Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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FXUS62 KRAH 250756

Area Forecast Discussion
National Weather Service Raleigh NC
356 AM EDT Mon Sep 25 2017

High pressure centered over the Great Lakes and northern Mid
Atlantic states will extend south into our region today. Hurricane
Maria is forecast to move north through the western Atlantic,
paralleling the SE Coast through midweek.


As of 305 AM Sunday...

High clouds continue to stream into the area this morning in
association with Hurricane Maria, which is located well off the
southeast U.S. coast. Meanwhile, surface high pressure will continue
to extend into the area from the north today. This will yield a
continuation of dry conditions, though increasing cloud cover, with
even some lower clouds moving into eastern portion of the area
today. In addition, the pressure gradient between the high to our
north and Maria will also begin to tighten, producing wind gusts in
the mid to upper teens across the area. High temps are expected to
range from the lower to mid 80s east to the mid to upper 80s west.

Low level moisture will further increase across the area, especially
eastern portions of central NC tonight as Hurricane Maria slowly
lifts northward offshore of the Carolinas. This will allow for some
low stratus to spread eastward into central NC, though generally dry
conditions are expected to continue. Low temps are expected to be in
the mid to upper 70s,


As of 325 AM Monday...

Hurricane Maria is expected to slowly lift northward, while
remaining a couple hundred miles off the NC coast. Thus, central NC
will remain well west of the track of the hurricane, and resulting
see only minimal impacts. In fact most locations across our a
forecast area will remain dry, with only a few light shower
associated with some weakening outer bands possible Tuesday-Tuesday
night across our far eastern Coastal Plain counties. The main
impacts will be mostly cloudy to overcast skies and some breezy
winds, with gusts of up to 30 mph or so (mainly across the Coastal
Plain and eastern Sandhills - generally along/near the I-95 corridor
and eastward). High temps are expected to be in the lower to mid 80s
and lows in the upper 60s to near 70.


As of 355 AM Monday...

Hurricane Maria is forecast to pass about 125-150 miles east of KHSE
on Wed, with merely a slight chance of a shower and wind gusts up to
25-30 mph in the Coastal Plain - very little impact on the sensible
weather in central NC. The bigger story Wed will be a return to
summer-like temperatures, about 10 degrees above avg, in the upper
80s to lower 90s. Lows around 70.

Meanwhile, a shortwave trough now over the cntl Rockies will lift
newd across the upr Great Lakes and sern Canada. An accompanying
surface frontal zone will settle through NC late Thu and Thu night.
Deep layer flow will generally be nwly, overwhelmed by the
circulation associated with Maria; and that will limit low level
convergence along the frontal zone. As such, the front is expected
to be a dry one for central NC, with just a band of mid level
cloudiness likely to accompany the fropa. Near persistence
temperatures in the upper 80s to lower 90s Thu, followed by cold
advection-driven ones into the upper 50s to lower-middle 60s Fri

Weak high pressure will crest overhead during the day Fri, with
temperatures within a couple of degrees either side of 80 degrees. A
secondary nrn stream shortwave trough will amplify from s-cntl
Canada to the nrn middle Atlantic coast; and this will send a re-
enforcing, stronger surface front through NC Fri night. ~1030 mb, cP
high pressure will subsequently build from the Great Lakes to New
England, while ridging swd in the lee of the Appalachians. The
weekend is consequently expected to be much cooler, with highs in
the 70s and lows in the 50s. Any precipitation chances, in a long
fetch of moist, enely flow off the Atlantic, is expected to remain
along coastal areas.


As of 210 AM Monday...

24 Hour TAF Period: VFR conditions are expected to continue early
this morning through at least daybreak. A band of MVFR clouds of
around 1500-3000 ft are expected to spread eastward into eastern
portions of central NC. This may result in a period of MVFR cigs at
KFAY and KRWI from mid evening through late afternoon/early evening.
Further west, expect VFR conditions will continue as surface high
pressure extends southward into the area. Otherwise, expect dry
conditions to continue, with increasing northeasterly winds today,
with perhaps a few gusts into the 15 to 20 mph range as Hurricane
Maria slowly lifts northward off the southeast U.S. coast.

Outlook: The closer approach of Hurricane Maria to the coast will
bring chances for some shower activity as well as some lower
ceilings to the eastern portions of the forecast area Monday night
through Thursday.





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