Turner Downs Forecast Discussion

FXUS62 KRAH 031037

National Weather Service Raleigh NC
635 AM EDT Tue Aug 3 2021

A stalled surface boundary will remain along the coast through the
week, keeping a persistent chance of rain in the forecast for
several days. An upper level trough will contribute to much cooler
temperatures than normal today and tomorrow.


As of 245 AM Tuesday...

The forecast for today looks quite different than it did 24 hours
ago, or even 12 hours ago. The stalled front that has been across
the eastern Carolinas for the last few days will still be the main
player in the forecast, but all models, synoptic and convection-
allowing, have shifted the front farther east. While this will still
result in extensive cloud cover and cool temperatures across the
region, it will bring a lower chance of rain to every location west
of I-95.

Isolated showers have remained east of I-95 overnight, remaining in
the vicinity of the boundary. Precipitation will remain scattered,
but increase from southwest to northeast overnight as an upper level
shortwave moves across the Appalachians. Pops will be the highest
across western counties between sunrise and noon before diminishing
as the shortwave moves east. However, the entire precipitation
shield should be shifted east since the frontal boundary will be
farther east. Across an area from Burlington to Raleigh and Roanoke
Rapids, have dropped pops down to chance through the daytime. While
the previous forecast kept a slight chance of thunderstorms across
southern counties during the day, and an isolated elevated
thunderstorm could still occur, did not have enough confidence to
keep thunder in the forecast anymore, with barely any instability
present in model profiles. Despite less rainfall, models have not
backed off very cool temperatures for today. Record low maximum
temperatures will be threatened at all three climate sites, with
highs forecast in the 70s.

Similar to today`s forecast, models keep the forecast quite dry
tonight west of I-95. Pops were cut everywhere, and likely were not
cut enough, considering how little precipitation is shown by the
NAM, GFS, ECMWF, and HREF, especially in the Triad. Lows will be in
the mid 60s.


As of 245 AM Tuesday...

The changes to Wednesday`s forecast were not as dramatic as the
changes to today`s forecast, but nonetheless pops were cut once
again as the front will be closer to the coast. There are minimal
areas with likely pops east of I-95, but otherwise chance pops will
rule the day. Highs will inch up slightly, rising into the mid to
upper 70s. Expect little change Wednesday night, with chance pops
and lows once again in the mid 60s.


As of 320 AM Tuesday...

The upper trough over the Eastern US will begin to dampen while
lifting northeast and out of the area late Thursday/Thursday night.
Subtropical ridging will briefly extend over the SE US on Friday
before shifting offshore in advance of a mid/upper level trough that
will traverse the area late Saturday and into Sunday. In it`s wake,
a sprawling mid/upper level ridge encompassing much of the southern
CONUS will build east into the region and will become the dominate
weather feature next week.

Rain chances Thursday and Friday should largely remain confined to
eastern/coastal NC, INVOF the weakening surface front that will
remain pinned along the coast, with little of the way of PoPs west
of I-95. As of right now, it appears that the best chance for rain
area-wide will be on Saturday, owing to the approach of the
mid/upper level trough. Thereafter, rain chances will primarily be
diurnally driven.

Temperatures will moderate to near normal by the weekend and then
slightly above normal by early next week.


As of 635 AM Tuesday...

The 12Z TAF package will continue the trend of the 06Z TAF package,
showing slightly more optimistic conditions than were previously

INT/GSO should have a period of rain during the morning into the
early afternoon, with scattered showers during the afternoon and
drying conditions by nightfall. Unless the visibility drops in a
heavier rain shower, VFR conditions are expected through the TAF

It still appears that RDU may have minimal rainfall, although the
potential for showers will be present through the entire TAF
package. Expect MVFR cigs to develop around sunset and fall to IFR
after midnight.

There is a stationary front that has been the primary focus for
showers over the last few days and will continue to be the focus in
the upcoming days across eastern NC. With FAY and RWI in proximity
to this front, prevailing rain was included at both TAF sites, with
widespread rain not reaching RWI until the early afternoon. Showers
will initially provide MVFR ceiling restrictions at both sites, and
both sites will eventually drop to IFR ceilings.

Outlook: The unsettled pattern will persist throughout the forecast,
following a little bit more of a diurnal cycle along the stalled
boundary near the coast. Wednesday should only have scattered
precipitation, but showers are likely at RDU/RWI/FAY Thursday
through Saturday (with a chance of showers at INT/GSO those three




NWS RAH Office Area Forecast Discussion