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Pittsburgh PA spring 2017


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Flash Flood Warning

Flash Flood Warning
PAC003-051-125-129-290815-
/O.NEW.KPBZ.FF.W.0073.170729T0314Z-170729T0815Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Pittsburgh PA
1114 PM EDT FRI JUL 28 2017

The National Weather Service in Pittsburgh has issued a

* Flash Flood Warning for...
  Southeastern Washington County in southwestern Pennsylvania...
  Southeastern Allegheny County in southwestern Pennsylvania...
  Southwestern Westmoreland County in southwestern Pennsylvania...
  Northwestern Fayette County in southwestern Pennsylvania...

* Until 415 AM EDT.

* At 1113 PM EDT, radar indicated heavy rain in the warned area.

  FLASH FLOODING...     Expected.

  ESTIMATED RAINFALL... Up to 2 inches.

  ADDITIONAL RAINFALL...Up to 2 inches.

* Some locations that may experience flooding include...
  Monroeville...                    Greensburg...
  McKeesport...                     Jeannette...
  Gastonville...                    Murrysville...
  South Park Township...            Jefferson Hills...
  North Versailles...               White Oak...
  Monessen...                       Clairton...

This includes the following highways...
  Interstate 70 in Pennsylvania between mile markers 28 and 57.

  Pennsylvania Turnpike between mile markers 59 and 75.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don`t drown. Most flood fatalities occur in vehicles.

Be especially cautious at night, when it is harder to recognize the
dangers of flooding.

Please report flooding by calling 412-262-1988, posting to
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH.

&&

LAT...LON 3997 7971 3994 7994 3995 7996 3995 8000
      3996 8001 3998 8000 3998 8005 4000 8004
      4001 8006 3999 8008 3999 8011 4001 8018
      4000 8019 4001 8023 4000 8027 4031 7993
      4042 7970 4032 7956

$$

Fries


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29 minutes ago, CoraopolisWx said:

Yeah, not something we see very much.

I was thinking bust earlier this evening, but then that deform band really blew up around 8:30.

Just looking at this storm on radar one would think it was a Winter Storm... Intense rainfall right now, we finally get in on a good deform band... but its July lol.

Even NWS was making comparisons to winter storm look in a previous discussion:

SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
Interesting developments during this period that are more often
seen during the winter season. As the upper low drops across
western PA tonight and toward the Delmarva area Saturday, the
system takes on a more neutral tilt with time. Very strong
U-component anomalies, around 4 standard deviations on the
NAEFS, will promote moist onshore flow into the ridges. There is
also a clear trowal signal over PA late tonight and into
Saturday in the 700-500 mb layer. This all points to an
unusually strong summertime synoptic setup that could result in
excessive rainfall over parts of the area, particularly the
ridges. Have continued with the highest PoPs in this region,
tapering off to the northwest. The system will only slowly pull
away with time, with a few showers lingering into Saturday night
southeast of Pittsburgh, before finally ending overnight.
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7 minutes ago, blackngoldrules said:

Flooding all over the place now. Glad I made it home. Road closures everywhere.

Not surprising, I am at a pretty high elevation relatively speaking, so no concern for flooding in my immediate area and very thankful for that, but even my backyard is starting to pool water.

Check out the radar returns:

 

Capture.JPG

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57 minutes ago, RitualOfTheTrout said:

Just looking at this storm on radar one would think it was a Winter Storm... Intense rainfall right now, we finally get in on a good deform band... but its July lol.

Even NWS was making comparisons to winter storm look in a previous discussion:



 

Some guy on twitter was showing the position of the 850mb low over W. MD/E. WV

That's usually our sweetspot for deform bands.

Could've used this setup in Jan 2016, and March 2017. smh

55 minutes ago, blackngoldrules said:

Flooding all over the place now. Glad I made it home. Road closures everywhere.

Yeah, coming home I took a chance going down 88 to 51 around 9pm.

Luckily I got through before they closed that intersection.

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Flash Flood Warning

Flash Flood Warning
PAC003-291030-
/O.EXT.KPBZ.FF.W.0066.000000T0000Z-170729T1030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Pittsburgh PA
107 AM EDT SAT JUL 29 2017

The National Weather Service in Pittsburgh has extended the

* Flash Flood Warning for...
  Southeastern Allegheny County in southwestern Pennsylvania...

* Until 630 AM EDT.

* At 106 AM EDT, law enforcement officials reported flash flooding
  in the warned area with multiple road closures and water rescues
  ongoing.

