ARL-Managed Climate Reference Network Documents Record Rainfall from Hurricane Lane

September 2018

The two NOAA observing stations on the Big Island of Hawaii performed exactly as intended, bearing witness to the assailing rains of Hurricane Lane as it swept across the island in late August. According the U.S. Climate Reference Network, or USCRN, the official four-day rainfall total from August 22-25, 2018 was 47.59 inches; a sum large enough to classify as a 500-year rainfall event (one that has only a 1 in 500 chance of occurring in any given year).

The Hilo station, located on the “wet” side of the island, set a new 30-day rainfall record of 63.50 inches on August 27, surpassing its own network-high monthly record of 63.46 inches set in January/February 2008. The Mauna Loamountain station on the “dry” side of the island also witnessed record rainfall. Its previous record of 9.68 inches, set in December 2016, was quickly surpassed by the 11.98 inches measured during Hurricane Lane.

About the USCRN

The USCRN is a sophisticated, climate observing network that provides high-resolution data from its 138 operational sites in the conterminous U.S., Alaska, and Hawaii (Hilo and Mauna Loa are the only USCRN stations on Hawaii). Each site hosts a suite of instruments that monitor meteorological parameters. This instrumentation, which includes triple redundancy for primary variables such as precipitation, is calibrated annually to National Institute for Standards and Technology specifications by ARL’s staff of expert engineers. Resulting data are ingested by both the National Weather Service and National Centers for Environmental Information, where they are utilized for forecast and warning operations and archived as part of the long-term climate record; providing a baseline of high-quality data that can validate observations made by other networks and serve a diverse range of users across government, academia, and multiple industries.

NOAA’s vision for the USCRN is to provide a baseline of high-quality climate data that can be revisited in 50 to 100 years to effectively characterize climate change in the U.S. To that end, NOAA produces a yearly report documenting selected, climatologically significant, events such as Hurricane Lane. USCRN data are publicly available on-line in multiple formats, including quality controlled datasets and hourly observations.

For more information, please contact the USCRN Program Manager, Dr. Howard Diamond, at 301-427-2475 or

Satellite image of Hurricane Lane approaching Hawaii's Big Island
GOES-15 satellite image of Hurricane Lane positioned approx. 300 miles south of Hawaii's Big Island on August 22, 2018. Credit: NOAA Environmental Visualization Laboratory
Three pieces of monitoring equipment in a field
USCRN equipment at the University of Hawaii site in Hilo. Credit: NOAA Earth System Research Laboratory Global Monitoring Division