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This is from 1025pm (waiting on the update)

Friday, a cold front riddled with convection will work through the
CWA from west to east. I have high confidence that everyone will see
rain, starting in the northwestern counties during the morning, then
reaching the eastern areas by afternoon. We are still 2 days away
from the event, so there could be some adjustments needed to the
timing.

As far as the severe threat is concerned, the current slight risk
from SPC looks like the most reasonable course of action this far in
advance. However, it would not surprise to see the enhanced risk
expanded westward by at least a couple of tiers of counties when the
new Friday forecast from SPC comes out overnight. Shear looks to be
very strong Friday, with the area in the favorable quadrant 100+
knot jet at 500 mb. Instability will be modest because mid lapse
lapse rates will only be seasonable, but it won`t take a ton of CAPE
to cause problems given the expected bulk shear. The biggest area of
uncertainty lies with the convective evolution, as well as the
mesoscale high/low couplet that should form with forcing this
strong. The GFS is not picking up well on this, whereas the 00Z/06Z
ECMWF and the 12Z hi res guidance do have a reflection of this
evolution. If the ECMWF/NAM solution is correct with the mesolow
moving north northeastward bisecting the CWA on Friday, areas along
and east of the mesolow track will have an enhanced risk of severe
weather, including tornadoes, due to increased low level helicity,
increased surface convergence, and the potential for stronger rear
inflow jets behind any bow echos that form. Unfortunately, our
models are simply not good enough yet to forecast the exact
evolution of these features 48 hours in advance, so we just have to
mention the possibility in our discussions and hope we can refine
things more as we get closer to the event.

There will also be some heavy rain with the front as PWs increase to
1.5+ inches under strong divergence aloft. At this time, excessive
amounts do not seem likely due to the quick speed of the front, but
local issues may arise that could require flood advisories, or
possibly a warning or two in our flashy areas.

One other issue Friday will be the winds ahead of the front. Given
the strong winds expected at 850 mb, we will likely have strong
enough winds mixing down to warrant at least a Lake Wind Advisory, if
not a full on Wind Advisory.

 

 

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8 minutes ago, downeastnc said:

There are a ton of reasons to not buy in totally to the NAM, but even if its over done by half thats still a rough day.....really I think its a safe bet that at the minimum we see several broken line segments all of which will produce severe criteria wind gust over a fairly large area, it should not be hard to get some impressive winds to the surface given the wind field aloft......the real question is do we get enough instability to fire those semi discrete supes with a leeside surface low.....

Yeah but when the EURO backs it up?...

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7 hours ago, Orangeburgwx said:

Yeah but when the EURO backs it up?...

In my experience any time you have clouds and rain before the main storms are suppose to arrive the severity of the event is questionable. It takes a great setup to get widespread severe in those situations but it does and can happen. Just gonna be a wait and see kind of thing. 

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The latest briefing from NWS Raleigh shows the timing for central NC being between 1PM and 8PM.

Though, looking at the latest NAM3K and HRRR, there appears to be some convection, perhaps discrete, popping up around 9-10AM.    Anyone else seeing this?

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The latest briefing from NWS Raleigh shows the timing for central NC being between 1PM and 8PM.
Though, looking at the latest NAM3K and HRRR, there appears to be some convection, perhaps discrete, popping up around 9-10AM.    Anyone else seeing this?


Yeah and even some rolling in before that around 3AM.


.

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The NAM looks nasty. But as has been aforementioned, is it trustworthy? Should we get a separate thread going for tonight/tomorrow though? Or are we waiting to see what happens with the later guidance?


.

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RAH:

The s/w exiting the Deep South early Friday will phase with another 
(though weaker) s/w in the northern stream and lift newd across the 
Carolinas Friday afternoon, taking a slight negative tilt as it does 
so. Surface based instability has trended more unstable compared to 
36-24 hours ago with the NAM depicting MLCAPE values between 500 and 
1000 j/kg over the region by mid day. While the kinematics not as 
impressive as last Friday, presence of 35kts low level jet and 
central NC in the nose of a 100+kt upper jet will provide enough 
shear and lift to generate thunderstorms, some of which could be 
strong/locally severe. The main severe weather hazard will be 
locally damaging straightline winds. Based on current timing, the 
threat for a strong/severe storm will be mainly across the eastern 
Piedmont, Sandhills and the Coastal Plain during the afternoon 
hours. 

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day2otlk_1730.gif?1556214295524

1:30pm SPC update:

...Carolinas to the Middle Atlantic region...

   Southern-stream shortwave trough will deamplify as it becomes
   absorbed within the base of an amplifying northern-stream trough and
   move off the Atlantic Seaboard early Friday. The northern-stream
   trough will continue through the Carolinas and Middle Atlantic
   region during the day accompanied by a cold front. Modest low-level
   moisture with dewpoints in the upper 50s to lower 60s F will advect
   through the warm sector along a 50 kt low-level jet. This in
   conjunction with some cloud breaks will destabilize the boundary
   layer with MLCAPE from 500-1000 J/kg possible. Some thunderstorms
   may be ongoing along the NC coast early Friday in association with
   the leading shortwave trough. Farther upstream, storms are expected
   to intensify along and ahead of the cold front as the boundary layer
   destabilizes from VA into NC and possibly as far south as SC.
   Strengthening mid-upper wind profiles accompanying the
   northern-stream shortwave trough will support 40-45 kt effective
   bulk shear supportive of embedded organized structures with storms
   developing within the evolving squall line and some supercells with
   any storms developing ahead of the line. Damaging wind appears to be
   the main threat,  but isolated tornadoes are also possible. Severe
   threat should end by early evening as the cold front moves offshore.

