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Weather report for primary schools for Wednesday 7 February 2001
THE HEADLINES TODAY
Perfect in Mexico. Drizzle in California. Hotter in Australia. Thunder in Kwazulu-Natal. Sunny again in Ethiopia. Dry in Madagascar. Hot and sunny on Ascension Island. Rain in Portugal. Showery in the British Isles. Warmer in Scandinavia.
THE WEATHER IN THE METLINK WORLD TODAY
The weather in Melbourne (Australia) is getting hotter. A maximum temperature of 31°C was recorded this morning at Trinity Grammar School and the sky was free of cloud. "Just getting hotter", said the students in their weather report. The maximum temperature recorded at Hilton College in Kwazulu-Natal (South Africa) was even higher than at Trinity Grammar School, 33°C, but the weather there was windy (33 km/h) and the sky rather cloudy. Indeed, the weather report from the school mentions thunder and lightning. A maximum temperature of 31°C was also recorded at Springdales School in New Delhi (India) and the weather was reported to be "hot and humid with no winds". Yet another place with a maximum temperature of 31°C was Puerto Vallarta in Mexico, where the weather appeared to be perfect. There wasn’t a cloud in the sky and the wind was calm. Micklefield School near Cape Town (South Africa) had a maximum temperature of 28°C. The weather there was quite cloudy (seven oktas of cloud) and quite breezy (24 km/h).
In the parts of the tropics that are warm and humid at this time of year, conditions were generally cloudy with rain or drizzle. At Jakarta, where the temperature was 22.5°C when the observation was made, the sky was overcast and the weather "muggy" (to quote the students). In Bulawayo (Zimbabwe), the weather was cool (18°C), overcast and damp this morning, and a rainfall amount of 23 mm was measured. At Marondera (also in Zimbabwe), the weather was improving after earlier rain. The temperature was 20°C this morning and a rainfall amount of 3 mm was measured. At Antananarivo (Madagascar), by way of contrast, there was fine weather, with a temperature of 26.0°C when the students made their observation. There was a light breeze and no sign of rain. "Warm and humid", said the students.
The weather at Two Boats School on Ascension Island was, in the words of the students, "hot and sunny". The temperature was 28°C around mid-day, with three oktas of cumulus cloud. In the trade-wind zone of the North Pacific Ocean, the weather at Leilehua High School on Oahu (Hawaii) seems to have been very pleasant. The temperature there was 24.0°C at 1300 Local Time (2300 UTC) and the lightest of breezes was blowing from the north-east. The cloud amount was small (only two oktas), made up of a few cumulus clouds and some thin cirrus cloud.
Central and eastern parts of the Mediterranean had a sunny day today. Otherwise, skies were rather cloudy over Europe today. Portugal’s Escola Secundária Gabriel Pereira in Evora was the wettest place in the MetLink world, with a rainfall amount of 64.4 mm measured. Rain fell in Madrid, too, the amount measured at Vicálvaro Primary School being 8.1 mm. The front that brought the rain to these two schools did not reach the other MetLink school in Spain, IES Vidal i Barraquer in Tarragona, but the weather there was rather cloudy and humid (98% relative humidity).
In northern Italy, Strasbourg and Versoix (Switzerland), the weather was also rather cloudy, but it was dry and mild. The temperature reached 15.5°C in Strasbourg, 21.5°C at the Collège du Léman in Versoix and 10°C in northern Italy. At Prague in the Czech Republic, the temperature was 9°C this morning and the weather sunny with a light breeze. The mild weather was brought by winds from the south-west.
Only over the most northerly parts of Europe were winds not from the south-west today, so the weather was mild as far north as central Scotland, southern Sweden and southern Finland. Fronts brought rain and drizzle and large amounts of cloud to many of the MetLink schools between 50° and 60°N. The weather was showery over most parts of the British Isles, with 40 mm of rain measured at Lytchett Minster Secondary School in Dorset (southern England), 12 mm on the Isle of Bute (Scotland), 8 mm at Bedales School in Hampshire (southern England) and lesser amounts at other schools in the British Isles. A rainbow was observed at St Oswald’s Primary School, Sheffield. Temperatures exceeded 10°C at many places in the British Isles but remained low, just above 0°C, in northern Scotland, where more snow fell.
