About GOES-R Data

GOES stands for Geostationary Operational Environmental Satellite — NOAA weather satellites that hover over one region of Earth, matching the planet’s rotation so they can watch the same area around the clock. GOES-R is the current generation of those satellites (GOES-16, 17, 18, 19, and so on). Each GOES-R satellite carries several instruments; one of them is the GLM, the Geostationary Lightning Mapper.

Open Bolt shows lightning data from GLM — not weather images or other GOES products — collected by the GOES-R satellites in orbit today. You can search this public data by place and time to see where lightning was detected.

Why track lightning from space?

Severe storms often produce a burst of lightning before they turn dangerous. GLM is the first lightning mapper flown in geostationary orbit, so it can watch an entire hemisphere continuously and help forecasters spot that activity early — during hurricanes, tornado outbreaks, and fast-moving thunderstorms. That extra lead time matters for warnings, aviation, and anyone working outdoors.

Where can GLM see lightning?

NOAA runs two GOES-R satellites as a team: GOES East (GOES-19) and GOES West (GOES-18). Together they watch the Western Hemisphere — the Americas, nearby oceans, and surrounding regions. They do not cover Europe, Africa, or most of Asia.

In practice, Open Bolt can search roughly between 55° south and 55° north latitude. Northern Canada and most of Alaska fall outside GLM’s view. Depending on the date you search, results may come from GOES-16 or GOES-17 as well as the current East and West satellites.

How accurate is a pin on the map?

GLM detects brief flashes of light from storms. Each pin on the map marks the best estimate of where a flash occurred — usually within a few kilometers. The system is designed to place flashes within about 5 km, and in practice often does better (around 3–5 km). That is good for answering “was there lightning near here?” but not “which exact backyard?”

The location is based on light seen from cloud height, not necessarily where a bolt hits the ground. Learn more in NOAA’s GLM performance guide.

What am I looking at?

Each search result is one lightning flash — a burst of activity that can include multiple bolts, not a single ground strike. Here is what the fields mean:

• Time — when the flash was detected, shown in the timezone you selected for your search
• Coordinates — estimated flash location
• Energy — how bright or intense the flash was; useful for comparing flashes to each other, not the same as ground-based lightning sensors

Results match the date and time range you entered — that range is interpreted in your selected timezone, then matched against satellite data. If you export CSV, the time_utc column is always in UTC (Coordinated Universal Time), regardless of the timezone shown on screen.

Open Bolt’s default search uses a 5 km radius around your point, which fits the location uncertainty above. GLM can miss some lightning (especially in daylight) and may not always agree with ground-based networks.

Sources

• NOAA GOES-R GLM Level 2 data — U.S. public domain lightning flash records, hosted on AWS
• NOAA geostationary satellites — which satellites are operating today

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