Login to AccuWeather.com Premium Login to AccuWeather.com Professional Login to AccuWeather.com RadarPlus AccuWeather.com
We have updated our Privacy Policy and our Cookie Policy effective May 25, 2018. Please review them.
X

Welcome Guest ( Log In | Register )

32 Pages V   1 2 3 > »   
Reply to this topicStart new topic
> May 12-23 MidAtl/NE Stationary Fronts - Rain | Severe | Flooding Potential, Extended Period Forecasts and Observations
PlanetMaster
post May 11 2018, 05:46 AM
Post #1




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





A stationary front in or just south of the area with several disturbances riding along, one Saturday and one Sunday. The chance of rain for the weekend with possibility of thunderstorms and heavy rain as a result of daytime heating is possible as well. There may even be another low on Monday. This is the beginning of what looks like a very unsettled and wet period that could stretch right into the end of the month and could include a possible tropical system riding up the coast.

With this setup, East to West, warm humid air coming North training is a real possibility and heavy amounts of rain possible locally. Can't rule out strong to severe thunderstorms in southern areas as well. Looks to be mostly SNE and Northern MA for the heaviest precip at this time.

EDIT: Have extended the period on the thread as it is going to be active right through this week and beyond.

GFS


This post has been edited by PlanetMaster: May 22 2018, 08:22 AM


--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
PlanetMaster
post May 11 2018, 05:49 AM
Post #2




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





NAM has over 2 inches through CPA towards the coast.





I always thought my first thread would be white but this weekend looks very wet. As stated above could be allot more rain in the next couple weeks as we are in the front stall zone for a extended stretch on the northern edge of the "ring of fire" with a weak SE ridge.

This post has been edited by PlanetMaster: May 11 2018, 06:09 AM


--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
geeter1
post May 11 2018, 07:57 AM
Post #3




Rank: Tornado
**

Group: Member
Posts: 365
Joined: 7-November 09
From: Orefield, PA
Member No.: 19,681







We can use the rain. It's already pretty dry in these parts....
Go to the top of the page
 
+Quote Post
phillyfan
post May 11 2018, 12:56 PM
Post #4




Rank: F5 Superstorm
***

Group: Member
Posts: 9,997
Joined: 13-January 08
From: Wernersville, PA (Berks Co.)
Member No.: 12,448





Is this for the severe weather tomorrow as well. Slight Risk has been upgraded to enhanced now:

Attached Image


--------------------
Severe Weather 2018

Tornado Watch: 5/12
Severe T-Storm Watch: 5/15
Severe T-Storm Warning: 5/15, 6/18, 7/27
Flash Flood Watch: 5/15-16, 5/27, 7/21-22, 7/23-26, 7/27, 8/2-4, 8/11-12
Flood Watch: 5/17-19
Flood Warning: 6/10-11, 8/4
Flash Flood Warning: 7/4, 7/22-23, 7/27, 8/3-4, 8/11
Go to the top of the page
 
+Quote Post
phils1
post May 11 2018, 01:25 PM
Post #5




Rank: Tornado
**

Group: Member
Posts: 205
Joined: 23-August 11
Member No.: 25,921





12Z NAM-Nest updraft helicity swath at 8pm on Saturday showing enhanced values across PA, NJ...isolated tornadoes possible from northern MD to southern PA, NJ as low-level wind shear increases late tomorrow near a developing surface low:

https://www.vencoreweather.com/blog/2018/5/...rstorm-activity
Attached thumbnail(s)
Attached Image
 
Go to the top of the page
 
+Quote Post
PlanetMaster
post May 11 2018, 02:50 PM
Post #6




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





QUOTE(phillyfan @ May 11 2018, 01:56 PM) *
Is this for the severe weather tomorrow as well. Slight Risk has been upgraded to enhanced now:

Attached Image

Absolutely, part of the same system. I will update the title to include severe possibility. Southern half of PA looking primed for strong storms at least and torrential downpours. Although NWS hasn't mentioned the locally heavy rain, wouldn't be surprised to see 2, 3, even 4+ inches as these storms will train over the same areas for hours.