Rain at Bor School (southern Sweden) melted the snow that had fallen in the past few days, but the precipitation that occurred at Mikkeli and Jyväskylä (Finland) today was again snow. Temperatures at these two schools in Finland were, however, very much higher than of late, being 2°C at Mikkeli and +0.7°c at Jyväskylä when the students made their observations. The weather at Vörå was cloudy this morning and the temperature still well below 0°C, being —7.3°C when the students made their observation. At Longyearbyen on Spitsbergen, the weather was colder than it has been recently, with a temperature of —7.1°C at 1030 UTC.
The weather was cold in Edmonton (Canada) today, where the sky was overcast and the temperature —12.0°C at 1600 UTC (0900 Local Time). The temperature was considerably higher but still below 0°C at the other MetLink school in Canada, where the temperature was —2.0°C at 1630 UTC (1130 Local Time). At least the weather was dry today at Breslau (near Toronto). It has been very unpleasant there in recent days. The temperature was close to 0°C in Ohio, too, at Forest Hill Parkway Academy, Cleveland. Though the weather was quite cloudy there, it was at least dry at last. At Moses Lake in Washington State, the temperature was —2.8°C at 1800 UTC (1000 Local Time) with a cloudless sky. Conditions were somewhat different in California, where, at Pasadena, the temperature was only 11.2°C at 2251 UTC (1451 Local Time) and light drizzle was falling. What has happened to the sunny, warm weather they have had recently?
Where would you like to have been during MetLinkInternational? Please tell us.
NOTES
There is material for teachers and pupils in primary schools on the Education pages of the United Kingdom’s Met Office. To go to the Education home page, click here. To go to the Curriculum Learning Centre, click here.
There is a great deal of material suitable for primary schools on the website of the BBC Weather Centre. For the basics of weather, things to do, weather games, stunning weather photographs and much more, visit the Weatherwise, Fact Files, Do-it-yourself (DIY) Weather and Weather Games pages. The Education Officer of the Royal Meteorological Society helped develop these pages.
For a wealth of information about the weather, including the current weather in the USA, visit the website of USA TODAY.
To read news stories sent in by MetLink schools, click here. For pictures of MetLink activities, click here.
At Adventdalen on Spitsbergen, 4 km from Longyearbyen, there is an automatic weather station that provides readings of temperature, wind speed, wind direction and barometric pressure. The webpage that shows these readings is updated every five minutes.
Do you want to find climatic statistics? If so, visit the Royal Meteorological Society’s Climate on the web site.
Do you want to find weather charts, satellite images or current weather data? If so, visit the Royal Meteorological Society’s Weather on the Web site.
Weather report for secondary schools for Wednesday 7 February 2001
PLEASE READ THIS REPORT FOR SECONDARY SCHOOLS IN CONJUNCTION WITH TODAY’S REPORT FOR PRIMARY SCHOOLS
ANALYSIS OF TODAY’S WEATHER IN THE METLINK WORLD
EUROPE
The dominant weather influence over the British Isles today was a complex depression. The Low that was over the northern part of Ireland yesterday afternoon continued to move north-eastwards and fill. At 0000 UTC, its position was 56°N 5°W and its central pressure was 972 mb. By 0600 UTC, it was on the Greenwich meridian at 59°N and its central pressure was 973 mb. At 1200 UTC, its position was 61°N 4°E and its central pressure 974 mb.
This Low’s partner, which was south-west of Ireland yesterday, moved southwards at first, to 45°N 19°W by 0000 UTC, when its central pressure was 986 mb. It then drifted north-eastwards a little, to reach 48°N 16°W by 0600 UTC, when its central pressure was 985 mb. Six hours later, its position was 49°N 13°W and its central pressure 989 mb. Meanwhile, another centre of low pressure formed within the complex depression, its position being 43°N 14°W at 1200 UTC and its central pressure then 993 mb. By 1200 UTC, the depression had four centres, the fourth being at 63°N 27°E (over Finland), its central pressure 996 mb.