  FLASH FLOODING...     Occurring.

  ESTIMATED RAINFALL... Up to 3 inches.

  ADDITIONAL RAINFALL...Up to 1 inch.

* Some locations that may experience flooding include...
  Pittsburgh...                     Penn Hills...
  Mount Lebanon...                  Bethel Park...
  Monroeville...                    McKeesport...
  Gastonville...                    Plum...
  West Mifflin...                   Baldwin...
  Upper St. Clair...                Murrysville...

This includes the following highways...
  Pennsylvania Turnpike between mile markers 53 and 58.

  Interstate 79 in Pennsylvania between mile markers 22 and 24.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don`t drown. Most flood fatalities occur in vehicles.

Be especially cautious at night, when it is harder to recognize the
dangers of flooding.

Runoff from heavy rainfall will flood small streams, poor-drainage
areas and low-lying spots.

Please report flooding by calling 412-262-1988, posting to
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH.

&&

LAT...LON 4039 7975 4039 7977 4036 7977 4027 7999
      4033 8017 4053 7970 4043 7970

$$

Fries
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11 hours ago, CoraopolisWx said:

Some guy on twitter was showing the position of the 850mb low over W. MD/E. WV

That's usually our sweetspot for deform bands.

Could've used this setup in Jan 2016, and March 2017. smh

Yeah, coming home I took a chance going down 88 to 51 around 9pm.

Luckily I got through before they closed that intersection.

Yea, we had major flooding up here yesterday afternoon-this summer has been a constant moisture flow-Im sure the pattern will change and it will be bone dry come December....lol

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2 hours ago, ChalkHillSnowNut said:

Yea, we had major flooding up here yesterday afternoon-this summer has been a constant moisture flow-Im sure the pattern will change and it will be bone dry come December....lol

Unfortunately, all we can do anymore is expect the worst, and hope for something decent. 

Mabey this year you'll get some better upslope, and really cash in on your elevation. 

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mcd1442.gif

 Mesoscale Discussion 1442
   NWS Storm Prediction Center Norman OK
   1038 AM CDT Fri Aug 04 2017

   Areas affected...Much of the upper Ohio Valley

   Concerning...Severe potential...Watch possible 

   Valid 041538Z - 041745Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Severe hail/wind risk with increasing thunderstorm
   development may remain somewhat localized and/or sparse in coverage
   through early to mid afternoon.  However, potential does exist for a
   slow increase in coverage and organization which could be
   accompanied by a more substantive risk for damaging wind gusts later
   this afternoon.  Trends will continue to be monitored for the
   possibility of a watch.

   DISCUSSION...Weak to moderate pre-cold frontal destabilization is
   now underway across much of the upper Ohio Valley, primarily as
   insolation contributes to warming of a seasonably moist boundary
   layer.  Latest objective analysis suggests that inhibition is
   already becoming increasingly negligible, particularly within a
   corridor ahead of the front, from parts of north central Kentucky
   through the Lake Erie area.  Aided by large-scale ascent ahead of a
   significant short wave trough now pivoting eastward toward the lower
   Great Lakes/upper Ohio Valley region, a general increase in
   thunderstorm activity appears likely through 17-20Z.

   Further daytime heating may yield CAPE as high as 1500-2000 J/kg,
   supportive of vigorous updrafts.  However, warm sector southwesterly
   deep layer mean flow, even with some strengthening, appears likely
   to remain on the order of 30-35 kt.  And models indicate that the
   mid-level cold core of the approaching system will lag to the west. 
   Still, weak cooling aloft may be enough to support some risk for
   marginally severe hail in initial stronger pulsing activity. 
   Vertical shear and instability may become marginally sufficient to
   support a gradual increase in convective organization, which may
   eventually be accompanied by an increasing risk for potentially
   damaging wind gusts.  This probably will take some time through,
   with any severe hail/wind risk expected to initially remain fairly
   sparse in coverage.

