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> Aug. 7-9, 2017 MidAtl/NE Nor'Easter, More rain!
kpk33x
post Aug 3 2017, 11:46 PM
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The last couple of model runs have been a lot of fun.

Euro, CMC and GFS all in agreement today that a nor'easter that we'd really like to see 4 or 5 months from now is instead going to come in early August.

00z GFS still has it. It almost appears that the remnants from the Aug 4-5 cutter get hung up in Colorado, but it gets going with a severe outbreak in Nebraska on the 6th that holds together into Missouri/Arkansas for a bit on the 7th before weakening. A weak LP appears over southern Indiana 12z on the 7th spreading rain in front of it as far east as I-95 in the Mid Atlantic. By midnight the low is sitting right over Baltimore and there is decent rain going on right where everyone seems to love it so much this summer...MD/DE/PA/NJ/VA. 6 hours later it is over NYC and 6 hours later over Boston and the rain hangs on in New England into the 9th. It seems as if it holds more precip over eastern Maine longer, and they are actually a little dry so they could use it.

On the 7th and 8th in the more southern areas and Apps and the 8th/9th in New England, clouds and rain hold the temperatures down. It appears NYC, DC and Baltimore will struggle to 70 one or two days, PA's in the 60s, meanwhile up here we will be in the 60s and maybe upper 50s.

From what I can tell, the 12z Euro seemed just a bit north of the GFS - maybe 50 miles - and CMC's 00z went south pulling it almost due east through VA and not curving NE until offshore, pounding the DC/Baltimore area with heavy rain but making it a quick hitter with overrunning portion mostly in NE. Of note CMC also shows the severe outbreak generating in Nebraska before going into Missouri/Arkansas over the next 6-12 hours on the 6th. CMC also warmer with closer to 80 on the 7th in the areas GFS has struggling to 70, the 8th is fairly chilly over the whole MA/NE with 60s and low 70s, while it rebounds into mainly 70s and even 80F in the southern MA on the 9th. This is a switch from the 12z CMC, which was similar to the GFS if just a little faster with it.

Now I know most summers are good for a cutoff or two from Memorial Day into mid June, or perhaps something stalls in August. Even hotter periods like July 1990 or August 2007 will have a rainy day with 60s breaking up the 90s, but this is the third event since the beginning of July like this. I can't imagine that its too windy an event - the lowest the LP gets on any model I saw was 998 when exiting stage right from Nova Scotia.


--------------------
Autumn 2017 - Mahomet, IL

First day with...
...Low below 40F:
...Frost:
...First sub-freezing low:
...Snow reported:

Foliage: Some color starting to show (Sept. 14)
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Undertakerson
post Aug 4 2017, 03:35 AM
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QUOTE(kpk33x @ Aug 4 2017, 12:46 AM) *
The last couple of model runs have been a lot of fun.

Euro, CMC and GFS all in agreement today that a nor'easter that we'd really like to see 4 or 5 months from now is instead going to come in early August.

00z GFS still has it. It almost appears that the remnants from the Aug 4-5 cutter get hung up in Colorado, but it gets going with a severe outbreak in Nebraska on the 6th that holds together into Missouri/Arkansas for a bit on the 7th before weakening. A weak LP appears over southern Indiana 12z on the 7th spreading rain in front of it as far east as I-95 in the Mid Atlantic. By midnight the low is sitting right over Baltimore and there is decent rain going on right where everyone seems to love it so much this summer...MD/DE/PA/NJ/VA. 6 hours later it is over NYC and 6 hours later over Boston and the rain hangs on in New England into the 9th. It seems as if it holds more precip over eastern Maine longer, and they are actually a little dry so they could use it.

On the 7th and 8th in the more southern areas and Apps and the 8th/9th in New England, clouds and rain hold the temperatures down. It appears NYC, DC and Baltimore will struggle to 70 one or two days, PA's in the 60s, meanwhile up here we will be in the 60s and maybe upper 50s.

