Birmingham’s new discussion discusses the fun and games for tonight
Forecast Discussion
National Weather Service Birmingham AL
454 PM CST Fri Dec 8 2017
.SHORT TERM...
This evening and overnight.
--Hazardous travel conditions in the coming hours; periods of
accumulating snow to continue across a chunk of Central Alabama
into tonight as rain/snow transition line moves farther into
Southeast Alabama--
--Winter Storm Warnings extended in duration and area; Winter
Weather Advisories expanded in duration and area--
As of 22:45Z/4:45PM, a long fetch of precipitation was moving
northeastward along a H850 thermal gradient aligned atop the
Southeastern U.S. KBMX and KMXX DOPPLER radars show a defined
mixing line on CC, located just north of the I-85 corridor. A
wintry mix is occurring along the transitional CC axis, with rain
south and snow north. [thanks to the ground truth confirmation
from those sending p-type reports via mPING and social media.]
The mixing line is forecast to eventually move farther southeast
given additional low-level cold advection tonight. Overrunning
will continue to support waves of precipitation across Central and
Southern Alabama, with a focus generally near and southeast of
I-20.
Additional snowfall accumulation is expected tonight as a few
more spokes of lift move through the forward flank of the upper-
level trough; thus, the Winter Storm Warnings and Winter Weather
Advisories have been expanded in time and area. Forecast models
continue to indicate that our far southeastern counties (which
have been all rain so far) will begin to acquire thermal profile
supportive of a wintry mix and then snow overnight just in time
for the concluding/back side of the precipitation shield.
Surface temperatures are expected to fall well below freezing
for most of the region tonight, and nighttime lows have been
significantly lowered. Freezing of slush and meltwater on roadways
is certain; thus, travelers should be alert for hazardous travel
conditions tonight into Saturday morning. Additionally, trees,
tree limbs and power lines may go down due to the weight of snow.
Many County Emergency Managers and local police have urged
citizens to travel only if necessary overnight.
Forecast Discussion
National Weather Service Birmingham AL
454 PM CST Fri Dec 8 2017
.SHORT TERM...
This evening and overnight.
--Hazardous travel conditions in the coming hours; periods of
accumulating snow to continue across a chunk of Central Alabama
into tonight as rain/snow transition line moves farther into
Southeast Alabama--
--Winter Storm Warnings extended in duration and area; Winter
Weather Advisories expanded in duration and area--
As of 22:45Z/4:45PM, a long fetch of precipitation was moving
northeastward along a H850 thermal gradient aligned atop the
Southeastern U.S. KBMX and KMXX DOPPLER radars show a defined
mixing line on CC, located just north of the I-85 corridor. A
wintry mix is occurring along the transitional CC axis, with rain
south and snow north. [thanks to the ground truth confirmation
from those sending p-type reports via mPING and social media.]
The mixing line is forecast to eventually move farther southeast
given additional low-level cold advection tonight. Overrunning
will continue to support waves of precipitation across Central and
Southern Alabama, with a focus generally near and southeast of
I-20.
Additional snowfall accumulation is expected tonight as a few
more spokes of lift move through the forward flank of the upper-
level trough; thus, the Winter Storm Warnings and Winter Weather
Advisories have been expanded in time and area. Forecast models
continue to indicate that our far southeastern counties (which
have been all rain so far) will begin to acquire thermal profile
supportive of a wintry mix and then snow overnight just in time
for the concluding/back side of the precipitation shield.
Surface temperatures are expected to fall well below freezing
for most of the region tonight, and nighttime lows have been
significantly lowered. Freezing of slush and meltwater on roadways
is certain; thus, travelers should be alert for hazardous travel
conditions tonight into Saturday morning. Additionally, trees,
tree limbs and power lines may go down due to the weight of snow.
Many County Emergency Managers and local police have urged
citizens to travel only if necessary overnight.
