Satellite before and after

Storm Daniel 2023: floods on the Thessaly plain, Greece

A stalled storm dropped heavy rain on central Greece from 4 to 7 September 2023 and flooded Thessaly, the country's agricultural heartland. The same storm went on to cause the Derna dam floods in Libya.

Thessaly plain around Larissa, central Greece · 4 to 7 September 2023 · Flood · Greece

Compare the imagery

Drag the divider, or focus it and use the arrow keys. Left of the divider is 29 Aug 2023, right is 10 Sep 2023, 12 days apart.

The interactive comparison needs JavaScript. Both images are shown below.

In this false-colour view water is dark blue to black, vegetation is bright green, bare ground is tan, freshly burned land is red-brown and cloud is cyan.

The two images

Satellite image of Thessaly plain around Larissa, central Greece on 29 Aug 2023, before the event, in false colour (MODIS bands 7-2-1).
Before: Aqua, 29 Aug 2023 · Open in NASA Worldview · original from GIBS
Satellite image of Thessaly plain around Larissa, central Greece on 10 Sep 2023, after the event, in false colour (MODIS bands 7-2-1).
After: Aqua, 10 Sep 2023 · Open in NASA Worldview · original from GIBS

What the images show

On 29 August the plain is green and tan farmland. On 10 September long dark-blue bodies of water lie across the western and northern parts of the plain, where there were fields.

About the event

  • NASA Earth Observatory reported that the four-day storm dropped 910 millimetres of rain on central parts of Greece.
  • The storm was a cut-off low: a low-pressure system separated from the jet stream, which stalls in place.

Limits of this comparison

Both images are from the same satellite and layer. The 10 September image is three days after the rain stopped, so the water had already started to move and recede.

Each image is one satellite pass at about 250 metres a pixel. It shows where water or burned land is visible from space on that day; it does not measure damage, and cloud or haze can hide what is underneath.

Dates were chosen by checking the imagery on both satellites for several days either side and keeping the clearest pass. Both use the same layer, MODIS Corrected Reflectance, bands 7-2-1.

Sources

We acknowledge the use of imagery provided by services from NASA's Global Imagery Browse Services (GIBS), part of NASA's Earth Science Data and Information System (ESDIS). Comparison slider: leaflet-side-by-side (MIT licence). Case last updated 12 Sep 2026.

Questions

What does the satellite image of Thessaly plain around Larissa, central Greece show?

On 29 August the plain is green and tan farmland. On 10 September long dark-blue bodies of water lie across the western and northern parts of the plain, where there were fields.

When were the two satellite images taken?

The before-image was taken by Aqua, 29 Aug 2023 and the after-image by Aqua, 10 Sep 2023, 12 days apart.

What can this before-and-after comparison not show?

Both images are from the same satellite and layer. The 10 September image is three days after the rain stopped, so the water had already started to move and recede. Each image is one satellite pass at about 250 metres a pixel. It shows where water or burned land is visible from space on that day; it does not measure damage, and cloud or haze can hide what is underneath.

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