Area Forecast Discussion
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FXUS62 KRAH 282250
Area Forecast Discussion
National Weather Service Raleigh NC
650 PM EDT TUE JUN 28 2016
A cold front will progress through central NC overnight, then stall
near the coast Wednesday. The front will begin to return northward
as a warm front on Thursday.
.NEAR TERM /THROUGH TONIGHT/...
As of 600 PM...
The main weather hazard tonight will be fog, with a potential of
dense fog over the eastern Piedmont and Coastal Plain later tonight
as the cold front stalls.
The widespread showers have pushed to the coast with lingering
scattered showers lingering as far west as Raleigh and Fayetteville
as of 600 PM. The skies were slowly clearing from NW to SE through
the Piedmont. This clearing process will be slow but will make into
through much of the eastern Piedmont by late evening. This will
occur as a cold front slows as it pushes into the NW Piedmont. The
front and the clearing process will stall over the eastern sections
including the Coastal Plain overnight.
With at least some clearing expected to push into the Triangle and
Fayetteville areas, patchy dense fog appears likely overnight. This
is due to the clearing skies, calm conditions, and saturated ground
from the 1 to locally 3 inches of rain today.
We will update the Hazardous Weather Outlook to add the possibility
of dense fog for the Triangle, Fayetteville, and Goldsboro later
Lows generally 65-70.
.SHORT TERM /wEDNESDAY THROUGH WEDNESDAY NIGHT/...
As of 330 pM Tuesday...
The cold front currently moving through PA/WV/KY will move into
central NC later tonight and effectively stall across the CWA on
Wednesday. With a temporary reprieve from the 2 inch PW plume,
guidance suggests much more isolated convection during the
afternoon, confined mainly near and southeast of the boundary,
where modest CAPE will remain present given dewpoints in the upper
60s to around 70. However, a speed max currently over the
northern Plains will dive south across the Appalachians by late
afternoon, with modest pressure falls on the 1.5 PVU surface,
suggesting a decent upper tropospheric wave that could induce more
convection than the models indicate. This would also likely enhance
deep layer shear and severe potential. highs will be near normal,
Late afternoon convection in the mountains may roll into the
western Piedmont during the evening but should generally
dissipate as it moves into the less favorable and drier airmass
in the Piedmont. Will maintain just a slight chance of a storm
overnight given the presence of the aforementioned boundary, with
lows in the mid and upper 60s.
.LONG TERM /THURSDAY THROUGH TUESDAY/...
As of 330 PM Tuesday...
The stalled boundary over NC on Wednesday will drift back to the
north on Thursday, with yet another disturbance progged to move
through the base of the broad upper trough over the eastern US.
This should again provide some enhancement to diurnal convection
and mid-level flow, resulting in scattered convection and isolated
severe storms. Beyond Thursday, the upper trough will continue to
be reinforced by low-amplitude shortwaves, with the stalled
frontal zone (reinforced by Saturday) meandering over the region.
Models indicate a pair of disturbances on Saturday and Sunday that
may lead to the best chance of diurnal enhancement of convection,
and given PW still near 2 inches and multiple rounds of precip,
there could be a minor flooding threat to evolve over the weekend
or even into early next week. Temps will be within a few degrees
of climo for most of the extended period.
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
As of 650 PM Tuesday...
24-hr TAF Period: Sub-VFR conditions associated with lingering
shower activity at eastern terminals (KRDU/KFAY/KRWI) are expected
to lift to VFR by or shortly after 00Z (beginning of the TAF period)
as showers dissipate and shift toward the Carolina coast. At the
KINT/KGSO terminals where minimal rainfall occurred today, a dry
airmass remains in place in the lower levels, and it is unclear
whether or not fog or low stratus will develop prior to sunrise Wed.
Further east at KRDU/KFAY/KRWI where persistent rainfall during the
day has moistened the low levels, dense fog and/or low stratus
development is likely to occur once mid-level cloud cover
erodes/dissipates and skies clear from NW-SE during the overnight
hours. Some uncertainty persists w/regard to the precise
timing/degree of clearing, however, confidence is sufficient to
indicate deteriorating conditions at eastern terminals between
midnight and sunrise Wed. Conditions are expected to rapidly improve
within several hours after sunrise Wed, with VFR conditions at all
terminals by 13-15Z. Isold to sct convection cannot be ruled out
across portions of central NC near the end of the 00Z TAF period,
however, confidence is insufficient to warrant mention at this time.
Looking ahead: With broad cyclonic flow aloft expected to prevail
this week, expect a daily potential for late afternoon/evening
(primarily) convection and morning stratus/fog, especially at
terminals affected by convection during the prior aft/eve. -Vincent