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

Weather in Alton, Missouri

Roses open on the Piedmont edge. Day 59 of spring. Read this microseason across nine climate regions →

Alton, MO
Sunday, May 17 at 1:45 AM
75
°
Clear
Feels like
76°
Humidity
69%
Wind
9 mph
Sunrise
5:57 AM
Sunset
8:06 PM
Alton, MO
Hour by hour · 24h
68°
8p
65°
9p
63°
10p
62°
11p
61°
12a
60°
1a
59°
2a
58°
3a
57°
4a
58°
5a
58°
6a
60°
7a
64°
8a
68°
9a
71°
10a
74°
11a
76°
12p
79°
1p
80°
2p
81°
3p
80°
4p
81°
11%
5p
78°
6p
76°
7p
L 57°H 81°
Alton, MO
7-day forecast
  1. Today
    May 16
    Overcast
    25%
    85°73°
  2. Sunday
    May 17
    Partly Cloudy
    87°65°
  3. Monday
    May 18
    Light Drizzle
    27%
    82°73°
  4. Tuesday
    May 19
    Thunderstorm
    68%
    84°62°
  5. Wednesday
    May 20
    Drizzle
    71%
    66°57°
  6. Thursday
    May 21
    Rain
    27%
    62°57°
  7. Friday
    May 22
    Heavy Drizzle
    28%
    71°59°
Alton, MO
Anemometer · 24h winds · from true
NESW
From · True
SSE
156° · backing 18°
Direction
SSE
156°
Sustained
9
mph
Gust
17
mph
Peak 24h
35
avg 11
Beaufort · 3 · GENTLE 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 11 · pk 35 @ 3:00a
−24h−18h−12h−6hnow
Light breeze backing 18° from the sse.
Alton, MO
Barometer · 24h pressure · mb
STORMRAINCHANGEFAIRDRY9901000101010201030
Pressure · mb
984.7
-0.4 mb in 3h · steady · 29.08 inHg
Now
984.7
mb
3h
-0.4
mb
12h
-2.2
mb
24h
+1.2
mb
Regime · STORM
STORM
RAIN
CHANGE
FAIR
DRY
24h · Pressure · mb
range 984987
−24h−18h−12h−6hnow
Deep low — expect rough seas, strong wind, and persistent rain.
Alton, MO
Air quality
57
AQI
Moderate
PM 2.5
4.8 μg/m³
PM 10
6.1 μg/m³
NO₂
0.9 μg/m³
Ozone
112.0 μg/m³
UV Index
0.0 Low
Alton, MO
Almanac · Sunday, May 17
When the dew is on the grass, rain will never come to pass.
Civil dawn
10:29 AM
Sunrise
5:57 AM
Daylight
14h 09m
Sunset
8:06 PM
Civil dusk
1:36 AM
Planting note
Direct sow okra, melons, and southern peas. Thin carrot rows.
Alton, MO
The moon
New Moon
0% illuminated
Moonrise
11:07 AM
Moonset
1:33 AM
In sign
♉︎ Taurus
Alton, MO
Microseason · 28 of 72
May 16–20

Roses open on the Piedmont edge

insect
Jan 137% of the yearDec 31

Read this microseason across nine climate regions →

Alton at a glance

  • Today vs. normal: 75°F — typical for the season
  • Last frost: March 27 (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.

ZIP codes in Alton

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.