Also known as a ‘dust devil’, a willy-willy is a vortex of dust formed by wind. (Source: http://www.metoffice.gov.uk/learning/learn-about-the-weather/weather-phenomena/willy-willy)
At least 3 days of heavy rainAt least 4 days of heavy rain and winds of 35mph+A seasonal wind shift
A monsoon is a seasonal wind shift that mostly occurs in tropical parts of the world, not just a period of heavy rainfall as it often seems to be dubbed in the media. Monsoons commonly occur in India, East Africa and South-East Asia. These wind shifts, which persist for months, can bring moist air from the sea to land which leads to “monsoon rains”. However some monsoons are dry and can cause droughts. (Source: http://education.nationalgeographic.org/encyclopedia/monsoon/)
Snow with winds or gusts at 35mph+Snow that frequently reduces visibility to <1/4 of a mileContinuous snow for 3+ hoursAll of the above
All 3 of the criteria must be met for such a weather formation to count as a blizzard. (Source: http://glossary.ametsoc.org/wiki/Blizzard)
About once a weekAbout once a monthAbout once a yearAbout once a decade
We frequently see headlines like “UK hotter than [somewhere that sounds hot]”. Greece, Spain and other Mediterranean locations are popular targets, and sometimes Australia is mentioned (where it is usually winter AND night time). There are so many places to choose from that you could write a headline like this most days. For more details on this, get in touch with enquiries[at]senseaboutscience.org.
October 1987 (the “Great Storm”)August 2014 (Bertha)October 2015 (Joaquin)NeverVia Wikicommons
The UK is often hit by strong storms, some with hurricane-force winds (>74mph). However the UK has never been hit by a hurricane and probably never will be. Hurricanes are tropical storms that only form in the tropics and are much stronger than anything we experience. They get their energy from warm seas, and can produce half-a-metre of rain in a day (roughly equivalent to London’s rainfall in a year) and wind gusts over 200 mph. Sometimes these storms head towards the UK, but when moving across the cooler North Atlantic, they lose much of their energy (fortunately for us). Sometimes they will still be known as ‘ex-hurricane XXXX’, but this is for ease of reference rather than because they are any more significant than other storms we experience. (More information on hurricanes: http://blog.metoffice.gov.uk/2013/10/26/the-severe-storm-this-weekend-and-why-its-not-a-hurricane/)
HorseVia Coen Dijkman (CC BY-SA 2.0)Pronghorn antelopeVia U.S. Department of Agriculture (CC BY 2.0)CheetahVia Michael Moss (CC BY-ND 2.0)GreyhoundVia saris0000 )CC BY-ND 2.0)
Hurricane-force winds come in at a whopping 74mph, about as fast as a cheetah. But remember, just because the winds are hurricane-force it doesn’t mean it’s a hurricane! (More info on hurricanes: http://blog.metoffice.gov.uk/2013/10/26/the-severe-storm-this-weekend-and-why-its-not-a-hurricane/; http://www.metoffice.gov.uk/weather/tropicalcyclone/hurricane)
1946-1947Via Julia Rubinic (CC BY 2.0)1962-1963Via Gene Bowker (CC BY-ND 2.0)1978-1979Via Wystan (CC BY 2.0)2009-2010Via Junya Ogura (CC BY 2.0)
Beginning in December and lasting until March, the UK experienced its coldest winter for over 200 years in 1962-1963, and it is still the coldest winter recorded since 1740. Temperatures dropped below -20 degrees, lakes and rivers froze over, animals starved, and villages were cut off. Visit the MET office website to find out more (http://www.metoffice.gov.uk/learning/learn-about-the-weather/weather-phenomena/case-studies/severe-winters).
Although relatively rare, thundersnow is the term given when a thunderstorm produces snow. Thunderstorms require a lot of energy (usually hot air) and so they rarely form in winter. (Sources: http://www.metoffice.gov.uk/learning/learn-about-the-weather/thunder-and-lightning/thundersnow; http://news.nationalgeographic.com/news/2009/03/090303-thunder-snow-storm.html)
…5 degrees for 5 consecutive days”…5 degrees for 7 consecutive days”…10 degrees for 1 day”
We often hear a a spell of hot weather called a ‘heatwave’. But if it doesn’t match the criteria above then strictly speaking it can’t be classed as a heatwave. (Source: http://www.metoffice.gov.uk/learning/learn-about-the-weather/weather-phenomena/heatwave)
There is an 80% likelihood that it will rainThere will be rain in 80% of that areaThere will be rain for 80% of the time
Meteorologists use models to make predictions about the weather and these are improving all the time. However, weather is very unpredictable at small scales (e.g. it might be raining on one side of a town but not the other), so even the most advanced models can’t be 100% certain. Visit the Met office website to find out more about their modelling systems for forecasts (http://www.metoffice.gov.uk/research/modelling-systems), and read our ‘Making Sense of Uncertainty’ guide to find out more about the role of uncertainty in science (http://bit.ly/1ZlUsf4).