From what I can tell, the 12z Euro seemed just a bit north of the GFS - maybe 50 miles - and CMC's 00z went south pulling it almost due east through VA and not curving NE until offshore, pounding the DC/Baltimore area with heavy rain but making it a quick hitter with overrunning portion mostly in NE. Of note CMC also shows the severe outbreak generating in Nebraska before going into Missouri/Arkansas over the next 6-12 hours on the 6th. CMC also warmer with closer to 80 on the 7th in the areas GFS has struggling to 70, the 8th is fairly chilly over the whole MA/NE with 60s and low 70s, while it rebounds into mainly 70s and even 80F in the southern MA on the 9th. This is a switch from the 12z CMC, which was similar to the GFS if just a little faster with it.

Now I know most summers are good for a cutoff or two from Memorial Day into mid June, or perhaps something stalls in August. Even hotter periods like July 1990 or August 2007 will have a rainy day with 60s breaking up the 90s, but this is the third event since the beginning of July like this. I can't imagine that its too windy an event - the lowest the LP gets on any model I saw was 998 when exiting stage right from Nova Scotia.

Here we go again with the Summertime Nor'easter. It will almost literally "kill" some folks if this keeps up and if we were to get shut out during the cold season. laugh.gif
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KENNYP2339
post Aug 4 2017, 04:06 AM
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This is very out of character summer pattern, I'm waiting for the dog to start meowing and the cat to start barking.
But it just goes to show what a stuck pattern can yield, hopefully we cash in on this in Nov, Dec, Jan and Feb.
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LUCC
post Aug 4 2017, 10:05 AM
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I know not for this thread but WOW.



--------------------

Winter '16-'17 Snow total: 22.5"
Winter '15-'16 Snow total: 30.5"
Winter '14-'15 Snow total: 41.5"
Winter '13-'14 Snow total: 62.0"
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so_whats_happeni...
post Aug 4 2017, 12:55 PM
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QUOTE(LUCC @ Aug 4 2017, 11:05 AM) *
I know not for this thread but WOW.


I have off this whole week so if this verifies with the Tropics I'm game and will be down in nc.


--------------------
Tylor Cartter

B.S. in Meteorology
Millersville University


Weather Observer:
KMDT: Harrisburg International Airport
KBWI: Baltimore/ Washington International Airport

Stratosphere Discussion:
2016/2017


AccuWeather Forum MidAtl/NE Snowfall Forecasting Champion Winter 2017
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kpk33x
post Aug 4 2017, 04:36 PM
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12z model update - this really is like a winter storm forecast with the models moving around

12z GFS was south of earlier runs, developing the low later (still with the severe component over Nebraska/Missouri) then shoving it east thru Maryland and Delaware then ENE. NYC and maybe coastal NE gets brushed with the edge, interior NE is dry.
12z CMC is north of previous runs and now resembles the GFS overnight, bringing it thru Mason/Dixon then NE along the coast, providing a good soaking to all the forum members who would just LOVE to see another one.
12z Euro appears to be north, cutting thru PA then off NE coast 24 hrs later.

The spread is reflected in my current local forecast with a 40-50% chance of showers and thunderstorms and temps in the 70s as they try to ride the fence until it gets a little closer.

My current nonscientific opinion is that we may see a more ENE track than NE as it appears the current system takes its sweet time exiting through the Maritimes. One would think that would force the next system more south. Weird though - the GFS gets the first system out faster yet that's the one going more east while CMC has it lagging but the 7-9th storm cuts more NE along the coast.

The 18z is running but we all know the 18z doesn't matter laugh.gif laugh.gif laugh.gif


--------------------
Autumn 2017 - Mahomet, IL

First day with...
...Low below 40F:
...Frost:
...First sub-freezing low:
...Snow reported:

Foliage: Some color starting to show (Sept. 14)
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kpk33x
post Aug 4 2017, 04:39 PM
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PS who in PA is going to hug the 12z GFS? Between the 7th and 19th, the only completely dry day for the state appears to be the 9th. The LR has likely a weak tropical storm hitting Louisiana and turning into a wet Apps runner and PA soaker.


--------------------
Autumn 2017 - Mahomet, IL

First day with...
...Low below 40F:
...Frost:
...First sub-freezing low:
...Snow reported:

Foliage: Some color starting to show (Sept. 14)
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MD Blue Ridge
post Aug 5 2017, 09:01 AM
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I had no idea October came in early August. The boss is already asking for a fire. No I say. Well struggle to hit 70F today. Looking through to 8/20 were going to struggle to get to 75F any day if model depictions are to be believed. Quite a summer.


