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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: Medan International School (Sumatra, Indonesia) and Banani International School (Lusaka, Zambia), both 33°C
Coldest: James Gibbons School (Edmonton, Canada), -23.0°C
Windiest: Portgordon Primary School (Morayshire, Scotland), 44 km/h
Driest: Pasadena City College, California, USA, relative humidity 40%
Wettest: Jakarta International School (Indonesia), 67.5 mm of rain
FEATURE OF THE DAY
A METLINK SAFARI
To find this feature, which is mainly for primary schools, 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
"Very wet" with "lots of local flooding" in Jakarta (Indonesia), where slight rain was falling at 7 am Local Time (00:00 GMT) and the temperature then 24°C. Overcast and calm and a relative humidity of 99%. Maximum temperature 30°C and the minimum 23°C. Similar at Medan (Sumatra), where, at 8 am Local Time (also 00:00 GMT), the temperature was 25°C, the wind calm and the sky completely overcast. No rain falling, though, and none measured. Relative humidity 69%. Maximum temperature 33.0°C. Minimum 24.0°C. "Mainly sunny and hot" at Singapore, where, at 2.30 pm Local Time (06:30 GMT), the temperature was 27.0°C, the wind a light northerly (only 3 km/h) and the cloud cover 4 oktas of cumulus. A "misty morning" and a "sunny afternoon" at New Delhi, where, at 12.34 pm Local Time (07:04 GMT), the temperature was 19°C and the cloud amount only 2 oktas (of cirrostratus). Maximum temperature 20°C. Minimum a chilly 6°C.
AFRICA AND ASCENSION
Five oktas of cumulus and cumulonimbus cloud at Two Boats School (Ascension) at 2 pm Local Time (14:00 GMT). Temperature then 26°C and the relative humidity 65%. Wind 15 km/h westerly. Drizzle of medium intensity falling at Kampala at 1 pm Local Time (10:00 GMT). Temperature then 20°C and the wind blowing at 24 km/h from the north. The sky completely overcast with cumulonimbus and cirrus cloud.
Only 3 oktas of cloud (stratocumulus) at the Banani International School in Lusaka, Zambia, where, at 12 noon Local Time (10:00 GMT), the temperature was 26°C and the wind a light south-easterly (3 km/h). Maximum temperature 33°C. Minimum 21°C. Also 3 oktas of cloud (cirrus and stratocumulus) at Peterhouse (Marondera, Zimbabwe). There, at 8 am Local Time (06:00 GMT), the temperature was 21.2°C and the relative humidity 77%. Rainfall amount 20 mm. Maximum temperature 26.8°C. Minimum 20.4°C. "Patchy rain mid-afternoon" at Bulawayo (Zimbabwe) and slight rain falling at 7.30 am Local Time (05:30 GMT). Temperature then 22°C and the cloud amount only 2 oktas. Rainfall amount 0.05 mm. Maximum temperature 31°C. Minimum 18°C. No wind.
Warm and fairly cloudy at Highbury Preparatory School (Hillcrest, South Africa). Temperature at 7 am Local Time (05:00 GMT) 21°C and the lightest of breezes (3 km/h) blowing from the north-east. Relative humidity then 82%. Maximum temperature 26°C. Minimum 19°C. A "cloudburst for about ten minutes" at the Pretoria Boys’ High School in South Africa. Heavy rain falling from cumulonimbus cloud at 2.30 pm Local Time (12:30 GMT). Temperature then 25.6°C. Maximum temperature 29.8°C. Minimum 18.9°C. Rainfall amount 12.0 mm. Slight drizzle at Pretoria at 10 am Local Time. Temperature then 26.6°C and the cloud cover only 3 oktas (stratus). Rainfall amount measured at that time 8.33 mm. Thus, the 12 mm had fallen in only 4_ hours.
EUROPE
The weather system that brought gales and heavy rain to the British Isles yesterday brought strong winds and heavy precipitation to southern Scandinavia and northern Germany overnight. "Storm over southern Sweden", the students of Bor School (Sweden) reported; "100,000 households lacking electric power". Medium rain falling at Bor at 8 am Local Time (07:00 GMT). Temperature then +2.1°C and the wind 24 km/h from the west. Cloud amount 6 oktas of stratus. Maximum temperature 5.5°C. Minimum +0.4°C. "Clear and sunny and windy and a lot of snow on the ground" at the Oslo International School in southern Norway, with a temperature of -0.5°C at 12.22 am Local Time (11:22 GMT). Wind then 33 km/h from the north-west. Maximum temperature +1.4°C. Minimum —1.9°C.
