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Area forecast discussion 
National Weather Service Raleigh NC
955 am EST sun Feb 14 2016

Synopsis...Arctic high pressure will extend across the area today.
A developing storm system will approach from the west tonight and
move eastward across the region Monday through Tuesday. High
pressure will gradually build in from the northwest Tuesday night
and Wednesday.


Near term /through Sunday/...
as of 955 am Sunday...

Very few changes are needed with the forecast this morning... mainly
a tweaking of today's highs and a slight slowing of the arrival of
cloud cover based on morning trends. High resolution guidance still
supports highs today from 29-36... coldest in the northeast beneath
the core of the Arctic surface ridge centered over far eastern Virginia...
despite plenty of sunshine for at least the first half of the day.
Middle clouds are projected to spread in from the west from late
morning through the afternoon... with most places mostly cloudy by
late afternoon. The forecast for the upcoming storm still looks on
track... and while we may see some returns on radar as soon as late
afternoon / early evening... these hydrometeors will initially be
fighting dry air near the surface and thus the forecasted onset of
measurable precipitation still looks good. We will be considering winter
weather advisories this afternoon... and perhaps a Winter Storm
Warning in the far northwest... after a thorough assessment of morning
model runs. -Gih

Here is the previous discussion from 4 am... today: modified surface
high pressure over the area this will begin to slowly slide eastward
towards the middle-Atlantic coast this evening... with middle and high
level cloud covering increasing ahead of the next system. Afternoon
low level thickness values are expected to be well below normal...
generally in the 1250s and 1260s. This combined with the increasing
cloud cover will lead to another cold day across the area... with
highs expected to be generally range from around 30 north/NE to near 35

Tonight through Monday night: surface high pressure will shift
offshore tonight... while low level moist advection will commence
over top the lingering cold dome leading to the develop of some
light wintry precipitation. Precipitation is expected to first develop
across the northern/northwestern Piedmont initial very late this
evening/after midnight tonight (generally in the form of light snow
to start)... then filling in further south and east during the early
morning hours of Monday. This will result in the development of an
insitu cad wedge.

While the precipitation will generally remain light tonight into Monday
morning... the cold surface airmass deposited by the modified Arctic
surface high will lead to all precipitation early Monday morning falling in
the form of a wintry mix... with more snow/sleet across the
northern/northwest Piedmont.... to more of a sleet freezing rain mix
across the far south/southeastern counties. Given the surface high
will be transitory (continuing to move further away and offshore)
coupled with a surging warm nose expect we will see precipitation go from a
wintry mix to freezing rain... then all rain in a southeast to
northwest fashion on Monday. Expect locations across our far
southern and eastern counties will be all rain/drizzle by around
noon Monday... with the Triangle area turning to all rain/drizzle by
middle afternoon or so...while The Triad may hold onto some light
freezing rain or drizzle into the evening... before becoming all
rain by late evening. Most of the precipitation by midday Monday is
expected to be quite light... as the 850mb warm front lifts to the
north of the area. This should leave central NC will spotty light
precip/drizzle. With respect to to accumulations. Locations across the northwest
Piedmont/northern Piedmont will see the highest snow and sleet
totals... possibly 2 to 3 inches... with locations farther south and
east seeing less for a number of reasons (a little less quantitative precipitation forecast/less
time with higher snow/sleet to liquid ratios due to the warm
noes/and possible loss of saturation above -10c across the far
south/southeast). Thus... outside of the northwest/north Piedmont we will
generally see snow/sleet totals of around an inch or less. With
regard to ice accrual... think we should see at least trace amounts
across all of central NC... thus... at least a Winter Weather
Advisory will likely be needed in later shifts for the entire area.
Ice accrual is expected to generally be a tenth of an inch or
less... with the highest totals across the Piedmont. After
coordination with surrounding offices we will keep the current watch
as is for now. However... as mentioned above at least a Winter Weather
Advisory will be need for tonight into Monday for the entire area...
with perhaps a Winter Storm Warning needed for a the far north/northwest
Piedmont. Lows tonight are expected be in the lower to middle 20s. High
temperatures Monday will range from the lower 30s northwest to the lower to middle
40s southeast.

The main short wave energy and accompanying surface low are expected to
move through the area Monday night into Tuesday... with heavy rain
and possibly a few storms. Temperatures will increase ahead of the surface
low as the coastal front attempts to move inland. This will allow
for near steady to rising temperatures overnight... with lows for the
overnight period likely occurring at the start of the period. Temperatures
at around 12z are expected to be in the upper 30s northwest to the 50s southeast.


Short term /Tuesday and Tuesday night/...
as of 335 am Sunday...

Surface cold front attendant with the short wave crossing the middle Atlantic will
advance quickly eastward across central NC Tuesday morning. Numerous
showers ahead of this feature should quickly diminish west-to-east
through 17z. Westerly flow in the wake of this feature will also aid
to dissipate cloud coverage and lead to a fairly mild afternoon.
Afternoon temperatures should vary from the lower 50s northwest to the lower 60s

Another short wave will cross immediately north of central NC Tuesday
night...dragging a secondary cold front across our region. This
feature will basically be moisture starved though decent middle level
lapse rates may lead to a few sprinkles or light rain showers near
the Virginia border.


Long term /Wednesday through Saturday/...
as of 335 am Sunday...

Amplified l/west trough that has persisted over our region for much of
February will relax...leading to short wave ridging aloft by the end of the
week. This will lead to a deep zonal flow...initiating a return to
near normal and eventually above normal temperatures. Afternoon temperatures will
generally be in the 50s Wed-Fri. The approach of a surface cold front
from the northwest late Friday into Saturday will back the flow to a more
SW direction...pumping warm air residing over the deep south into
central NC. Afternoon temperatures Saturday should climb into the 60s
areawide. Overnight temperatures will generally be within a few degrees of
above freezing until late into the week when an uptick in cloud
coverage and a SW flow yields min temperatures in the 40s. Dry weather
expected through the period as moisture return will be characterized
as weak.


Aviation /12z Sunday through Thursday/...
as of 645 am Sunday...

An area of high pressure extending across the middle Atlantic and
Carolinas will maintain VFR conditions today. The high will drift
eastward and offshore later today. Thus...surface winds will gradually
veer from a northerly direction early this morning to an easterly
direction by this afternoon.

Middle-high level clouds will increase from the west later
today...and thicken/lower this evening. Areas of light snow will
develop across the Piedmont between 03z-08z...expanding into the
coastal plain and sandhills where it will mix with freezing rain
between 08z-12z. MVFR ceilings and visibility will be widespread
across central NC after 08z.

A mix bag of wintry precipitation will occur Monday morning with snow/sleet
and sleet across the northwest half...and freezing rain transitioning to
rain across the southeast half. The snow will become freezing rain then
rain across the northwest half Monday afternoon. Widespread MVFR/IFR
conditions will persist into Monday night as numerous showers cover
the region.

A cold front will cross central NC early Tuesday...bringing an
end to the rain showers. Improving aviation conditions
anticipated Tuesday afternoon and Tuesday night. VFR conditions
expected Wednesday into Thursday.



Here are the record lows and record low maximum temperatures for
Feb 14th.

Rec yr rec yr
low low maximum
02/14 6 1905 22 1914

02/14 -2 1899 27 1916

02/14 12 1968 33 1916


Rah watches/warnings/advisories...
Winter Storm Watch from late tonight through Monday evening for
Winter Storm Watch from Monday morning through Monday afternoon for



near term...Hartfield/bsd
short term...wss
long term...wss

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