re: Wintry Precip Possibility Friday Night, LA

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Just some rain... and cold... no icy or snowy weather...

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Possible icy road conditions from up to West feliciana down to EBR. Roads will still be wet when temps get under 32. No snow though.

1134 AM CST THU JAN 5 2017

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
LOUISIANA...SOUTH MISSISSIPPI AND THE ADJACENT COASTAL WATERS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

A STRONG COLD FRONT WILL BRING MUCH COLDER AIR TO THE AREA FRIDAY
THROUGH SUNDAY. THERE IS A POSSIBILITY OF A WINTRY MIX OF
SLEET...SNOW FLURRIES AND A COLD RAIN MAINLY NEAR AND NORTH OF THE
LOUISIANA - MISSISSIPPI STATE LINE LATE FRIDAY AFTERNOON AND
FRIDAY NIGHT THAT MAY PRODUCE HAZARDOUS TRAVEL CONDITIONS. FREEZE
AND HARD FREEZE WARNINGS WILL LIKELY BE NECESSARY FOR MUCH OR ALL
OF THE AREA SATURDAY NIGHT. WIND ADVISORIES MAY BE NECESSARY SOUTH
OF LAKE PONTCHARTRAIN IN THE NEW ORLEANS METRO AREA.

THIS WILL ALSO BRING VERY HAZARDOUS CONDITIONS FOR MARINE
INTERESTS FRIDAY THROUGH SUNDAY. SMALL CRAFT ADVISORIES WILL BE
NECESSARY...AND GALE WATCHES OR WARNINGS MAY BE NEEDED.

THE THREAT OF HAZARDOUS WEATHER FOR MONDAY THROUGH WEDNESDAY IS
LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT ANTICIPATED.

NAM model:

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difficult to predict the severity of winter weather in the south.

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you see that pink sliver in Louisiana? that's driving on ice.

if that pink sliver "moves" 2 inches east northeast, no ice in Louisiana.

that sliver is defined by temperature.

is it going to be 29 or 31 there, or 33?
that's the whole thing.
29 snow
33 sleet and rain
somewhere in-between ice.

Freezing temps chasing the precipitation. That's not an ice scenario for South La.

Looks like central Mississippi into Alabama and Georgia will actually catch it. Prayers sent for folks flying out of Atlanta this weekend.

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is it going to be 29 or 31 there, or 33?
that's the whole thing.
29 snow
33 sleet and rain
somewhere in-between ice.

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No. No, that is not how it works. It can be 29, or colder, and sleeting or even raining (freezing rain). It depends what temperature the column is all the way up. According to this, the temperature may be slightly above freezing around 850mb which would mean sleet or freezing rain if the surface is at or below freezing. On the other hand, it can be above freezing and snowing because the above freezing column of air is very shallow and only at the surface so the snow does not have time to melt before getting to the surface.

I wouldn't mind a repeat of the '08 snow, but ain't gonna happen.

Winter weather advisory expanded south to include parts of the northshore.

Well that settles it







Hammond is officially northshore

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I have seen snow when it was 40 degrees and rain at 29 degrees. you never know.

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The weather can get crazy in lots of places not named San Diego of Hawaii, but Louisiana has particularly crazy weather. Snowing at 40 will not cause significant problems though, because there will be no accumulation. Significant rain at 29 degrees will freeze on the ground and trees, causing significant problems in the South. So there's all of that.

Speaking of crazy weather, when I was in Kosovo, once the weather got cold, it rarely got above freezing the rest of the winter. It would warm up to snow.

True story.