Overnight temperatures will also be high for many. When the Thunderstorm Warning is in force, the lightning location information enables the public to identify areas affected by the thunderstorms.For easy identification of the lightning locations, Hong Kong is divided into four regions : (1) New Terrritories West; (2) New Territories East; (3) Hong Kong Island and Kowloon; and (4) Lantau. Thunderstorm warnings issued by the Hong Kong Observatory are intended to give short-term (within one to a few hours) notice of the likelihood of thunderstorms affecting any part of Hong Kong. Friday saw 36.4C recorded at Heathrow and Kew Gardens, the hottest August day since 10th August 2003 (38.5C, Faversham), while 34.5C was recorded on Saturday and 34C on Sunday. The hot weather has resulted in Public Health England issuing heat health alerts for parts of England into next week. Hikers and people engaging in outdoor activities should bring along their radios or mobile phones with âMyObservatoryâ installed for the latest weather information issued by the Observatory. The delineation of the regions is shown below : Members of the public can click directly on the map in the âLocation-specific Lightning Alert Webpageâ to select the location of interest and the alert range according to user needs. Stay #WeatherAware pic.twitter.com/sSjUKuFk6W. The âRegional Information on Heavy Rain and Thunderstormâ webpage of the Observatory also displays dynamical information about Thunderstorm Warning and lightning locations. (iStock). As a rule of thumb, if the sound of thunder reaches an observer three seconds after a lightning flash, the thunderstorm is about one kilometre away from the observer. The highest temperature on record for the UK was 38.7C recorded at Cambridge Botanic Garden on the 25th July last year, while the hottest August day on record is 38.5C recorded at Faversham on 10th August 2003). Raw video: North Texas pelted with large hail as a severe storm moved through the area. Although much less frequent, tornadoes or waterspouts reaching the coast have caused damage to buildings in Hong Kong.Hailstones are hard pellets of ice usually of only a few millimetres in diameter although larger stones occasionally occur. The network monitors lightning activities over the Pearl River Estuary round the clock. The hot weather will continue for much of the week with heatwave conditions persisting in parts of southern and central England. Support your business with world-leading science and technology. Stay away from windows, crouch to the floor and protect your head with your arms or thick padding. Apart from direct strokes, people can also get hurt by electric shock when using or in contact with conductors or electrical appliances which come under the influence of these strokes. The explosive expansion of the surrounding air produces the rolling sound of thunder. During the passage of tornadoes or waterspouts, the direct impact of very strong winds and the difference in pressure between the interior and outside of a building can shatter weak structures, and even blow away trees and vehicles. You've successfully subscribed to this newsletter! Such thunderstorms are often localized and short lived. ©2020 FOX News Network, LLC. They are intense columnar vortices in the shape of funnel clouds with very strong winds and very low pressure near the centre. However, Chief Meteorologist Steve Ramsdale says; “a second yellow thunderstorm warning is also in place for parts of North West England, North Wales and West Midlands where the worst of the storms are likely to occur. They bring about abrupt increases in wind speed and drastic changes in wind direction. Occasionally, cumulonimbus clouds merge to form severe thunderstorms called supercells.On a summer day that sets off with fine weather, insolation may trigger the growth of cumulonimbus clouds and the formation of thunderstorms. Everything you need to know about the forecast, and making the most of the weather. After lightning has been detected by the network, the locations where lightning occurs are recorded and shown graphically on the Observatory's webpage and âMyObservatoryâ. A cumulonimbus cloud typically covers an area of a few kilometres in diameter with a vertical extent of ten kilometres or more, like a tower hanging in the sky. WHAT IS A MICROBURST? All market data delayed 20 minutes. Travis Fedschun is a reporter for FoxNews.com. Thunderstorms commonly occur in spring and summer months in Hong Kong. LIGHTNING is expected to hit swathes of the UK this week, bringing an end to a pleasant weekend of sun. "Along the Gulf Coast and across the Southeastern and Western states, most thunderstorms occur during the afternoon," the agency states. Isolated flooding is also possible more widely across England today through until Thursday due to further heavy thunderstorms. The National Oceanic and Atmospheric Administration's National Severe Storms Laboratory defines a severe thunderstorm as a storm that contains one or more of the following: hail one inch or greater, winds gusting in excess of 57.5 mph, or a tornado. All market data delayed 20 minutes. Who we are, what we do and organisational news. WHAT TO KNOW ABOUT THIS TYPE OF DAMAGING WIND. They are formed in well-developed cumulonimbus clouds associated with thunderstorms, mainly in spring. The latest breakthroughs, research and news from the Met Office. According to the NSSL, thunderstorms are most likely in the spring and summer months, particularly during the afternoon and evening hours, but they can occur year-round and at all hours. Here exceptional rainfall totals could be seen of 60mm in an hour with a very small chance of 150mm of rainfall in 3 or 4 hours”. https://www.foxnews.com/us/severe-thunderstorm-danger-weather-warning-storms Wind shear associated with squall lines is also a potential hazard to aircraft during landing and take-off.Under certain favourable conditions, thunderstorms are accompanied by tornadoes (over land) and waterspouts (over sea). Once issued, the warning is broadcast over radio and television, and announced on the Observatory's website, the “MyObservatory” mobile app and the Dial-a-Weather system (1878200). The areas of formation of the clouds may also vary with time.Thunderstorms are characterized by flashes