The Spanish Plume (Penacho Ibérico in Spanish and Spaanse Pluim in Dutch) is a weather pattern in which a plume of warm air moves from the Iberian plateau or the Sahara to northwestern Europe, causing thunderstorms. This meteorological pattern can lead to extreme high temperatures and intense rainfall during the summer months, with potential for flash flooding, damaging hail, and tornado formation. Some of these intense thunderstorms are formed from thermal lows, which are also known as heat lows. Thermal lows can be semipermanent features around some parts of Europe, particularly in the summer season. These thermal lows can be developed or created around Spain, Portugal, France, etc., during the summer season because of the intense heat. Thermal low pressure can be located around the world, particularly in the summer or in tropical regions.
Satellite view 28 June 2012 showing low to west of Europe
1788, 13 July, a hailstorm sweeps across France and the Dutch Republic with hailstones 'as big as quart bottles' that take 'three days to melt'; immense damage is done.[1]
1897, 24 July saw thunderstorms disrupt the celebrations of Queen Victoria's Diamond Jubilee.[3]
1955, 18 July a Spanish Plume brought a record amount of rain on one day to Martinstown Dorset, with slow-moving thunderstorms bringing 279mm of rainfall.[4] A record which stood for over 50 years until the 2009 Cumbria floods.[5]
1958, 5 September Horsham storm, heaviest hailstone recorded in the UK (190g).[6]
1961, 12 August synoptic set-up of a Spanish Plume, however dry ground conditions in France led to little evaporation which led to lack of moisture in the air to fuel cloud and storm formation.[6]
2004, 3–5 August severe thunderstorms affected London and South East England and caused a lightning strike on the track on the South West Main Line at Earlsfield which blew the signals out causing severe delays and later caused flooding near Wimbledon on the District Line on 4 August.[20]
2011, 18 August a severe storm battered the Pukkelpop festival in Belgium. This situation shows some similarities with the Spanish Plume.[21]
2012, 10 May high temperatures reported in south of England with a tornado in Belgium reaching 100mph gusts in Ghent.[22][23]
2013, 26–27 July A Mesoscale convective system developed in France and moved across the Netherlands and northern Germany, a gust of 102mph was recorded at Pauillac, France from the storm. Smaller scale thunderstorms developed in the UK.[27]
2014, 17–21 July severe storms left at least two fatalities in France, with power cut to thousands of homes and localised flooding occurring in France and the United Kingdom.[30][31]
2015, 30 June–4 July A plume brought high temperatures from Spain across France and the UK. In France some July temperature records were set, and in the UK some all time maxima were set in some locations.[32][33] Severe thunderstorms also moved northwards across the UK on 1 July and again overnight 3–4 July.[34]
2016, 6–7 June A Spanish plume event brought extensive thunderstorm activity across the UK and Ireland,[35] resulting in the hospitalisation of a man and his children after being struck by lightning in Lisburn, Northern Ireland.[36]
Mexican Plume
A similar pattern, though on a larger scale, is the Mexican plume in the south west USA, where hot dry air from the Mexican highlands acts as a cap to convection until lifted over Texas, Arkansas and Oklahoma.[6][37][38]
Eastern Baltic
In Finland and the Baltic states meteorologists have observed a situation conducive to severe summer storm development which occurs when a warm moist air mass flows into the region from the south or south east under the influence of an upper-level trough. These conditions have some similarities to the Spanish plume.[39] The synoptic conditions see a low over southern Norway, bringing warm south and southwesterly flows of air up from the inner continental areas of Russia and Belarus.[40]
Webb, Jonathan D. C. (2011). "The great summer heatwaves of 1975 and 1976 in the UK, and some violent storms". International Journal of Meteorology. 36: 255–261.
McCallum, E.; Waters, A. J. (July 1993). "Severe thunderstorms over south-east England, 20/21 July 1992: Satellite and radar perspective of a mesoscale convective system". Weather. 48 (7): 198–208. Bibcode:1993Wthr...48..198M. doi:10.1002/j.1477-8696.1993.tb05886.x.
van Delden, A. (1998). "The synoptic setting of a thundery low and associated prefrontal squall line in western Europe". Meteorology and Atmospheric Physics. 65 (1–2): 113–131. Bibcode:1998MAP....65..113D. doi:10.1007/BF01030272. S2CID67786470.
Lewis, Matthew W.; Silkstone, Nicholas (April 2017). "Improvements in nowcasting capability: analysis of three structurally distinct severe thunderstorms across northern England on 1 July 2015". Weather. 72 (4): 91–98. Bibcode:2017Wthr...72...91L. doi:10.1002/wea.2837. S2CID126199006.
