Weather in Boulder, Colorado
High country wildflowers peak. Day 59 of spring. Read this microseason across nine climate regions →
Boulder, CO
Sunday, May 17 at 3:42 AM
66
°
Partly Cloudy
Feels like
61°
Humidity
33%
Wind
5 mph
Sunrise
5:44 AM
Sunset
8:10 PM
Boulder, CO
Hour by hour · 24h
77°
9p
75°
10p
71°
11p
69°
12a
64°
1a
62°
2a
61°
3a
59°
4a
58°
5a
58°
6a
61°
7a
67°
8a
73°
9a
78°
10a
78°
11a
83°
12p
82°
1p
84°
2p
84°
3p
83°
4p
83°
5p
80°
6p
78°
7p
78°
8p
Boulder, CO
7-day forecast
- TodayMay 16Light Drizzle23%79°59°
- SundayMay 17Heavy Drizzle51%69°52°
- MondayMay 18Light Snow Shwrs100%50°34°
- TuesdayMay 19Light Snow85%48°27°
- WednesdayMay 20Overcast80%66°38°
- ThursdayMay 21Heavy Drizzle52%58°45°
- FridayMay 22Overcast28%70°42°
Boulder, CO
Next 24 hours · Mild now
Boulder, CO
Anemometer · 24h winds · from true
From · True
WNW
286° · backing 29°
Direction
WNW
286°
Sustained
5
mph
Gust
7
mph
Peak 24h
18
avg 6
Beaufort · 2 · LIGHT 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
−24h−18h−12h−6hnow
Boulder, CO
Air quality
79
AQI
Moderate
- PM 2.5
- 6.7 μg/m³
- PM 10
- 7.8 μg/m³
- NO₂
- 12.9 μg/m³
- Ozone
- 84.0 μg/m³
- UV Index
- 0.0 Low
Boulder, CO
Almanac · Sunday, May 17
When the dew is on the grass, rain will never come to pass.
Civil dawn
11:15 AM
Sunrise
5:44 AM
Daylight
14h 26m
Sunset
8:10 PM
Civil dusk
2:42 AM
Planting note
Direct sow okra, melons, and southern peas. Thin carrot rows.
Boulder, CO
The moon
New Moon
0% illuminated
- Moonrise
- 11:52 AM
- Moonset
- 2:44 AM
- In sign
- ♊︎ Gemini
Boulder, CO
Microseason · 28 of 72
May 16–20
High country wildflowers peak
bird
Boulder at a glance
- Today vs. normal: 6°F below the seasonal normal for this latitude
- Last frost: April 16 (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
Warm-season window is open
As of May 17, the last spring frost has passed for most years. Transplant tomatoes, peppers, eggplants, basil, and cucurbits (cucumbers, squash, melons) now. Direct-sow beans and corn into warm soil.