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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
TODAY’S EXTREMES
Hottest: Banani International School, Lusaka, Zambia, 34°C
Coldest: James Gibbons School (Edmonton, Canada), -24.0°C
Windiest: Edgbaston High School for Girls (Birmingham, UK) and Pretoria Boys’ High School (South Africa), both 44 km/h
Driest: Pasadena City College, California, relative humidity 19%
Wettest: Jakarta International School (Indonesia), 135 mm of rain
FEATURE OF THE DAY
To find this feature, click here.
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 January, click here.
EASTERN AND SOUTHERN ASIA
A satisfied MetLink participant at Keio Girls’ High School in Japan today! "I like today’s weather", the reporter told us. Temperature 10°C at 10.12 am Local Time (01:12 GMT). Relative humidity only 36%. No cloud. No wind. Quite a contrast at Jakarta, where, at 7 am Local Time (00:00 GMT), the temperature was 24°C, the relative humidity 98% and the sky completely overcast (with stratocumulus cloud). Very wet during the past 24 hours. "Widespread flooding", the students reported. "Rain gauge overflowed". Rainfall amount 135 mm. Better weather at Singapore. "Fine and sunny all day" was the comment of the students. Only 2 oktas of cloud when the observation was made, at 2.30 pm Local Time (06:30 GMT). Temperature then 29.0°C and the wind Force 1 (from the north-east). A misty morning was followed by sunshine in New Delhi. Only one okta of cirrus cloud at 12.35 pm Local Time (07:05 GMT). Temperature then 17°C and the wind a very light north-easterly (Force 1). Maximum temperature 20°C. Minimum 5.5°C. "Chilly winds continue", the students reported.
AFRICA AND ASCENSION
"Hot and sunny with a light breeze", the students of Two Boats School on Ascension reported. Cloud cover 4 oktas of cumulus and cumulonimbus at 12.40 pm Local Time (12:40 GMT). Temperature then 26°C. Wind 15 km/h from the east. Maximum temperature 30°C. Minimum 18°C. Hot at Lusaka in Zambia, too, where, at the Banani International School at 10 am Local Time (08:00 GMT), the temperature was 28°C and the wind a light (Force 2) south-easterly. Maximum temperature 34°C. Cloud cover 5 oktas of cumulus.
"Fairly hot and sunny" at Kampala (Uganda), where, at 1 pm Local Time (10:00 GMT), the temperature was 24°C. Quite breezy, though, with a wind of Force 4 from the south-east. "Warming up", said the students of Kgaswe Primary School (Botswana), where the temperature at 10 am Local Time (08:00 GMT) was 30°C. Maximum temperature 32°C, minimum 21°C. "Rain of the last two days has gone", they reported. Cloud cover 3 oktas of cumulonimbus and wind from the north-east 9 km/h.
Plenty of rain at Highbury Preparatory School, Hillcrest, South Africa, where 21 mm fell in 30 minutes last night. Heavy rain at 7 am Local Time (05:00 GMT). Temperature then 22°C. Maximum temperature 27°C, minimum 21°C. Relative humidity 74%.
Rain of medium intensity at Pretoria this morning. Temperature at 10 am Local Time (08:00 GMT) 24.2°C and relative humidity 73%. Maximum temperature 24.2°C, minimum 20.1°C. Rainfall amount 13.97 mm. Several observations from Pretoria today: 08:00 GMT, 09:32 GMT, 11:20 GMT and 12:00 GMT. No precipitation at 09:32; slight rain at 11:32 and 12:00. Temperature 26.9°C at 09:32, 28.5°C at 11:20, 28.2°C at 12:00. The wind speed increased from calm at 08:00 to 3 km/h at 09:32 and 44 km/h at 11:20 before decreasing to 33 km/h at 12:00 GMT.
