Soundings › Sterling (Washington)
Sterling (Washington), VA weather balloon
Launch of 2026-10-28 00Z (evening launch, US time) · ground level 305 ft above sea level, 62°F at launch
What it means
Freezing level about 12,900 ft up
Rain stays rain at the ground. Hail has less warm air to melt in, so hail from strong storms can reach the ground bigger.
Air is trapped near the ground (inversion up to about 200 ft)
It is 5°F warmer a few hundred feet up than at the ground. Smoke, dust and exhaust stay low, fog is more likely when it's humid, and sound carries farther. On a sunny day it usually mixes out by late morning, and winds at the ground pick up when it does.
Wind at crane height: 5 mph from the E
At about 260 ft the wind was 5 mph, against 3 mph at the ground: 1.6 times stronger. Wind at height is often much stronger than at the ground, especially at night and in the morning. Many outdoor aerial lifts are rated for winds up to 28 mph; crane limits depend on the crane and the load, so check its manual.
Little storm fuel
Air lifted from near the ground doesn't rise on its own, so thunderstorms are unlikely from this air (things can change by afternoon or as a front arrives).
0.96 inches of water in the air
About average moisture. Rain amounts would be modest unless a big storm system arrives.
Temperature and moisture by height
Temperature Dew point Freezing (32°F)
Heights are above the ground. The closer the two lines, the more humid; where they touch, there's cloud.
Wind by height
| At the ground | ESE 3 mph |
|---|---|
| About 260 ft (crane and lift height) | E 5 mph |
| 1,000 ft | ENE 6 mph |
| 3,000 ft | NNW 3 mph |
| 5,000 ft | NW 16 mph |
| 10,000 ft | WNW 13 mph |
| 18,000 ft | W 20 mph |
| 30,000 ft | W 26 mph |
Direction is where the wind comes from.
- Storm fuel (CAPE)
- 0 J/kg
- Wind change, ground to 20,000 ft
- 30 mph
- Water in the air
- 0.96 in
- Freezing level
- 12,900 ft
About soundings
Balloons go up at about 6 a.m. and 6 p.m. Central time (12Z and 00Z) and take about 2 hours to climb. The numbers show what the air was doing at launch, so they are a snapshot, not a forecast. Conditions change through the day, especially in the afternoon and when a front passes.
Wind at crane height is the measured wind about 260 ft (80 m) up. Storm fuel (CAPE) is how strongly a rising bubble of air would keep rising. Wind change with height (shear) helps storms last and turn severe. Water in the air (precipitable water) is how much rain the whole column would make if it all fell. Notes like these are a planning aid, not an official forecast or warning. For warnings, follow the National Weather Service.
Want this for a job? AtmosDays Plus and Pro show the HRRR model's hour-by-hour wind at crane height for each jobsite, for the next 2 days. See how it works.
Data: NOAA National Weather Service upper-air sounding, via Iowa State University's Iowa Environmental Mesonet. Explanations by AtmosDays; storm fuel is for the most unstable air in the lowest 10,000 ft or so.