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Re: Fire Weather - pwsFWI
Posted: Thu 11 Aug 2022 11:26 am
by watsonm
Hans,
Many thanks for the explanation and the link to
https://effis.jrc.ec.europa.eu/apps/eff ... situation/.
It does seem to match (once I realised the colour bands were not identical....

)
(Yes I had read the WIKI stuff)
Re: Fire Weather - pwsFWI
Posted: Fri 12 May 2023 7:23 am
by HansR
It has been a long time since I posted in this thread, but with the Fires in Alberta (Canada) it seems time for another post. It is a pity there is no station there to show the conditions but what we do have is the
the smoke which now should show up around @PaulMy in Komoka. See his AirLink charts which still seem low to what can be expected from the image in the link above.
Re: Fire Weather - pwsFWI
Posted: Sat 13 May 2023 1:59 pm
by PaulMy
Can't say that I have seen anything significantly different here as far as haziness and air quality over the past week or two.
Other than spring may finally be here, and 10 days without rain.
Enjoy,
Paul
Re: Fire Weather - pwsFWI
Posted: Sat 13 May 2023 3:15 pm
by HansR
PaulMy wrote: ↑Sat 13 May 2023 1:59 pm
Can't say that I have seen anything significantly different here as far as haziness and air quality over the past week or two.
Other than spring may finally be here, and 10 days without rain.
Enjoy,
Paul
OK. So far for the remote sensing

Must be in higher regions then.
Re: Fire Weather - pwsFWI
Posted: Tue 30 May 2023 9:02 am
by rogerthn
Hi
According to
SMHI the risk of forest fires is high or very high in my area.
According to
CumulusUtils the risk is somewhat lower.
It has been dry but not that warm, maybe higher temperatures is needed for higher pwsFWI?
Re: Fire Weather - pwsFWI
Posted: Tue 30 May 2023 10:08 am
by HansR
Hi Roger,
Your SMHI apparently uses a binary system (Risk / No Risk; just like in the Netherlands btw) while CUtils uses the widely used 5 scale warning system and the European EFFIS uses a 7 scale warning system.
The binary warning system is used to avoid confusion with the public.
The five level scale (sometimes extended with a sixth purple scale (catastrophic) in Australia on the high risk end) comes from the widely used
Canadian FWI. The levels in interpretation is what is also used with
pwsFWI though the calculation of these levels is totally different.
The European
EFFIS uses all technology available (satellites, meteorology etc...) to play the organ of warnings and they use an unusual 7 level index. (Tick Fire Danger Forecast on the left, click the lowest button on the right for the legend).
For your region EFFIS comes to low/moderate danger and pwsFWI with the blue level comes to moderate. I would say both are saying a similar thing.
The Swedish SMHI with the binary warning level actually cannot be compared with the existing indexes. Binary systems just aim to publicity to keep the public alert and have nothing to do with any form of differentiation between actual phases in the field.
Please also note that fire weather indices can be very local, especially in hills and mountainous terrain: valleys have a tendency to be more moist than the higher slopes and also upwinds on the slopes may favour wildfires. That is why I put a circle of 25 km around the PWS. Strictly speaking the pwsFWI is valid only within that area (maybe even smaller).
And yes, an increasing temperature would increase the value of pwsFWI, just as a higher windspeed, longer dryness and lower RH would. The Vapour Pressure Deficit (VPD) - which is the driving force behind the pwsFWI - depends on those variables (not lineair).
Hope this helps.
Re: Fire Weather - pwsFWI
Posted: Tue 30 May 2023 12:19 pm
by rogerthn
HansR wrote: ↑Tue 30 May 2023 10:08 am
...
Hope this helps.
It did!
Thanks!!
Re: Fire Weather - pwsFWI
Posted: Thu 01 Jun 2023 5:31 am
by HansR
Oh yes,
wildfire exists even in the Highlands (near Cannich). You don't need to be in Siberia or Spain.
The
UK's most northern CUtils installation unfortunately is too far away.
Note this is a peat bog and shrub fire and EFFIS has only a low warning level. Hillside peat bogs and shrublands are difficult to interpret. Gorse shrub burns easily and once ignited peat continues the fire.
Screenshot of EFFIS with warning levels and last 7 days fires enabled:
Re: Fire Weather - pwsFWI
Posted: Fri 09 Jun 2023 5:01 pm
by HansR
And note that the long period dry weather record has been broken on my own station (it is now 23 days and counting) and the other factors are getting favourable as well. In short, the pwsFWI is rising (very rare for my station) and for many other stations in NW Europe:
Schermafbeelding 2023-06-09 170316.png
Re: Fire Weather - pwsFWI
Posted: Fri 09 Jun 2023 8:59 pm
by PaulMy
I don't recall ever being in the Very High and Extreme range, until the last little while...
Enjoy,
Paul
Re: Fire Weather - pwsFWI
Posted: Sat 10 Jun 2023 4:14 am
by HansR
PaulMy wrote: ↑Fri 09 Jun 2023 8:59 pm
I don't recall ever being in the Very High and Extreme range, until the last little while...
Interesting (and worrying) to see it turn red in places where it usually doesn't.
A memorable year already