   ..Kerr/Goss.. 08/04/2017
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WATCH COUNTY NOTIFICATION FOR WATCH 439
NATIONAL WEATHER SERVICE PITTSBURGH PA
125 PM EDT FRI AUG 4 2017

MDC023-OHC013-019-029-031-059-067-081-111-119-121-157-PAC003-005-
007-019-031-051-053-059-063-065-073-085-121-125-129-WVC009-029-
049-051-061-069-077-103-050100-
/O.NEW.KPBZ.SV.A.0439.170804T1725Z-170805T0100Z/

THE NATIONAL WEATHER SERVICE HAS ISSUED SEVERE THUNDERSTORM WATCH
439 IN EFFECT UNTIL 9 PM EDT THIS EVENING FOR THE FOLLOWING AREAS

IN MARYLAND THIS WATCH INCLUDES 1 COUNTY

IN WESTERN MARYLAND

GARRETT

IN OHIO THIS WATCH INCLUDES 11 COUNTIES

IN EAST CENTRAL OHIO

BELMONT               CARROLL               COLUMBIANA
COSHOCTON             GUERNSEY              HARRISON
JEFFERSON             MONROE                MUSKINGUM
NOBLE                 TUSCARAWAS

IN PENNSYLVANIA THIS WATCH INCLUDES 15 COUNTIES

IN NORTHWEST PENNSYLVANIA

FOREST                MERCER                VENANGO

IN SOUTHWEST PENNSYLVANIA

ALLEGHENY             FAYETTE               GREENE
WASHINGTON            WESTMORELAND

IN WEST CENTRAL PENNSYLVANIA

ARMSTRONG             BUTLER                CLARION
INDIANA               JEFFERSON

IN WESTERN PENNSYLVANIA

BEAVER                LAWRENCE

IN WEST VIRGINIA THIS WATCH INCLUDES 8 COUNTIES

IN NORTHEAST WEST VIRGINIA

PRESTON

IN NORTHERN WEST VIRGINIA

MARION                MONONGALIA            WETZEL

IN NORTHERN PANHANDLE OF WEST VIRGINIA

BROOKE                HANCOCK               MARSHALL
OHIO

THIS INCLUDES THE CITIES OF ALIQUIPPA, AMBRIDGE, BEAVER FALLS,
BROOKVILLE, BUTLER, CADIZ, CALDWELL, CAMBRIDGE, CANONSBURG,
CARROLLTON, CLARION, COLUMBIANA, CONNELLSVILLE, COSHOCTON, DOVER,
EAST LIVERPOOL, ELLWOOD CITY, FAIRMONT, FOLLANSBEE, FORD CITY,
FRANKLIN, GRANTSVILLE, GREENSBURG, GROVE CITY, HERMITAGE,
INDIANA, KINGWOOD, KITTANNING, LATROBE, MARTINS FERRY, MASONTOWN,
MONACA, MORGANTOWN, MOUNDSVILLE, MOUNTAIN LAKE PARK, MURRYSVILLE,
NEW CASTLE, NEW KENSINGTON, NEW MARTINSVILLE, NEW PHILADELPHIA,
OAKLAND MD, OIL CITY, PITTSBURGH METRO AREA, PUNXSUTAWNEY, SALEM,
SHARON, ST. CLAIRSVILLE, STEUBENVILLE, TERRA ALTA, TIONESTA,
UNIONTOWN, WASHINGTON, WAYNESBURG, WEIRTON, WELLSBURG, WHEELING,
WOODSFIELD, AND ZANESVILLE.

$$
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Severe Thunderstorm Warning

Severe Thunderstorm Warning
OHC029-PAC003-007-019-125-WVC009-029-041845-
/O.NEW.KPBZ.SV.W.0152.170804T1801Z-170804T1845Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Pittsburgh PA
201 PM EDT FRI AUG 4 2017

The National Weather Service in Pittsburgh has issued a

* Severe Thunderstorm Warning for...
  Southeastern Columbiana County in east central Ohio...
  Western Washington County in southwestern Pennsylvania...
  Beaver County in western Pennsylvania...
  Southwestern Butler County in west central Pennsylvania...
  Western Allegheny County in southwestern Pennsylvania...
  Northeastern Brooke County in northern West Virginia...
  Eastern Hancock County in northern West Virginia...

* Until 245 PM EDT.

* At 201 PM EDT, severe thunderstorms were located along a line
  extending from Follansbee to near Avella to 6 miles south of East
  Washington, moving north at 45 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar.

  IMPACT...Damage to trees and power lines.

* Locations impacted include...
  Pittsburgh...                     Mount Lebanon...
  Bethel Park...                    Ross Township...
  McCandless Township...            Moon Township...
  McMurray...                       Weirton...
  Washington...                     Franklin Park...
  East Liverpool...                 Aliquippa...

This includes the following highways...

  Interstate 70 in Pennsylvania between mile markers 12 and 27.

