[Alvin Diogenes]

How can winter start on October 25th in Iceland when the start of winter for the entire Northern Hemisphere starts on Dec 21st.

Iceland has a traditional calendar which defines the first day of summer and winter in its own way. See http://www.icenews.is/2009/10/25/welcome-to-the-icelandic-winter/:

"... Iceland recognises the first day of summer as the first Thursday after the 18th April and the first day of winter as the Saturday between the 21st and 27th October."

[DaveA37]

Looks like a heavy frost here in Wisconsin.