Sunny in Zimbabwe. A "hot morning probably getting hotter" at Peterhouse (Marondera). Calm with only one okta of cirrocumulus at 8 am Local Time (06:00 GMT). Temperature then 22.0°C, after a minimum of 21.3°C. Maximum temperature 26.6°C. Two oktas of altostratus cloud at Bulawayo (Christian Brothers’ College) at 7.30 am Local Time (05:30 GMT). Temperature then 22.5°C (almost the same as at Peterhouse) and relative humidity much the same (71% at Bulawayo, 72% at Marondera). Wind at Bulawayo north-easterly Force 1. Maximum temperature 31°C, minimum 18°C.
EUROPE
Dull and damp in most parts of the British Isles today. Still quite breezy but not as windy as it has been recently. The windiest place Edgbaston, where the wind strength this morning was Force 6 (44 km/h). "Grey, damp, chilly and windy" the comment from the Edgbaston students. This theme of dullness and dampness echoed from elsewhere. "Windy, dull, damp and dismal" from Radley College in Oxfordshire. "Dull (again!) with gusty winds and occasional light showers of rain" from the Medina Valley Field Centre on the Isle of Wight. "Penetratingly damp and grey" from the Richard Lander School in Truro (Cornwall). "Overcast and breezy with very light drizzle" from Norwich School. "Damp outlook" from the Royal Hospital School at Holbrook, Ipswich. "Slight drizzle; unpleasant to be outside" from St Patrick’s RC Primary School near Preston, Lancashire. "Dull and cloudy with a little drizzle" from Altrincham Girls’ Grammar School in Cheshire. "Drizzle expected soon" from Pitsford Hall Weather Station, Northampton. "Grey cloud cover; feels very cool; damp outlook" from St Oswald’s Primary School in Sheffield. "Mild, humid, gloomy" from Bradfield College in Berkshire. "Overcast and drizzle falling" at Bedford Modern School. "Miserable; cloud low on the hill; very gloomy" from Coed Cae Junior School at Blaina, (Blaenau Gwent). Overcast and "feeling damp" at Farr High School on the north coast of Scotland. "Dull and rainy" early in the day at Queensferry near Edinburgh, but "clear blue skies later". Some sun, too, at Portgordon Primary School in Morayshire this afternoon, where at 2 pm it was "warm and sunny with a slight breeze". For webcam pictures of places in the British Isles today, click here for Bristol, here for Leicester and here for Norwich.
Still mild in the British Isles today, with maximum temperatures today above 12°C in many places. Winds from a mild direction, from the west or south-west almost everywhere. "Mild but changeable" at the Malahide Community School in Dublin, where the temperature was 10°C at 9 am Local Time (09:00 GMT) and the wind from the south-west Force 3. Temperature 13.2°C at Wells Cathedral School in Somerset at 9 am this morning; maximum temperature 15.2°C, which is remarkably warm for late January. Even warmer at Belvue School in Northolt (west London), where the maximum temperature was 15.5°C.
Still cold in Scandinavia. Temperatures well below 0°C in Finland and several degrees below 0°C in Oslo (Norway), where the temperature at 12.10 pm Local Time (11:10 GMT) was —2.7°C and the sky completely overcast. In the words of the Oslo students: "The clouds look like it is going to snow". For a webcam picture of Oslo this morning, click here. Slight drizzle falling at Bor School in southern Sweden at 8 am Local Time (07:00 GMT). Maximum temperature at Bor +4.8°C, minimum —0.8°C.
The coldest place in Finland today was Vasa, where the minimum temperature was —17°C. Almost as cold at Mikkeli, where the minimum temperature was —16.5°C and the temperature at 10 am Local Time (08:00 GMT) still as low as -16.1°C. Maximum temperature —7.3°C at Mikkeli, -10°C at Vasa. Skies clear, though, at both places: with only one okta of cloud (cirrus) at Mikkeli and two oktas (cirrus) at Vasa. "A clear, frosty winter day", the Mikkeli students commented, with the additional remark: "getting cooler"! No comment on the weather today from Vörå, where the temperature at 1.10 pm Local Time (11:10 GMT) was —8.1°C. Maximum temperature —7.6°C, minimum —11.7°C. Cloud cover 6 oktas of altostratus. Wind calm. For a webcam view of snow on a road in Finland today, click here.