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Coming in at peak heating...

RAH:

Showers and scattered storms moving into the W CWA at the start of 
this period are expected to grow upscale and strengthen as they head 
E through Fri afternoon and encounter increasing diurnal 
destabilization within a background of strengthening deep layer 
shear. A nose of 50-60 kt mid level winds will spread in during the 
afternoon, just behind a 40-45 kt SW 850 mb jet and beneath 
strengthening upper divergence along and just ahead of the trough 
axis. These improving kinematics in conjunction with marginal to 
moderate destabilization should facilitate organization of 
convection into a wavy line or bowing segments capable of producing 
pockets of straight line wind damage, with a lesser risk of a weak 
tornado or two. The primary threat will be in the afternoon, 
decreasing by early evening as the surface cold front sweeps to our 
E and brings about late-night W-to-E clearing. Highs should range 
from the lower 70s NW, a minimal diurnal rise due to the clouds and 
precip, ranging to the upper 70s/near 80 E. With cold air advection 
Fri night, lows should be in the upper 40s to lower 50s. Frequent 
gusts to 25-30 kts are expected with SW surface winds ahead of the 
front, with gustiness lingering into early evening immediately 
behind the front as winds veer to W and WNW. -GIH

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I know this isnt covering the Triad, but dang it sure feels like a thunderstorm kinda day.  I just need some rain.....cant believe I just said that.

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From RAH:

As of 256 PM Saturday...

The main concern the rest of today is the svr tstm potential assoc 
with the line of storms presently moving across E TN and W NC, along 
with the discrete cells out ahead of the line. Latest mesoanalysis 
shows 1500+ J/kg ML CAPE across a large portion of our CWA, while 0-
6km bulk shear is in the 25-30kt range, supportive of multicell 
clusters/line.  The latest near-term CAMS, including the HRRR, 
suggest the main line will sweep across central NC, first reaching 
the Triad and our western zones between 5-7 PM, the Triangle region 
and US-corridor between 7-9 PM, and the I-95 corridor and coastal 
plain between 9 PM and midnight.  Of course the isold-scat cells 
ahead of the main line will arrive earlier.   The main hazard assoc 
with this activity is damaging straight-line winds, although some 
hail is possible with the earlier discrete cells. 

Then later tonight, another round of showers and perhaps tstms will 
move across central NC, this activity associated with the tstm 
complex currently moving across MS and AL.  The HRRR suggests that 
this activity will sweep across central NC during the overnight 
hours.  The svr potential will be limited however, since most of the 
CAPE should have been consumed by them thanks to the activity 
earlier in the evening.  Nevertheless, heavy downpours will be 
possible, so will have the watch out for the potential for localized 
poor drainage flooding, which at night is always a heightened 
concern.  Lows tonight in the 60s. 

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Slight risk up for Sunday so I guess we will see how much instability we can get going.

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132 PM EDT Sat May 11 2019

The National Weather Service in Greenville-Spartanburg has issued a

* Tornado Warning for...
  Southeastern Cleveland County in the Piedmont of North Carolina...
  Northeastern Cherokee County in Upstate South Carolina...

* Until 200 PM EDT.

* At 131 PM EDT, a severe thunderstorm capable of producing a tornado
  was located 6 miles southwest of Shelby, or near Earl, moving east
  at 30 mph.

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216 PM EDT Sat May 11 2019

The National Weather Service in Greenville-Spartanburg has issued a

* Tornado Warning for...
  South central Gaston County in the Piedmont of North Carolina...

* Until 245 PM EDT.

* At 216 PM EDT, a severe thunderstorm capable of producing a tornado
  was located 7 miles west of Gastonia, or over Crowders Mountain
  State Park, moving east at 15 mph.

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Tornado Warning
National Weather Service Raleigh NC
451 PM EDT SAT MAY 11 2019

The National Weather Service in Raleigh has issued a

* Tornado Warning for...
  Northeastern Anson County in central North Carolina...
  Southwestern Montgomery County in central North Carolina...
  Northwestern Richmond County in central North Carolina...
  Southeastern Stanly County in central North Carolina...

* Until 515 PM EDT

* At 450 PM EDT, a severe thunderstorm capable of producing a tornado
  was located near Ansonville, or 13 miles north of Wadesboro, moving
  east at 25 mph.

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Didn't expect this today...

1022 AM EDT MON MAY 13 2019

The National Weather Service in Raleigh has issued a

* Tornado Warning for...
  Southwestern Nash County in central North Carolina...
  Northwestern Wilson County in central North Carolina...
  Northeastern Johnston County in central North Carolina...

* Until 1100 AM EDT

* At 1022 AM EDT, a severe thunderstorm capable of producing a
  tornado was located over Zebulon, or 18 miles east of Raleigh,
  moving east at 40 mph.

  HAZARD...Tornado and quarter size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without
           shelter. Mobile homes will be damaged or destroyed.
           Damage to roofs, windows, and vehicles will occur.  Tree
           damage is likely.

* Locations impacted include...
  Nashville, Wilson, Bailey, Spring Hope, Middlesex, Sims, Buckhorn
  Reservoir, New Hope and Tar River Reservoir.

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10 minutes ago, shaggy said:

Some monster hail being shown back near garner.

Largest hail I've personally seen at I40-Hwy42 Cleveland area. Golf ball with a few getting up to baseball range. 

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