Sunday, June 1 – PHOENIX, Arizona – A rare early-June weather pattern is taking shape across Arizona, as a storm system coupled with tropical moisture from the south is forecast to bring widespread rainfall, gusty winds, and the risk of small hail across the state.
Rain, thunder and cooler temperatures kick off the week
From Sunday into Monday, the incoming disturbance will interact with moisture streaming northward, increasing the potential for scattered thunderstorms especially in southern and central Arizona. The best chances for stronger storms will occur in the high country through midweek, where localized downpours may lead to flooding concerns.
A Flood Watch is active for Sunday across southern Arizona, notably south of Casa Grande, impacting cities like Tucson, Ajo, and Sierra Vista. Rainfall totals in lower desert regions could reach 0.25 to 0.5 inches (6 to 13 mm), while mountain areas may see 0.5 to 0.75 inches (13 to 19 mm), with localized higher amounts where thunderstorms intensify.
Unusual weather history and temperature shift
This weather anomaly aligns with a historic rarity: Phoenix has only recorded rain once on June 1st in over a century—0.02 inches in 1914. The current setup is breaking climatological norms not just in precipitation, but in temperature patterns as well.
Typical highs for early June in Phoenix are around 100°F (38°C), but today and into Monday, temperatures will linger in the upper 80s to low 90s (31–34°C). By Thursday, the heat is expected to return, with highs climbing back into the triple digits.
Storm highlights
This early-summer weather twist brings:
- Rain chances statewide, peaking Sunday through Monday
- Potential for strong storms with hail and strong wind gusts
- Flood Watch in effect for parts of southern Arizona
- Cooler-than-normal temperatures, rare for early June
Residents across Arizona should expect volatile skies, especially in elevated terrain and southern counties, as this tropical-infused storm system marks an unusual start to the month of June.