Warm again in Romania today. "A really warm day", the students at Constanta reported. Only 4 oktas of high cloud (cirrus and cirrostratus) at 3 pm Local Time (13:00 GMT). Temperature 15.1°C and the relative humidity only 49%. Quite breezy, though, with a wind of Force 4 from the north-east. Later in the afternoon, at 6 pm Local Time (16:00 GMT), cloudier at Constanta, with 8 oktas of stratocumulus reported from Carmen Sylva High School. Temperature then 11.8°C and the wind not as strong as earlier (Force 2 from the north-east). Still "pleasantly mild" in Strasbourg (eastern France), the observer reported. Maximum temperature yesterday 14°C. Temperature at 8.30 am Local Time today (07:30 GMT) only 6.0°C but higher later: 12.0°C at 1 pm and 5.30 pm. Calm, with the sky partly cloudy, mostly with high cloud and altocumulus.
"A wonderful spring day is coming", said the students of Bischöfliches Gymnasium St Ursula at Geilenkirchen in Germany. Calm with only one okta of cirrus cloud at 9.40 am Local Time (08:40 GMT). Temperature then 8.3°C. Maximum temperature 12.1°C. Sunny and warm in Malta, where the temperature at 10 am Local Time (09:00 GMT) was 16°C and the sky almost cloudless (one okta of cirrus). Wind a light south-westerly (9 km/h). For a webcam view of Malta today, click here.
Cold in the early morning but warm and dry later in Madrid, where the temperature was 4°C at 9.15 am Local Time (08:15 GMT), 15°C at 3.20 pm Local Time. Four oktas of cirrus cloud at the time of the morning observation, six oktas of stratus in the afternoon. Wind calm at both 8.15 am and 3.20 pm. Calm at Bozen at 3 pm Local Time (14:00 GMT) Temperature then 10°C and the cloud cover only 3 oktas of high cirrus. Relative humidity only 34%.
NORTH AMERICA
"Clear skies" over Raleigh (North Carolina), the students of Cardinal Gibbons High School reported. Quite warm again today, but not as warm as yesterday. Calm with a temperature of 15.0°C at 8.05 am Local Time (13:05 GMT). Very different at Aurora (Illinois), where at 1.05 pm Local Time (19:05 GMT) snow was falling, the wind blowing from the north-east with a speed of 24 km/h and the temperature —1°C. "We are expecting up to 10 inches of snow today and tomorrow", the students of the Frank Hall Elementary School reported. Very cold at Fernley in Nevada, where the temperature at 8.44 am Local Time (16:44 GMT) was -14°C. Calm, though, and no cloud.
"Cloudy, cool and calm" at Moses Lake, the students of Peninsula Elementary School in Washington State reported. Temperature at 11 am Local Time (19:00 GMT) 2.2°C and the cloud cover 7 oktas (stratocumulus, cumulus and cirrus). "Windy, cold and sunny" at Reseda (California), where the temperature was 9.4°C at 10.37 am Local Time (18:37 GMT). No cloud at the time and the wind then blowing from the north with a speed of 15 km/h. Relative humidity only 39%. Cool and sunny at Pasadena, too, where the temperature at 12.07 pm Local Time (20:07 GMT) was 14°C and the sky clear of cloud. Once again, the James Gibbons School in Edmonton (Alberta) was the coldest place in the MetLink world, with a minimum temperature of -24.0°C. At 9.30 am Local Time (16:30 GMT), the temperature was —16.0°C and the sky cloudless. "Mainly sunny", the students reported, and "predicted to get warmer tonight". We shall look at the observations with interest tomorrow to see if that prediction proves correct! And will the weather soon become warmer in California?
