Call it fortuitous timing. Hours before U.S. President Donald Trump issued a tweet last week panning climate change, a University of Georgia climatologist offered a lengthy pre-emptive explanation.

"What we are seeing right now in the United States is just … well … wait for it … winter," wrote Marshall Shepherd, director of the atmospheric science program at the University of Georgia and a former president of the American Meteorological Society.

Shepherd wrote that he would urge people to keep in mind that "weather is mood, climate is personality" and that weekly weather patterns say little about longer-term climate change.

It came about 12 hours before Trump tweeted that forecasts were calling for record cold New Year’s Eve temperatures.

>> See the tweet here

Shepherd wrote that even as climate warms, the seasons will always change to winter and yield frigid weather, snowstorms and blizzards. After all, he said, winter is related to how the Earth is tilted on its axis as it revolves around the sun.

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Concludes Shepherd: "For now, the message for this week and the next seven days is that winter is reminding us that it still exists and always will even as our climate warms. Prepare accordingly, stay warm and help others."