Completely overcast and snow falling at Vörå (Finland)at 1 10 pm Local Time (11.10 GMT). Wind from the north (9 km/h) and the temperature—7.7°C. Maximum temperature —5.9°C. Minimum —10.3°C. Snow falling at Mikkeli, too, where, at 10 am Local Time (08:00 GMT), the temperature was —8.4°C and the wind a very light south-westerly (3 km/h). Maximum temperature —6.1°C. Minimum —10.0°C. "PE lessons: Skiing, skating …", the students reported! Very nice, too. Some of us are envious! Slight snow falling at Vasa at 9.44 am Local Time (07:44 GMT). Sky then overcast and the temperature —4.5°C. Maximum temperature +3.3°C and the minimum -4.5°C. Colder at Vasa at 7.03 pm Local Time, when the temperature was —8.0°C. Still overcast and slight snow still falling. Wind now from the north, as at Vörå. "Cloudy, chilly weather" at Jyväskylä but no snow falling at the time of the observation (1.40 pm Local Time). Temperature then —7.9°C, the cloud amount 7 oktas (altostratus) and the wind westerly 15 km/h. Maximum temperature —7.9°C. Minimum —8.9°C.
In the British Isles, today was a day to clear up after the gales and heavy rain of yesterday. Still quite windy, though, with 44 km/h at Portgordon Primary School in Morayshire and 33 km/h at several schools (Richard Lander School in Truro, St Patrick’s Primary School near Preston and Milford Haven School in Pembrokeshire). Heavy showers at George Watson’s College, Edinburgh, where, at 2 pm, a westerly wind of 24 km/h was blowing and the temperature was 8.0°C. Showers, too, at Queensferry Primary School near Edinburgh, where the temperature at 4.23 pm was 7.2°C. "Wet snow changing to rain" at Lionel School on the Isle of Lewis, where, at 1.20 pm, the sky was completely overcast, medium rain falling and the temperature only +2°C. In the south of England, slight drizzle was falling at Westbourne House School near Chichester at 10.30 am and also at The Royal School in Hampstead, London, at 12.50 pm. At Westbourne House, the temperature was 10.7°C and at The Royal School it was 11°C. Mild indeed for late January, as the students of Malahide Community School in Dublin commented. And the students of Radley College in Oxfordshire also mentioned that the weather was mild. The temperature there was 7°C at 8.30 am but had reached a maximum of 11°C in the previous 24 hours. As at Radley, where the cloud amount was only one okta at 8.30 am, the day began bright and clear in many places, among them Bromsgrove in Worcestershire, where the cloud amount was only 2 oktas (of cumulus) at 8.30 am. By 1 pm, the weather had become cloudy in many places, one of them Alleyne’s High School at Stone in Staffordshire, where, at 1 pm, slight rain was falling.
"A beautiful sunny and very mild spring-like day" at Strasbourg in France. The observer said he had "no complaints"! Three observations made today: at 8.30 am Local Time (07:30 GMT), 1 pm and 5 pm. Cloud amount 3 oktas each time. Contrails and rose-tinted clouds at 8.30 am. Maximum temperature 14.0°C. Minimum 7.0°C.
"Long contrails visible" at Bozen in northern Italy at 4 pm Local Time (15:00 GMT). Cloud amount then 3 oktas (cirrus and altocumulus). No cloud at all at Bozen at 10 am and 10.30 pm Local Time. The wind was light at Bozen today (9 km/h at 10 am, 3 km/h at 4 pm and calm at 10.30 pm) and the maximum temperature was 13°C. Last night’s minimum was -1°C.
A very sunny day on Malta, where the only cloud at 10 am Local Time (09:00 GMT) was cirrus (4 oktas). Was most of this produced by aircraft, too? Temperature at 10 am 15°C. Maximum 16°C. Sounds very pleasant, but the day was quite windy (24 km/h at 10 am). "Sunny and cold" was the report from Madrid at 9.15 am Local Time (08:15 GMT), when the temperature was 5°C. "A typical spring day" was the report from Madrid at 3.20 pm Local Time, when the temperature was 15°C and the sun still shining.