of lightning and claps of thunder. A severe thunderstorm warning is issued if a thunderstorm becomes severe, or will soon turn severe. In general, thunderstorms produce lightning and tornadoes in addition to heavy rain that can cause flash flooding. The difference between a severe thunderstorm warning and severe thunderstorm watch. Caroline Douglass, Flood Duty Manager at the Environment Agency, said: “Heavy thunderstorms across the Midlands and the north-west of England could lead to surface water and river flooding in some communities with possible disruption to travel and flooding of individual properties this afternoon and into early Tuesday morning. In Canada, a rainfall rate greater than 50 millimetres (2 in) in one hour, or 75 millimetres (3 in) in three hours, is also used to indicate severe thunderstorms. The weather may even be sunny not far away from the storms. Yellow thunderstorm warnings are in place across the country between now and Thursday.. Today thunderstorm warnings cover much of the UK away from northern Scotland warning of the risk of heavy showers, frequent lightning and gusty winds with 30 to 40mm of rain possible in an hour. Outbreaks of heavy rain can be dangerous to people engaged in outdoor activities. Severe thunderstorms across parts of the northwest Monday 1600 – Tuesday 0300 There have been reports of small boats capsizing in nearby waters on encountering waterspouts. “Our teams are ready to respond where needed and we urge people to check their flood risk, sign up for free flood warnings and keep up to date with the latest situation online, call Floodline on 0345 988 1188 or follow @EnvAgency on Twitter for the latest flood updates.”. Today thunderstorm warnings cover much of the UK away from northern Scotland warning of the risk of heavy showers, frequent lightning and gusty winds with 30 to 40mm of rain possible in an hour. This is when warm air exists underneath much colder…. When the electric field arising from the piling up of charges reaches a certain breakdown value, lightning discharges take place between clouds or between cloud and the earth's surface. Sometimes, the cumulonimbus clouds will drift with the wind and affect other areas. A digest of the information is also made available to radio and television stations, and given in the Observatory's Dial-a-Weather system. Location-specific Lightning Alert Webpage, Regional Information on Heavy Rain and Thunderstorm, Automatic Regional Weather Forecast in Hong Kong & Pearl River Delta Region.  ", Get all the stories you need-to-know from the most powerful name in news delivered first thing every morning to your inbox. Here temperatures will locally reach the mid to high 30’s C, for much of the week though temperatures will start to fall from their peak from Thursday onwards. The typical life span of a cumulonimbus cloud is a couple of hours.In the vicinity of active weather systems such as low-pressure troughs, cumulonimbus clouds may form one after another. The hot weather will continue across the UK, with heatwave conditions for many, creating ideal conditions for thunderstorms which will bring heavy rain and increasing risks from flash flooding, lightning and hail.. Yellow thunderstorm warnings are in place across the country between now and Thursday. On average, thunderstorms are reported at the Hong Kong Observatory about 5 days per month during April to September.Most thunderstorms form in cumulonimbus cloud. As greenhouse gas concentrations increase heatwaves of similar intensity are projected to become even more frequent, perhaps occurring as regularly as every other year. If you encounter a tornado, seek shelter in a sturdy building. When thunder roars, there's good reason to heed the advice of forecasters and go indoors. This material may not be published, broadcast, rewritten, or redistributed. Verification, impacts and post-processing, Climate information for international development, Science for Impacts, Resilience and Adaptation (SIRA), Atmospheric processes and parametrizations, Regional model evaluation and development, Environmental Hazard and Resilience Services, National Meteorological Library & Archive. AccuWeather's Severe Weather Map provides you with a bird's eye view of all of the areas around the globe experiencing any type of severe weather. Such thunderstorms are more widespread and persistent. Follow him on Twitter @travfed, WHAT IS A MICROBURST? Whatever the weather we are all being urged to remember the Government Coronavirus guidelines. People on small boats on the open sea should watch out for the approach of squalls or waterspouts. Stay away from river courses or low-lying areas. Violent gusts refer to wind gusts with instantaneous wind speed reaching 88 km/h or higher (may also be understood as wind force instantaneously reaching storm force or higher categories) and are likely to occur in Hong Kong every year at varying frequency. ⚠️ Yellow Weather Warning Issued ⚠️ ©2020 FOX News Network, LLC. In an unstable and moist atmosphere, water droplets and ice pellets in the cloud will become electrically charged in convective motion. Drivers using highways and flyovers should be on the alert to violent gusts or intense gusts. Instead you should crouch down to minimise the area in contact between you and the ground. With strong summer sunshine at this time of year, UV levels will be high in some areas and you can check the UV forecast for your area here. Boats are known to have capsized in thunderstorm related squalls in local and nearby waters. Heatwaves are extreme weather events, but research shows that climate change is making these events more likely. All rights reserved. In addition to lightning, severe thunderstorms bring the threat of hail one inch or greater, winds gusting over 57.5 mph, or a tornado. This material may not be published, broadcast, rewritten, The immediate threat of severe thunderstorms has passed, but the situation will continue to be monitored and further warnings will be issued if necessary. Squalls or violent gusts often occur with thunderstorms. A scientific study by the Met Office into the Summer 2018 heatwave in the UK showed that it was 30 times more likely to occur now than in 1750 because of the higher concentration of carbon dioxide (a greenhouse gas) in the atmosphere.