Thursday is a FIRST ALERT WEATHER DAY and here’s why

Thursday is a FIRST ALERT WEATHER DAY and here’s why
(Source: WMC Action News 5)

MEMPHIS, TN (WMC) - Cold Canadian air has a chilly grip on the Mid-South and more cold air is on the way.

As this cold air is in place a developing low pressure system will move out of Texas Wednesday drawing an abundance of Gulf moisture into the Mid-South.

This will trigger rainfall on Wednesday and that precipitation is expected to continue into Wednesday night as temperatures fall into the lower thirties.

Current forecast models indicate enough moisture in place for precipitation and temperatures cold enough to form snow, but questions still remain as to the whether the cold air and moisture will combine at the right time to produce snow here in the Mid-South.

The biggest uncertainty at this time is the exact track of the low pressure system.

Air travels in a counterclockwise fashion around a low pressure system which creates a major factor in determining what type of precipitation will fall.

Because the low is tracking northeast out of Texas it will be drawing up warm air from the Gulf Coast in advance of it.

(Source: WMC Action News 5)

As the low lifts north it will draw in cold air to mix in with the warm moist layer. The better chance of rain changing to snow will be on the backside of the low pressure system.

Then comes the question of how much moisture will be available to wrap around the backside of the low and how fast will the low be moving as it treks through the Mid-South.

As of Monday there was still a wide range of solutions among the forecast models with one model showing all rain, another showing just a quick change of rain to snow after midnight Wednesday night, and another showing rain changing to snow Wednesday evening and continuing well into Thursday morning.

The exact time of change over and the number of hours of snow will of course impact the potential and amount of accumulation.

At this time there remains uncertainty but the First Alert Weather Team wants you to be prepared in the event of snow developing Wednesday night and the potential to have the Thursday morning commute disrupted.

We’ll continue to track this developing situation and keep you updated on the air, on the web, and on the First Alert Weather app. So stay tuned for more information leading up to the event.

Ron Childers

Chief Meteorologist

WMC Action News 5

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