A cloudy morning in Constanta (Romania), followed by a sunny afternoon. temperature only 4.3°C at 8 am Local Time (06:00 GMT) but had risen to 9.5°C by 12 noon Local Time and 10.7°C by 3 pm.
NORTH AMERICA
The first observation received from North America today was that made at Cardinal Gibbons High School in Raleigh (North Carolina) at 8 am Local Time (13:00 GMT). "A beautiful morning with mostly sunny skies", the students reported. Temperature 12°C. Just a trace of cirrus cloud. Wind from the north-west 3km/h. Maximum temperature 14°C. Minimum 10°C. Sounds very pleasant. The next observation received from North America quite a contrast. Temperature at James Gibbons School in Edmonton (Alberta) at 9.30 am Local Time (16:30 GMT) —22.0°C! Sunny, though, with a light wind (SW, 3 km/h). Maximum temperature —14°C. Minimum -23.0°C. Next to arrive, the observation from Moses Lake in Washington State, where, at 11 am Local Time (19:00 GMT), the temperature was —2.8°C and the sky fairly cloudy (6 oktas of cirrus, altocumulus and stratus). Wind very light (SE, 3 km/h).
Weather still cool in California. Sunny, though, at Cantara Street Elementary School in Reseda, where, at 10.38 am Local Time (18:38 GMT), the temperature was 8.1°C, which was quite an improvement on the minimum of —0.9°C. More rain expected by the students at Pasadena, where the cloud amount at 12.25 pm Local Time (20:25 GMT) was 5 oktas (nimbostratus and cumulus) and the wind was blowing from the south-west with a speed of 15 km/h. Only 10°C and fairly cloudy (6 oktas of cumulus cloud) at Livermore at 3 pm Local Time (21:00 GMT). Minimum temperature only +1°C. Maximum 10°C.
TODAY’S ANALYSIS
NB 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.
AUSTRALASIA
As today’s visible
satellite image for 03:00 GMT
shows, the vigorous depression that brought severe weather to Japan
over the weekend has moved to the Aleutian Islands. Cool westerly
winds flowed across Japan today. This 03:00 GMT image and the
satellite
image from Wisconsin show
that the ITCZ was not quite as active over south-east Asia and
Indonesia as on previous days. Nevertheless, it was quite active in
some places, such as Jakarta, where 67.5 mm of rain fell.
Today’s weather
chart for Australia and
adjacent regions shows that barometric pressure was low over northern
Australia and the Coral Sea. It was high over the Indian Ocean west
of Perth (1022 mb) and also near Tasmania (1019 mb). The fronts to
the south of the Great Australian Bight can be seen on satellite
images and so, too, can a few
monsoonal cumulonimbus outbreaks over the Arafura Sea and the waters
of the Joseph Bonaparte Gulf west of Darwin.
AFRICA
Barometric pressure was low today off Cape Town and Port Elizabeth (two centres of low pressure, each 1006 mb). It was low, too, over Madagascar (1014 mb). Pressure was high to the north-east of Gough Island (1021 mb) and also near Crozet Island (1029 mb). There were many vigorous depressions over the Southern Ocean. A ridge of high pressure extended northwards over the South Atlantic as far as Ascension Island. Visible and infra-red satellite images show that the ITCZ was near the equator over the Atlantic Ocean today but very patchy. These images show vigorous cumulonimbus activity today over the Congo, north-east Zambia, Tanzania and eastern parts of South Africa. The activity between the equator and about 15°S was associated with the ITCZ. The activity over eastern South Africa was associated with a trough of low pressure that ran northwards from the depression off Port Elizabeth. In this trough, surface winds were very light and surface temperatures high. At the same time, surface air was very humid. Day-time heating probably released conditional instability, thus triggering the cumulonimbus activity.
