TRENDS for the week of 28 Jan to 3 Feb 2021
-- Temperatures will average near normal.
-- Rainfall will average 75 to 100 per cent of normal.
-- Sunshine will average 50 per cent of normal, possibly less in the south, a little better in Ulster.
FORECASTS
TODAY will start out mostly cloudy with any remnant drizzle in the north
gradually ending, otherwise, dry to mid-day or early afternoon for
many, then intervals of light rain, and gradually increasing southwest
winds in the south coast counties (less windy further north). Highs 8-11
C except 4-7 C in the north.
TONIGHT will see a few further outbreaks of light rain and the moderate
southwest winds 50-80 km/hr will gradually ease near the south coast,
lows 4-7 C.
FRIDAY will have a few dry intervals, as winds turn more southeast to
easterly, then rain will arrive again in the south, west and central
counties, spreading to Leinster by late afternoon or early evening. This
rain could start to change over to sleet or wet snow on high ground
because somewhat colder air will be gradually feeding into the rainfall
but closer to the south coast it will remain 8 or 9 C and 15-30 mm rain
can be expected there. Temperatures further north may slowly fall off to
around 5 C at lower elevations, 2-4 C on higher ground.
SATURDAY some rain will continue mixed with sleet or wet snow on higher
ground in some parts of the south; it will likely be dry but mostly
cloudy with a few brighter intervals further north. Temperatures will
vary from 7 C in the south to 2-5 C in the north.
SUNDAY another weak system will try to push the colder air back to the
north but it may take until Sunday night before there is much change in
the frontal zones, so that a cold rain in the south may trend more
towards sleet or wet snow in central counties and if it reaches far
enough north, measurable snowfalls are possible in south Ulster.
Temperatures will remain around 4 to 7 C for most, 2 to 5 C north, and
10-20 mm rain or liquid equivalent can be expected.
MONDAY the milder air may have one last attempt to push north, and may
succeed briefly but then the system will weaken and colder air will seep
back into the north later in the day. Some rain at times with fog
likely, highs near 7 to 9 C in the south, 3 to 6 C north.
By TUESDAY a somewhat cooler easterly flow will develop, and this could
have some mixed wintry showers although it looks fairly settled, with
highs near 5 C.
The pattern for the rest of next week looks rather cloudy with east
winds and perhaps a few more minor skirmishes in the south between
somewhat milder air and the gradually dominating colder air. This could
lead to a few intervals of sleety rain or wet snow. However, the big
weather story may be what happens towards the end of next week, as most
guidance seems to be tracking similar outcomes with much colder air
settling into northern Europe and then gradually extending its influence
over most of Britain, with Ireland perhaps in line for a visit too by
about Sunday 7th February, and if so this could be quite a cold interval
with snowfall potential especially near the east coast. By no means is
this certain to happen (based on usual model reliability, about a 60-70
per cent chance however).
-- Peter O'Donnell is Irish Weather Online's Senor Forecaster.