Winds were from a northerly point on the western flanks of this complex depression, all the way from about 75°N 10°W to about 40°N 20°W. In this northerly flow, there was cumulus and cumulonimbus activity, as today’s satellite images show. To see one of these images, click here. The areas of the images containing cumulus and cumulonimbus clouds are those speckled with white or grey. Such clouds are manifestations of convection, and their formation over the Atlantic today resulted from the southward passage of cold air over a progressively warmer sea. The tallest clouds, which have the coldest tops, are whitest. Close inspection of satellite images shows that cumulus and cumulonimbus clouds tend to be organized in cells that are roughly hexagonal. On a day of cumulonimbus activity, you may notice that you have a few showers in quick succession and then have a period of quite sunny weather before showers return. This reflects the occurrence of convection clouds in groups, with quite large areas of fine weather between them. Have you noticed that the temperature can vary quite a lot as cumulonimbus clouds pass over you? The air is coldest where gusty downdrafts of cold air from within the clouds reach the ground.
On the eastern flanks of the complex depression, from Spain to Scandinavia, there were south-westerly winds today, bringing mild weather to most parts of western and central Europe and considerably warmer weather than of late to the MetLink schools in southern Sweden and southern Finland. South-easterly winds on the north side of the complex depression brought colder weather than of late to Spitsbergen, the temperature at Longyearbyen School this morning being —7.1°C. A cold front from the Low over Finland trailed south-westwards over Lithuania, Poland, Germany, France, Spain and the Canary Islands, bringing cloud and rain with it. A number of waves developed on the front, as today’s weather charts and satellite images showed. For the 0000 UTC chart, click here. For a satellite image, click here. The cold front that reached the Canary Islands appears to have turned westwards at about 30°N 20°W and linked up with a depression to the west of the Azores. For a satellite image that shows this, click here. The polar maritime air from the Arctic appears to have reached Madeira today.
The occluded front of the Low over Finland brought snow to two of the three MetLink schools in Finland, those at Mikkeli and Jyväskylä. The occluded front of the Low over the northern part of the North Sea brought rain to Bor School, near Värnamo, Sweden. Showers of rain (from cumulonimbus clouds) occurred at many places in England, Wales, Ireland and southern Scotland today, and snow fell again in the north of Scotland. Light rain fell in Madrid but not in Tarragona, Strasbourg, Versoix, Prague, Bozen or Udine, which all lay to the east of the cold front. The weather was overcast or rather cloudy at all of these places to the east of the cold front. As on previous days, pressure was high over North Africa and central parts of the Mediterranean Sea, with the highest pressure in this ridge about 1028 mb. From Algeria across Malta, Sardinia, southern Italy and Greece to the Black Sea, today was a sunny and warm day with light winds. Today was a good day to be on holiday in central and eastern parts of the Mediterranean.
AFRICA AND ASCENSION
Today’s satellite images show that skies were again clear over most of North Africa, apart from a few patches of cirrus and altocumulus cloud. At this time of year, as noted in the report for 6 February 2001, descending air in the Hadley Cell keeps the weather dry over almost the whole of North Africa. Today’s observation from the only MetLink school in North Africa, the International Community School at Addis Ababa, confirms that skies were clear over Ethiopia and the weather warm and dry. The ITCZ was again patchy and indistinct over the Atlantic Ocean today, with its activity confined to the latitude band 5°N to 3°S. Its influence does not appear to have extended as far south as Ascension Island, for the day there was hot and sunny with only three oktas of cumulus cloud.
Cumulonimbus activity was present over the parts of central and southern Africa that are currently experiencing their rainy season, and the intensity of this activity was greater than yesterday. Rain fell at both of the MetLink schools in Zimbabwe today, but the weather was dry and very pleasant at the MetLink school on Madagascar.
The MetLink schools in South Africa were unlucky today. Satellite images show that skies over southern Africa south of about 25°S were generally clear of cloud. However, the weather was cloudy at both schools, and the observation from Hilton College mentions thunder and lightning. Pressure was high today west of Cape Town (1025 mb at 38°S 0° Longitude) and also south-east of Port Elizabeth (1021 mb at 45°S 35°E). A trough of low pressure lay between them; and the tail end of a cold front from a depression close to Antarctica reached to Cape Town this morning, hence, in all probability, the cloudy weather that occurred at Micklefield School (for a satellite image that suggests this, click here). The reason for the thunder at lightning at Hilton College is not clear, but satellite images show that the southern edge of the cloud sheets affecting the northern half of southern Africa lay very close to this school.
To obtain the latest South African Weather Bureau chart showing fronts and isobars over southern Africa and the Southern Ocean, click here.
