Met Eireann have datasets going back to 1985 on their website here. Some basic data munging on the Met Eireann set for Dublin Airport and I followed the rstats code from the tutorial above to build the graphs below. Wexford would be more interesting for Sun and Kerry for Rain and Wind but those datasets would not download for me.
The first is a comparison of the temperature in 2014 compared to the same date in other years.
Next I looked at average wind speed
And finally the number of hours of sun
maxtp: - Maximum Air Temperature (C)
mintp: - Minimum Air Temperature (C)
rain: - Precipitation Amount (mm)
wdsp: - Mean Wind Speed (knot)
hm: - Highest ten minute mean wind speed (knot)
ddhm: - Mean Wind Direction over 10 minutes at time of highest 10 minute mean (degree)
hg: - Highest Gust (knot)
sun: - Sunshine duration (hours)
dos: - Dept of Snow (cm)
g_rad - Global Radiation (j/cm sq.)
i: - Indicator