Ireland · 1991–2020

Best time to visit
Portarlington.

July leads for comfortable weather in Portarlington: typically 19.4°C by day, 11.6°C at night, with 71 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortJuly

Typical high19.4°C

Typical low11.6°C

Rain in July71 mm

Comfort

July

July · August · June

64climate match

Beach

July

July · August · June

28climate match

Outdoors

August

August · June · July

77climate match

The weakest month is January, scoring 7 against July’s 64 — days reach only 8.4°C, 16° below the 24°C the score treats as ideal.

Month by month

The whole year,
without the guesswork.

The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.

Jan

78.4° / 2.3°

Feb

169° / 2.3°

Mar

2110.7° / 3.5°

Apr

3112.8° / 4.6°

May

4515.7° / 6.9°

Jun

5718.1° / 9.6°

Jul

6419.4° / 11.6°

Aug

6419.5° / 11.5°

Sep

5417.4° / 9.4°

Oct

3113.7° / 6.7°

Nov

1910.7° / 4.4°

Dec

98.6° / 2.5°

Monthly climate evidence for Portarlington — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	8.4°C	2.3°C	90 mm	15.7	8 h 03	7	Good coverage
February	9°C	2.3°C	59 mm	12.5	9 h 44	16	Good coverage
March	10.7°C	3.5°C	67 mm	13.6	11 h 40	21	Good coverage
April	12.8°C	4.6°C	68 mm	12.6	13 h 53	31	Good coverage
May	15.7°C	6.9°C	62 mm	13.2	15 h 48	45	Good coverage
June	18.1°C	9.6°C	72 mm	12	16 h 56	57	Good coverage
July	19.4°C	11.6°C	71 mm	13.9	16 h 29	64	Good coverage
August	19.5°C	11.5°C	81 mm	12.4	14 h 46	64	Good coverage
September	17.4°C	9.4°C	71 mm	13	12 h 36	54	Good coverage
October	13.7°C	6.7°C	100 mm	14.8	10 h 28	31	Good coverage
November	10.7°C	4.4°C	86 mm	15.2	8 h 33	19	Good coverage
December	8.6°C	2.5°C	88 mm	14.6	7 h 34	9	Good coverage

Records at BIRR, 1954–2009
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	14.5°C4 Jan 1957	-14.6°C12 Jan 1982	39 mm7 Jan 2005	151 mm1995 · driest 9 mm in 1963	55
February	15.5°C13 Feb 1998	-10.5°C17 Feb 1969	28 mm5 Feb 1990	169 mm1990 · driest 2 mm in 1986	55
March	19.7°C28 Mar 1965	-10.5°C2 Mar 1965	22 mm25 Mar 1996	102 mm1988 · driest 13 mm in 1961	55
April	23.7°C25 Apr 1975	-4.7°C5 Apr 2000	31 mm12 Apr 1961	120 mm1961 · driest 10 mm in 1988	55
May	25.7°C23 May 1989	-2.3°C18 May 1996	20 mm1 May 1983	124 mm1983 · driest 4 mm in 1991	55
June	31.2°C29 Jun 1976	-0.3°C1 Jun 1975	41 mm11 Jun 1993	160 mm1998 · driest 7 mm in 1975	55
July	30.8°C13 Jul 1983	3.1°C17 Jul 1971	45 mm31 Jul 1991	145 mm1960 · driest 12 mm in 1989	55
August	29.4°C17 Aug 1995	1.2°C30 Aug 1964	59 mm2 Aug 1984	178 mm1985 · driest 6 mm in 1976	55
September	26.3°C10 Sep 1959	-1.1°C27 Sep 2007	36 mm20 Sep 2006	147 mm1962 · driest 2 mm in 1986	55
October	23.2°C4 Oct 1959	-5.2°C17 Oct 1993	34 mm11 Oct 1976	147 mm1967 · driest 30 mm in 2003	55
November	17.5°C3 Nov 1979	-7.2°C17 Nov 1972	35 mm1 Nov 1968	152 mm1960 · driest 17 mm in 1957	55
December	15.3°C1 Dec 1985	-9.4°C28 Dec 1961	38 mm8 Dec 1983	180 mm1959 · driest 24 mm in 1963	55

Typical days per month at BIRR, 1991–2020
Month	Days 25°C+	Frost nights	Heavy rain (10 mm+)
January	0	7	2
February	0	8	1
March	0	5	1
April	0	3	2
May	<1	<1	1
June	<1	0	2
July	1	0	1
August	1	0	2
September	<1	<1	2
October	0	2	3
November	0	4	2
December	0	7	2

How often, not how much — every day in BIRR’s record sorted by what it was actually like, rather than averaged
Month	Warm & dry days	Wet days	Washouts	Week with 3+ wet days	Daytime mean has ranged
January	0%	47%	6%	64%	6.5–9.7°C
February	0%	40%	4%	51%	6.0–10.0°C
March	0%	43%	4%	58%	8.7–11.7°C
April	1%	38%	4%	50%	10.9–13.9°C
May	7%	41%	3%	54%	13.6–16.9°C
June	19%	39%	5%	52%	16.5–19.9°C
July	25%	38%	5%	53%	17.7–21.1°C
August	24%	42%	7%	56%	17.7–20.9°C
September	10%	42%	6%	58%	15.7–18.1°C
October	<1%	45%	9%	61%	12.3–15.4°C
November	0%	45%	7%	62%	8.7–11.4°C
December	0%	47%	7%	64%	6.9–9.9°C

A warm and dry day reaches 20°C with under 1 mm of rain; a wet day gets 1 mm or more; a washout gets 10 mm or more. The week column is the share of seven-day stretches in that month, across the station’s whole daily record, that contained three or more wet days — the odds a week-long trip is rained on repeatedly, counted rather than modelled. The last column is the 10th to 90th percentile of that month’s daytime average across individual years: a narrow band means the average is what you will get, a wide one means the average is a midpoint between years that felt quite different.

1955Each stripe is one year’s mean temperature against the 54-year average. Warmest: 2007. Coolest: 1986.2008

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 2962029
NOAA station: EI000003965 · BIRR
Station distance: 46.4 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 18 usable years
Daylight: Calculated from latitude 53.16°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Important limit: Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.

These places read the same station, so their numbers are identical — distance from BIRR is what differs

Portlaoise→Athlone→Tullamore→Nenagh→Thurles→Nenagh Bridge→

Or put two places side by side: Portarlington vs Portlaoise

Best time to visitPortarlington.

July

July

August

The whole year,without the guesswork.

Nearby, measured,and named.

Best time to visit
Portarlington.

The whole year,
without the guesswork.

Nearby, measured,
and named.