EUROPE
Today’s weather chart for 06:00 GMT shows a depression of 972 mb over the Baltic Sea, near Åland. This is the depression that brought the gales and heavy rain to the British Isles yesterday. The depression filled significantly during its passage eastwards. Nevertheless, it was still vigorous enough to bring down power lines in southern Sweden. The chart of temperatures, isobars and significant weather for 06:00 GMT today shows that winds were strong at that time over the southern Baltic, Denmark and southern Sweden. It also shows that snow was falling over central Sweden and rain was falling over Estonia, Latvia, Lithuania and Belarus. As the fronts of the depression moved eastwards overnight, they brought heavy rain that caused flooding in northern Germany and northern Poland.
The winds that were blowing across the British Isles today were south-westerlies in most places, south-easterlies over northern Scotland. Using Buys Ballot’s Law, which states that (in the northern hemisphere) low pressure lies to the left of you if you stand with your back to the wind, we can deduce that low pressure lay to the west of northern Scotland. Inspection of the weather chart for 06:00 GMT confirms this. A Low of 981 mb was centred at 56°N 30°W, with a warm front from it bringing precipitation to northern Scotland.
High pressure was the dominant influence over southern Europe and the Mediterranean, and this is consistent with the observations of fine weather received from MetLink schools. As often happens in quiet anticyclonic conditions, mist formed widely over southern Europe. Fog also formed over the Ligurian Sea, Po Valley and northern Adriatic, as can be seen on today’s visible satellite image for 12:00 GMT. We can see that this cloud is at a low level because it appears a very light grey on the infra-red satellite image for 12:00 GMT. The reason for the fog is not obvious, but the weather chart shows a weak cold front over the area in question.
To obtain the latest information about flood watches and flood warnings in Great Britain, click here for England and Wales (from the Environment Agency), here for Scotland (from the Scottish Environment Protection Agency).
NORTH AMERICA
Today’s weather charts (click here and here) show that pressure was high over Winnipeg (1033 mb) and over central parts of the North Atlantic (1027 mb). Pressure was low over the Aleutian Islands (985 mb), Alberta (1016 mb) and Colorado (1003 mb). Light south-westerly winds fed mild air across the south-east of the USA and a broad flow of cool air from the north brought below-average temperatures to Alberta and the western states of the USA. Today’s visible satellite image for 18:00 GMT shows a frontal band of cloud running south-westwards from the Great Lakes to Baja California and beyond. It also shows an extensive area of cumulus and cumulonimbus activity over the eastern North Pacific, where cold air was passing over warmer water and thus being heated from below to become convectively unstable. Today’s chart of sea-surface temperatures shows that the water temperature was about 10°C west of Oregon, 15-17°C west of San Diego. As one of today’s weather charts shows, air temperatures over the sea west of Oregon and northern California were about 7°C.
Notice on the satellite image Lake Okeechobee in Florida. Notice also the ITCZ activity over the eastern Pacific between the equator and 10°N, as well as the comparative inactivity of the summer rain systems over South America. The sun’s reflection off the sea can clearly be seen near 10°S off the coast of Peru.
FEATURE OF THE DAY
To return to Today’s Review of MetLink Observations, click here.
To return to Today’s Analysis, click here.
A METLINK SAFARI
What do the MetLink webcam pictures show you? To find out, let’s go on A MetLink Safari, a tour of the MetLink world.
Many MetLink students have never seen snow, so let’s begin in a part of the world that is snowy at this time of year. Click here for a view of US Interstate Highway 90 at Snoqualmie Pass in Washington State on 23 January 2002. When this picture was taken, oversized vehicles were prohibited because of the snow. Click here for another view of the Pass, taken the following day (24 January). Click here for a view of the Pass today.
Click here for another picture of a snow-covered road, this one in Finland, near Lappeenranta in south-eastern Finland, near the border with Russia. To see the most recent views of roads at more than 100 places in Finland, click here. For people who have never seen snow, let alone driven on it, be warned that snow and ice are slippery. Road accidents can occur all too easily in such conditions.
How do people dress for snowy weather? Click here (and then scroll down the page) to see a group of MetLink students out in the snow at Fernley, Nevada. For another snowy view, this time of Oslo in Norway, click here. Fresh snow looks clean and, to many people, pretty. Melting snow can, however, be quite unpleasant. Slush can be just as slippery as snow. Rutted frozen slush after a freezing night can be very unpleasant to walk or drive on. For a view of Oslo after a frosty night, click here. Notice the pile of snow on the left-hand side of the picture. This was formed by people clearing the snow from places where it was a particular nuisance.