TODAY’S ANALYSIS
For today’s Feature of the Day, click here.
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 show as white areas. Medium-level clouds and very cold land areas show as grey. For information about obtaining satellite images of the highest quality, see the notes section below.
For the history of the Beaufort Scale of Wind Force and guidance on how to interpret weather charts, go also to the Notes section.
The observations made in Japan at 06:00 GMT today (3 pm Local Time) show that winds were from the west over the islands of Kyushu and Shikoku and over the southern half of Honshu. They were rather light and variable over Hokkaido and the northern part of Honshu. Skies were partly cloudy over most parts of Japan today, with cloud amounts generally small in the Tokyo area.
Today’s 06:00 GMT satellite image from Wisconsin shows that the most active parts of the ITCZ were today those over the eastern half of the Indian Ocean, Indonesia and the western part of the Pacific. As usual at this time of year, the axis of the ITCZ lay a few degrees south of the equator in most parts of the eastern hemisphere. The ITCZ was particularly active today over Jakarta, but Singapore enjoyed a fine, sunny day. Indeed, January and February are the wettest months of the year in Jakarta. Which are the wettest in Singapore and Medan (and why)? To find the climatic data you need to answer this question, click here for Medan and here for Singapore.
Today’s 00:00 GMT chart of winds at a height of 850 mb (roughly 1500 m) over southern Asia and the Indian Ocean shows that winds over the Arabian Sea and north-west India were from the north-east, which is typical of this time of year, when the dominant influence is the so-called ‘north-east monsoon’. In actual fact, this is not really a monsoon. The winds are part of the Hadley Circulation, which breaks down in summer to give the south-west monsoon. Air sinks over India in winter and north-easterly trade winds blow over southern Asia towards the ITCZ. The winds at New Delhi were from the north-east at 12.05 pm Local Time, and skies were largely cloudfree. Satellite images show that skies were almost cloudless over most parts of the Indian subcontinent, which is consistent with air sinking.
Today’s 06:00 GMT weather chart for Australia and adjacent regions shows that barometric pressure was low over most of Australia and the Coral Sea, with pressure high over the Great Australian Bight. Pressure was also high to the west of Perth and over New Zealand. From today’s satellite image, the front to the south of Tasmania appears to be fairly weak. This image shows a few scattered cumulonimbus clouds near Townsville and south-west of the Gulf of Carpentaria.
AFRICA
Today’s 06:00 GMT weather chart for southern Africa and adjacent oceans shows that pressure was low near Durban and southern Madagascar, with the rainy weather at the schools in Hillcrest and Pretoria consistent with there being a Low near Durban. Pressure high to the south-west of Cape Town and near Kerguelen. Once again, there were many vigorous depressions over the Southern Ocean in the so-called ‘Roaring Forties’ and ‘Furious Fifties’. As on previous days, a ridge of high pressure extended northwards over the South Atlantic as far as Ascension Island. The satellite image for 06:00 GMT shows that the ITCZ was most active over Africa between the equator and about 15°S. of South Africa. Sinking air in the Hadley Circulation maintained clear skies over most parts of North Africa.
EUROPE
Today’s 06:00 GMT infra-red satellite image shows an abundance of cloud over the British Isles and other parts of western Europe. The weather chart for 06:00 GMT shows the fronts with which this cloud was associated. With pressure low over the North Atlantic from Shetland to southern Greenland, winds were south-westerly over all parts of the British Isles and over France. Fronts associated with weak areas of low pressure brought precipitation to southern Scandinavia, the southern Baltic and the countries immediately to the east of the southern Baltic. Winds from a northerly point brought cold air to Finland. High pressure was again today the dominant influence over southern Europe and the Mediterranean, and this is consistent with the observations of fine weather received from MetLink schools. For temperatures and significant weather over Europe at 06:00 GMT today, click here. The weather was again misty or foggy over many parts of southern Europe and North Africa. This was most likely radiation fog, which occurs when skies are clear at night and winds light. For a feature which focuses upon radiation fog, click here.
