April - May
The shoulder season will be in full swing across most of Spain by April, except in the Canary Islands, where the first high season of the year will be winding down. In contrast, May is a shoulder season month across the country. Weather will warm up rapidly in these two months, and fewer crowds will be seen at most attractions. Keep in mind that festivals in some areas such as Seville can send hotel and transport prices high.
Bilbao and Barcelona will see highs in the upper 60s and low 70s, with lows in the 50s. Madrid and Valencia will see slightly rainier conditions in April and May, with highs in the upper 60s and low 70s, and lows around 50. Seville`s highs start around 70 in early April, warming to the 80-degree mark by late May. Lows are in the low to mid 50s. Gran Canaria`s highs should hover around 65 and lows are steady around 55.
Holidays and Festivals:
March or April - Holy Week (Semana Santa), with observed holidays as follows: Maundy Thursday (Jueves Santo) (Public holiday in all regions of Spain except Catalonia and the Valencian Community), Good Friday (Viernes Santo) (Public holiday in all regions of Spain), and Easter Monday (Lunes de Pascua) (Public holiday in Catalonia, the Balearic Islands, Navarre, the Basque Country and the Valencian Community). While not an official holiday, expect widespread closures across Spain on Easter Sunday (Domingo de Pascua).
Two weeks after Easter - April Fair (Feria de Abril), Seville. A large festival staging area is built along the Guadalquivir River, and locals celebrate with parties, food, and traditional sevillana dances.
April - Rock `n` Roll Madrid Marathon (Maratón de Rock 'n' Roll Madrid) and Rock `n` Roll Madrid Half Marathon (Medio Maratón de Rock 'n' Roll Madrid)
April 23 - St. George`s Day (San Jorge). In Aragon, the holiday (San Jorge o Diya d’Aragón in Aragonese) honors their patron saint, St. George. In Barcelona, the biggest draw on St. George`s Day are the large outdoor flower markets. Similar celebrations can be found across Catalonia. (Public holiday in Aragon)
April 23 - Castile and León Day (Día de Castilla y León), commemorating the Castilian victory at the Battle of Villalar, fought on this day in the year 1521. (Public holiday in Castile and León)
May - Bullfighting and zarzuela season (La temporada taurina y zaruzela), Madrid. Zarzuela is a performing arts genre unique to Spain that combines operetta, spoken word, acting and dance.
Early May - Festival of the Crosses (Festival de las Cruces). This holiday is celebrated with the most fervor in Andalusia, particularly in Córdoba, where there are processions and parties.
Early May - Córdoba Courtyards Festival (Los Patios de Córdoba), a world-renowned courtyard-decorating competition in which dozens of courtyard owners across Córdoba participate.
Early May - Feria del Caballo, Jerez de la Frontera, an event which includes historic re-enactments featuring horses, and other acts of horse pageantry.
May 1 - Labour Day (Día del Trabajador). It is celebrated with marches across Spain. Trade unions give `state of the union`-type speeches on the state of workers` rights in Spain today. Workers have a day off to spend with friends and family. (Public holiday in all regions of Spain)
May 2 - Regional Day (Community of Madrid) (Fiesta de la Comunidad de Madrid or Dos de Mayo), commemorating the 1808 Dos de Mayo Uprising against French Imperial forces. (Public holiday in the Community of Madrid)
Mid-May - Ibiza Medieval Fair (Feria medieval de Ibiza), featuring handicraft markets, `witches` and `wizards`, and acrobatic wall-dancing.
Mid-May - WOMAD (World of Music, Arts and Dance) Festival, Cáceres, Extremadura. A world music festival co-founded by the rock musician Peter Gabriel in 1980, it is free of charge to attend.
Mid-May - Titirimundi International Puppet Theatre Festival (Titirimundi, el festival de las artes de la marioneta), Segovia. One of the largest such festivals in the world, puppet performances are held at both indoor and outdoor venues, in addition to performances from street performers.
Mid-May - Fiestas de San Isidro, Madrid, honoring San Isidro, the patron saint of Madrid. Traditional dancing marks the holiday, in particular the celebration at San Isidro Park.
Mid-May - Spanish Grand Prix (Gran Premio de España), the largest Formula One car race in Spain, held at Montmeló near Barcelona.
May 17 - Galician Literature Day (Día das Letras Galegas in Galician). Celebrated each year since 1963, the centenary of the publication of Cantares gallegos, the first mass-published book in the Galician language, written by Rosalía de Castro. (Public holiday in Galicia)
May 30 - Canarians National Day (Día de Canarias), commemorating the first sitting of the Canarian Parliament on this day in 1983. (Public holiday in the Canary Islands)
May 31 - Regional Day (Castile-La Mancha), (Día de la Región Castilla-La Mancha), commemorating the dedications of the first regional courthouses that rule over the area. (Public holiday in Castile-La Mancha)
May or June - Pentecost (Pentecostés) and Whit Monday (Lunes de Pentecostés), expect closures in Barcelona.