Shipping Forecasts:
Shipping Forecast (Met Office)
Inshore Forecast (Met Office)
Irish Sea Area Forecast (MET Eireann)

Weather Maps and Satellite Images:
Windy
Wind Guru
WeatherOnline
Theyr Precision Weather Planner
Surface Pressure Forecast (Met Office)
Satellite Imagery (Met Office)
British Isles Wind Map (XC Weather)
Weather Online
Forecast.co.uk
UK & Ireland Wind Chart (Magic Seaweed)