Person, Granville, & Vance counties have been upgraded to a winter storm warning
895
FXUS62 KRAH 122031
AFDRAH
AREA FORECAST DISCUSSION
National Weather Service Raleigh NC
330 PM EST Fri Feb 12 2021
.SYNOPSIS...
A cold air damming surface high pressure centered over the NE United
States will continue to extend into VA and NC through Sunday.
Meanwhile a series of lows will form and track NE up the coast of
the SE US and Carolinas through the same period.
&&
.NEAR TERM /THROUGH SUNDAY/...
As of 330 PM Friday...
...A Winter Storm Storm Warning Has Been Issued for Va Bordering
Counties through Early Sunday...
...All other counties in the Advisory area have been extended
through Early Sunday...
A strong/mature CAD will remain in place across central NC through
Sunday, which will lock the cold air in place. A series of southern
stream shortwave troughs, a lead trough currently near the Rio
Grande/northern Mexico, with the trailing trough over Baja, will
eject ENE, becoming increasingly sheared once they reach the SE US.
In advance of these two shortwaves, a multitude of upper impulses
will move atop the cold air place, resulting in episodic overrunning
and WAA. These upper waves will also spawn a series of weak sfc lows
along a stalled front that extends from the GOM to off the mid-
Atlantic coast. The most prominent of those sfc lows, will
eventually become better organized off the NC coast late tonight
through Saturday night.
Next wave of forcing and precip is forecast to arrive after midnight
and will envelop the area through Saturday evening, before tapering
off. After another lull early Sunday, the next wave/round of lift
and precip will spread north into the area through the afternoon.
This time around the axis of heaviest precip will be focused across
the east-southern eastern NC, with lesser amounts to the west,
ranging from 1 to 2". This second soaking will likely lead to some
minor river flooding along portions of the Neuse and Tar river.
Temperatures across the area range from 30 to 33 north to 35 to 38
degrees. These temperatures are not going to fluctuate much over the
next 48 hours, likely a 1 to 2 degree variation between day and
night. Thus, the northern portions of the forecast are set-up for
another round of freezing rains, while southern portions will
continue to see all rain. Expect additional ice accumulations of 0.2-
0.25" across the far northern/VA bordering counties to 0.10-0.20
across the Triad, to a trace to 0.10" across the northern Triangle.
Given these ice amounts and expected impacts, have upgraded Person,
Granville, and Vance counties to a Winter Storm Warning. All
remaining counties in the advisory will remain unchanged. However,
it was decided to extend both the warning and advisory in time
through Sunday morning as the freezing rain threat will persist
through that time. The best time of seeing any ice accrual will be
during the nighttime/early morning hours.
Confidence is increasing that temperatures will finally warm above
freezing everywhere on Sunday, with highs ranging from mid 30s
across the north to lower 40s south.