"De narices" = of noses*

1) damned / bloody.
2) serious / important
3) strong
"Hace un frío/calor de narices" (It is damned cold / hot // It's bloody cold / hot).
"Tenemos un problema de narices (We have a(n) serious / important problem)
"Tiene una personalidad de narices" (She/he has a strong personality)

NOTA: The expression "Estar hasta las narices" also carries a negative meaning, as it is translated as "to be fed up with " or "to be sick and tired of something".
"Estoy hasta las narices de este horario" --> I'm fed up with this timetable / I'm sick and tired of this timetable".