Characterization of HRRR-Simulated Rotor Layer Wind Speeds and Clouds Along the Coast of California

Journal Article · Wed Nov 26 00:00:00 EST 2025 · Wind Energy Science

DOI:https://doi.org/10.5194/wes-10-2755-2025· OSTI ID:3014914

Lee, Jungmin ^[1]; Ghate, Virendra ^[2]; Mitra, Arka ^[2]; Miller, Lee ^[3]; Krishnamurthy, Raghavendra ^[3]; Egerer, Ulrike ^[4]

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1. Lawrence Livermore National Laboratory
2. Argonne National Laboratory
3. Pacific Northwest National Laboratory
4. National Laboratory of the Rockies, Golden, CO (United States)

Stratocumulus clouds, with their low cloud base and top, affect the atmospheric boundary layer wind and turbulence profile, thereby modulating wind energy resources. GOES satellite data reveal an abundance of stratocumulus clouds in the late spring and summer months off the coast of northern and central California, where there are active plans to deploy floating offshore wind farms at two lease areas (near Morro Bay and Humboldt). Since the fall of 2020, two buoys equipped with multiple instruments, including Doppler lidar, have been deployed for about 1 year in these wind farm lease areas to assess the rotor layer wind conditions in these locations. The objective of this study is to evaluate how well the High-Resolution Rapid Refresh (HRRR) model represents stratocumulus cloud characteristics and turbine-relevant rotor layer winds (surface to 300 m) by comparing HRRR simulations with buoy and satellite observations. We first find that the HRRR model reproduces the seasonal cycle of cloud top height reasonably well in these regions. However, during the warm season - especially at Morro Bay - the HRRR-simulated stratocumulus clouds tend to have lower tops by about 150 m and exhibit weaker diurnal cycles than satellite observations. Our analysis also shows that rotor layer wind speeds and vertical shear are stronger at Humboldt than at Morro Bay, and both are generally stronger under clear-sky conditions. Finally, the HRRR model bias in rotor layer wind speed is small under cloudy conditions but larger and dependent on observed wind speed under clear skies. Specifically, HRRR underestimates wind speeds at Morro Bay and overestimates them at Humboldt under clear-sky conditions.

• Research Organization: National Laboratory of the Rockies (NLR), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Wind Energy Technologies Office
• DOE Contract Number: AC36-08GO28308
• OSTI ID: 3014914
• Report Number(s): NLR/JA-5000-95558
• Journal Information: Wind Energy Science, Journal Name: Wind Energy Science Journal Issue: 11 Vol. 10
• Country of Publication: United States
• Language: English

Related Subjects

17 WIND ENERGY
California
clouds
HRRR
rotor-layer winds