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Full catalog/wwllnmth
wwllnmth·v1·dataset

Where thunderstorms struck each month, from lightning

World Wide Lightning Location Network (WWLLN) Monthly Thunder Hour Data
atmosphere NASA GHRC_DAAC Level 3 netCDF-4
In plain English

What it measures. Counts 'thunder hours' each month at points worldwide, meaning the number of hours in which lightning struck close enough that thunder could have been heard nearby. It is a measure of how often thunderstorms occur.

How it's made. Built from a ground-based global lightning detection network (WWLLN), tallying nearby lightning strokes onto a fine map grid from 2013 onward.

How & where you'd use it. Useful for mapping thunderstorm frequency around the world and tracking it over time, with a metric designed to stay comparable even where detection coverage differs.

What's measured

ATMOSPHERE › ATMOSPHERIC ELECTRICITY › LIGHTNINGATMOSPHERE › ATMOSPHERIC ELECTRICITY › LIGHTNING › THUNDER HOUR

Coverage & cadence

  • Time span2013-01-01 → 2025-12-31
  • Measured byWWLLN (VLF RECEIVERS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsnetCDF-4
  • StatusCOMPLETE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

The World Wide Lightning Location Network (WWLLN) has monitored global lightning since late 2004. Since 2013, the number of global WWLLN sensors has remained largely consistent. This WWLLN Monthly Thunder Hour dataset is calculated from lightning detections from 1 January 2013 onward and is an ongoing dataset. A thunder hour is an hour during which thunder can be heard at a given location. Thunder hours represent a historical measure of lightning occurrence and a metric of thunderstorm frequency that is comparatively less sensitive to geographic variations in the detection capabilities of a lightning location system. Thunder hours are the number of hours in a given month during which at least two WWLLN strokes were observed within 15 km of each grid point. Each file includes the monthly accumulated thunder hours for one year. The data are provided at 0.05° latitude and longitude resolution.

Get the data

wwllnmth_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="wwllnmth",
    version="1",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from GHRC_DAAC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.