Air Resources Laboratory partnered with the NOAA Office of Response and Restoration and the National Weather Service

June 20, 2024

The NOAA Air Resources Laboratory (ARL) partnered with the National Ocean Service Office of Response and Restoration (NOS OR&R) and the National Weather Service (NWS) to host a workshop based on the National Weather Service HYSPLIT tool for the NWS Weather Forecast Offices in the Central and Southern regions on Monday, June 17.

HYSPLIT is an atmospheric transport and dispersion model developed, updated, and maintained at ARL for about 75 years. It is used at NOAA and around the world for emergency response, planning, assessment and for estimating purposes. It directly supports NOAA’s strategic goal of providing science-based use-inspired decision support tools. The NWS Weather Forecast Offices use NWS-HYSPLIT to create simulations in response to a real event, in an exercise or to aid in planning. These are typically shared with emergency management officials. NWS-HYSPLIT has more features and capabilities than the publicly available version of HYSPLIT.

Click to enlarge animation
Demonstration of HYSPLIT trajectory animation
Click to enlarge animation

ARL Research Physical Scientist Mark Cohen, leader of the HYSPLIT modeling group, led the workshop with help from colleagues Sonny Zinn, principal developer of the NWS HYSPLIT system and HYSPLIT developers Alice Crawford and Chris Loughner. Sonny, Alice and Chris are subject matter experts who helped answer questions during the workshop. Additionally, Sonny did a lot of work ahead of the workshop updating and improving the NWS-HYSPLIT tool. 

Partners from the NWS who helped organize, support and contribute to this event included Alexandra Kelly and Chris McKinney, regional warning coordination meteorologists for the Central and Southern Regions, respectively, and Roham Abtahi of the Decision and Support Information Branch at NWS Headquarters. Dalina Swift-Viveros from the NOAA National Ocean Service’s Office of Response and Restoration also helped support the workshop. Dalina is the Chemistry Team Lead and the main developer of the CAMEO/ALOHA chemical modeling suite, parts of which are integrated into NWS-HYSPLIT.

Demonstration of HYSPLIT dispersion animation
Click to enlarge animation

There were about 75-80 participants in this virtual workshop who gained a better understanding of the types of events HYSPLIT is useful for, how to decide what type of HYSPLIT analysis to use, how it works and the sources and magnitudes of the uncertainties involved.

Chris McKinney, Regional Warning Coordination Meteorologist and Decision Support Services Program Manager for the NWS Southern Region Headquarters had this to say about the workshop:

“This training was a great opportunity for our meteorologists to gain a deeper understanding of one of our primary decision support tools for hazardous materials events. We are now better prepared to assist our partners when they face one of these low frequency, high impact events.”

Roham Abtahi, Surface Transportation Program Manager and HAZMAT Coordinator from the Decision Support Integration Branch at the National Weather Service Headquarters, wrote to express his thanks to Dr. Cohen and the rest of the team for the workshop. He said:

The presentation was a level of effort beyond the scope of anything I’ve witnessed in 20 years with the NWS, including nearly 200 slides, interspersed with time for questions from the field, and broken down by category to equip the NWS forecaster with in depth knowledge on a very complex topic.

ARL thanks the whole workshop team for all their hard work in pulling off such a successful training.