--------------------
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Elevation: 1625'


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rtcemc
post Aug 5 2017, 09:16 AM
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QUOTE(kpk33x @ Aug 4 2017, 12:46 AM) *
The last couple of model runs have been a lot of fun.

Euro, CMC and GFS all in agreement today that a nor'easter that we'd really like to see 4 or 5 months from now is instead going to come in early August.

00z GFS still has it. It almost appears that the remnants from the Aug 4-5 cutter get hung up in Colorado, but it gets going with a severe outbreak in Nebraska on the 6th that holds together into Missouri/Arkansas for a bit on the 7th before weakening. A weak LP appears over southern Indiana 12z on the 7th spreading rain in front of it as far east as I-95 in the Mid Atlantic. By midnight the low is sitting right over Baltimore and there is decent rain going on right where everyone seems to love it so much this summer...MD/DE/PA/NJ/VA. 6 hours later it is over NYC and 6 hours later over Boston and the rain hangs on in New England into the 9th. It seems as if it holds more precip over eastern Maine longer, and they are actually a little dry so they could use it.

On the 7th and 8th in the more southern areas and Apps and the 8th/9th in New England, clouds and rain hold the temperatures down. It appears NYC, DC and Baltimore will struggle to 70 one or two days, PA's in the 60s, meanwhile up here we will be in the 60s and maybe upper 50s.

From what I can tell, the 12z Euro seemed just a bit north of the GFS - maybe 50 miles - and CMC's 00z went south pulling it almost due east through VA and not curving NE until offshore, pounding the DC/Baltimore area with heavy rain but making it a quick hitter with overrunning portion mostly in NE. Of note CMC also shows the severe outbreak generating in Nebraska before going into Missouri/Arkansas over the next 6-12 hours on the 6th. CMC also warmer with closer to 80 on the 7th in the areas GFS has struggling to 70, the 8th is fairly chilly over the whole MA/NE with 60s and low 70s, while it rebounds into mainly 70s and even 80F in the southern MA on the 9th. This is a switch from the 12z CMC, which was similar to the GFS if just a little faster with it.

Now I know most summers are good for a cutoff or two from Memorial Day into mid June, or perhaps something stalls in August. Even hotter periods like July 1990 or August 2007 will have a rainy day with 60s breaking up the 90s, but this is the third event since the beginning of July like this. I can't imagine that its too windy an event - the lowest the LP gets on any model I saw was 998 when exiting stage right from Nova Scotia.

Great write up KPK.
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risingriver
post Aug 6 2017, 09:46 PM
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Really could use the rain in Fredericksburg, Virginia but it looks like the main precip shield is going to go through Northern Virginia and DC/Baltimore again. We missed the majority of the rain last Nor'easter and even Friday's frontal passage was dry here, but windy on Saturday.

All of this troughiness plus with the tropics heating up means it could be extremely wet if we get a tropical system cruising up the coast along one of these troughs.

NWS issued flash flood watches for most of Eastern Maryland and DC already. Lately seems like every day somebody in that part of this area is dealing with three plus inches of rain and a short period of time.
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KENNYP2339
post Aug 7 2017, 04:06 AM
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Just started drizzling up here, hopefully we can squeak out more than a 1/2" of rain today, I need it for my new grass
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MaineJay
post Aug 7 2017, 04:38 AM
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Perseids should be firing up, keep an eye out. Tough moon, but don't let it deter. smile.gif

Hopefully coastal areas can squeeze out a half inch or so, they could use it.

WPC 48 hour QPF
Attached Image


3km NAM
Attached Image


12km NAM
Attached Image


GFS
Attached Image


QPF disco
QUOTE
PRELIM DAY 1...DAY 2 AND DAY 3 QPF DISCUSSION
VALID AUG 07/1200 UTC THRU AUG 10/1200 UTC
REFERENCE AWIPS GRAPHICS UNDER...PRECIP ACCUM - 24HR

DAY 1...

...TN VALLEY TOWARDS MID ATLANTIC...

