Area Forecast Discussion
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FXUS62 KRAH 260609
Area Forecast Discussion
National Weather Service Raleigh NC
105 AM EST Mon Feb 27 2017
High pressure will move in from the west today, then move offshore
later tonight and Monday. A warm front will approach from the south
late Monday, then move north of the region Tuesday.
NEAR TERM /THROUGH TONIGHT/...
As of 105 AM SUNDAY...
NW winds at 10-20 mph will continue to gust to 25 mph through 400 or
500 am, when they will be reduced to 5-10 mph. CAA will continue
overnight with lows generally above freezing (mid 30s) NW, ranging
into the 40s in the SE. Clear skies with the NW downslope flow and
the strong subsidence per latest observational data.
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
As of 315 PM SATURDAY...
Flow aloft will become quasi-zonal flow in the wake of upper trough
exiting the Mid-Atlantic region. High pressure building into the
area from the west will quickly move offshore late Sunday night, but
will maintain east to west surface ridging into Monday. This means
that the cooler-more seasonable air will not stay around very long.
Highs ranging from from mid 50s NW to around 60 SE.
Sheared shortwave energy ejecting eastward across the Lower MS
Valley in the progressive low-amplitude flow will bring an increase
in high clouds late Sunday night/early morning and could temper low
temps Sunday night. Lows in the 30s.
.LONG TERM /MONDAY THROUGH SATURDAY/...
As of 200 PM Saturday...
After the brief return to near normal high temperatures on Sunday,
we will have a progressive warm up back into the 70s through midweek
as high pressure moves offshore and southwest flow ensues. Moisture
will be on the rise, as will cloud coverage and the chance of rain
through the midweek period. Showers are expected as early as Monday
night in the west as a weak upper disturbance lifts northeast in
prevailing southwest flow aloft. It`s hard to find a really
confident feature that might enhance coverage Tuesday night through
Wednesday but we will be in the warm moist airmass with potential
for any passing weak impulse to kick off spotty showers. Will
maintain generally uniform low chance PoPs across the area pending
later model resolution of these impulses. Temps will be rebounding
on Monday into the 60s...with low to mid 70s on Tuesday and mid to
upper 70s on Wednesday.
A cold front driven by a rather strong shortwave moving into the
Ohio valley will provide a focus for a line of convection Wednesday
night in the west...with the convection moving east rapidly and
offshore by Thursday evening. The convection will be east of central
NC by early afternoon. This timing is not ideal to benefit from
maximized diurnal instability, but strong upper diffluence and the
low level convergence with a 50+ knot h85 jet will be sufficient for
inclusion of at least a modest chance of thunderstorms at this
point. Highs Thursday will be hampered by the onset of cold air
advection fairly early in the day, with western areas topping out in
the upper 50s...while the southeast might see some mid 60s.
Dry weather and a cooler airmass will be in place Friday and
Saturday, with highs both days mostly in the upper 50s to lower 60s.
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
As of 1220 AM Sunday...
24 Hour TAF Period: VFR will continue for the 24 hour TAF period,
high confidence, as surface high pressure moves across the region.
This will result in decreasing winds speeds early this morning out
of the northwest, generally into the 5 to 10 kt range, with clear
Northwesterly winds in the 6 to 11 kt range to start the day (with
possibly a few wind gusts into the teens during the morning hours)
will become light and variable by mid to late afternoon into the
evening, with mostly sunny/mostly clear skies expected (only some
high thin clouds possible).
Outlook: High pressure will move east and offshore Sun night, which
will bring VFR conditions through Mon. The next chance for sub-VFR
conditions will be Mon night, lasting through Tue night and perhaps
into Wed, as southwest flow brings in low level moisture and an
increased risk for showers, as well low stratus and fog, especially
dusk through dawn. A cold front passage late Wed night or early Thu
will bring a better chance for showers then.