Temperatures across much of the US will be milder than average for the remaining days of winter and into the start of spring. Above-average temperatures are forecasted across most of the Lower 48 states from January through March. Temperatures will likely be the most above average from eastern Utah through the southeast.
Those areas near the West Coast may experience temperatures near average or slightly warmer. However, it is important to point out that each month could have temperature fluctuations that differ from the overall trend.
The La Niña, the cooling of sea-surface temperatures in the equatorial Pacific Ocean, appears to have peaked and will likely influence weather conditions across the globe this winter. La Niña events are typically associated with warmer-than-average conditions for parts of the U.S. in January and February.
The recent upper-level pattern isn’t what is typically expected in a La Niña winter. Specifically, ridging has developed in the North Atlantic, which indicates the North Atlantic Oscillation (NAO) has trended negative – favorable for atmospheric blocking.
Strong blocking, particularly in the North Atlantic, can override La Niña. “Given the tendency towards more North Atlantic ridging than expected in December and supported by new climate model solutions, which are a little less extreme with the eastern U.S. warmth, we’ve shifted the focus of the most anomalous warmth to the central/western U.S.,” explained Todd Crawford, chief meteorologist at The Weather Company.
When North Atlantic blocking is more frequent in a La Niña winter, the warmest temperatures compared to average tend to be across the West. A more typical La Niña pattern may return in January and February, but the recent pattern has resulted in more uncertainty in the North Atlantic pattern this winter, which could lead to additional forecast changes.
Much-above-average temperatures will stretch into eastern Utah. However, January is the coldest time of year for much of the U.S., so it is important to keep in mind that an above-average forecast still suggests it will be cold at times. Temperatures may be closer to average along the West Coast and across much of the northern tier.
Conditions are expected to trend warmer than average in February for most of the Lower 48. Temperatures will be far above average for a large area of the U.S., reaching into the West as we’re seeing that closer to the West Coast and across portions of the northern tier, temperatures are trending close to or either side of average.
March will likely continue the warmer-than-average trend of the first two months of the year. In the West, temperatures will be the most above average into Utah, while warmer-than-average temperatures will extend into Nevada and Southern California. The Pacific Northwest can expect temperatures to be near-average or slightly warmer.