Skip to content
worldfires
TH · Thailand · →

Pai fire, 7 March 2020 Pai

Out · last detection 13 Mar 2020, 18:35 UTC

The fire started on 7 March 2020 in Pai, Thailand, and satellites saw it burning for 7 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,724 hectares from heat detections, spread across a single municipality.

It is the 313th largest in Mae Hong Son Province since 2016 (of 668 with a page). Number 299 in Thailand in 2020, of 666.

The power measured by the satellite is low (14.7 MW in the strongest hotspot), more typical of grass or stubble burning, or a slow surface fire, than of a large crown fire.

Burnt area
1,724ha
GWIS perimeter (Copernicus)
Duration
7days
7 Mar 2020 – 13 Mar 2020
Municipalities hit
1
districts
Started on
7 Mar
2020
Heat detections
59
in a single hotspot: 15 MW
Danger at start
24
High · FWI index
Energy released
235MW
sum of detected power

Where it burned

13 Mar 2020
HOTSPOTS BY DAY 7 Mar13 Mar

How it evolved, day by day

78910111213

Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.

The weather it burned in

37°high
50km/h · peak gust
21%lowest humidity

It had gone 14 days without rain (1 mm or more) when it started.

This area had burned before

39% of the perimeter overlaps earlier fires recorded since 2016: 37 ha in 2016, 525 ha in 2017, 227 ha in 2018, 72 ha in 2019. Part of it burned more than once, so the yearly figures add up to more than the 665 ha that had burned before.

What happened to each town

  1. Pai where it started
    1,730 ha reached on 7 Mar
    0.8 %

Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance is from the town centre to the nearest fire: staying a kilometre away does not mean it reached the houses.

The weather day by day

ECMWF ERA5 reanalysis at the fire location, the standard reference for past weather, and the Canadian Fire Weather Index (the same system Copernicus uses), computed by WorldFires from that data. Days after the fire run until the first rain.

Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

Day High Min. humidity Peak gust Rain Danger (FWI)
25 Feb 32.1 °C 30 % 19 km/h 0.0 mm High 24
26 Feb 33.0 °C 28 % 25 km/h 0.0 mm High 26
27 Feb 30.5 °C 36 % 24 km/h 0.0 mm High 25
28 Feb 32.5 °C 31 % 31 km/h 0.0 mm High 27
29 Feb 33.6 °C 25 % 37 km/h 0.0 mm High 32
1 Mar 34.5 °C 24 % 35 km/h 0.0 mm High 32
2 Mar 34.4 °C 21 % 37 km/h 0.0 mm High 35
3 Mar 32.7 °C 29 % 45 km/h 0.3 mm High 35
4 Mar 32.0 °C 32 % 36 km/h 0.0 mm High 32
5 Mar 34.0 °C 22 % 36 km/h 0.0 mm High 35
6 Mar 33.4 °C 26 % 47 km/h 0.0 mm Very high 38
7 Mar 34.4 °C 24 % 45 km/h 0.0 mm Very high 38
8 Mar 33.9 °C 26 % 50 km/h 0.0 mm Very high 41
9 Mar 34.4 °C 24 % 45 km/h 0.0 mm Very high 39
10 Mar 35.5 °C 24 % 21 km/h 0.0 mm High 34
11 Mar 36.6 °C 22 % 35 km/h 0.0 mm High 37
12 Mar 36.7 °C 22 % 32 km/h 0.0 mm High 36
13 Mar 37.3 °C 25 % 23 km/h 0.0 mm High 35
14 Mar after 36.9 °C 27 % 19 km/h 0.0 mm High 35
15 Mar after 37.4 °C 26 % 27 km/h 0.0 mm High 37
16 Mar after 36.4 °C 25 % 38 km/h 0.0 mm Very high 39
17 Mar after 36.4 °C 24 % 37 km/h 0.0 mm Very high 39
18 Mar after 36.5 °C 23 % 43 km/h 0.0 mm Very high 42
19 Mar after 36.2 °C 23 % 27 km/h 0.0 mm High 37
20 Mar after 35.8 °C 25 % 40 km/h 0.3 mm Very high 41
21 Mar after 34.5 °C 27 % 47 km/h 0.2 mm Very high 44
22 Mar after 34.1 °C 27 % 43 km/h 0.7 mm High 33
23 Mar after 34.5 °C 24 % 41 km/h 0.0 mm Very high 38

Before and after, from space

Drag the line to compare the same ground before the fire and after it.

Before · 29 Feb 2020
After · 20 Mar 2020

If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.

Detections table · 59Every satellite heat detection, one by one, with time, satellite, power and coordinates.
⬇ Download CSV Times in UTC. Each detection is a 375 m pixel: a large fire yields hundreds per pass.
Date and timeSatelliteFRP (MW)LatLon

Other fires nearby

All fires in Thailand ›

Frequently asked questions

How long did the Pai fire last?
GWIS (Copernicus) dates it between 7 March 2020 and 13 March 2020: 7 days between the first and last heat detection of the perimeter.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 1,724 hectares (17.2 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire only entered Pai (1,730 ha, 0.8 %).
What was the weather like?
During the fire the temperature reached 37.3 °C, humidity dropped to 21 % and gusts hit 50 km/h. The fire danger index (FWI) reached 41, class Very high.
Where does this data come from?
From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Thailand (geoBoundaries). It is not an official report.

Where to verify it

A satellite detection is not an official report. Final figures and the fire’s status are published by each country’s emergency service.

Emergency number: 199 · 191

Satellite cross-check

Does something look wrong on this page?

This page is built from satellite data and official records, and it sometimes gets things wrong: the wrong dates, the wrong town, two fires merged into one, or something that was not a wildfire at all. If you know this fire first-hand (you live nearby, saw it, fought it or reported on it), tell us what really happened and we will check it.

Report an error
What do you think is wrong?

We will only use your email to reply about this report. Privacy. This is not an emergency service: if there is a fire now, call 199 · 191.

Where this data comes from

The perimeter comes from the Copernicus Global Wildfire Information System (GWIS), which rebuilds it from MODIS and VIIRS heat detections and publishes it under CC BY 4.0. It is not measured on imagery as in Europe, so it is an estimate. Heat detections come from the VIIRS sensors aboard Suomi-NPP and NOAA-20, distributed by NASA FIRMS at 375 m resolution. Municipal boundaries come from geoBoundaries ADM2 (Creative Commons Attribution 3.0 Intergovernmental Organisations (CC BY 3.0 IGO)). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ from each country’s official figure.