  Interstate 79 in Pennsylvania between mile markers 22 and 47.

  Interstate 279 in Pennsylvania between mile markers 1 and 13.

  Interstate 376 in Pennsylvania between mile markers 33 and 73.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to an interior room on the lowest floor of a building.

Please report severe weather by calling 412-262-1988, posting to
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH.

&&

LAT...LON 4068 8014 4051 7990 4000 8016 4000 8020
      4020 8040 4033 8060 4056 8058 4064 8053
      4064 8052 4079 8049
TIME...MOT...LOC 1801Z 201DEG 38KT 4035 8059 4025 8038 4008 8021

HAIL...<.75IN
WIND...60MPH

$$

Kramar


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mcd1443.gif

 Mesoscale Discussion 1443
   NWS Storm Prediction Center Norman OK
   0246 PM CDT Fri Aug 04 2017

   Areas affected...Lower Great Lakes/Allegheny Plateau region

   Concerning...Severe Thunderstorm Watch 439...

   Valid 041946Z - 042145Z

   The severe weather threat for Severe Thunderstorm Watch 439
   continues.

   SUMMARY...Small to, perhaps, marginally severe hail and
   localized/spotty damaging wind gusts will remain possible near
   thunderstorm activity overspreading the region through early
   evening.

   DISCUSSION...Potential for substantive further organization of
   ongoing pre-cold frontal convective development into the 21-23Z time
   frame is appearing increasing unlikely, as objective analysis
   indicates that deep layer vertical shear remains weak across much of
   the warm sector south and east of Lakes Erie and Ontario.  However,
   mean lower/mid tropospheric wind fields are strengthening to 30-40
   kt across western Pennsylvania and much of New York state.  And this
   could continue to augment severe weather potential with thunderstorm
   activity developing northeastward/eastward across the region through
   the remainder of the afternoon, primarily associated with localized
   enhanced downward transfer of momentum within areas of heavier
   precipitation loading.

   ..Kerr.. 08/04/2017
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  • 2 weeks later...
   URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 457
   NWS Storm Prediction Center Norman OK
   245 PM EDT Sat Aug 19 2017

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     East Central Ohio
     Western and Central Pennsylvania
     Northern West Virginia Panhandle

   * Effective this Saturday afternoon and evening from 245 PM until
     900 PM EDT.

   * Primary threats include...
     Scattered damaging wind gusts to 65 mph possible
     Scattered large hail events to 1.5 inches in diameter possible

   SUMMARY...Storms developing over eastern Ohio into northwest
   Pennsylvania are expected to move eastward with potential to produce
   damaging wind gusts and occasional large hail.  The activity will
   continue into parts of central Pennsylvania into the early evening
   hours before weakening after sunset.

   The severe thunderstorm watch area is approximately along and 50
   statute miles north and south of a line from 20 miles west northwest
   of Zanesville OH to 45 miles east of State College PA. For a
   complete depiction of the watch see the associated watch outline
   update (WOUS64 KWNS WOU7).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   1.5 inches. Extreme turbulence and surface wind gusts to 55 knots. A
   few cumulonimbi with maximum tops to 450. Mean storm motion vector
   27030.

   ...Weiss
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7 minutes ago, meatwad said:

   URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 457
   NWS Storm Prediction Center Norman OK
   245 PM EDT Sat Aug 19 2017

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     East Central Ohio
     Western and Central Pennsylvania
     Northern West Virginia Panhandle

   * Effective this Saturday afternoon and evening from 245 PM until
     900 PM EDT.

   * Primary threats include...
     Scattered damaging wind gusts to 65 mph possible
     Scattered large hail events to 1.5 inches in diameter possible

   SUMMARY...Storms developing over eastern Ohio into northwest
   Pennsylvania are expected to move eastward with potential to produce
   damaging wind gusts and occasional large hail.  The activity will
   continue into parts of central Pennsylvania into the early evening
   hours before weakening after sunset.

   The severe thunderstorm watch area is approximately along and 50
   statute miles north and south of a line from 20 miles west northwest
   of Zanesville OH to 45 miles east of State College PA. For a
   complete depiction of the watch see the associated watch outline
   update (WOUS64 KWNS WOU7).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   1.5 inches. Extreme turbulence and surface wind gusts to 55 knots. A
   few cumulonimbi with maximum tops to 450. Mean storm motion vector
   27030.

