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The weather forecasters promised a windy day for the British Isles, and so it proved. As the MetLink data base shows, the wind was quite strong at many British schools, with 56 kph reported at Edgbaston High, 44 kph at several schools and a gust of 64 mph (over 100 kph) at Farr High School in the north of Scotland. The strongest winds at land stations occurred in western Scotland and northern parts of Ireland and gales occurred over many sea areas around the British Isles. At 1200 UTC today, a deep depression with a central pressure of 952 mb was almost exactly where the forecasters said it would be. Its centre was at 60°N 24°W, just four degrees of longitude west of the forecast position. During the afternoon, the buoy at 55°29'N 13°00'W reported a sustained wind of 19.5 m/s (70 kph).
In the Orkney and Shetland Islands and over the most north-easterly part of Scotland, the winds blew from the south-east. Over the rest of the British Isles, winds blew from between south-west and west. As winds blow anticlockwise around depressions in the northern hemisphere, these winds were consistent with an area of low pressure being located north-west of Scotland.
Today's Meteosat and Dundee images show an almost textbook example of the fronts associated with a vigorous depression (warm, cold and occluded fronts). These fronts raced across England, Wales and Ireland this morning, clearing the south-eastern corner of England about 1200 UTC. More stormy weather is forecast for northern parts of the British Isles tomorrow, but the weather over much of England and Wales is expected to be fine. This respite from the recent unsettled weather may, however, be short-lived!
In the Reading area today, rain was falling steadily from nimbostratus cloud at 0700 UTC. By 0900, the rain had almost stopped and breaks in the nimbostratus were beginning to appear. By 1000, the clouds were mainly cumulus with ragged bases, with some altocumulus above. For most of the day, thereafter, there was dry weather, with cloud amounts varying from only 1/8 at some times to almost 8/8 at others. Sometimes, showers threatened, but, in fact, no showers materialised in Reading until 1745 UTC, when there was a brief heavy one and a short period of strong gusts. Throughout the day, the clouds moved very quickly, blown along by strong winds in the upper atmosphere. In the centre of Reading, the wind strength was Beaufort Force 5 or 6 throughout the day.
Pressure was high (1039 mb) to the south-west of Portugal, with a weak ridge of high pressure extending over Iberia. At the MetLink stations in Spain and Portugal today, contrasting weather was reported. Vidal had sunny weather, but Gabriel Pereira had grey, cool weather. The weather was overcast, too, and mild at the MetLink schools in Sweden and Finland, with rain at Bor School. In Cyprus this morning, it was again sunny and cool, with high pressure (1029 mb) over Turkey. By 1000 UTC, though, the temperature at Akrotiri had risen to 15°C. In Geneva at 1100 UTC, the sky was overcast and the weather wet.
At Edmonton, Canada, temperatures were above 0°C in the early afternoon, after falling to about -9°C overnight. Temperatures were well below -30°C to the west of Hudson Bay but close to feezing point during daylight hours in southern British Columbia, southern Alberta and southern Saskatchewan.
Once again, smoke was reported hour after hour at Bombay's Santa Cruz Airport, indeed every hour from 1300 UTC (1830 local time) on 7 February to 0800 UTC (1330 local time) today. For much of the time, the wind was calm, as on previous days.
Temperatures were again in the twenties and thirties Celsius at the MetLink schools in Oman, Ethiopia and Uganda, and at the school on Ascension. They were, too, at the schools in southern Africa, but conditions were rather cloudy there (as they were, in fact, again, over Ascension). Today's Meteosat images show that cumulus and cumulonimbus clouds were present over a wide area of southern Africa today, with the greatest activity again just south of the equator at about 20°E. A depression centred over Kwazulu-Natal again gave Hilton College humid, overcast conditions. At the MetLink school in Kampala, Uganda, there was drizzle this morning.
Schools in Africa: at what times of day does precipitation tend to fall, or can it fall at any time?
At Southmoor Primary School, south-east Australia, today, the temperature reached 31°C. Today's JMA/GMS satellite image of Australia shows a lot of cloud (mostly high cloud) over northern and central Australia and a band of cloud south of Tasmania, the latter associated with a cold front. There were some clouds over Victoria as well, though skies were clear at Melbourne for much of the day.
What do you use for finding out wind direction? Do you use a wind sock? Do you use a vane? Have you tried making a vane yourself? Do you observe smoke or flags to find wind direction? How much does the wind direction vary over a few minutes?
To those of you who made observations more than once today to provide information about the changes that occurred as the fronts travelled across the British Isles, many thanks.
The weather forecasters promised a windy day for the British Isles, and so it proved. As the MetLink data base shows, the wind was quite strong at many British schools, with 56 kph reported at Edgbaston High, 44 kph at several schools and a gust of 64 mph (>100 kph) at Farr High School in the north of Scotland. The weather has certainly been in lively mood today! The strongest winds at land stations occurred in western Scotland and northern parts of Ireland and gales occurred over many sea areas around the British Isles. At 1200 UTC today, a deep depression with a central pressure of 952 mb was almost exactly where the forecasters said it would be. Its centre was at 60°N 24°W, just four degrees of longitude west of the forecast position. During the afternoon, the buoy at 55°29'N 13°00'W reported a sustained wind of 19.5 m/s (70 kph).
Here, as at most stations in the British Isles, the wind blew from the west or west-south-west. In the Orkney and Shetland Islands and over the most north-easterly part of Scotland, however, the winds blew from the south-east. These places lay to the north of the occluded front which extended from southern Iceland to the central part of the North Sea. South of the front, winds blew from between south-west and west. Today's satellite images are collectors' items so far as 'classical' pictures of fronts are concerned. Both the Meteosat and Dundee images show an almost textbook example of warm, cold and occluded fronts associated with a vigorous depression. The warm and cold fronts raced across England, Wales and Ireland this morning, clearing the south-eastern corner of England about 1200 UTC.
