Flash Flood Warning 23, NWS Raleigh, NC

427 
WGUS72 KRAH 171906
FFSRAH

Flash Flood Statement
National Weather Service Raleigh NC
306 PM EDT Sat Aug 17 2019

NCC067-171916-
/O.CAN.KRAH.FF.W.0023.000000T0000Z-190817T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Forsyth NC-
306 PM EDT Sat Aug 17 2019

...THE FLASH FLOOD WARNING FOR EAST CENTRAL FORSYTH COUNTY IS
CANCELLED...

The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed any remaining road closures.

LAT...LON 3618 8030 3616 8004 3604 8004 3606 8032

$$

Ellis

AREA FORECAST DISCUSSION
National Weather Service Raleigh NC
129 PM EDT Sat Aug 17 2019

.SYNOPSIS...
A weak nearly stationary front will remain draped across the area
through the weekend. Meanwhile, a developing area of weak low
pressure along the SE coast will track north up the NC coast late
tonight and into Sunday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1000 AM Saturday...

Morning update: Some improvement in the fog/low stratus this morning
but many sites still at LIFR conditions. GOES-16 visible satellite
shows some eroding from both the north and south but leaving a dense
area of stratus along the US-64 corridor. This improvement is
happening fairly quickly and daytime heating should increase, but
this will leave some differential heating boundaries that could
become a focus, especially across the southern counties later this
afternoon. Otherwise forecast holds. -Ellis

A weak/ill-defined wavering surface boundary will reside across the
area through the weekend. At the same time, a plume of deep tropical
moisture (PWATS +2.0")will continue to funnel north up the SE Coast
through the weekend. Meanwhile,  across the northeastern Gulf of
Mexico an upper level disturbance is garnering some attention with
this feature expected to lift to track north along the SE Coast
today and then up the NC coast tonight/early Sunday. Majority of the
NWP model guidance develops a weak low pressure circulation INVOF
the Georgia and Carolina coasts as the upper vortmax lifts north.
Strengthening low-level moisture flux convergence ahead and with the
sfc circulation is expected to enhance convection/rainfall along
coastal NC as early as mid to late morning and continuing into
tonight. Models keep the bulk of moisture  transport along and off
the coast, so expect a sharp QPF gradient across the far SE zones
with the potential for Sampson and Wayne counties to see as much as
a half inch or more.  Elsewhere, convective rain chances ill range
from isolated/slight chance, with perhaps a slight uptick in
coverage across the far NW zones in response to the upper impulse
currently over eastern TN/KY advancing east into the area.
Near storm environment is very similar to yesterday, supportive of
one or two pulse severe. Additionally the far SE counties could see
some locally heavy rain.

Highs in the upper 80s/near 90, except across the far SE zones where
rain and clouds will keep temps in the mid and possibly lower 80s.
Lows overnight in the 70s. -CBL

.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
As of 418 AM Saturday...

A Weak area of low pressure lifting up the NC coast is progged to be
exiting the area by late morning/midday. Thus, it could be a showery
start to the day across the far eastern zones. Otherwise, a zone of
subsidence in the wake of the system could stifle convection across
the area Sunday afternoon, keeping most of the area convection free.
Warmer on Sunday with highs 90 to 95, warmest across the
southwestern Piedmont. Lows again in the 70s.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 500 AM Saturday...

Through the extended period near normal heights are forecast
with weak upper level flow. During this type of regime, with
mainly weak forcing, have kept the forecast mostly trended
towards climo. The main exception to this is with an approaching
cold front at the end of the extended Thursday evening.

More into the details, the long term will open up with mid-level
ridging over the southwestern United States with most of the upper
level energy remaining over Canada. Another weaker mid-level ridge
will be located near Bermuda with North Carolina located in between
the two ridges. Monday through Wednesday multiple rounds of
weak PVA will traverse the region providing sufficient lift for
periods of showers and thunderstorms. PWATs will be between
1.80" and 1.95", or above the 90th percentile for this time of
year. Given the above, it is difficult to pick out exact timing
of showers and thunderstorms or dry periods, but there will be
breaks in the precipitation.

850 mb temperatures (forecast to be between 16/20 degrees C) and
1000/850 mb thicknesses (around 1420/1430 m) will all run above
normal during the Monday through Wednesday period keeping high
temperatures around 90 degrees, or slightly above normal, each
day. Low temperatures will also run in the lower 70s, or above
average.

Thursday into Friday an upper level low will deepen near the Hudson
Bay allowing a cold front to sweep across the Ohio Valley. Latest
runs of the ECMWF, GFS, and CMC all hang the front up near or north
of the VA/ NC border Thursday evening. This makes sense for
this time of year. The front will likely enhance shower and
thunderstorm development Friday as PWATs rise to above 2.00".
Due to the above have kept the chance of rain in through the
extended.

&&

.AVIATION /18Z SATURDAY THROUGH WEDNESDAY/...
As of 130 PM Saturday...

24 Hour TAF Period: VFR conditions across much of the area but a few
remaining areas of MVFR prevail. Much of the precipitation today
will be south of KFAY but will likely drift northward through the
day putting KFAY at greatest risk for significant rain out of the
major TAF sites. Isolated to scattered convection across the rest of
the area with KRDU the least likely affected. Overnight tonight
expect another round of fog and low stratus, but this time more
constrained to eastern areas. Conditions are expected to deteriorate
after 9z potentially lingering through 15z Sunday at KRWI which will
be the last location to recover as a low pressure system exits to
the northeast.

Long Term: In the wake of the exiting low, Sunday should be fairly
quiet with VFR conditions predominate. Through midweek will remain
unsettled with a few waves coming northward out of the Gulf of
Mexico and a frontal system developing off to the northwest. Expect
periods of convection with fog/low stratus prevalent at night.

&&

.EQUIPMENT...
Over the weekend, flights will be conducted on 12Z Saturday and
12Z Sunday.

&&

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

&&

SYNOPSIS...CBL/Badgett
NEAR TERM...Ellis/CBL
SHORT TERM...CBL
LONG TERM...Haines
AVIATION...Ellis
EQUIPMENT...RAH

Hazardous Weather Outlook
National Weather Service Raleigh NC
512 AM EDT Sat Aug 17 2019

NCZ007>011-021>028-038>043-073>077-083>086-088-180915-
Person-Granville-Vance-Warren-Halifax-Forsyth-Guilford-Alamance-
Orange-Durham-Franklin-Nash-Edgecombe-Davidson-Randolph-Chatham-Wake-
Johnston-Wilson-Stanly-Montgomery-Moore-Lee-Harnett-Anson-Richmond-
Scotland-Hoke-Cumberland-
512 AM EDT Sat Aug 17 2019

This Hazardous Weather Outlook is for central North Carolina.

.DAY ONE...Today and tonight.

The probability for widespread hazardous weather is low.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

No hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.

NCZ078-089-180915-
Wayne-Sampson-
512 AM EDT Sat Aug 17 2019

This Hazardous Weather Outlook is for central North Carolina.

.DAY ONE...Today and tonight.

Locally heavy rain of 1 to 2 inches is possible
today and tonight. Given the heavy rain that
fell yesterday, flooding of low-lying or poor drainage
areas is possible.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

Hazardous weather is expected at this time.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected at this time.