🇺🇲 United States Minor Outlying Islands
National FlagGeography & Borders
This country has no land borders.
Introduction & Background
The United States Minor Outlying Islands is a statistical designation defined by the International Organization for Standardization's ISO 3166-1 code. The entry code is ISO 3166-2:UM. The minor outlying islands and groups of islands consist of eight United States insular areas in the Pacific Ocean (Baker Island, Howland Island, Jarvis Island, Johnston Atoll, Kingman Reef, Midway Atoll, Palmyra Atoll, and Wake Island) and one in the Caribbean Sea (Navassa Island).
In 1936, a colonization program began to settle Americans on Baker, Howland, and Jarvis, but all three islands were evacuated in 1942 as a result of World War II.12
Geography & Climate
Climate, weather, and air quality data are based on historical records for the geographical center coordinates.
Temperature (2025)
15°25°35°
Jan
25.8° / 27.3°
Feb
25.1° / 26.5°
Mar
24.7° / 26.3°
Apr
25.4° / 26.8°
May
25.4° / 27.2°
Jun
26.1° / 28.2°
Jul
26.2° / 28.4°
Aug
27° / 28.9°
Sep
26.3° / 29.1°
Oct
26.3° / 28.9°
Nov
26.8° / 28.2°
Dec
25.2° / 26.8°
Precipitation & Snow (2025)
Rain (mm) Snow (cm)
Atmospheric Pressure (2025)
1015.1+0.7Jan
1014-0.4Feb
1015.9+1.5Mar
1015.6+1.2Apr
1014.7+0.3May
1014.6+0.2Jun
1014.2-0.2Jul
1013.9-0.5Aug
1013.6-0.8Sep
1014.3-0.1Oct
1013.9-0.5Nov
1012.9-1.5Dec
Thunderstorm Days (2025)
0Jan
0Feb
0Mar
0Apr
0May
0Jun
0Jul
0Aug
0Sep
0Oct
0Nov
0Dec
Wind Speed (2025)
Air Quality — Monthly Averages (2025)
| Metric | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 μg/m³ | 6.9 | 6.5 | 7.9 | 8.1 | 6.2 | 6 | 6.8 | 6.1 | 4.7 | 6.4 | 6.4 | 7.2 |
| PM10 μg/m³ | 11.2 | 10.6 | 13.1 | 13.9 | 10.6 | 9.8 | 10.9 | 9.6 | 7.7 | 10.6 | 10.6 | 11.9 |
| O₃ μg/m³ | 74.9 | 78.2 | 73.3 | 68 | 52.4 | 38.3 | 39.4 | 33.9 | 36.3 | 48.2 | 56 | 84 |
| NO₂ μg/m³ | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| SO₂ μg/m³ | 0.2 | 0.1 | 0.2 | 0.1 | 0.1 | 0.1 | 0.1 | 0.2 | 0.1 | 0.1 | 0.1 | 0.2 |
| CO μg/m³ | 119 | 151 | 133 | 130 | 115 | 97 | 89 | 80 | 88 | 101 | 106 | 125 |
Pollen Levels — Monthly (2025)
Pollen data is negligible or unavailable for this location.
⛰️ Highest Elevation
Unnamed hill on Sand Island (Johnston Atoll)13 m / 43 ft
- Map Locations: Google Maps | OpenStreetMap
People & Society
Total PopulationN/A
Annual Growth RateN/AN/A
Life ExpectancyN/AAverage lifespan at birth
Fertility RateN/ABirths per woman