More stormy weather is forecast for the British Isles for later in the week. For information about one of the most damaging storms to strike the United Kingdom in recent times, namely The Great Storm of 1987, click here. For a feature on the storms that brought havoc to the British Isles in October 2000, click here. This feature contains exercises that are intended for school use.
NORTH AMERICA
For a summary of today’s weather over North America, click here. This chart shows that air was very cold over most of Canada, warm over southern and south-eastern states of the USA. A front running from Nova Scotia to northern Texas was accompanied by precipitation. This precipitation was snow in many places, including Illinois, where snow was falling at mid-day. This front can be seen very clearly on the visible satellite image for 18:00 GMT. Indeed, the front extended much farther south-westwards than was indicated on the weather chart. The ice and snow on Hudson Bay can clearly be seen on this satellite image. The image also shows that skies were clear over most parts of California and Nevada, but the weather remained cool, with the winds mainly from a northerly direction. For a weather chart showing isobars and observations over Canada and northern parts of the USA at 00:00 GMT, click here. For a weather chart showing isobars and observations over the whole of North America at 00:00 GMT, click here.
FEATURE OF THE DAY
For Today’s Review of MetLink Observations, click here.
For Today’s Analysis, click here.
To return to the analysis for Europe, click here.
CUMULUS CLOUDS AND COASTAL FOG
The picture shows a view south over Poolewe, western Scotland, UK. It was taken at 14:00 GMT on 10 June 1963 and shows something unusual. It shows coastal fog coexisting with cumulus clouds.
For several days, an anticyclone had been centred near Iceland, giving sunny days and very light north-easterly winds over Scotland. At low levels, air had travelled to western Scotland from well to the north of the Shetland Islands. In this air’s source region, the temperature of the sea’s surface was about 10°C. As the air travelled southwards, it was moistened considerably.
Radiation cooling into the clear skies of the anticyclone favoured fog formation at night over the moister part of the land, but the sun dispersed the fog rapidly by day, except on the coast, where it persisted until early evening. An increase in fog depth occurred over Loch Maree (left-hand side of the picture). The flow of the cool air that maintained the fog was disturbed by a small island (Isle of Ewe), thus causing the water on the bottom right of the picture to be clear of fog.
Cumulus clouds began to form over Beinn Eighe (1009 m) and Beinn Alligin (985 m) around 10:00 GMT, when the sun had warmed the slopes sufficiently. Examination of the 12:00 GMT upper-air temperature and humidity profiles measured at Stornoway (a meteorological station roughly 100 km north-west of Poolewe), shows that a temperature of about 22°C was necessary on the slopes to start cumulus convection. Until this temperature was reached, air over the hillsides did not become warm enough to penetrate the anticyclone’s inversion of temperature. Over the sea, where there was virtually no heating of the low-level air, the inversion persisted. The temperature of the sea varies little between day and night, even on the sunniest of days. In contrast to land surfaces, water heats up very slowly. The reasons are that (a) water has a large thermal capacity (b) water moves around, whereas land does not (c) water evaporates (d) sunlight penetrates much farther into water than into the surface of land.
For Today’s Review of MetLink Observations, click here.
For Today’s Analysis, click here.
To return to the analysis for Europe, click here.
NOTES
You can obtain satellite images of the highest quality from the Dundee Satellite Receiving Station, Dundee University, Scotland. For further information, see the ‘Notes’ sections of the MetLink weather reports for 22 and 23 January.
To return to Today’s Analysis, click here.
THE BEAUFORT SCALE OF WIND FORCE
If you want to learn about the history of the Beaufort Scale of Wind Force, click here. If you don’t know where on the web to find the scale for land observers, click here.
To return to Today’s Analysis, click here.
INTERPRETATION OF WEATHER CHARTS
For guidance on how to interpret weather charts, click here.
To return to Today’s Analysis, click here.