Overall Green alert Tropical Cyclone for HERNAN-20
in Mexico,

Event summary

Tropical Cyclone HERNAN-20 can have a low humanitarian impact based on the maximum sustained wind speed, exposed population and vulnerability.

GDACS ID TC 1000703
Name HERNAN-20
From - To 26 Aug - 28 Aug
Exposed countries Mexico,
Exposed population No people in Category 1 or higher
Maximum wind speed 74 km/h Tropical storm
Maximum storm surge 0.2 m (28 Aug 07:00 UTC)
Vulnerability Medium (Mexico)

GDACS Score

For more info on GDACS alert score click here.
Wind Storm surge Rainfall GDACS score
GDACS NOAA 46 km/h 0.2 m n.a. 0.5
Single TC: maximum expected impact (wind, storm surge, rainfall)
HWRF n.a n.a. n.a. n.a.
GFS 79 km/h 0 m 561 mm 0.5
ECMWF 90 km/h 0.2 m 680 mm 0.5
Maximum expected impact (wind, storm surge and rainfall) using different data sources.
Virtual OSOCC
Meteo assessment
Satellite products
Analytical products
Mexico - Tropical Storm HERNAN (ECHO 27 Aug 2020)Thu, 27 Aug 2020 13:02

  • Tropical Storm HERNAN formed in the Eastern Pacific on 26 August and is moving north, along the Mexican western coast. On 27 August at 3.00 UTC its centre was approximately 170 km south-west of Manzanillo (Colima State, central-western Mexico), with maximum sustained winds of 65 km/h.
  • Heavy rain has been reported in Colima and neighbouring Guerrero State, where one person is missing and several municipalities were affected by flooding and landslides.
  • On 27-28 August, HERNAN is forecast to move north, parallel to the coasts of Jalisco and Nayar States, with maximum sustained winds up to 65 km/h. It is expected to downgrade to a tropical depression as it moves towards the south of Baja California Peninsula.
  • Over the next 24 hours, heavy rain, strong winds and thunderstorms are forecast over Jalisco, Nayar Colima, Michoacán and Chiapa States.
Mexico - Tropical Storm HERNAN update (ECHO 28 Aug 2020)Fri, 28 Aug 2020 13:05

  • Tropical Storm HERNAN continues moving north, along the Mexican western coast, and on 28 August at 3.00 UTC, its centre was located approx. 180 km west of Puerto Vallarata (Jalisco State, central-western Mexico),  with maximum sustained winds of 65 km/h.
  • Heavy rainfall and river overflow were reported on 27 August in coastal Colima State. According to national authorities, two people were injured, and at least 100 individuals were displaced in Armeria, and Manzarillo Municipalities. A number of houses and roads were damaged by flooding waters.
  • HERNAN is forecast to move north-west, towards the southern tip of the Baja California Peninsula, as it downgrades to a tropical depression in the early morning of 29 August.
  • On 28-29 August, very heavy rainfall, strong winds and thunderstorms are forecast in Nayarit and Jalisco States, while heavy rainfall is expected over Baja California Sur, Sinaloa, Colima, Michoacán, Guerrero, Oaxaca and Chiapas States.
Detailed event map. European Union, 2024. Map produced by EC-JRC.
The boundaries and the names shown on this map do not imply official endorsement or acceptance by the European Union.

Updates on volcanic activity (Smithsonian)

Latest media headlines

Articles: 97 | About casualties: 2 | Last hour: 0

Hurricane tracker: The 14 churning systems tearing devastating paths r ... Tue, 01 Sep 2020 04:26:00 +0200.

Hurricane Laura has developed into an “extremely dangerous Category Four hurricane” according to the 's National Hurricane Center. As of 7am CDT (1pm BST) the Laura was located at latitude 31.2 north, longitude 93.3 west which is 20 miles n
...(more)
NASA Terra Satellite examines Tropical Storm Hernan’s relocated centerSat, 29 Aug 2020 08:59:00 +0200.

NASA infrared imagery revealed a burst of strength in Tropical Storm Hernan, located over the Gulf of California. At 12:30 a.m. EDT, NOAA’s National Hurricane Center or NHC noted that recent satellite-based wind data indicated Hernan was lo
...(more)
NASA Terra Satellite examines Tropical Storm Hernan's relocated centerSat, 29 Aug 2020 04:48:00 +0200.

NASA infrared imagery revealed a burst of strength in Tropical Storm Hernan, located over the Gulf of California. At 12:30 a.m. EDT, NOAA's National Hurricane Center or NHC noted that recent satellite-based wind data indicated Hernan was lo
...(more)
NASA Terra Satellite examines Tropical Storm Hernan's relocated centerFri, 28 Aug 2020 22:37:00 +0200.

Credit: NASA/NRL. NASA infrared imagery revealed a burst of strength in Tropical Storm Hernan, located over the Gulf of California. At 12:30 a.m. EDT, NOAA's National Hurricane Center or NHC noted that recent satellite-based wind data indic
...(more)

View more news

Estimated casualties (PAGER)

USGS estimates the number of casualties for each earthquake for the Prompt Assessment of Global Earthquakes for Response (PAGER) product.
The graph shows the current fatalities estimate.

Exposed population

Data, images, links, services and documents

For this events, GDACS has links to information from the following sources: EC-JRC (38), (2), DesInventar (1), WMO (1), INFORM (2),