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Area forecast discussion 
National Weather Service Raleigh NC
848 PM EDT Thursday Jul 28 2016

an upper level disturbance will track just to the north of the
region tonight around the hot high pressure over the
southeastern US. A surface trough of low pressure will stall across
the area through the weekend.


Near term /through tonight/...
as of 845 PM Thursday...

The excessive heat warning and heat advisory have been allowed to
expire as heat index values have dropped below critical limits.

The subtropical ridge in place over the southeast U.S. Has kept the
afternoon/evening showers and storms to the west and north of
central NC. Expect this will generally continue, though an isolated
shower and/or storm is still possible across far northern and
western reaches of the area (via outflow boundaries possibly making
it into the area from ongoing convection to the north and west of
central nc) for the next several hours. Otherwise, expect dry
conditions overnight, with low temps generally in the lower to mid
70s, with a few locations across the far southeast/east remaining in the upper
70s again.


Short term /Friday and Friday night/...
as of 320 PM Thursday...

Low-level thicknesses and heights aloft fall slightly on Friday as
the subtropical high shifts just east of the area and broad troughiness
begins to settle into the area from the west. However of more significance,
is the potential for dewpoints to mix out into the upper 60s and lower 70s
Friday afternoon owing to the low-level westerly flow that
develops in the wake of the surface low exiting off the mid-Atlantic
coast. So despite similar afternoon temperatures in the lower 90s northwest to upper
90s se, the drier air will suppress heat indices with current forecast
grids showing only the far southeast zones close to advisory criteria.
Confidence is too low at this time to warrant the issuance of an
advisory with this package so will let midnight shift re-evaluate.

Expect the westerly low-level flow east of the mountains to also suppress
convection Friday afternoon, maintaining isolated/slight chance of diurnally
driven convection.

Lows Friday night in the lower to mid 70s.


Long term /Saturday through Thursday/...
as of 250 PM Thursday...

The pattern for the long term period will feature a low amplitude
but broad trough across much of the eastern third of the country.
With our area on the eastern side of the trough axis during the
weekend, look for above normal temps to continue (low-mid 90s)
during that time, but daily diurnal rain chances should be at or
above normal (30-40% each day) given more abundant deep layer
moisture and a series of passing short waves embedded in the SW
flow. Perhaps the increased rain chances and assoc cloud coverage
may help mitigate the oppressive heat somewhat compared to what
we've seen the past few days.

For the early part of next week, the aforementioned trough axis is
progged to cross the eastern Seaboard. The assoc sfc cold front may
attempt to move across our area, setting up increased rain chances
for Monday. Assuming the front does indeed push south of our area,
we may see at least a brief return to normal temps (highs in the
upper 80s and lows in the upper 60s) during the mid-week period with
lower humidity and at or below climo pops.


Aviation /00z Friday through Tuesday/...
as of 815 PM Thursday...

VFR conditions are expected with some patchy early morning ground
fog possible late tonight. Scattered to isolated storms are possible
again tomorrow afternoon, but chances of a storm occurring at a taf
site are too low to include.

Outlook: outside of isolated to scattered storms each
afternoon/evening and some patchy early morning fog, expect
predominately VFR conditions through Friday. Rain chances are
expected to increase by the weekend and into early next week.


Rah watches/warnings/advisories...



near term...7/cbl
short term...cbl

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