Weather StoryAlmanac, microseasons, and the day's weather story.

Weather in Diamond Bar, California

Fog and sun in daily rhythm. Day 58 of spring. Read this microseason across nine climate regions →

Diamond Bar, CA
Saturday, May 16 at 11:59 PM
69
°
Partly Cloudy
Feels like
65°
Humidity
61%
Wind
13 mph
Sunrise
5:48 AM
Sunset
7:46 PM
Diamond Bar, CA
Hour by hour · 24h
74°
4p
73°
5p
71°
6p
68°
7p
64°
8p
62°
9p
60°
10p
59°
11p
57°
12a
56°
1a
55°
2a
54°
3a
57°
4a
58°
5a
58°
6a
58°
7a
59°
8a
59°
9a
60°
10a
62°
11a
65°
12p
66°
1p
70°
2p
72°
3p
L 54°H 74°
Diamond Bar, CA
7-day forecast
  1. Today
    May 16
    Overcast
    74°55°
  2. Sunday
    May 17
    Overcast
    74°55°
  3. Monday
    May 18
    Overcast
    80°49°
  4. Tuesday
    May 19
    Overcast
    85°60°
  5. Wednesday
    May 20
    Overcast
    82°62°
  6. Thursday
    May 21
    Overcast
    80°61°
  7. Friday
    May 22
    Clear
    82°62°
Diamond Bar, CA
Anemometer · 24h winds · from true
NESW
From · True
WSW
237° · backing 14°
Direction
WSW
237°
Sustained
13
mph
Gust
16
mph
Peak 24h
16
avg 6
Beaufort · 4 · MOD BRZ
0
CALM
<1
1
LIGHT AIR
1–3
2
LIGHT BRZ
4–7
3
GENTLE BRZ
8–12
4
MOD BRZ
13–18
5
FRESH BRZ
19–24
6
STRONG BRZ
25–31
7
NEAR GALE
32–38
24h · sust vs gust · mph
avg 6 · pk 16
−24h−18h−12h−6hnow
A fresh breeze drives the wsw-bound air across the harbor.
Diamond Bar, CA
Barometer · 24h pressure · mb
STORMRAINCHANGEFAIRDRY9901000101010201030
Pressure · mb
974.6
+0.6 mb in 3h · falling · 28.78 inHg
Now
974.6
mb
3h
+0.6
mb
12h
-2.2
mb
24h
-2.3
mb
Regime · STORM
STORM
RAIN
CHANGE
FAIR
DRY
24h · Pressure · mb
range 973977
−24h−18h−12h−6hnow
Deep low — expect rough seas, strong wind, and persistent rain.
Diamond Bar, CA
Air quality
57
AQI
Moderate
PM 2.5
15.3 μg/m³
PM 10
23.9 μg/m³
NO₂
3.9 μg/m³
Ozone
122.0 μg/m³
UV Index
3.5 Moderate
Diamond Bar, CA
Almanac · Saturday, May 16
Flowers blooming in late autumn, a sure sign of a bad winter coming.
Civil dawn
12:22 PM
Sunrise
5:48 AM
Daylight
13h 58m
Sunset
7:46 PM
Civil dusk
3:15 AM
Planting note
Direct sow okra, melons, and southern peas. Thin carrot rows.
Diamond Bar, CA
The moon
New Moon
0% illuminated
Moonrise
12:18 PM
Moonset
2:03 AM
In sign
♉︎ Taurus
Diamond Bar, CA
Microseason · 28 of 72
May 16–20

Fog and sun in daily rhythm

weather
Jan 137% of the yearDec 31

Read this microseason across nine climate regions →

Diamond Bar at a glance

  • Today vs. normal: 9°F below the seasonal normal for this latitude
  • Last frost: March 11 (climatological average for this latitude)
  • Microseason: 28 of 72, May 16–20
  • Planting window: Direct sow okra, melons, and southern peas. Thin carrot rows.

Right now in the garden

Peak growing season

As of May 16, the growing season is at its peak — frost is months away. Continue succession-planting beans and summer squash. Start fall brassicas (broccoli, cabbage, kale) from seed indoors for transplanting in late summer.

ZIP codes in Diamond Bar

Climate normals from the Open-Meteo Climate API. Köppen approximation from NOAA NCEI U.S. Climate Regions. See methodology for data sources, editorial rules, and corrections. Maintainer: Brian Tighe.