THE MCV/SURFACE LOW WILL TRACK ACROSS KY EARLY TODAY...THEN OFF
THE MID ATLANTIC COAST MONDAY NIGHT. ANTICIPATE A BROAD AREA OF
RAINFALL WITH THIS FEATURE AS IT INTERACTS WITH A MOIST AIRMASS
AND THE UPPER JET TO THE NORTH. COMPARED TO THE PREVIOUS
FORECAST...THERE IS BETTER MODEL CLUSTERING WITH THE TRACK OF THIS
LOW AND THE AMOUNT OF HEAVIER CONVECTIVE ELEMENTS THAT WILL BE
EMBEDDED WITHIN THE BROADER RAIN SHIELD...THOUGH SOME LATITUDINAL
DIFFERENCES REMAIN WITH THE HEAVIER AMOUNTS FARTHER EAST ALONG THE
MID ATLANTIC COAST. WPC UTILIZED A MULTI HIGH-RES MODEL BLEND IN
GENERATING THE QPF...WHICH RESULTED IN AN AXIS OF 2-3+ INCHES FROM
EASTERN MD INTO DE AND SOUTHERN NJ. IT SHOULD BE NOTED HOWEVER
THAT A FEW PIECES OF THE HIGH-RES CAMs (NSSL-WRF AND NAM CONUS
NEST IN PARTICULAR) DEPICT A SECONDARY SWATH OF HEAVIER TOTALS IN
THE WARM SECTOR/SOUTH OF THE LOW TRACK INTO CENTRAL-SOUTHEAST VA.
GIVEN THE GREATER DEEP-LAYER INSTABILITY TO WORK WITH OVER THIS
REGION...CERTAINLY CANNOT DISCARD THESE HIGHER
TOTALS...HOWEVER...AT THIS POINT DO NOT EXPECT THE COVERAGE TO BE
AS EXTENSIVE COMPARED TO AREAS FARTHER NORTH CLOSER TO THE SURFACE
LOW TRACK.

PER COLLABORATION WITH WFOs LWX...AKQ...AND PHI...BASED ON THE
STRONG MULTI-MODEL SIGNAL...HAVE UPGRADED A PORTION OF THE SLIGHT
RISK REGION INHERITED FROM SUNDAY'S DAY 2 EXCESSIVE RAINFALL
OUTLOOK TO MODERATE...BASICALLY FROM DC-BALT EASTWARD THROUGH
EASTERN MD...DE... FAR SOUTHEAST PA...AND SOUTHERN NJ.

http://www.wpc.ncep.noaa.gov/discussions/h...php?disc=qpfpfd

I certainly wouldn't mind a few cloudy days, last week was basically total sun on the jobsite, didn't make it pleasant. Overall, it's been very "pedestrian" summer. smile.gif save that tornado outbreak, only real meteorological event of note thus far up my way.

GYX is brief, understandably so.
QUOTE
.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...
By tonight...the upper trof moves east and allows a surface low
to develop along the mid Atlantic coast then track to near Cape
Cod Tuesday morning. Showers...and a few thunderstorms...will
increase in coverage overnight with the heaviest rainfall over
southern and coastal sections. Precipitation tapers from
southwest to northeast Tuesday morning as the low and upper
trough slide well offshore.


https://forecast.weather.gov/product.php?si...p;highlight=off


--------------------
The Solar Eclipse is coming!! Thread

"z = z2 + c" - Benoit Mandelbrot

"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." - Albert Einstein
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MD Blue Ridge
post Aug 7 2017, 06:29 AM
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Sure looks to be a soaker. Currently dense fog and 59.5F. Edit that was min temp, now a balmy 60.9F.

This post has been edited by MD Blue Ridge: Aug 7 2017, 06:31 AM


--------------------
Blue Ridge Bouncer

Cascade, MD
Elevation: 1625'


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NorEaster07
post Aug 7 2017, 06:38 AM
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Feels like Sept/October talking about this with temps in 60s during the day.

NWS NY

Yesterday evening 9:52pm mentions the distinct difference betweeen models on where the low would track. (Less than 24hrs to go and it wasnt clear)


QUOTE
National Weather Service New York NY
952 PM EDT Sun Aug 6 2017

6 AM MONDAY MORNING THROUGH MONDAY NIGHT/..

Model guidance is still in two distinct camps regarding the
development and track of low pressure fcst to approach on
Monday, and pass over or just south of the area Monday night.
These differences have big impacts in terms of heavy rain and
isolated severe wx potential.

