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TH · Thailand · –

Na Noi fire, 15 March 2019 นาน้อย · Na Noi, Wiang Sa

Out · last detection 17 Mar 2019, 18:22 UTC

The fire started on 15 March 2019 in Na Noi, Thailand, and satellites saw it burning for 6 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 1,010 hectares from heat detections, spread across 2 municipalities.

It is the 153th largest in Nan Province since 2016 (of 157 with a page). Number 376 in Thailand in 2019, of 385.

The power measured by the satellite is low (17.0 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
1,010ha
GWIS perimeter (Copernicus)
Duration
6days
15 Mar 2019 – 20 Mar 2019
Municipalities hit
2
districts
Started on
15 Mar
2019
Heat detections
26
in a single hotspot: 17 MW
Danger at start
32
High · FWI index
Average daily power
28MW
detected power per day, on average

Where it burned

HOTSPOTS BY DAY 15 Mar20 Mar
17 Mar 2019

How it evolved, day by day

15 Mar 2019 · 33 MW · 11 16 Mar 2019 · 35 MW · 12 17 Mar 2019 · 16 MW · 3
15 Mar 16 Mar 17 Mar

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
38km/h · peak gust
27%lowest humidity

It had gone 25 days without rain (1 mm or more) when it started. Rain came after the fire: 2.5 mm on 27 Mar.

This area had burned before

79% of the perimeter overlaps earlier fires recorded since 2016: 19 ha in 2016, 413 ha in 2017, 619 ha in 2018. Part of it burned more than once, so the yearly figures add up to more than the 793 ha that had burned before.

How big is it?

10 km
It burned the equivalent of 0.6% of the area of London (10 km² against 1,583 km²).

London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).

This compares size, not location: both shapes are at the same scale, north up, centred on each other.

What happened to each town

  1. Na Noi นาน้อย where it started
    709 ha reached on 15 Mar
    0.6 %
  2. Wiang Sa เวียงสา
    307 ha reached on 15 Mar
    0.2 %

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

People and buildings inside the perimeter

GHSL 2020
Built-up area< 0.1 ha
Residents< 20

Inside the perimeter there was no noticeable built-up land and almost nobody lived there (GHSL 2020, satellite-based estimate).

This is an estimate on 100 m cells, made from satellite imagery and census data: it does not mean that homes burned or that anyone was harmed. The perimeter also contains land that never burned.

Source: Global Human Settlement Layer (GHS-BUILT-S and GHS-POP R2023A), European Commission Joint Research Centre (JRC), © European Union, CC BY 4.0. Sum inside the perimeter computed by WorldFires. human-settlement.emergency.copernicus.eu

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)
15 Mar 35.8 °C 33 % 22 km/h 0.0 mm High 32
16 Mar 35.7 °C 38 % 36 km/h 0.1 mm High 31
17 Mar 36.2 °C 37 % 28 km/h 0.0 mm High 28
18 Mar 36.0 °C 36 % 27 km/h 0.9 mm High 23
19 Mar 36.2 °C 35 % 38 km/h 3.3 mm Moderate 13
20 Mar 37.1 °C 27 % 36 km/h 0.0 mm High 30
21 Mar after 38.2 °C 23 % 24 km/h 0.0 mm High 32
22 Mar after 37.8 °C 24 % 23 km/h 0.0 mm High 32
23 Mar after 38.3 °C 23 % 16 km/h 0.0 mm High 31
24 Mar after 36.5 °C 34 % 39 km/h 0.0 mm High 35
25 Mar after 36.4 °C 41 % 35 km/h 0.0 mm High 31
26 Mar after 36.2 °C 40 % 30 km/h 0.8 mm High 23
27 Mar after 34.9 °C 41 % 34 km/h 2.5 mm Moderate 11

Its twins: fires that started in the same weather

It started with an FWI of 31.6, a minimum humidity of 33% and 25 days without rain. Fires in the area that started in weather like this since 2016: 30.

FWI at the start 31.6
Minimum humidity 33 %
Days without rain 25
this fire chosen twins rest of the area
Almost identicalSimilar

Outlines of the closest twins

Wang Chin fire, March 2016
2,238 ha 12 days FWI 32.1 Min. humidity 34 % 127 km away, in 2016

First rain (1 mm or more) after it ended: 3.0 mm on 2 Apr.

What happened to them

8 days
median duration
1,305 ha
median area
100 %
went past 1,000 ha
3.1 mm
rain at the end (median; 17 of 30 had it)

It burned an area similar to its twins (1,010 ha against a median of 1,305 ha) and lasted 6 days, against 8 days.

In 13 of 30, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 3.1 mm.

This is a bank of analogues: it shows what usually happens, not what will happen. With fewer than 15 twins we give no figures. How we calculate it

How it ended

2.5 mmfirst rain
27 Mar7 days after it ended
38km/h · max. gust

It was considered over on 20 Mar, and on 27 Mar 2.5 mm fell. We do not know whether the rain or the firefighters put it out. Twins with rain when they ended: 17 of 30, with a median of 3.1 mm.

Weather on this page: Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)

How a twin is chosen

  • Same area: fires that have already ended, less than 250 km from this one, since 2016.
  • Same start: we compare the FWI on the first day, the minimum humidity that day and the run of days without rain before it. The slider sets how much they may differ.
  • Only pages with final weather data (ERA5 reanalysis) calculated in the same way as this fire’s; agricultural and grass burns and pages with data under review are left out.
  • Fires burning at the same time as this one (a week before or after) are left out: they share the same spell of weather and do not count as a precedent.
  • They are sorted by similarity, and the outlines of the first five are drawn.

How we calculate it

Before and after, from space

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

Before · 8 Mar 2019
After · 27 Mar 2019

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 · 26Every 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 Na Noi fire last?
According to the heat detections seen by satellite inside the perimeter, it burned from 15 March 2019 to 20 March 2019 (6 days). The perimeter dates it from 15 March 2019 to 17 March 2019.
How much area did it burn?
The perimeter GWIS (Copernicus) rebuilt from heat detections is 1,010 hectares (10.1 km²). It is an estimate: official national figures may differ.
Which municipalities burned?
The fire entered 2 municipalities: Na Noi (709 ha, 0.6 %); Wiang Sa (307 ha, 0.2 %).
What was the weather like?
During the fire the temperature reached 37.1 °C, humidity dropped to 27 % and gusts hit 38 km/h. The fire danger index (FWI) reached 32, class 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.
How did the fires that started in similar weather in this area end?
Fires less than 250 km away that started since 2016 with a similar FWI, humidity and dry spell: 30. Their median duration was 8 days and their median area 1,305 ha; 100 % went past 1,000 ha. In 13 of 30, not even 1 mm fell in the ten days after the end: they went out without rain. In the rest, the first rainy day brought a median of 3.1 mm.

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 · Emergency number and official warnings

Satellite cross-check

History of this page · 1 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
  1. Last day with fire: 17 March 2019 → 20 March 2019.

RSS Changes to this page With cross-checks and a citable version

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.

How we know this
  • Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
  • Dates adjusted with the VIIRS detections inside the perimeter, which said 15 March 2019 to 17 March 2019. 26 Suomi-NPP VIIRS detections on those dates.
  • We have not matched this page with any official record.
  • Weather: Copernicus ERA5 reanalysis at the fire location, in cells of about 25 km.
  • Built-up area and population come from the JRC Global Human Settlement Layer (epoch 2020, 100 m cells), summed inside the perimeter: an estimate of what was there, not a damage count.

How we build fire pages: methodology

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.