Shahryar Fazli, Wenzhao Li, Rejoice Thomas, Surendra Maharjan, Mohammad Sina Jahangir, André Daccache, Hesham Morgan, Mohamed Allali, Hesham El‐Askary
As climate change intensifies, extreme weather increasingly threatens California’s Central Valley (CV), a vital agricultural region exposed to rising risks from heatwaves (HW), droughts (DR), and compound extremes. These events disrupt crop productivity and broader processes like water demand, pest dynamics, and soil stability, posing systemic risks. This study examines the spatiotemporal dynamics of HW, coldwaves (CW), DR, excessive rainfall (ER), and their compound (e.g., HWDR) and cascading forms from 1951 to 2025, using NOAA nClimGrid-Daily data. We assessed trends in frequency, intensity, and duration over long-term (1951–2025) and mid-term (1981–2025) periods. Results show increasing HW and DR in the southern CV, with 35 % and 60 % of the region exhibiting strong upward trends in HW frequency and intensity (mid-term), respectively, linked to warming (+0.234 °C/decade) and precipitation variability. Northern CV, especially Tehama to Sacramento, shows greater vulnerability to ER, CWDR, and CWER, reflecting heightened climate variability. Hotspots of extremes are shifting northward, with HWDR migrating at 20.94 km/decade. June–July HW and DR peaks coincide with critical crop stages, while February–March rainfall supports early vegetation growth. Almonds showed the highest vulnerability to drought, with severe kNDVI anomaly drops in 2014, while grapes responded moderately to heat and benefited from early rain, reaching a kNDVI anomaly peak of 0.03 in 2005. Intra-annual analysis reveals that 2014′s extreme HW and DR, combined with low rainfall and groundwater decline, intensified stress during hull split and fruit set. Targeted strategies like precision irrigation and drought-tolerant cultivars are essential to enhance agricultural resilience.