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000
FXUS62 KRAH 180542
AFDRAH

Area Forecast Discussion
National Weather Service Raleigh NC
142 AM EDT Wed Oct 18 2017

.SYNOPSIS...
Surface high pressure over the Mid-atlantic will extend across
the region into the weekend. A cold front will approach the
area from the west early next week.
&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 920 PM Tuesday...

Absolutely ideal radiational cooling conditions this evening are
paying dividends with the temperatures so far as some low to mid 40s
are already showing up in the rural areas. The 00z observed sounding
was incredibly dry this evening and GSO is still exhibiting a 10
degree surface dewpoint depression. That dryness may mitigate any
frost potential overnight although temperatures should get cold
enough especially in northern and western rural areas. As a result
have put patchy frost in the forecast but with low confidence and
the short lived nature of the event, have continued to the decision
to hold off on a frost advisory. Regardless, if you have unusually
susceptible plants, covering them would be a good idea. Lows will
bottom out in the upper 30s to low 40s in most locations with a few
mid 30s scattered in.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM THURSDAY/...
As of 140 PM Tuesday...

Basically a temperature forecast with gradual airmass moderation as
center of surface high shifts east from the lee of the
central/southern Appalachians Wednesday morning to off the Mid-
Atlantic Coast Wednesday afternoon/evening. Highs Wednesday a good 5
degrees warmer than Tuesday, ranging from upper 60s to lower 70s.

A low-amplitude shortwave trough approaching the area late Wednesday
night may produce some patchy thin cirrus, but otherwise prove to be
inconsequential. Lows 40 to 48.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
As of 255 PM Tuesday...

High pressure will dominate through the weekend, with a very gradual
warming trend through the period. Highs will be mostly in the mid to
upper 70s, with perhaps some lower 80s Saturday and Sunday. Mins
will be mostly in the mid 40s Friday morning warming to the upper
40s to lower 50s by Sunday morning.

The high pressure will shift offshore and we have a favorable return
flow setting up ahead of our next frontal passage. Timing will be a
key player early next week, as an upper trof moving east across the
southern Midwest will cut off over the gulf states, assisting in
providing strong moisture advection ahead of associated surface cold
front. The chance of showers will increase by later Monday, with
even better chances on tap for Monday night into Tuesday. Slightly
delayed timing would be beneficial, as it would allow us to build up
stronger instability to invigorate convection ahead of the front on
Tuesday. Highs Monday will reach the mid and upper 70s, while
Tuesday`s highs will be dependent on frontal passage...probably see
70s again, but could see cold air advection halt the morning warmup
early in the northeast.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
As of 140 AM Wednesday...

High confidence of VFR conditions through the 24-hour TAF
period. Surface high pressure and weak ridging aloft will result
in generally clear skies and fair weather. Light northeast to
easterly surface winds will range between 4 and 8kts today with
very light to calm winds expected early this morning and again
tonight.

Looking beyond the 24-hour TAF period, surface high pressure
will persist across the region into the weekend. Some patchy
stratus or fog is possible across the Coastal Plain impacting
the KFAY/KRWI around and just prior to daybreak on Thursday and
possibly Friday mornings. -Blaes
&&

.RAH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...BLAES
NEAR TERM...RE
SHORT TERM...CBL
LONG TERM...MLM
AVIATION...BLAES