NWS Seattle Briefings & Information

Hawaii and Guam Concerns; Record Warmth Spreads Eastward; Heavy Snow for Sierra-Nevada; Severe Weather for Plains

A very active spring pattern with tropical concerns across the Pacific. Heavy rainfall will continue to impact Hawaii this weekend. Meanwhile we continue to monitor a developing typhoon that may affect Guam into early next week. For the Lower 48, heavy snow for mountains of California this weekend, increase threat for severe thunderstorms next week for the Plains and record warmth spreads east. Read More >

Weather Risk Outlook

The Weather Risk Outlook colors are determined after NWS Seattle meteorologists examine both the impact level of potential weather scenarios AND the associated probability of those scenarios. The resulting outlook displays the highest risk for each day.

NWS Seattle meteorologists first use the impact table to determine the level of impact expected with a forecast weather event.

NWS Seattle meteorologists then determine the color by determining the probability of occurrence using all the available information and then reference the matrix to determine the risk level associated with the forecast weather event.