Snow falls in the British Isles, too, but not very often. Click here for a snowy view of Edinburgh during MetLink 2002. To find out how often snow falls in the UK, click here and then choose ‘Snow’. As might be expected, the number of days on which snow falls is greatest in the mountainous parts of the British Isles. Generally, people in the UK are not prepared for heavy snow. In defence of the British people, however, the snow that falls in the British Isles is not normally the powdery dry stuff that falls in very cold places. It’s more often than not a rather wet, heavy form of snow. When snow forms into deep drifts, transport is badly affected. A popular pastime with young people in the British Isles and elsewhere is throwing snowballs at each other, these being lumps about the size of a tennis ball formed by pressing handfuls of snow. People also amuse themselves by building snowmen (figures resembling humans) made of compressed snow.
The ancient Romans thought the British Isles a foggy, cloudy, windy, damp place, and that is the perception many people around the world have of these islands. Webcam views during MetLink 2002 have tended to confirm this impression, as the views of western Scotland (Kyle of Lochalsh) on 22 January, Leicester on 24 January and Plymouth on 25 January show. The weather can, however, be sunny, as these views of Manchester and Norwich on 22 January show. On a mild day in late January, the temperature can rise to 10 or 12°C or more in the British Isles. On a cold night, temperatures may fall below —10°C, but that does not happen very often. A mixture of architectural styles can be seen on this view of Newcastle upon Tyne, including old and modern office blocks, factories and high-rise tower blocks that contain apartments. Central heating is the norm in British houses, schools and offices from September to May. To investigate the British climate, visit the UK Met Office’s UK Climate web pages.
Winter weather is variable in France and Germany, too, as MetLink observations have shown. There can be mild days when it is warm enough to relax out of doors, as this image shows. The following day, the weather can be quite a contrast! In Romania, too, winter brings dismal days and sunny days, with heating of houses, schools, offices, etc necessary for several months of the year. As we have seen from MetLink 2002, winter weather can also be cold in Japan, another place where buildings need to be heated for several months of the year.
Two contrasting views of North Carolina can be seen in the airport webcams we showed on 22 and 23 January, one taken in damp conditions, the other in sunny. Click here for a view of the airport today. As we have seen in MetLink 2002, there can be days in January when the temperature in North Carolina fails to rise much above 0°C and there can be others when it tops 20°C.
Holiday brochures do not show pictures like this one of Banff in Canada. Instead, they show pictures taken from the same view point in clear weather, when the view of the Canadian Rockies is stunning. Holiday brochures are designed to make people want to visit the particular localities which they feature. Wherever you go in middle latitudes, the weather can be changeable. You may be lucky and experience brilliant weather. You may be unlucky and have such a wet and cloudy holiday that you rarely see the scenery at its best. Have a look at some holiday brochures. Do they build up your weather expectations too much? Do they contain any information at all about the variability of the weather where you plan to go? How honest are holiday brochures about the weather at your destination? Do they always show places in fine weather?
The webcam on Mount Wilson in California shows some stunning views, like this one over Los Angeles, which is a little hazy because of automobile and other fumes trapped under a temperature feature called an ‘inversion’. The problem is worst in summer, when the combination of sunshine and high temperatures causes photochemical smog, which can be very irritating to eyes and lungs. This type of smog occurs wherever traffic densities are high and the weather is hot and sunny. It even occurs sometimes in south-east England, which would probably have amazed the ancient Romans, who would not have thought the weather of the British Isles at all conducive to photochemical smog formation! But back to Mount Wilson … the weather there is often beautiful and the views can be spectacular.
Weather webcam pictures of MetLink locations in low latitudes are hard to find. If you know of any in your part of the world, do please tell us. One we do know of is the one at the port on Ascension, where the weather is often sunny and the sea blue.
To find weather webcams around the world, click here. To find UK weather webcams, click here. And on the MetLink website, there are many more webcams than have been featured here. You can find them in the MetLink daily weather reports.
To return to Today’s Review of MetLink Observations, click here.
To return to Today’s Analysis, click here.
NOTES
SATELLITE IMAGES FROM DUNDEE
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.