March 19 — day of the year, seasonal boundary, and cultural observances

Seasons and astronomy

Because the astronomical vernal equinox commonly occurs on March 20 or 21, March 19 is frequently the last day of winter in the Northern Hemisphere and correspondingly the final day of summer in the Southern Hemisphere. Meteorological and astronomical definitions of seasons differ: meteorological seasons follow fixed calendar months while astronomical seasons are determined by equinoxes and solstices. This causes the exact seasonal boundary near March 19–21 to vary across years and time zones. For background on leap-year adjustments see leap years and on the governing calendar system see the Gregorian calendar. The terms winter, Northern Hemisphere and Southern Hemisphere are often referenced when describing how this date relates to seasonal change.

Observances and traditions

Several religious and cultural observances fall on or are commonly celebrated on March 19. The most widely recognized is the Catholic feast of Saint Joseph, traditionally commemorated on this date. In many Catholic communities the day is observed with liturgies, processions and local foods. In parts of Europe and Latin America Saint Joseph's Day also coincides with popular customs and, in some countries, with Father’s Day festivities.

Common practices and variations

• Religious observance: Liturgical services and community festivals marking Saint Joseph's role in Christian tradition.
• Culinary customs: Regional pastries and special meals associated with the feast in Italian and Iberian cultures.
• Calendar mechanics: In a leap year the ordinal number of the date increases by one, shifting later dates by a day for the remainder of that year.

Across history many unrelated events have occurred on March 19; the date’s significance varies by culture, religion and local tradition. For calendar-related topics and seasonal definitions users may follow the placeholder links above to explore leap years, the Gregorian system and hemispheric season names.