Winter Mischief Friday 

Posted: 5:46 pm Thursday, December 7th, 2017

By Kirk Mellish

As always some of the details, like start and stop times are hard to pin down across a metro area larger than some of our states. But the main saving grace is no freezing rain is expected so no ice storm worries. Also, air temperatures are expected to stay above freezing for most of “the event”.

DO NOT EXPECT TO WAKE UP TO A BLANKET OF WHITE TOMORROW. It starts as rain or a rain/sleet/snow mix.

Temperatures may drop below freezing after 8pm or so Friday but maybe not until after midnight for many. But this could change so stay tuned.

The mix of rain, sleet and snow will vary and be light at times or even stop at times, with little or no accumulation expected for many of our far South and East suburban counties nor for the NW corner of the state. SW metro and NE mountains may be the sweet spots.

What is more, the “rain/snow” line will vacillate across the region during he course of the day and evening, it will not be static, so conditions will be changeable regarding where the snow or rain is at any given time so it wont be uniform. That R/S line aloft is in constant motion wiggling over the metro area so there’s no way to give a definitive location or time frame for “the worst”.

As always there are models showing mostly rain, or mostly snow and they disagree on amounts and locations and timing of start and stop.

Drizzle tonight will transition to scattered showers then more widespread light rain overnight with some pockets of snow mixing in before sunrise give or take a few hours. Areas toward AL will transition toward snow first.

I don’t have any major disagreement with where the Atlanta National Weather Service has issued the WINTER WEATHER ADVISORY (purple) for Friday, although I could quibble:

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The farther south and east of downtown you are the LESS likely you see any real snow accumulation. Areas West of I-85 have the best odds of a coating to an inch or so snow accumulation, mainly on objects above ground like trees, bushes, car tops, decks and grassy areas. But always beware bridges just in case.

NOAA/WPC PROBABILITY OF AT LEAST ONE INCH OF SNOW:

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NOAA/WPC “LOW” RISK AREA FOR UP TO 4 INCHES:

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WPC TOTAL SYSTEM ACCUMULATION FRIDAY-FRIDAY NIGHT (give or take half an inch):

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So for most of the region ONLY a dusting to half an inch or so, but some lucky spot could get 1-2 but no way to know where that might be. But again, mainly grassy areas not roads either way. NO loss of power is anticipated due to the weather in Atlanta.

Thanks to marginal temperatures this will not be like any of the recent snow jams or ice jams where air temps were in the mid to upper 20s, instead we start near 40 then fall to the low to mid 30s.

Obviously things can change so check back for updates and our team traffic reports live on the radio all day Friday and Friday night.

Follow me on Twitter @MellishMeterWSB.

 

 

 

 

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