The I-75 stretch from the GA border to Ocala had the dense smoke set up again in the pre-dawn hours this morning, and it dropped visibilities to less than a quarter mile at times. The temperatures from the surface up to about 5-600 feet cooled down fast last night under clear skies with light winds, but the temps above that layer stayed about 10-20 degrees warmer. Warm air on top of cold air sets up an inversion, and the smoke can’t break through it to rise. That essentially squeezes all the local brush fire smoke in the atmosphere down to the surface, making the visibility go way down. Once the sun comes up, the ground starts to warm and the smoke disperses, allowing the vis. to improve. Early morning travel may be tough again tomorrow morning.

Lake-effect snow is hammering on the shores of Lake Ontario this morning, but with an advancing warm front from the MW this will end shortly. An exiting storm has the wind cranking in the NE today, so I’m watching for some air travel delays from Boston to NYC.

The snow ahead of the front will give a 1-2” blanket on WI and MI today as well.

The Santa Ana winds are done for S CA but it will remain dry today, with the bulk of the valley rain and mountain snow edging through the Pacific NW into the Northern Rockies.

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