* GFS/GEFS continue to forecast a sfc low track farther south than
other guidance, which has worked out fairly well with recent
weather systems that have had more of a northern stream
influence.
* Both the SUNY SB NAM/GFS WRF support this idea.
* However, it is hard to ignore the stronger NAM/ECMWF solutions
which take the low from near or just west of Philadelphia 00Z
Tue, to across Long Island by 06Z Tue, to near or E of Cape Cod
by 12Z Tue.
* Latest SREF is in between these two extremes, and a
little slower than the GFS, and the GEFS is also a little
slower than the GFS.

With all that in mind decided to forecast a
compromise between these two camps until the situation becomes
more clear. This suggests better potential for heavy rain across
Long Island, possibly as far west as NYC and extending north
into SE CT.


If the low takes a track directly across Long Island, would also
have to worry about isolated flash flood/severe wx potential

Mon night in a low CAPE high shear environment, with very heavy
rain, damaging winds or a brief tornado possible. Attm best
chances for this per SHERB parameter appear to be just south of
Long Island--too close to call, and so have mentioned gusty
winds with any tstms from NYC east for Mon night..



This morning mentions its coming over the area. So looks like the NAM and ECMWF solution was right.

QUOTE
National Weather Service New York NY
556 AM EDT Mon Aug 7 2017

.SYNOPSIS...
An area of low pressure moves northeastward and deepens as it passes
through the area tonight. The low pressure system continues
northeastward towards Nova Scotia Tuesday while high pressure builds
into the region from the west. High pressure will continue through
mid week, then a trough of low pressure may be in the vicinity
Friday into Friday night. Weak high pressure will otherwise be in
place into the start of the weekend.

.NEAR TERM /THROUGH TONIGHT/...
Only minor updates to reflect current temperature and dew point
trends. Moisture appears to be advecting northward faster than
previously forecast.

Confidence is increasing in a heavy rainfall event this
afternoon into tonight as an area of low pressure intensifies as
it passes overhead.
At the moment, it appears there will be two
waves of heavy rainfall in response to unusually strong polar
jet streaks
for this time of year.


The first jet max exits to
the northeast this afternoon, placing the area in a favorable
right entrance region, which in combination with several
approaching short waves will enhance upward motion across the
area. Given the strong jet dynamics aloft, low level flow will
strengthen in response, allowing moisture to quickly advect
northeastward. PWAT values well over 2 inches are forecast by
tonight.

By tonight, the primary upper trough and attendant jet approach
the region, with upper divergence allowing a rapid deepening of
the surface low as it passes over the area. Although confidence
in heavy rainfall is high, there will be some variability in
rainfall totals depending on the exact track. Right now, have
gone with consistency with most models showing a track right
across Long Island
. This may allow for some instability and
potentially higher rainfall totals in any thunderstorms that can
develop. With the warm front across the area and strong
directional and speed shear, the coastal areas of NYC and Long
Island will need to be monitored closely as the warm ocean
waters may locally support cells capable of rotation and
perhaps a brief waterspout/tornado
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phillyfan
post Aug 7 2017, 08:58 AM
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Got over half an inch from early this morning already. In a break for now till later.


--------------------
Severe Weather 2017:

High Wind Watch: 2/13
High Wind Warning: 3/2
Severe T-Storm Watch: 2/25, 3/1, 6/19, 6/23, 7/1, 7/13, 7/20, 8/12, 8/18, 8/22, 9/5
Severe T-Storm Warning: 2/25, 2/25, 3/1, 6/19, 8/5, 8/12, 8/18, 8/19, 8/22, 9/5
Tornado Warning: 7/13
Flood Watch: 3/31-4/1, 4/6
Flash Flood Watch: 6/19, 7/14, 7/23-24, 7/28-29(Cancelled), 8/18
Flash Flood Warning: 7/13, 7/23-24, 7/28-29, 8/18, 9/5
Pea Size Hail: 2/25, 9/5

90 Degree Days: 17 / Heat Waves: 3
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MD Blue Ridge
post Aug 7 2017, 09:56 AM
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Thick fog. Just pouring. 62F. Have to believe will finish today with 1-2" of rain.


--------------------
Blue Ridge Bouncer

Cascade, MD
Elevation: 1625'


90 Degree Days in 2017: 0
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MD Blue Ridge
post Aug 7 2017, 09:57 AM
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This Hazardous Weather Outlook is for eastern West Virginia,
northern and central Virginia, and central and western Maryland
with the exception of Garrett County.

