US and Canada Outlook
Northern US and Canada face cooler temperatures under La Niña, with increased snowfall potential in western Canada and northwestern US for December 27. Models predict negative snowfall anomalies overall but enhancements in higher elevations and northern plains.
Southern US expects above-normal temperatures, drier conditions, and below-average snow, per NOAA's DJF outlook. Storms may track northward, sparing the South but impacting Midwest travel.
La Niña's weak phase favors colder outbreaks in northwest US, with jet stream displacement bringing winter systems from polar regions.
Europe and Global Patterns
Europe's December 27 forecast shows below-normal snowfall across most areas, with high-pressure systems limiting widespread snow. Southeast regions may see slight increases into January.
Global La Niña effects include wetter Indonesia and drier central Pacific, influencing distant teleconnections. Negative AO/NAO phases could amplify cold air outbreaks in mid-latitudes.
Models like ECMWF confirm slower snowfall starts, with confidence in reduced continental snow cover early winter.
Asia Highlights: Hong Kong
Hong Kong anticipates dry, fine weather on December 27, cool mornings at 15°C min, max 21°C, under northeast monsoon. Low rain probability supports clear conditions.
Large day-night temperature swings inland, with northeast winds force 3-5. This aligns with broader southern China fine weather trends.
Sea temperatures at 21°C indicate stable coastal patterns amid La Niña's distant cooling.