TRENDS for the week of 7 to 13 May 2021 --
-- Temperatures will be 1 to 2 deg below normal values.
-- Rainfall will be near normal to 25 per cent above normal in parts of the west and south.
-- Sunshine will be 50 to 75 per cent of normal values. Winds will be generally moderate.
FORECASTS
TONIGHT will become cloudy with outbreaks of rain spreading into the
south and west, 10 to 20 mm likely. Winds increasing to southeast 40 to
60 km/hr, stronger gusts at times in west Munster. Lows 6 to 9 C.
SATURDAY will bring some further outbreaks of rain, then a dry interval
is likely to spread into parts of the southern and central counties with
a few brighter intervals, warmer than in recent days, highs 14 to 17 C.
Some further rain is likely near Atlantic coasts and in north Connacht
and parts of Ulster with highs 12 to 15 C there. The moderate southerly
breezes will tend to die off gradually by evening.
SUNDAY will have variable amounts of cloud and frequent showers or
intervals of rain, another 10 to 15 mm rain is expected. Still rather
mild with temperatures steady in the range of 11 to 14 C. Some intervals
of moderate southeast winds near south coast and exposed higher
terrain.
MONDAY will be partly cloudy to overcast with showers, a few isolated
thunderstorms and risk of hail, light winds as the low, while now almost
over the centre of the country, weakens to a very slack gradient.
Temperatures steady in the range of 10 to 13 C. Further rainfalls of
5-10 mm likely.
TUESDAY will turn a bit colder as winds start to turn more to the
northeast, occasional showers or intervals of light rain, 3-7 mm on
average, and temperatures steady 8 to 11 C.
From that point on, the unsettled weather will very gradually improve
but only partial clearing is likely, which will prevent frosts from
being very widespread as had been anticipated when higher pressure was
expected to push in, now it looks like a rather slack gradient will
continue but the full effects of the colder air mass will only be seen
further north to northwest, however, it should be cautioned that we
can't entirely rule out a return to the more significant cold pattern as
this guidance is only moderately reliable with things grinding to a
halt in terms of steering currents and large-scale ridges and troughs.
The most likely longer term outcome is probably somewhat warmer than
average weather for a while by the third week of May.