Area Forecast Discussion
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FXUS62 KILM 270116
Area Forecast Discussion
National Weather Service Wilmington NC
916 PM EDT TUE JUL 26 2016
High pressure will expand across the Carolinas, maintaining
uncomfortable levels of heat and humidity this week. Isolated to
scattered showers and thunderstorms are possible each afternoon
and evening. The chances increase heading into early next week.
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
As of 912 PM Tuesday...Storm complex currently rocking areas S
and SW of Raleigh, sparking a glittering night-time light show.
Whether this feature will muster up a way to reach into our
northern SE NC zones or not remains to be seen, but we will
retain a slight chance of TSTMS across that area in case it does,
or outflows trip off additional towers. A blazer of a day expected
tomorrow, and we are not talking about vehicle types. Hotter air
temps tomorrow coupled with similar absolute humidity will result
in not just advisories but potential `heat warnings`. Will await
full suite of 0z data to make the call as this will be akin to
splitting diamonds, 109 vs 110, where 110 or high requires a
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
As of 3 PM Tuesday...The mid level ridge offshore not only grows in
size but also a bit in strength during the short term. This will
bolster the already unseasonable heat. Heat Advisories appear a
certainty both afternoons. Heat Warning criteria could even be
briefly achieved over a small part of the area. Figuring out
convection is rather tricky, as there will certainly be ample
instability with such heat in place. However the suppressive effects
of the ridge will be in full force. Have opted to keep the very
small POPS inherited along the sea breeze both days but could just
as easily see how any radar returns yield only non-measurable
precip (likely what happened this afternoon just to our west).
.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 3 PM Tuesday...Mid level ridging at the start of the period
will be suppressed by 5h trough dropping into the KY/TN valley for
the weekend. The weakening of the 5h ridge in conjunction with
southwest flow around the western edge of the Bermuda High will
increase precip chances over the weekend and for the start of next
week. Both the Piedmont trough and the sea breeze will become active
with pop increasing from slight chc/chc Sat to high chc and possibly
likely late in the period. The increase in precip chances will be
accompanied by a decrease in high temperatures. Expecting above to
well above normal temps Fri afternoon, with heat advisories likely.
850 temps Fri afternoon will approach 23C, suggesting triple digit
temps away from the coast. High temps Sat through Tue will gradually
trend toward climo with lows through the period running 5 to 10
degrees above climo.
.AVIATION /01Z WEDNESDAY THROUGH SUNDAY/...
As of 00Z...Classic summer weather with Bermuda high pressure in
control. A decent subsidence inversion will keep convection at
bay, however a complex north of the region will drop southeast
overnight and may get close to our most northeast counties around
07Z. Southwest winds should stay up enough overnight with little
or no fog expected. Wednesday, another very hot day with isolated
convection by late afternoon. Gusty southwest flow by midday.
EXTENDED OUTLOOK...Isolated to scattered afternoon convection
through Sunday may create brief periods of MVFR/IFR. Otherwise
NEAR TERM /THROUGH TONIGHT/...
As of 916 PM Tuesday...Wind and waves manageable and unchanging
through the period. High pressure well offshore will sustain light
to moderate SW wind. Vast majority of wave energy tied to local
wind waves with dominant periods 3-4 seconds, negligible swell.
Little to no TSTM threat overnight within the 20 nm zone.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
As of 3 PM Tuesday...Piedmont trough could briefly veer winds to
westerly early Wednesday but SW should still be the flavor of most
of the day. Models have been wanting to increase winds (at least the
gustiness) and seas over the short term even though conditions don`t
seem to be changing much. In deference to guidance have showed this
trend but in a tempered fashion. That is, hard pressed to see WNA`s
4ft seas at 41010 and have capped at 3. For the actual forecast
zones these changes haven`t much effect other than to also cap seas
at 3 ft.
LONG TERM /FRIDAY THROUGH SUNDAY/...
As of 3 PM Tuesday...Bermuda High and Piedmont trough combo will
maintain southwest flow over the waters through the period. Speeds
will be in the 10 to 15 kt range, highest in the afternoon and
early evening. Seas will run 2 to 4 ft.