Hurricane Helene: Remnants Impact to Mid-Atlantic

[understudyhero]

9 hours ago, CAPE said:

Looking forward to a max half inch of gentle rain and periods of drizzle over the next 4 days. Good for the new grass.

I just realized the lawn crew fertilized our yard last week. By Monday this will be a jungle. 

[MN Transplant]

Tornado warning down by Roanoke

[high risk]

 

   Simulated reflectivities Friday don't look particularly impressive, but we'll be in a high PW environment for a chunk of the day, so some over performing rainfall totals are certainly on the table.

[mappy]

72/71 in OC at 1a. So muggy. 

[jewell2188]

Radar looks meh

[yoda]

FXUS61 KLWX 270759
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
359 AM EDT Fri Sep 27 2024

.SYNOPSIS...
Hurricane Helene has made landfall along the northeastern Gulf
Coast overnight, and is expected to quickly move into the
southern Appalachians and Tennessee River Valley today into the
weekend. Widespread rain is possible today, especially across
parts of Central Virginia. Chances for rain will linger into
early next week as an upper low remains overhead.

&&

.NEAR TERM /THROUGH TONIGHT/...
Hurricane Helene made landfall in the Big Bend of Florida this
evening. This storm has a forward propagation speed of nearly 25
kts.. which is near the upper percentile for tropical cyclones.
The upstream trough across the Lower Mississippi Valley is
pulling the cyclone quickly northward. The center is already
well into Georgia as of 03 AM with the outer rainbands making it
into Virginia thanks to jet support/WAA. Through the day today,
the remnants of Helene will continue to move northward, but get
pulled west slightly towards the trough. Other than another day
of cloudcover and highs in the 70s, Helene will bring several
hazards to the area:

- Heavy rain threat... Given the tropical airmass with PW values
  well above climo norms for late September (~1.5-2.2"),
  repeated rounds of moderate to heavy rain are expected today.
  The greatest coverage will be across a line from roughly
  Highland County, VA to Albemarle County, VA this morning. By
  this afternoon and into this evening, a broken line of
  showers/thunderstorms or several lines may develop, but
  coverage should be more scattered in nature. Given the SE`ly
  fetch off the Atlantic, abundant moisture is upsloping into
  the Blue Ridge and Alleghenies. The higher terrain of these
  locations have the greatest potential for Flash Flooding
  (especially where recent rains have exceeded 2-4"). Another
  2-4" look possible across the higher terrain of the watch area
  through this evening. Have maintained the Flood Watch for
  these locales. Further north and east, less forcing exists and
  lesser amounts of rain are expected.

- Strong Winds...The remnant wind field with Helene is
  extensive. As of 3 AM mesonets across the higher terrain of
  the Alleghenies and Blue Ridge are already gusting to 20-30
  mph. As the remnants move north through the morning and
  afternoon, the winds will increase across the Blue Ridge and
  Alleghenies. A core of 40-60 kts of wind at H85 is forecast
  across central VA that pivots into the Ohio Valley. There is a
  good amount of disagreement between models on how far
  northeast these winds make it into the local forecast area,
  especially at lower elevations. Have expanded the Wind
  Advisory in coordination with PBZ to our common border. Bufkit
  profiles suggest 40-45 kts should mix down around 2500 ft,
  with 45-50 kts closer to 3500/4000 ft. There is a better
  signal for downsloping west of the Alleghenies, but
  northwestern Garrett County could downslope as well directly
  west of Keysers Ridge towards Friendsville. The saturated
  ground will likely allow for trees to fall as well. Across the
  lower elevations and metros, gusts to 20-30 kts are possible.

- Severe Potential (including tornadoes)... By this afternoon, a
  broken line or broken lines of showers/thunderstorms are
  possible. The best overlap in instability/shear/SRH is across
  central VA. SPC has a Marginal Risk (Level 1 out of 5) that is
  tornado driven (2%). The further north into the forecast area,
  there is less instability. However, in tropical environments
  it does not take much instability. The one limiting factor is
  the forcing is definitely better closer to the center which is
  forecast to track well to the west.

The region will reside in a tropical airmass tonight with lows
only falling into the upper 60s in the metros with upper 50s
west of the Blue Ridge. Dew points will be near the air temp, so
fog formation appears rather likely. Rain chances look to be low
overnight with PWs actually decreasing heading into Saturday.

 

[Weather Will]

WB 6Z EURO through Monday evening and still raining....

[frd]

34 minutes ago, Weather Will said:

WB 6Z EURO through Monday evening and still raining....

How often is the Euro correct any more ?  Last storm predicted 2 inches of rain across DE. and nothing at most locations. 

