National Tree Dispatch
How we source our wind data
This site connects homeowners with tree crews and arborists for fallen, leaning, and storm-damaged trees, and publishes the recent wind readings we hold for each postcode as context after a storm.
Whether a tree fails depends far more on the tree than on the weather. Species, age, internal decay, root damage, previous pruning, and exposure all matter, and none of them are visible in a wind reading. The weather is simply the part we can measure and publish.
Where each number comes from
Weather readings
Open-Meteo forecast API, which aggregates output from national weather service models. For each postcode we store the highest recent daily precipitation total, precipitation hours, a multi-day precipitation sum, and the strongest daily wind gust for that postcode's coordinates. Precipitation is liquid-equivalent rain/hail total — not hailstone diameter. We do not operate weather stations and we do not measure anything at your property.
Official nearby reports and alerts
United States: NOAA Storm Prediction Center local storm reports (hail size in inches, wind/damage reports) for today and yesterday. Australia: Bureau of Meteorology land-warning RSS for live severe thunderstorm / severe weather / flood-style warnings, matched to postcodes by forecast district (town anchors within ~75 km — never a whole-state blast), plus the Severe Storms Archive event catalogue which can lag real time. Canada: Environment and Climate Change Canada weather alerts and thunderstorm outlooks via GeoMet, matched when a polygon covers the postcode. These sources are named only to describe origin; none of them endorse this site.
Housing density
Published national census sources — the US Census Bureau, the Australian Bureau of Statistics, and Statistics Canada — expressed as dwellings per square mile or square kilometre for the surrounding area.
Typical build year
Published census construction-year data, shown only where the source actually holds it. The Australian census does not collect dwelling construction year, so Australian pages omit the figure entirely rather than estimate it.
Severe readings counter
A running count of how many times a postcode's readings have crossed our severe threshold since we began monitoring it. It starts from zero at that point and is not a historical storm record.
How the sector status is calculated
The status on each postcode panel is a plain threshold we apply ourselves so the page can be read at a glance. It is our own rule of thumb — not an industry standard, not a hazard rating, and not an insurance classification. The exact rules are:
Thresholds are expressed in inches and miles per hour because that is how we store readings; pages in Australia and Canada convert them to millimetres and kilometres per hour for display.
How current the readings are
Postcodes are refreshed on a rotating queue rather than continuously, so this is not a live feed. Every postcode page shows the timestamp of its own most recent collection, and that timestamp is the only freshness claim we make. If a page has never been collected it says so instead of showing a substitute date.
Because the queue rotates, a very recent or very localised storm may not appear in the readings yet.
What this data is not
- —It is not a tree risk assessment. That is a site visit by a qualified arborist who examines the tree, its defects, and what it could hit.
- —It is not specific to your garden. Gusts vary sharply with shelter, terrain, and surrounding buildings.
- —It cannot see decay. Trees with advanced internal decay fail in ordinary wind, so a baseline reading is not reassurance about any particular tree.
- —It is not a safety clearance, and it never authorises anyone to approach a damaged tree or a tree near power lines.
Independence and affiliation
We are not affiliated with, endorsed by, accredited by, or certified by any weather agency, census authority, standards body, trade association, or insurer. Where we name a data source, we name it only to describe where a number came from. Threshold anchors such as NWS severe criteria are reference points for our own labels — not a claim that NWS, BOM, or ECCC reviewed this site.
Contractors who receive requests are independent businesses. In the field they typically work to the trade practices normal for their discipline — for example HAAG-style roof documentation, ISA TRAQ tree risk assessment, or IICRC S500 water restoration. Those frameworks describe contractor work; they do not define the weather thresholds published here.
We are not a contractor and carry out no field work. Assessment, pricing, and any work performed are matters between the contractor and the homeowner.
Corrections
If a reading, city name, or postcode on this site looks wrong, we want to know. Contact details and the process for data requests are on our terms and privacy page. Corrections to underlying weather or census data have to be raised with the original source, but anything we have mapped incorrectly we can fix.