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AgWeatherNet (AWN) Update

Written by Nathan Santo Domingo, Field Meteorologist, 5/2/2024


Worker Heat Awareness

It’s that time of year where heat safety becomes top of mind. Last year, the Tri-Cities hit 90°F for the first time on May 3rd. On average, May 21st is the first 90 degree day in the Tri-Cities followed by Yakima on the 31st. While the extreme heat typically waits until late June or July to arrive, it’s important to keep heat safety in mind even early in the season. So far, this spring has been relatively cool, so a quick warmup into the 90s could come as quite a shock to our bodies.

With that in mind, this month, AWN is featuring our Worker Heat Awareness tool. Developed in collaboration with the Pacific Northwest Agricultural Safety & Health (PNASH) Center, its goal is to deliver timely information to workplace supervisors about actions that can be taken to reduce the risk of heat illness in workers. This product provides heat guidance that is aligned with the Washington State Outdoor Heat Exposure rule (WAC 296-307-097) for agricultural workers.

This tool utilizes either the National Weather Service National Digital Forecast Database (NDFD) data, or the in-house AWN forecast model if a station has a sufficient period of record. It is designed for users to be able to take a quick glance at their station of choice so they can be aware which day (or days) may feature the greatest risk of heat illness.

Here’s an example of what a recent graph from Pullman looks like, indicating no risk of heat illness for early May 2024.

air temperature forecast graph for Pullman

In a more extreme example, here’s what the graph looked like from June 25 through July 2, 2021, during a historic heat wave.

air temperature graph for Richland, June-July 2021

After signing in to your free AWN account on our website, under the “Models” tab in the menu, click the down arrow next to “Human” and select Worker Heat Awareness to access this tool.

Weather With AWN

Episode 4 of Weather with AWN will be at 3:30 p.m. on Thursday, May 30th. AWN staff will be discussing some of the weather-guided irrigation management tools on the AWN web portal. Also joining the call will be Professor and Extension Irrigation Specialist R. Troy Peters, PhD, who will provide additional input and help answer user questions.

You can join the Zoom meeting by visiting the new Events page on the AWN website.

Spring Frost Program Reminder

We are nearing the end of the 2024 Spring Frost Program for the Yakima Valley, Central Basin, Wenatchee, and Okanogan growing districts. User frost reports can be submitted by clicking the Spring Frost Program tab on the AWN website menu. Daily forecasts will continue until the end of May.


Nathan Domingo
Nathan Santo Domingo
Field Meteorologist, AgWeatherNet

Funding and Acknowledgements

The AgWeatherNet Spring Frost Program is supported in part by Washington State Tree Fruit Association and a grant from WSDA SCBG Program (2021-2024).

AgWeatherNet air quality sensing and reporting is supported in part by the Washington State Department of Labor and Industries.

Connect With AWN


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