Australia · 1991–2020

Best time to visit
Greystanes.

April leads for comfortable weather in Greystanes: typically 24.1°C by day, 12.9°C at night, with 67 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortApril

Typical high24.1°C

Typical low12.9°C

Rain in April67 mm

Comfort

April

April · October · September

88climate match

Beach

January

January · December · February

74climate match

Outdoors

May

May · August · September

92climate match

The weakest month is June, scoring 56 against April’s 88 — days reach only 17.7°C, 6° below the 24°C the score treats as ideal, and nights drop to 7.5°C.

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

6429.3° / 17.9°

Feb

6228.6° / 18°

Mar

7526.7° / 16.2°

Apr

8824.1° / 12.9°

May

7520.6° / 9.6°

Jun

5617.7° / 7.5°

Jul

5817.2° / 6.1°

Aug

6819.3° / 6.6°

Sep

8222.4° / 9.5°

Oct

8624.8° / 12.1°

Nov

8226.1° / 14.4°

Dec

7427.9° / 16.4°

Monthly climate evidence for Greystanes — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 37 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	29.3°C	17.9°C	95 mm	8.4	22.7°C	14 h 10	64	Strong coverage
February	28.6°C	18°C	127 mm	8.7	23.2°C	13 h 22	62	Strong coverage
March	26.7°C	16.2°C	97 mm	9.1	23.1°C	12 h 24	75	Strong coverage
April	24.1°C	12.9°C	67 mm	6.5	22.1°C	11 h 18	88	Strong coverage
May	20.6°C	9.6°C	49 mm	5.3	20.8°C	10 h 24	75	Strong coverage
June	17.7°C	7.5°C	76 mm	7	19.4°C	9 h 55	56	Strong coverage
July	17.2°C	6.1°C	41 mm	5.7	18.4°C	10 h 06	58	Strong coverage
August	19.3°C	6.6°C	39 mm	4.2	17.9°C	10 h 52	68	Strong coverage
September	22.4°C	9.5°C	43 mm	5.2	18.1°C	11 h 56	82	Strong coverage
October	24.8°C	12.1°C	56 mm	6.7	19.0°C	13 h	86	Strong coverage
November	26.1°C	14.4°C	75 mm	8.2	20.0°C	13 h 56	82	Strong coverage
December	27.9°C	16.4°C	76 mm	8.2	21.3°C	14 h 23	74	Strong coverage

Records at PROSPECT RESERVOIR, 1965–2018
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	45.3°C7 Jan 2018	10.0°C16 Jan 1996	161 mm31 Jan 2001	316 mm2016 · driest 5 mm in 1985	54
February	43.3°C11 Feb 2017	10.8°C18 Feb 1998	150 mm3 Feb 1990	456 mm1990 · driest 7 mm in 2000	54
March	39.5°C13 Mar 1998	7.9°C30 Mar 1970	140 mm20 Mar 1978	346 mm1978 · driest 6 mm in 1986	54
April	37.1°C4 Apr 1986	3.6°C23 Apr 2006	140 mm16 Apr 1969	425 mm2015 · driest 2 mm in 1997	54
May	29.4°C10 May 1967	1.2°C29 May 1987	164 mm1 May 1988	197 mm1988 · driest 1 mm in 1973	53
June	25.6°C6 Jun 1997	-0.8°C30 Jun 2010	163 mm11 Jun 1991	300 mm2016 · driest 1 mm in 2001	53
July	27.1°C30 Jul 2017	-0.6°C17 Jul 2007	112 mm6 Jul 1988	144 mm1988 · driest 0 mm in 1977	53
August	29.4°C26 Aug 1995	-0.5°C13 Aug 2005	108 mm2 Aug 1990	203 mm1987 · driest 0 mm in 1995	52
September	34.5°C29 Sep 2000	1.7°C1 Sep 2012	97 mm2 Sep 1970	170 mm1995 · driest 0 mm in 1968	53
October	39.0°C21 Oct 1988	0.0°C31 Oct 2017	62 mm17 Oct 1972	196 mm2004 · driest 0 mm in 1988	53
November	42.0°C20 Nov 2009	0.0°C1 Nov 2017	126 mm14 Nov 1969	237 mm1969 · driest 11 mm in 2002	53
December	42.7°C21 Dec 1994	7.8°C18 Dec 1969	117 mm9 Dec 1970	267 mm1970 · driest 2 mm in 1979	53

Typical days per month at PROSPECT RESERVOIR, 1991–2020
Month	Days 25°C+	Days 30°C+	Heavy rain (10 mm+)
January	24	12	3
February	22	10	3
March	21	6	3
April	11	1	2
May	2	0	2
June	0	0	2
July	<1	0	1
August	1	0	1
September	8	1	1
October	14	5	1
November	16	7	3
December	22	10	3

How often, not how much — every day in PROSPECT RESERVOIR’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	72%	27%	9%	30%	26.2–30.6°C
February	68%	29%	9%	35%	26.0–30.2°C
March	71%	28%	9%	33%	24.9–27.8°C
April	72%	23%	7%	25%	22.1–25.2°C
May	49%	21%	6%	21%	19.2–21.1°C
June	9%	23%	6%	25%	16.2–18.6°C
July	9%	19%	5%	19%	15.9–18.1°C
August	29%	19%	4%	18%	17.3–20.3°C
September	56%	20%	4%	21%	19.3–23.9°C
October	66%	22%	6%	23%	21.9–26.4°C
November	68%	25%	8%	28%	23.3–28.1°C
December	74%	25%	7%	26%	25.2–30.1°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.

1965Each stripe is one year’s mean temperature against the 50-year average. Warmest: 2016. Coolest: 1967.2017

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 8348582
NOAA station: ASN00067019 · PROSPECT RESERVOIR
Station distance: 3.1 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 27 usable years
Daylight: Calculated from latitude -33.82°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 37 km from the place centre. A sheltered bay can run warmer than the open sea it is measured from.
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 PROSPECT RESERVOIR is what differs

Blacktown→Quakers Hill→Seven Hills→Fairfield→Glenwood→Rooty Hill→

Or put two places side by side: Greystanes vs Blacktown

Best time to visitGreystanes.

April

January

May

The whole year,without the guesswork.

Nearby, measured,and named.

Best time to visit
Greystanes.

The whole year,
without the guesswork.

Nearby, measured,
and named.