In the Reading area, rain was falling steadily from nimbostratus cloud at 0700UTC. By 0900, the rain had almost stopped and breaks in the nimbostratus were beginning to appear. By 1000, the clouds were mainly cumulus with ragged bases, with some altocumulus above. For most of the day, thereafter, there was dry weather, with cloud amounts, mainly rather ragged cumulus, varying considerably -- sometimes only 1/8, at other times almost 8/8 and threatening showers. In fact, no showers materialised in Reading until 1745 UTC, when there was a brief heavy shower and a period of strong gusts. Throughout the day, the clouds moved very quickly, and at 1200 UTC the nearest upper-air ascent to Reading, at Herstmonceux, 80 km SSE of London, showed that winds were blowing there at 107 kph (from the west) at an altitude of 1,500 m. They were blowing at 120 kph at 4,000 m and as much as 232 kph at 10,000 m. In the centre of Reading during the day, the wind strength was Beaufort Force 5 or 6.
In western and northern parts of the British Isles, there was a lot of shower activity. There were showers, too, over the waters to the west of Scotland, as satellite images show very clearly. Over these sea areas, the images show the speckling that is characteristic of cumulus and cumulonimbus activity. The clouds tend to be clustered. Given the tendency for winds to be particularly gusty near cumulonimbus systems, the showers were probably rather blustery.
More stormy weather is forecast for northern parts of the British Isles tomorrow, as depressions move rapidly north-eastwards from the Grand Banks of Newfoundland to the waters south of Iceland. The cold front that crossed the British Isles during the morning trailed south-westwards to the Azores and crossed northern Spain. Pressure was high (1039 mb) to the south-west of Portugal, with a weak ridge of high pressure extending over Iberia. Tomorrow, a ridge of high pressure is expected to extend as far north as southern parts of the British Isles, giving these parts a respite from the recent unsettled weather. The respite may, however, be short-lived.
At the MetLink stations in Spain and Portugal today, contrasting weather was reported. Vidal had sunny weather, but Gabriel Pereira had grey, cool weather. The weather was overcast, too, and mild at the MetLink schools in Sweden and Finland, with rain at Bor School. In Cyprus this morning, it was again sunny and cool, with high pressure (1029 mb) over Turkey. By 1000 UTC, though, the temperature at Akrotiri had risen to 15°C. In Geneva at 1100 UTC, the sky was overcast and the weather wet, the fronts of the depression centred south of Iceland being responsible.
At Edmonton, Canada, temperatures were above 0°C in the early afternoon, after falling to about -9°C overnight. As weather charts from Canada show, Alberta lay in a col, between depressions over Hudson Bay and the eastern Pacific and highs over the far north-west of Canada and the south-west of the USA. Temperatures were well below -30°C to the west of Hudson Bay but close to feezing point during daylight hours in southern British Columbia, southern Alberta and southern Saskatchewan.
Once again, smoke was reported hour after hour at Bombay's Santa Cruz Airport, indeed every hour from 1300 UTC (1830 local time) on 7 February to 0800 UTC (1330 local time) today. For much of the time, the wind was calm, as on previous days.
Temperatures were again in the twenties and thirties Celsius at the MetLink schools in Oman, Ethiopia and Uganda, and at the school on Ascension. They were, too, at the schools in southern Africa, but conditions were rather cloudy there (as they were, in fact, again, over Ascension). Today's DTOT and ETOT Meteosat images show that the Intertropical Convergence Zone (ITCZ) was active over a wide area of southern Africa today, with the greatest activity again just south of the equator at about 20°E. A depression centred over Kwazulu-Natal again gave Hilton College humid, overcast conditions. Kampala had drizzle in the morning. Schools in Africa: at what times of day does precipitation tend to fall, or can it fall at any time?
Finally, we visit south-east Australia, where the temperature at Melbourne (Southmoor Primary School) reached 31°C. Today's JMA/GMS satellite image of Australia shows a lot of cloud (mostly high cloud) over northern and central Australia and a cold front south of Tasmania. There were some clouds over Victoria as well, though skies were clear at Melbourne for much of the day.
PITSFORD HALL WEATHER STATION NORTHAMPTONSHIRE
WEATHER REPORT issued at 0900 hours
The Forecast for Northamptonshire
Tuesday, February 8, 2000
A system of weather fronts is currently tracking across the county
bringing some light rain to many areas. There are also some strong
winds and these will remain with us throughout the day, possibly
gusting up to gale force. The cloud and rain should clear away to the
east later to give a bright and dry end to the day. The top temperature
11C, but feeling very cold once the rain passes. The night will remain
windy with some scattered showers for many areas. Minima around 3C
Outlook: Mainly dry tomorrow with some sunshine, but strengthening
winds will herald the arrival of another front with rain for Thursday.
Metlink passage of a front across the UK The weather forecasters are predicting stormy weather for some parts of the British Isles tomorrow (Tuesday 8 February). It would be interesting to follow the progress of the day's weather. I wonder if each school in the UK and Ireland taking part in the MetLink project, and also the school at Stavanger, could send me an email message tomorrow afternoon describing the sequence of weather, cloud amounts, cloud types (if possible), wind speeds and wind directions you experienced during the day, with timings. Maybe the reports could be the words of your students, or a mixture of yours and the students'. If you can't undertake this mini-survey, I shall understand, but I think it would be interesting to follow the day's weather and put the reports on the MetLink website with charts and satellite images. Best wishes Malcolm Walker