May Weather

The weather was warm and sunny, for the most part, but more unsettled than April and generally drier that usual - continuing the dry conditions that have been affecting the growing conditions since the middle of March.

Only 35mm of rain fell this month (Dublin Airport conditions 16km away), but we would normally expect to get in the region of 55mm. The mean temperature for the month was only slightly above normal at 10.8 degrees C. The mean soil temperature was about 1 degree higher at 13.8C and the total amount of solar radiation for the month (intensity of energy from the sun including overcast days) was about 15% higher than normal (53850 Joules/sqcm). All of these conditions affect the growth rate of the plants, and the limiting factor was the lack of water.

In the temperature charts above (extracted from the Met Éireann summary) the maximum temperature for Dublin area (blue line) ranged in the mid teens for most of the month, but the low temperature dropped significantly at the end of the month, creating frost conditions on the night of May 29! This was a very late frost, but fortunately the garden was unaffected, most likely due to the 'heat island' effect of the urban environment. Although the frost didn't cause any damage, these low temperatures could have set back the growth of many of the plants.

The top graphs shows that the Dublin area did not get a substantial rainfall for the whole month, with the most rain falling on the 26th and 27th. The bottom graph shows a couple of spells of strong sunshine!