11 am
and slight rain was falling at Coed Cae Junior School in south-east Wales at 2 pm. Slight drizzle was
falling, too, at Lindfield
Primary School in West Sussex
at mid-day. Bristol Cathedral
School measured 6.5 mm of
rain at 9 am. The wind speed then was 24 km/h (from the east) and the
temperature 4°C. "Overcast and cold" was the verdict of the
students.
The students of Radley
College in Oxfordshire said
it was a "cold windy and damp" day. "Feels freezing; a miserable dull
day", said the students at St
Oswald’s Primary School
in Sheffield. "Dull, overcast and feels very cold" was the report
from the Royal Hospital
School in Suffolk. The
students who run Pitsford Hall
Weather Station in
Northamptonshire measured 4.5 mm of rain at 9 am, when the
temperature was 5.1°C, the relative humidity 97%, the wind speed
24 km/h (from the south-east) and the cloud 8 oktas of stratus.
Spring has certainly deserted the United Kingdom!
NORTH AND SOUTH AMERICA
The British School, Punta Arenas, Chile. Slight rain at 5 pm Local Time (21:00 GMT). Cloud 7 oktas of stratocumulus and cumulonimbus. Temperature 10°C.
Pasadena City College, California, USA. Temperature 16°C at 3 pm Local Time (23:00 GMT). Completely overcast (with cumulonimbus and stratus) but calm. "Rain expected by Sunday". Maximum temperature 19°C, minimum 8°C.
Peninsula Elementary School, Moses Lake, Washington State, USA. Overcast at 11 am Local Time (19:00 GMT). Cloud 7 oktas of altostratus and cumulonimbus. Wind 9 km/h from the north-east. Temperature 8.3°C. Maximum temperature 12.8°C, minimum 0.0°C.
Howell Middle School, Victoria, Texas, USA. Slight drizzle at 11 am Local Time (17:00 GMT). Completely overcast. Relative humidity 78%. Temperature 25°C. Maximum temperature 26°C, minimum 18°C.
Fernley Intermediate School, Nevada, USA. "Breezy, cold and awaiting the next storm". Sky cloudless, though. Temperature at 8.16 am (16:16 GMT) only +1°C.
Cardinal Gibbons High School, Raleigh, North Carolina, USA. Completely overcast at 7.38 am (12:38 GMT). Wind 9 km/h from the north-east. "Very cloudy but no precipitation", the students reported.
INTRODUCTION TO ATMOSPHERIC SYSTEMS
For information about atmospheric circulations, visit the Notes sections of the MetLink reports for 13 and 14 March.
INTRODUCTION TO SATELLITE IMAGES
On the so-called ‘visible’ images from satellites, what you see is more or less what you would see with your own eyes if you were in the satellite and looking in black and white.
On the so-called ‘infra-red’ images, the whitest areas are the coldest and the blackest the hottest. Thus, high clouds (e.g. the tops of cumulonimbus anvils and the sheets of cirrus clouds ahead of warm fronts) show as white areas. Medium-level clouds and very cold land areas show as grey.
On the so-called ‘water vapour’ images, the whitest areas are the most humid, the blackest areas the driest. The water vapour indicated by these images tends to be in the upper half of the troposphere, not lower down.
For information on how to obtain satellite images of the highest quality, see the Notes sections of the MetLink reports for 11, 12, 13 and 14 March.
AUSTRALIA, NEW ZEALAND AND INDONESIA
For chart showing isobars and fronts over New Zealand at
06:00 GMT, click here.
Low 976 mb at 54°S 168°E. Eastward-moving cold front
associated with this Low close to south-west corner of South
Island.
For chart showing isobars and fronts over Australia at 06:00
GMT, click here.
High 1021 mb just to the south of Adelaide. Ridge of high pressure
across Tasman Sea. Cold front from depression over the Southern Ocean
extends to south-west of Western Australia. Low 1009 over north coast
of Western Australia.
For 03:00 GMT visible satellite image, click here. For 03:00 GMT infra-red satellite image, click here.
These images show cold front cloud over southernmost part of New
Zealand. Also show the cold front cloud over the south-western corner
of Western Australia. Small cumulus clouds over Arnhem Land, eastern
Queensland and much of New South Wales. Most of Australia cloudless.