[Weather Will]

5 minutes ago, frd said:

How often is the Euro correct any more ?  Last storm predicted 2 inches of rain across DE. and nothing at most locations. 

Other WB depictions of models are showing rain too...at this point just happy to see the soil stay moist for my new grass coming up.

[CAPE]

13 minutes ago, frd said:

How often is the Euro correct any more ?  Last storm predicted 2 inches of rain across DE. and nothing at most locations. 

It actually was among the best for my area. GFS was terrible. The primary issue lately is the atmospheric blocking pattern and how far north/east significant precip can make it. Your area has just been a bit too far NE. The situation is similar for the remnants of Helene. Overnight into tomorrow appears to be the best window, but forcing overall looks pretty weak over this way and points NE. A half inch is probably the upside here through tomorrow. We shall see beyond that as the low weakens and makes its way toward the coast.

[IronTy]

37 minutes ago, frd said:

How often is the Euro correct any more ?  Last storm predicted 2 inches of rain across DE. and nothing at most locations. 

That was when we were in a drought and needed rain.  Now that we're all getting sick of gloom and rain the euro is bound to verify when predicting more.  If anything the amounts will over-verify.  

[MN Transplant]

9 minutes ago, IronTy said:

That was when we were in a drought and needed rain.  Now that we're all getting sick of gloom and rain the euro is bound to verify when predicting more.  If anything the amounts will over-verify.  

Still in a drought here

[Bob Chill]

Gettin pretty nautical down here in Penhook. Def some gusts in the 30s last hour. Under a wind adv and flood/spinny watch. Mentions of landslides in the AFD. Lol. 

 

If things really start to rip I'll head over to sm mtn lake and get some pics. I'll be careful with the storm surge 

[Interstate]

7 minutes ago, Bob Chill said:

Gettin pretty nautical down here in Penhook. Def some gusts in the 30s last hour. Under a wind adv and flood/spinny watch. Mentions of landslides in the AFD. Lol. 

 

If things really start to rip I'll head over to sm mtn lake and get some pics. I'll be careful with the storm surge 

Congrats on your move.  I didn't know you moved from Gaithersburg

[Bob Chill]

19 minutes ago, Interstate said:

Congrats on your move.  I didn't know you moved from Gaithersburg

Thanks man! We absolutely love it down here. Feel completely at home and the people are wonderful. Need to change lanes? Oh, just use a blinker. Need to pull out in "traffic"?... first person that can make a space does with a wave. Loading lumber alone at the yard? Employees and customers together come over and help and there is no saying "no". After many decades in DC metro, you forget that the vast majority of people out there are truly kind and helpful. Sad but true for me. 

It's getting kinda hairy down here honestly. Flickering lights and long drawn out gusts last 30 mins. If it gets to damage level I'll take a vid and upload it

[WxUSAF]

Meso out for heavy rain and flash flood potential between Roanoke and Charlottesville 

[Jrlg1181]

44 minutes ago, WxUSAF said:

Meso out for heavy rain and flash flood potential between Roanoke and Charlottesville 

Getting the first real tropical like band here now in Waynesboro,  up to .76 on the day now...

[stormy]

4 minutes ago, Jrlg1181 said:

Getting the first real tropical like band here now in Waynesboro,  up to .76 on the day now...

Had an easterly gust to 28 in a moderate squall about 10 minutes ago.

[Jrlg1181]

Kind of looks like on radar the center circulation wobbled a bit farther north than expected near the SW Virginia border  b4 the NW move..

[batmanbrad]

any chance that heavy stuff near and to the west of Richmond might make it up into the DC metro area if it continues to move N or NNE this afternoon?

[Wxtrix]

 

[NorthArlington101]

any chance that heavy stuff near and to the west of Richmond might make it up into the DC metro area if it continues to move N or NNE this afternoon?

Pass. Have a Potomac River booze cruise tonight. I’m okay with drizzle… not so much the wrath of Helene

[TSG]

Getting absolutely hosed in Charlottesville. Flood warning up through 7pm.

Winds are notable as well, ~15G25 since this band arrived about an hr ago. very tropical out there

[nj2va]

Been raining most of the day at Deep Creek. Breezy with gusts near 40 mph. 

[TSG]

wow. stronger winds mixing down with these spotty showers moving through. was not expecting this much wind here

[high risk]

Convective elements should be rolling through the DC metro area early this evening.    While surface-based instability should be negligible, the low-level shear will be very strong with impressive hodographs.    I can't rule out a very brief spin-up, or at least a tornado warning or two necessitated by modest storm rotation, although the chances of reaching the ground are likely small unless the surfaced-based instability is slightly higher than progged.