   ...Weiss

CODNEXLAB-GOES16-Visible-18:47Z-20170819

Looks impressive on GOES-16

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Severe Thunderstorm Warning

Severe Weather Statement
National Weather Service Pittsburgh PA
443 PM EDT SAT AUG 19 2017

PAC003-125-192100-
/O.CON.KPBZ.SV.W.0182.000000T0000Z-170819T2100Z/
Washington PA-Allegheny PA-
443 PM EDT SAT AUG 19 2017

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 500 PM EDT
FOR CENTRAL WASHINGTON AND SOUTHERN ALLEGHENY COUNTIES...

At 442 PM EDT, a severe thunderstorm was located over Cecil-Bishop,
or near Canonsburg, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar.

IMPACT...Expect damage to trees and power lines, resulting in some
         power outages.

Locations impacted include...
Pittsburgh...                     Mount Lebanon...
Bethel Park...                    McMurray...
McKeesport...                     Canonsburg...
Gastonville...                    West Mifflin...
Baldwin...                        Upper St. Clair...
Scott Township...                 Whitehall...

This includes  Interstate 79 in Pennsylvania between mile markers 22
and 30.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to an interior room on the lowest floor of a building.

Please report severe weather by calling 412-262-1988, posting to
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH.

&&

LAT...LON 4028 8035 4036 8031 4043 8020 4040 7984
      4014 7993
TIME...MOT...LOC 2042Z 283DEG 24KT 4033 8019

HAIL...<.75IN
WIND...60MPH

$$

Fries

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That was about as isolated as a downpour can get. Just about as heavy as the severe storm on Saturday. Would be kind of cool to get that during part of the eclipse, to make it that much darker.

 

I'm just hoping there aren't any clouds around when it happens today. I'm actually off work today, so I might take a ride down to the Science Center in a little while to check it out. I can't find glasses anywhere now so that would be my only option at this point. Getting the downpour here right now, btw.

 

Sent from my SM-G920P using Tapatalk

 

 

 

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Interesting set up today. Could really get rocking by 4 pm

SPC AC 221228

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0728 AM CDT Tue Aug 22 2017

Valid 221300Z - 231200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS MAINLY THIS
AFTERNOON FROM EASTERN OH AND PA ACROSS NY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SURROUNDING THE
ENHANCED RISK AREA...FROM KY TO WESTERN NEW ENGLAND...

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM TN TO OK
AND THE TX PANHANDLE...

...SUMMARY...
Severe thunderstorms with damaging winds, and possibly a couple of
tornadoes, are expected this afternoon from the upper Ohio Valley to
Pennsylvania and New York. Thunderstorms with isolated
strong/damaging gusts will also be possible farther southwest into
parts of the southern Plains.

...NY/PA to the southern Plains through late evening...
A pronounced midlevel trough over the upper Great Lakes will
continue to amplify while approaching Quebec tonight. Associated
surface cyclogenesis preceding the midlevel trough will drive a
surface cold front southeastward across the lower Great Lakes and OH
Valley by tonight. In addition, the remnants of a subtropical speed
max, enhanced by overnight convection across IL/MO, will accelerate
east-northeastward over the OH Valley/PA/NY in advance of the
primary midlevel trough, and in phase with the diurnal heating
cycle.

It appears that the primary focus for thunderstorm development today
will a pre-frontal or the remnant outflow/differential heating zone
on the leading edge of the ongoing convection from IN to MO.
Convection will likely strengthen/redevelop by midday or early
afternoon across OH and western NY, and storms will subsequently
spread eastward across PA/NY through the afternoon. Midlevel flow
and effective bulk shear will likewise strengthen into the 40-50 kt
range from OH to PA/NY this afternoon, as surface heating results in
steepening low-level lapse rates and MLCAPE near 1500 J/kg. The
primary convective evolution should a mixed mode transitioning to
line segments, with the potential for downward momentum transfer and
swaths of damaging winds with the more intense bowing segments.
Additionally, there will be a coincident increase in low-level
shear/hodograph curvature across PA/NY during the afternoon in
response to the cyclogenesis to the north. Given the relatively
moist environment, semi-discrete storms could pose a tornado threat,
along with embedded QLCS mesovortices. The large hail threat should
remain marginal as a result of modest midlevel lapse rates.

Deep-layer flow and shear will weaken with southward extent from KY
into TN, and the weak-shear environment will extend westward along
the surface cold front in the vicinity of I-40 in OK/TX this
afternoon. Loosely organized multicell clusters are expected along
the front from TN across AR into OK/TX Panhandle, where isolated
downbursts will be the main threat this afternoon/evening.