Blackness of the infra-red image indicates land surfaces and lower
troposphere hot. Cluster of cumulonimbus clouds south-east of New
Caledonia. Cumulonimbus clouds of the ITCZ across Indonesia, northern
Papua New Guinea and equatorial parts of Melanesia. ITCZ fairly weak
over Malaysia, Java and Sumatra. Very little cloud over Myanmar,
Thailand and Vietnam.
INDIA AND THE INDIAN OCEAN
For 08:00 GMT visible satellite image, click here. For 08:00 GMT infra-red satellite image, click here.
Most of the Indian sub-continent cloud-free. Area of medium and high
cloud over north-east India. Some cumulus activity over and off
southern tip of India. Arabian Peninsula and northern half of Arabian
Sea cloud-free. Cumulonimbus clouds along west coast of Sumatra. ITCZ
active across the Indian Ocean from Seychelles to Sumatra. Visible
image shows reflection of sunlight off the ocean surface near
5°S 65°E. Both images show Tropical Cyclone Hary, now at
32°S 62°E, south-east of Madagascar, and continuing to move
south-eastwards. Edge of snow-covered Antarctic continent can be seen
on both images.
AFRICA
For 06:00 GMT chart showing isobars and fronts over Africa
and adjacent oceans, click
here.
Cyclone Hary central pressure 998 mb. Low 1010 mb over Mozambique
Channel. Numerous depressions over Southern Ocean. Cold fronts from
two of them extend almost to South Africa. Ridge of high pressure
across South Africa with centres over Eastern Cape (1021 mb) and near
30°S 2°E (1019 mb).
For 12:00 GMT visible satellite image covering the whole of
Africa, click here.
For 12:00 GMT infra-red
satellite image covering the whole of Africa, click here.
Most of North Africa north of about 10°N cloud-free. The cloud that does exist is mostly high cloud. It appears white (cold) on the infra-red image and is very faint on the visible image. This visible image shows the surface features of North Africa very clearly (River Nile, sand dunes, Niger River, etc). Cumulus activity widespread over West Africa south of about 8°N, from Liberia to Nigeria. Zaïre River can be seen very clearly on visible image. Large area of cumulonimbus activity off Gabon (in the area 0° lat to 10°S, 0° long to 12°E). ITCZ fairly weak over the near-equatorial Atlantic Ocean. scattered cumulus and stratocumulus over the South Atlantic Ocean. Cumulus and cumulonimbus activity over Africa from equator to about 15°S also fairly weak. The large lakes of East Africa can be seen clearly on the visible image.
For 12:00 GMT visible image covering southern Africa south of about 15°S, click here. Many small cumulus clouds over Zambia, Botswana and Mozambique. Mostly clear skies over Zimbabwe, South Africa and southern Namibia.
EUROPE
For
06:00 GMT chart showing
isobars and fronts over the north-east Atlantic and most of
Europe, click here.
Very deep depression (961 mb) north-east of Newfoundland (54°N
50°W). Shallow Low (1011 mb) over the Plain of Hungary and
another Low (1015 mb) over the Ægean Sea. Pressure high over
northern Turkey (1020 mb) and over Morocco (1021 mb). Pressure low
over north-west Libya (1005 mb). Anticyclone (1035 mb) over southern
Norway. Weak cold front over northern Sweden. Weak warm front over
central Finland.
Depression with two centres to the west of Ushant (the north-west tip
of France). One centre 989 mb at 48°N 16°W; the other 993
mb at 50°N 7°W. Front from this weather system extending
eastwards across Wales and central England to Poland and Ukraine. The
bold curved lines over eastern France and Sardinia indicate bands of
cloud and rain.
For the 12:00 GMT visible satellite image, click here. For the 12:00 GMT infra-red satellite image, click here.
These images show that the bands over France and Sardinia moved
eastwards. The one that was over Sardinia at 06:00 GMT had reached
central Italy by 12:00 GMT.
The frontal cloud extending eastwards across the British Isles to
Ukraine can be seen clearly on the images. So, too, can the frontal
cloud associated with the Low near Newfoundland. The speckled area
north and south of the Azores indicates cumulus and cumulonimbus
activity in the polar maritime air that was flowing southwards behind
the Low centred west of Ushant. Cloud associated with the Low off
Ushant covered most of Spain and Portugal.