.DAY ONE...Today and Tonight

A Flash Flood Watch is in effect from 9 AM to 10 PM today and
tonight for the Washington DC and Baltimore MD metro areas as
well as southern Maryland. Though not as likely outside the watch
area, localized heavy rainfall may result in isolated instances of
flooding, mainly along and east of the Blue Ridge Mountains.


--------------------
Blue Ridge Bouncer

Cascade, MD
Elevation: 1625'


90 Degree Days in 2017: 0
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MD Blue Ridge
post Aug 7 2017, 10:00 AM
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I doubt northern MD will see any advection or storms after this first wave, but I think down around DC it will just keep coming.

An unusually good disco from Sterling:

NEAR TERM /THROUGH TONIGHT/...

Current forecast in good shape. Stationary front remains well
south of the area this morning. There are two areas of showers:
one moving into Delaware associated with isentropic lift, and
the other...a broad swath...moving across the forecast area
associated with a shortwave trough.

A developing surface low will pull the warm front northward
into Virginia. It`s uncertain if rain rates will be sufficient
to produce flooding (other than ponding) with this first wave.
Current evidence suggests hourly rainfall rates up to an inch,
which most of the area can handle. However, it will certainly
set the stage for any additional showers/storms later today.
And, any excessive rainfall that may occur would unfold in a
slower fashion, and would be better characterized as flooding.

What unfolds after this initial round is still a little
uncertain. There will likely be some breaks in the precipitation
but continued lift in the frontal zone with an approaching
upper trough and right entrance of a jet streak. North of the
front, which looks to bisect the area, conditions will likely be
stable and shower/storm development may be limited. To the
south, theta-e advection will help some with the recovery of the
airmass. Any enhanced convective elements in this airmass could
pose a gusty wind threat given enhanced low level and deep
layer shear. An isolated tornado can`t be ruled out due to
backed flow near the front.

The extent of uncertainty is best displayed by GEFS CAPE
plumes, which range from 200 J/kg to over 1600 J/kg later this
afternoon at IAD. Modified LWX RAOB based on breaks and
temp/dewpoint spread of 77/70. This does yield 1100 J/kg SBCAPE.
At this time, the best chance of any severe weather will be
across southern MD.

A second wave of low pressure will develop along the front as
it drifts to the south tonight. This may prolong the heavy rain
threat in southern MD. While this area will be less susceptible
to flash flooding overall, if multiple round of heavy rain
indeed occur, the Watch may need to be extended past 10 PM in
this area. The rest of the area should see an end to the rain
fall as drier air advects in behind the front, although cloud
cover likely lingers.


--------------------
Blue Ridge Bouncer

Cascade, MD
Elevation: 1625'


90 Degree Days in 2017: 0
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stxprowl
post Aug 7 2017, 10:28 AM
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Parts of MD and DE over 2' already. Flash flood warnings already posted.
https://www.wunderground.com/weather-radar/...0Laurel%2c%20NJ

http://www.weather.gov/phi/
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MD Blue Ridge
post Aug 7 2017, 10:30 AM
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Counties just to my north.

The National Weather Service in State College PA has issued a

* Flood Advisory for Minor Flooding in Poor Drainage Areas for...
Bedford County in south central Pennsylvania...
Franklin County in south central Pennsylvania...
Somerset County in south central Pennsylvania...
Fulton County in south central Pennsylvania...
Cumberland County in south central Pennsylvania...

* Until 100 PM EDT

* At 835 AM EDT, Doppler radar indicated a large area of steady,
moderate to heavy rain spreading northeast across the Laurel
Highlands and South-Central Mountains of Pennsylvania. This
rainfall will cause minor flooding of some small streams and
creeks that are already running high or near bankfull. Minor
flooding of adjacent low-lying terrain, and poor drainage areas in
towns is also expected.

* Some locations that will experience flooding include...
Waynesboro, Somerset, Breezewood, Carlisle, Chambersburg, Lower
Allen, Enola, Shippensburg, Mechanicsburg and Camp Hill.

Additional rainfall of three quarters of an inch to one inch is
likely late this morning into early this afternoon across the
flood advisory area.


--------------------
Blue Ridge Bouncer

Cascade, MD
Elevation: 1625'


90 Degree Days in 2017: 0
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