January’s atmospheric conditions led to variations in solar conditions across North America. High pressure anomalies over the West Coast and Rockies brought solar gains but also increased wildfire risks. The Midwest also saw above-average irradiance, while Canada and the Gulf Coast saw declines due to increased cloud cover. According to analysis using the Solcast API, ISO New England and PJM outperformed long-term trends in capacity-adjusted performance, whereas ERCOT performed only slightly above average.
The West Coast and Rocky Mountains saw irradiance levels up to 20% above the January average. A dominant high-pressure system over the North Pacific played a key role, keeping storm systems offshore and directing dry, northerly winds over much of the western United
States. This pattern led to reduced cloud cover and suppressed rainfall, significantly boosting solar potential. However, these same conditions also contributed to severe and destructive wildfires in California.
In the Midwest, irradiance levels were well above average, with areas south of the Great Lakes seeing values up to 30% higher than a typical January. This increase was driven by a cold but relatively dry northerly air mass that moved over the region. As a result, skies cleared more quickly than usual following snowfalls, allowing for more sunlight to reach the ground.
This solar surge led to increased production for US grids with ISO New England achieving 28.9% while PJM seeing a 21.6% rise, both compared to January average values from 2007-2024. While January is typically a low-irradiance month, colder temperatures helped to boost the efficiency of solar panels, partially mitigating the seasonal dip in solar generation.
Further south, the Gulf Coast experienced near-average to below-average irradiance, with the western portion of the region particularly affected. This was due to increased convective cloud cover which reduced solar potential. As a result, ERCOT saw only a marginal irradiance benefit of 1.43% above average, as its weather patterns remained relatively stable compared to the dramatic shifts further north.
Meanwhile, much of Canada saw below-normal irradiance, which is already low during this time of year due to the sun’s low position on the horizon. The combination of increased cloudiness and limited daylight hours resulted in one of the least favorable regions for solar generation in January.
Solcast produces these figures by tracking clouds and aerosols at 1-2km resolution globally, using satellite data and proprietary AI/ML algorithms. This data is used to drive irradiance models, enabling Solcast to calculate irradiance at high resolution, with typical bias of less than 2%, and also cloud-tracking forecasts. This data is used by more than 300 companies managing over 150GW of solar assets globally.
The views and opinions expressed in this article are the author’s own, and do not necessarily reflect those held by pv magazine.
This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: editors@pv-magazine.com.
By submitting this form you agree to pv magazine using your data for the purposes of publishing your comment.
Your personal data will only be disclosed or otherwise transmitted to third parties for the purposes of spam filtering or if this is necessary for technical maintenance of the website. Any other transfer to third parties will not take place unless this is justified on the basis of applicable data protection regulations or if pv magazine is legally obliged to do so.
You may revoke this consent at any time with effect for the future, in which case your personal data will be deleted immediately. Otherwise, your data will be deleted if pv magazine has processed your request or the purpose of data storage is fulfilled.
Further information on data privacy can be found in our Data Protection Policy.