AUSTRALASIA
Satellite images show that cumulonimbus activity occurred today over northern parts of Western Australia and also over western and northern parts of Australia’s Northern Territory. They show, too, that the ITCZ again existed as a broad band of cumulus and cumulonimbus activity extending from about 75°E to about 160°E. Pressure was low (998 mb) over Western Australia south-east of Port Hedland. It was also low (999 mb) near Darwin and (999 mb) near 13°S 119°E. An anticyclone (1024 mb) centred midway between Tasmania and the North Island of New Zealand was the dominant influence over south-east Australia, with winds from the interior of Australia bringing warm weather to the Melbourne area. To obtain the latest chart of isobars and fronts over Australia, click here.
Again today, as on previous days, there was a northerly wind at Keio Girls’ High School in Tokyo. This was consistent with Tokyo being situated between the winter anticyclone over central Asia and an area of low pressure that extended across Kamchatka from about 50°N 175°E to about 55°N 145°E. Fronts associated with this complex depression brought cloud to most parts of Japan today To obtain a weather chart that includes Japan, click here. To obtain a chart containing Japan’s plotted weather observations, click here.
Satellite images of southern Asia show that skies were clear over the whole of India. The only significant amounts of cloud were patches of medium-level clouds over Sri Lanka and the southern tip of India. This is the season of the North-East Monsoon in southern Asia.
The effectiveness of the Himalayas at preventing cold air from reaching India can clearly be seen on infra-red satellite images at this time of year (for yesterday’s 1200 UTC image, click here). On an infra-red image: the darker the image, the hotter the radiating surface; the whiter the image the colder the surface. During the day, the Indian sub-continent is dark (because its surface is heated by the sun). The Tibetan Plateau is, at the same time, grey (where there is no cloud), as, too, are central and eastern parts of Asia. The air near the ground is very cold north of the Himalayas at this time of year.
NORTH AMERICA AND HAWAII
At 1200 UTC today, there was a Low of 986 mb over Newfoundland and another of 995 mb over the south-west of Utah. A High of 1040 mb was centred near 68°N 105°W (north-west of Hudson Bay) and a ridge of high pressure from it stretched south-eastwards to Florida. Another ridge stretched south-westwards across British Columbia to a High of 1038 mb at 40°N 140°W. A weak trough of low pressure brought some cumulus and cirrus-type cloud to Hawaii. The influence of the Low over the south-west of the USA can be seen in the weather at Pasadena, which was drizzly. The weather in Puerto Vallarta was, however, perfect, the dominant influence there being a subtropical anticyclone.
To obtain a recent weather chart from Environment Canada, click here and then choose the chart you require. For charts of North America made available by a German source, click here.
NOTES
Did you know that hourly measurements of wind, temperature, pressure and sea conditions recorded by the sensors of the automatic weather stations that are aboard data buoys on the North Sea and eastern North Atlantic are available on the web? To obtain the latest observations, click here. When the page has loaded, click on the yellow diamonds to obtain data for individual buoys. Please note that temperatures are by default given in degrees Fahrenheit, pressure in inches and winds in knots. For metric data, choose, on the page containing the data for the buoy you selected, ‘metric’ on the ‘Unit of measure’ drop-down menu and ‘Greenwich Mean Time (GMT)’ on the ‘Time Zone’ drop-down menu. Then press ‘Select’.
For satellite images of superb quality, click here and follow the links for the images you wish to see. From this website, maintained by the United Kingdom’s Met Office, you can obtain satellite images covering Europe, Africa, The Americas and Asia/Australasia.
For upper-air soundings made at stations in Europe, click here. For upper-air soundings made at stations in the USA, click here. For soundings from other regions, scroll down either the Europe page or the USA page and follow the appropriate links. Each sounding is provided in tabular form or as a Postscript file or as a GIF image.
To read news stories sent in by MetLink schools, click here. For pictures of MetLink activities, click here.
At Adventdalen on Spitsbergen, 4 km from Longyearbyen, there is an automatic weather station that provides readings of temperature, wind speed, wind direction and barometric pressure. The webpage that shows these readings is updated every five minutes.
Do you want to find climatic statistics? If so, visit the Royal Meteorological Society’s Climate on the web site.
Do you want to find weather charts, satellite images or current weather data? If so, visit the Royal Meteorological Society’s Weather on the Web site.