..Thompson/Smith.. 08/22/2017



Sent from my iPhone using Tapatalk

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[imgmcd1547.gif

Mesoscale Discussion 1547
   NWS Storm Prediction Center Norman OK
   1054 AM CDT Tue Aug 22 2017

   Areas affected...Western PA...Southeast OH...Western WV...Northern
   KY...

   Concerning...Severe potential...Severe Thunderstorm Watch likely 

   Valid 221554Z - 221700Z

   Probability of Watch Issuance...80 percent

   SUMMARY...Severe thunderstorm watch will likely be issued by 17z
   across portions of the Ohio Valley.

   DISCUSSION...Pre-frontal boundary-layer cumulus field is
   expanding/deepening across the OH Valley as surface temperatures
   warm into the lower 80s. While mid-level lapse rates are poor due to
   high PW air mass, surface-3km lapse rates have steepened enough for
   surface parcels to reach their LFC. Lightning is beginning to
   increase with maturing convection from the northwest portions of PA,
   southwest along the OH River into southern IN. This activity should
   gradually increase in areal coverage within a sheared environment
   favorable for organized line segments and clusters. A considerable
   amount of convection is expected along this corridor within a few
   hours and locally damaging winds can be expected with these storms.
   Severe thunderstorm watch is warranted for this evolving threat.

   ..Darrow/Grams.. 08/22/2017
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URGENT - IMMEDIATE BROADCAST REQUESTED
   Severe Thunderstorm Watch Number 462
   NWS Storm Prediction Center Norman OK
   1240 PM EDT Tue Aug 22 2017

   The NWS Storm Prediction Center has issued a

   * Severe Thunderstorm Watch for portions of 
     Far southern Indiana
     Central and northern Kentucky
     Far western Maryland Panhandle
     Southern and eastern Ohio
     Western and central Pennsylvania
     Northern and western West Virginia

   * Effective this Tuesday afternoon and evening from 1240 PM until
     900 PM EDT.

   * Primary threats include...
     Scattered damaging wind gusts to 70 mph likely
     A tornado or two possible

   SUMMARY...Scattered damaging winds appear likely as numerous
   clusters and lines of storms intensify and move east this afternoon.

   The severe thunderstorm watch area is approximately along and 105
   statute miles east and west of a line from 15 miles northeast of
   Dubois PA to 60 miles south southeast of Louisville KY. For a
   complete depiction of the watch see the associated watch outline
   update (WOUS64 KWNS WOU2).

   PRECAUTIONARY/PREPAREDNESS ACTIONS...

   REMEMBER...A Severe Thunderstorm Watch means conditions are
   favorable for severe thunderstorms in and close to the watch area.
   Persons in these areas should be on the lookout for threatening
   weather conditions and listen for later statements and possible
   warnings. Severe thunderstorms can and occasionally do produce
   tornadoes.

   &&

   OTHER WATCH INFORMATION...CONTINUE...WW 461...

   AVIATION...A few severe thunderstorms with hail surface and aloft to
   1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
   few cumulonimbi with maximum tops to 500. Mean storm motion vector
   26025.

   ...Grams
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BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Pittsburgh PA
120 PM EDT TUE AUG 22 2017

The National Weather Service in Pittsburgh has issued a

* Severe Thunderstorm Warning for...
  Northwestern Washington County in southwestern Pennsylvania...
  Central Allegheny County in southwestern Pennsylvania...

* Until 200 PM EDT.

* At 119 PM EDT, a severe thunderstorm was located near Avella,
  moving east at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar.

  IMPACT...Damage to trees and power lines.

* Locations impacted include...
  Pittsburgh...                     Penn Hills...
  Mount Lebanon...                  Bethel Park...
  Ross Township...                  McMurray...
  McKeesport...                     Canonsburg...
  Avella...                         Shaler Township...
  West Mifflin...                   North Side Pittsburgh...

This includes the following highways...

  Interstate 79 in Pennsylvania between mile markers 22 and 35.

  Interstate 279 in Pennsylvania between mile markers 1 and 7.

  Interstate 376 in Pennsylvania between mile markers 57 and 77.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to an interior room on the lowest floor of a building.

Please report severe weather by calling 412-262-1988, posting to
the NWS Pittsburgh Facebook page, or using Twitter @NWSPITTSBURGH.
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