What are the possible weather extremes for Bloomsday?

The all time high for early May of 92 degrees (set on 5/5/92 ) suggests Bloomsday could be quite warm. Moderate to heavy rain on the preceding days could combine with warm temperatures to produce an unusual hot and muggy day.

The strongest wind recorded at Spokane International in May is 53 mph. Running against a strong breeze is not ideal. Steady winds and temperatures in the upper 20s or lower 30s would likely result in some discomfort among the tens of thousands out in the elements on Bloomsday.

The worst wind scenario would likely be dry conditions for the months and week preceding Bloomsday and steady southwest breezes of 30 plus mph combining for reduced visibilities and high levels of airborne particulates with blowing dust. Heavy rain is unlikely, but not impossible. Rainfall rates up to 1 inch per hour have occurred in the spring in Spokane . These conditions likely coupled with temperatures in the 30s and 40s would not be welcome in Spokane on the first Sunday in May.

Spring showers are common in Spokane during the first week of May. Many of the past Bloomsdays had light and intermittent showers. This type of activity is more likely in the afternoon, but can occur in the morning. Taking this type of weather to the extreme introduces hazards such as lightning, strong winds, hail and tornadoes. The small soft hail that occurs frequently in the spring has visited Bloomsday from time to time. Thunderstorms have also occurred on the first Sunday in May in Spokane . The occurrence of strong thunderstorm winds, large hail and tornadoes is very rare in Spokane , but cannot be completely ruled out during the more favored months of May and June.

Snowfall in May in Spokane is unusual, but not unheard of. Two of the past Bloomsdays (1984 and 2002) have had some snow or hail falling from the sky. The records at Spokane International show an extreme 3.5 inches of snow on May 11, 1967 . But the worst Bloomsday weather scenario nearly came to pass in May 2002. On Tuesday May 7, 2002 (two days after the race) about 20 miles west of the course, up to 19 inches of snow fell in a very unusual late season storm. This was not a high elevation mountain storm; it occurred across the 2500 foot elevation west plains areas of Davenport , Rearden and Airway Heights . This storm brought only ½ inch of snow to Spokane International and just a few flakes to the downtown area. Needless to say an event like this over the downtown area on the first Sunday in May would put a real damper on Bloomsday.