TRENDS for the week of 2 to 8 April, 2021
-- Temperatures will average 3 to 5 deg below normal values, with the first two days closer to average.
-- Rainfalls will be about 25 per cent of normal values, or less in some
areas, as wintry showers on Monday and Tuesday are not likely to
produce heavy precipitation. Some rain late Sunday is the main producer
of any totals at all.
-- Sunshine will vary from 25 per cent below normal in some east and
north coast counties to 25 per cent above normal in the south and west.
These differences will build up in the first half of the interval. Most
places will be rather cloudy from Sunday to next Wednesday.
-- Winds will be light to moderate until Sunday afternoon or evening,
then rather strong for about a day and a half before backing off to
moderate again.
FORECASTS
TODAY will see a continued presence of some cloud near the east coast
and cool temperatures with highs 8 to 13 C, some low cloud or sea fog
and drizzle is possible at times, but not too far inland some brighter
spells will likely be encountered. Further west and in particular near
the west coast, the easterly flow will allow for warmth to spread to the
coast and bring temperatures up to 14 C and locally 16 C, although some
drifting low cloud and sea fog could be near all coastlines at times.
TONIGHT will see fairly extensive clearing and light frost is possible inland, lows -2 to +3 C.
By SATURDAY the easterly flow will be replaced by variable then light
westerly breezes and this could push in marine cloud layers over parts
of Ulster and Connacht, while sunshine prevails further east on this
occasion. Lows of 1 to 4 C and highs about 12 to 15 C are expected.
EASTER SUNDAY will start off in this same moderate air mass, but it will
be rather suddenly replaced by much colder air arriving mid-afternoon
in the north to early evening in the south, on strong northwest to north
winds. Morning lows 1 to 4 C, afternoon highs 8 to 11 C north, 11 to 14
C south. Temperatures will fall quickly in the late afternoon and
evening, rain turning to sleet or snow in some places, although
accumulations expected to be patchy 1-2 cm.
MONDAY will be unseasonably cold with strong north winds 50 to 80 km/hr,
some higher gusts to 100 km/hr in exposed coastal locations adding a
chill to near record low temperatures starting out around -1 or -2 C and
working back to only highs of 3 to 6 C. Passing wintry showers could
lay down some temporary coatings of snow, or graupel (a form of hail)
and snow pellets are likely too, some thunder may develop in heavier
showers. There will be a few brighter intervals especially across the
south. Wind chills may be as low as -4 C in some areas.
TUESDAY will be just about as cold although not quite as windy, and the
inland penetration of wintry showers may be somewhat reduced with
northern and western high ground seeing more of them, lows -2 to -4 C
and highs 3 to 7 deg C. Winds northwest to north 40 to 70 km/hr.
WEDNESDAY will bring a slight moderation as a weak warm sector develops
between this first outbreak and a second one following on, so as winds
become briefly westerly at 30-50 km/hr, under cloudy skies with some
rain at times, temperatures will recover a bit to 8 or 9 C after morning
lows near -1 C.
By THURSDAY into FRIDAY and the following weekend a second cold spell
may be somewhat less windy than the first one but it may also contain
more organized areas of mixed wintry precipitation as troughs rotate
around a stalled low in north-central Europe. There will probably be a
slight moderation each day after Friday, but highs on Thursday and
Friday could be only about 5 to 7 C, with slight frosts both mornings.
Eventually the pattern becomes somewhat less chilly but more unsettled,
so only slight improvements going into the middle of April.
Peterfor IWO