For the 13:04 GMT visible satellite image from Dundee
University, click
here. For the 13:04 GMT infra-red satellite image from Dundee
University, click
here.
Notice the clear skies in the anticyclone over Denmark, southern
Norway and the northern North Sea, but notice also the aircraft
condensation trails north of Shetland. The presence of persistent
contrails indicates that the upper troposphere was moist in these
areas. The visible image provides a superb view of the fjords and
snow-covered mountains of southern Norway.
Notice also on the images the wave clouds over Scotland, the north of
England and Northern Ireland. Waves form when air is lifted on the
upwind side of a mountain range and sinks the other side. A little
way downwind of the range, the air rises again and subsequently sinks
again. Thus, a train of waves extends downwind of the range. Clouds
form on the crests of the waves and take the form of parallel bands.
The clouds lie at right-angles to the wind. Notice that the waves
extend some distance downwind of the mountains where they originate.
On today’s 13:04 GMT visible image, wave clouds can be seen to
exist well out over the Atlantic. A question for the
students: what is the
distance between the wave crests, i.e. the wave length of the
waves?
For the 06:00 GMT chart of significant weather over Europe, click here. This shows strong easterly winds over the North Sea and a belt of precipitation extending across Europe from the British Isles to Russia. Showers occurred over Portugal and western parts of Spain. Mist and fog occurred over central and south-eastern Europe.
For a satellite image showing sea-ice, click here. This image, today’s 11:24 GMT visible image from Dundee University, shows that ice covered the northern half of the Gulf of Bothnia, the White Sea and adjacent sea areas. Lakes Ladoga and Onega (north-east of St Petersburg) can also be seen to be ice-covered.
NORTH AND SOUTH AMERICA
For a weather chart showing isobars and fronts over North America and much farther afield, click here. This extends across the North Pole to the coast of northern Russia. It also covers the northern half of the Pacific Ocean and much of the North Atlantic. The area of low pressure to the south-west of the British Isles can be seen (top right). So, too, can the deep depression off Newfoundland (centre right).
For the 09:00 GMT chart covering North America and the oceans to the east and west of North America, click here. This shows an anticyclone off the eastern seaboard of the USA (1021 mb) and another over the eastern Pacific (1039 mb). Fronts from a Low over Lake Michigan (1000 mb) brought cloud to the north-east and Mid-West of the USA. These fronts can be seen on the 15:00 GMT visible satellite image (which can be viewed by clicking here). Cloud amounts were generally small over western and south-western parts of the USA. The red figures on the weather chart are temperatures in degrees Fahrenheit. The green numbers are dew-point temperatures.
The 15:00 GMT satellite image shows that the ITCZ was active over northern parts of South America. Small cumulus clouds developed over much of Brazil. Skies were generally clear from about 20°S to about 33°S and frontal cloud was present over many parts of southern South America.
For today’s 00:00 GMT chart covering South America, the eastern Pacific Ocean and western parts of the South Atlantic Ocean, click here. This shows, like yesterday’s chart and the chart for the day before, that a Low was centred to the west of southern Chile. This is an occluding depression which has now developed two centres, one on the coast of Chile, the other near 47°S 83°W.
For Today’s Review of MetLink Observations, click here.
For Today’s Analysis, click here.
ACTIVITIES FOR PRIMARY SCHOOLS
Have you tried to make your own weather instruments? For guidance on making devices to measure wind speed, click here. For a host of practical ideas from the BBC, click here. For the Project Atmosphere Australia web guide to making simple weather instruments, click here. For the UK Met Office guide to making your own weather instruments, click here.
To return to Today’s Headlines, click here.
DOWNLOADING IMAGES FROM THE INTERNET
To download an image from the internet, you first right-click on the image. This opens up a dialogue box. You then (if you are using Internet Explorer) click on "Save Picture As" (or, in Netscape, "Save Image As"). This opens up another box which allows you to choose a name for the file, a folder (directory) to put it in and the type you wish the file to be. Click on "Save" and the image should now be saved in the folder you chose. You can now import the image into Word, PowerPoint, image processing software, etc.
To return to Today’s Headlines, click here.