Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC-- Remove Highlighting --
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FXUS62 KRAH 250854
Area Forecast Discussion
National Weather Service Raleigh NC
353 AM EST Sat Feb 25 2017
A strong cold front will push across the region this afternoon and
move offshore by early evening. Colder high pressure will blow into
the area later today and tonight. A warm front will approach from
the south late Monday.
.NEAR TERM /TONIGHT/...
As of 245 AM SATURDAY...
High pressure dominated the Coastal Plain, with a return southerly
flow confined to the western Piedmont early this morning. The main
cold front was located across central KY and TN SSW into MS. A
squall line was driving into the western slopes of the Appalachians.
The line is expected to weaken into a narrow band of
showers/isolated thunderstorms by 12z, when it will be nearing the
Blue Ridge. This update will raise lows this morning due to the
return flow keeping temps up in the west. Otherwise - no other
changes at this time.
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
As of 342 PM FRIDAY...
Deepening cyclone will lift north into Ontario and Quebec, with
attendant trailing sfc cold front crossing the area Saturday
afternoon/evening. With the better dynamics and deeper moisture
lifting off to the north, accompanying band of convection will
weaken across North Carolinas, with only isolated to scattered
convection skirting across the northern tier.
Temperatures will approach record territory once again, especially
across the south-southeastern tier where it will remain mostly dry.
Highs ranging from mid 70s NW to lower 80s SE. It will be breezy as
well, with sustained winds of 15 to 18 kts, gusting to 25 to 30kts.
As far as severe potential: Steep low-level rates from the
unseasonably strong diurnal heating along with mid-level lapse rates
of 6.8 to 7.50 C/Km will result in weak destabilization of 500 to
1000 J/Kg across central NC. Given impressive 50 to 60kts of
unidirectional shear, it will be possible to see an isolated strong
to severe wind gust across the northern tier.
Strong post-frontal dry cold air advection Friday evening/night
will result in abrupt clearing and seasonable overnight lows
in the lower 30s NW to upper 30s/near 40 SE.
.LONG TERM /MONDAY THROUGH FRIDAY/...
-- Changed Discussion --As of 350 AM Saturday...
A warming trend will commence on Monday as the surface high moves
offshore. However, cloud cover will increase across the area as a
deep southwesterly flow develops. While this will lead to a warming
trend it will also spell a return to unsettle weather with lots of
clouds and periods of showers/storms. The first such disturbance in
the southwesterly flow aloft is expected to move across the area
late Monday into early Tuesday morning. Expect we will see an area
of showers and perhaps a few storms move across the area during this
time. A general lull in precip is expected Tuesday afternoon into
Wednesday, before a more significant s/w is expected to cross the
area along with a strong cold front Wednesday night/early Thursday
morning. High temps ahead of the front area expected to be in the
60s and 70s, with possibly a few lower 80s across the southern and
eastern half of the area on Wednesday. Lows will follow the same
trend, generally in the upper 40s to 50s.
Dry weather is generally expected behind the front as surface high
pressure is expected to initially build into the area, before a
enforcing dry cold front moves across the area on Friday. High
temps behind the initial front late next week are expected to be in
upper 50s to 60s, with lows by Friday morning generally in the 30s.
High Friday are expected to be in the 50s to lower 60s.
-- End Changed Discussion --
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
As of 130 AM Saturday...
24 Hour TAF Period: Patchy sub-VFR conditions (MVFR-LIFR) are
expected to develop across central NC early this morning, mainly
across the eastern TAF sites (KRDU/KFAY/KRWI). Any sub-VFR
conditions that develop should quickly lift within an hour of two of
sunrise this morning, with increasing south to southwesterly winds
in advance of an approaching cold front. Expect winds to increase
into the 15 to 20 mph range by mid to late morning, with gusts of up
25-30 mph possible late morning into the afternoon. A cold front an
associated broken band of showers and storms will move across the
area this afternoon. The best convective coverage will be across
northern portions of the area, where we could see a few strong to
damaging wind gusts accompanying the strongest storms. Sub-VFR
conditions will be possible with any convection. Winds will veer to
westerly just behind a cold front that will cross the area
immediately behind the showers/storms, during the afternoon hours,
then to northwesterly. Wind will decrease to around 7 to 13 mph
range by this evening, with some gusts of around 20-23 mph still
possible through mid evening.
Outlook: High pressure will build in from the west tonight through
Sun, moving east and offshore 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.
Record highs for February 25:
Greensboro: 81 (1930)
Raleigh: 82 (1930)
Fayetteville: 85 (1930)