(and some time to go)
Re: Fire Weather - pwsFWI
Posted: Thu 07 Sep 2023 8:45 am
by HansR
Please note that Windy now has a (free)
Fire Warning Layer as well.
Though somewhat different, It looks pretty good. Australia looks somewhat strange to me - the centre of Australia has little fuel so it could be shown as the Sahara - although the stations using the CUtils pwsFWI seem to be conform. It seems also to be based on the
Canadian FWI - it may be useful to study this. So now there are three easy website warning systems available for Personal Weather Stations:
- pwsFWI of CUtils (this thread) giving real local warning
- The European EFFIS (by Copernicus)
- Windy.com (see link above)
Re: Fire Weather - pwsFWI
Posted: Sun 05 Nov 2023 9:31 am
by HansR
Interesting situation in the early fire season in Australia.
@Phil23 notified me recently the fire season in Australia had an early start.
I checked with
bushfire.io around Perth (see screenshot below, see also a zoom out map) where some sites with pwsFWI are located. Then I checked
the two sites
with pwsFWI (Willeton and Roleystone, roughly 25 km north of where the big fires are) over there and got the following statuses (screenshots) as below. Obviously the Roleystone - 150m altitude in an east sheltered valley - pwsFWI has no idea about the fire situation, while the coastal but urban station - urban, sea wind exposed altitude 17 m - has a pwsFWI value we are expecting. Local conditions are dominating the situation. Take care.
[EDIT:] NOTE that Roleystone has the BOM warning status aabove the pwsFWI table... they have similar status!
2023-11-05 Willeton.png
2023-11-05 Roleystone.png
Schermafbeelding 2023-11-05 100314.png
Re: Fire Weather - pwsFWI
Posted: Sun 10 Dec 2023 9:05 am
by HansR
@phil23 just notified me Australia is now in full swing of the fire season with an El Niño going on. It seems to be going a bit like 2019/20.
Below you find
his current pwsFWI status (click on the pwsFWI label in the header, screenshot).
You can follow the whole of Australia
here.
(Or check
here or
here).
Schermafbeelding 2023-12-10 095833.png
Re: Fire Weather - pwsFWI
Posted: Tue 16 Apr 2024 7:48 am
by HansR
@Anybody interested in Fireweather management: The webinar "
Fuel management for wildfire risk reduction and nature conservation", organised jointly by Firelogue and FoRISK from Forest Europe, is taking place on the 25th of April from 10:00 to 12:00 CEST.
You may register for free
here.
The webinar will feature presentations from four speakers, providing a broad territorial and sectoral perspective on the topic and aiming to gain insights into how we can synergistically address wildfire risk reduction and nature conservation challenges:
- Sebastian Kirppu from Protect the Forest in Sweden will commence with a case example from Northern Europe, illustrating how wildfire risk management and nature conservation can be interconnected.
- Antonio López from the Spanish Ministry for the Ecological Transition and the Demographic Challenge will delve into the topic of wildfires in Natura 2000 sites.
- Roman Berčák from the Czech University of Life Sciences Prague will discuss the challenges of multi-risk forest management in the context of nature conservation and wildfires, using the case of the Saxonian and Czech fires of 2022.
- Adrián Tišťan will offer a vision from DG Environment in the European Commission.
The webinar will be closed with a panel discussion among the speakers and the opportunity for questions by the public. The webinar will be moderated jointly by Alexander Held from the European Forest Institute and Julia Haas from Forest Europe.