If anyone wants to have a bunch of binary sensor entities for common date evaluations, just add these to your templates YAML.
# Months
- name: Is January
state: >
{{ now().month == 1 }}
- name: Is February
state: >
{{ now().month == 2 }}
- name: Is March
state: >
{{ now().month == 3 }}
- name: Is April
state: >
{{ now().month == 4 }}
- name: Is May
state: >
{{ now().month == 5 }}
- name: Is June
state: >
{{ now().month == 6 }}
- name: Is July
state: >
{{ now().month == 7 }}
- name: Is August
state: >
{{ now().month == 8 }}
- name: Is September
state: >
{{ now().month == 9 }}
- name: Is October
state: >
{{ now().month == 10 }}
- name: Is November
state: >
{{ now().month == 11 }}
- name: Is December
state: >
{{ now().month == 12 }}
# Days of Week
- name: Is Monday
state: >
{{ now().isoweekday() == 1 }}
- name: Is Tuesday
state: >
{{ now().isoweekday() == 2 }}
- name: Is Wednesday
state: >
{{ now().isoweekday() == 3 }}
- name: Is Thursday
state: >
{{ now().isoweekday() == 4 }}
- name: Is Friday
state: >
{{ now().isoweekday() == 5 }}
- name: Is Saturday
state: >
{{ now().isoweekday() == 6 }}
- name: Is Sunday
state: >
{{ now().isoweekday() == 7 }}
# Special Days
- name: Is First Day of Month
state: >
{{ now().day == 1 }}
- name: Is 15th Day of Month
state: >
{{ now().day == 15 }}
- name: Is Last Day of Month # Credit: https://stackoverflow.com/a/13565185
state: >
{%- set next_month = now().replace(day=28) + timedelta(days=4) -%}
{%- set last_day = next_month - timedelta(days=next_month.day) -%}
{{ last_day == now().day }}
# Holidays
- name: Is New Years Day
state: >
{{ now().month == 1 and now().day == 1 }}
- name: Is Groundhogs Day
state: >
{{ now().month == 2 and now().day == 2 }}
- name: Is Valentines Day
state: >
{{ now().month == 2 and now().day == 14 }}
- name: Is April Fools Day
state: >
{{ now().month == 4 and now().day == 1 }}
- name: Is Earth Day
state: >
{{ now().month == 4 and now().day == 22 }}
- name: Is May Day
state: >
{{ now().month == 5 and now().day == 1 }}
- name: Is Cinco De Mayo
state: >
{{ now().month == 5 and now().day == 5 }}
- name: Is Flag Day
state: >
{{ now().month == 6 and now().day == 14 }}
- name: Is Juneteenth
state: >
{{ now().month == 6 and now().day == 19 }}
- name: Is Independence Day
state: >
{{ now().month == 7 and now().day == 4 }}
- name: Is Veterans Day
state: >
{{ now().month == 11 and now().day == 11 }}
- name: Is Christmas
state: >
{{ now().month == 12 and now().day == 25 }}
- name: Is New Years Eve
state: >
{{ now().month == 12 and now().day == 31 }}