Hurricane Irma
Measured data for cyclone Irma, as finalised by the National Hurricane Center.
Official warnings come from the National Hurricane Center and your local emergency agency. This page is informational and does not replace an official advisory.
Wind
155 kt
Category 5
287 km/h · 178 mph
Pressure
914 hPa
Period
2017
Aug 30, 2017 → Sep 13, 2017 · 7 landfall
Position
| When | Position | kt | hPa | Category |
|---|---|---|---|---|
| Aug 30, 2017 00:00 UTC | 16.1, -26.9 | 30 | 1,008 | TD |
| Aug 31, 2017 00:00 UTC | 16.3, -31.7 | 55 | 999 | TS |
| Sep 01, 2017 00:00 UTC | 17.5, -35.1 | 100 | 967 | HU |
| Sep 02, 2017 00:00 UTC | 19.1, -39.7 | 100 | 967 | HU |
| Sep 03, 2017 00:00 UTC | 18.5, -45.5 | 95 | 973 | HU |
| Sep 04, 2017 06:00 UTC | 17.0, -51.5 | 105 | 952 | HU |
| Sep 05, 2017 06:00 UTC | 16.6, -56.4 | 135 | 933 | HU |
| Sep 06, 2017 06:00 UTC | 17.7, -61.9 | 155 | 914 | HU |
| Sep 07, 2017 06:00 UTC | 19.7, -67.6 | 145 | 920 | HU |
| Sep 08, 2017 06:00 UTC | 21.5, -73.2 | 135 | 925 | HU |
| Sep 09, 2017 12:00 UTC | 22.7, -79.3 | 110 | 941 | HU |
| Sep 10, 2017 12:00 UTC | 24.5, -81.5 | 115 | 931 | HU |
| Sep 11, 2017 12:00 UTC | 29.6, -82.7 | 50 | 970 | TS |
| Sep 12, 2017 12:00 UTC | 33.8, -86.9 | 20 | 1,000 | LO |
How to read this page
How to read wind and category
Irma had maximum sustained winds of 287 km/h, category Category 5 on the Saffir-Simpson scale — a 1-to-5 scale based on wind alone.
Where this data comes from
Track and intensity come from HURDAT2, the NOAA National Hurricane Center’s historical storm catalogue.
What the category doesn’t tell you
Irma’s category measures wind alone. Rain, storm size and storm surge aren’t in it, and have killed more people than wind in recent hurricanes.
Words on this page
Saffir-Simpson category
A 1-to-5 scale that classifies a hurricane by its maximum sustained wind. From category 3 up a hurricane counts as "major", with significant structural damage expected; the scale ignores rain, size and storm surge, which can be deadly even at a low category.
Standard definition by NHC — National Hurricane Center (Saffir-Simpson Hurricane Wind Scale) · Saffir-Simpson category
Preliminary data
A measurement published as soon as it is collected, before the agency’s final review. It can be corrected or withdrawn: earthquake magnitudes shift in the first hours, air-quality readings are revised weeks later. Use it to plan your day, not for regulatory or legal purposes.
- NOAA HURDAT2 (banco de melhores trajetórias)Licence: Domínio público (dado federal dos EUA) · Credit: NOAA / NHC, HURDAT2 (Atlântico e Pacífico Nordeste)
How to read these numbers
Track points come from HURDAT2, with position, wind and pressure every six hours. Rows marked as landfall are the moments when the centre crossed the coastline.
Frequently asked questions
- What category did Irma reach?
- The sheet shows the peak category, derived from the highest one minute sustained wind in the final reanalysis.
- Why is the death toll not shown?
- Deaths and damage come from narrative reports with varying methodology, not from the track database. We leave that number to the official source.