Updated to post a heat advisory for northeastern New Jersey, as
temperatures now forecast in the mid 90s will yield heat indices
between 100 and 105 this afternoon into the evening. Conditions
may be close for the NYC area, but with drier air expected to
mix lower dew points to the surface at peak heating, not enough
confidence exists that these conditions will be widespread.
Regardless, expect uncomfortable conditions for today. Previous
discussion below remains valid.