Convective outlook Saturday GFS
Attached Image


Attached Image



QUOTE
National Weather Service State College PA
246 PM EDT Fri May 11 2018

SHORT TERM /MIDNIGHT THROUGH 6 PM SATURDAY/...
WAA really gets going overnight and by midnight almost everyone
is wet as 8H jet becomes W45-50kts. This will ride right over
the languishing front and generate rain, and some instability is
possible across the W and esp N, so will keep in the mention of
TS. The focal point for the overrunning rain will be just to
the north of the front, mainly in nrn PA. QPF runs close to an
inch there tonight. The ground is wet, but that should not be
enough to make any flooding. The srn tier dries out after a
brief period of showers early tonight. But, the front waggles
southward again on Sat, and additional rain is expected to push
back S and get them wet by the end of the day. Instability along
the srn edge of the morning rain could pop storms as early as
late morning. Latest SWODY2 for Sat keeps most of the CWA in
SLGT risk for svr. WNW 40-50KT mid level flow will combine with
peak heating and perhaps an EML as mentioned by SPC to make
stronger storms in the afternoon and early evening. Temps in the
mid-80s are possible in the SC counties with nearly full sun on
Sat and CAPEs would be AOA 1500 J/kg. LCLs are initially pretty
low, and presence of the warm frontal boundary could make it
interesting. On the bad side for storms, there is quite a bit of
a cap to poke through.
While this does not seem like a true NW-
flow severe set up, the hodograph is curved a bit, and storm
motion will be slightly S of E.


This post has been edited by PlanetMaster: May 11 2018, 03:08 PM


--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
ClicheVortex2014
post May 11 2018, 03:22 PM
Post #7




Rank: F5 Superstorm
***

Group: Member
Posts: 22,676
Joined: 21-April 14
From: Dayton, Ohio
Member No.: 29,453





Was wondering how long it'd take you guys to open a thread laugh.gif

Looks like an MCS day. 12km NAM is kinda showing it, 3km not at all really, but RPM and experimental HRRR are showing this pretty well. A word of caution is don't get set on any exact path until 6-10 hours before impact. These events are notoriously hard to predict.






--------------------
Meteorology undergrad at Ohio University (weather on campus)

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
Go to the top of the page
 
+Quote Post
PlanetMaster
post May 11 2018, 03:30 PM
Post #8




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





QUOTE(ClicheVortex2014 @ May 11 2018, 04:22 PM) *
Was wondering how long it'd take you guys to open a thread laugh.gif

Looks like an MCS day. 12km NAM is kinda showing it, 3km not at all really, but RPM and experimental HRRR are showing this pretty well. A word of caution is don't get set on any exact path until 6-10 hours before impact. These events are notoriously hard to predict.






Was going to open it last night but wanted to see how things looked this morning and was surprised to see how much better the overall situation progressed. Agree whole heartedly about path NAM is juiced and a touch further North then GFS so anywhere in between be on the lookout. Going to be interesting across PA/ NNJ and NYC/LI



--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
ClicheVortex2014
post May 11 2018, 03:39 PM
Post #9




Rank: F5 Superstorm
***

Group: Member
Posts: 22,676
Joined: 21-April 14
From: Dayton, Ohio
Member No.: 29,453





Having trouble quoting on this thread for some reason but yeah this is looking like a classic NW flow severe event. First one of the year for this latitude, although there has been some ridge topping MCSs over the past 2 days in the Plains.

This is one of those things where Id be nervous if I was in the bullseye at this point, just as Id be nervous if I was in the bullseye for snow 72+ hours out.

This post has been edited by ClicheVortex2014: May 11 2018, 03:40 PM


--------------------
Meteorology undergrad at Ohio University (weather on campus)

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
Go to the top of the page
 
+Quote Post
PlanetMaster
post May 11 2018, 03:45 PM
Post #10




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





QUOTE(ClicheVortex2014 @ May 11 2018, 04:39 PM) *
Having trouble quoting on this thread for some reason but yeah this is looking like a classic NW flow severe event. First one of the year for this latitude, although there has been some ridge topping MCSs over the past 2 days in the Plains.

This is one of those things where Id be nervous if I was in the bullseye at this point, just as Id be nervous if I was in the bullseye for snow 72+ hours out.

That is exactly what got me interested the NW Jet which is usually the only way to get severe weather in my backyard this early in the season. Either way looks like a soaking tomorrow and we need the rain.

Expect to see local amounts upwards of 3 or 4+ inches locally in those strong storms, a good soaking for many

Attached Image


This post has been edited by PlanetMaster: May 11 2018, 04:00 PM


--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
Miller A
post May 11 2018, 04:40 PM
Post #11




Rank: F5 Superstorm
***

Group: Member
Posts: 3,548
Joined: 5-December 08
From: Sussex, NJ
Member No.: 16,359





bizarre setup for this time of year, no?


Holly AFD

This "coast-to-coast"
frontal boundary spans westward across the entire CONUS.


The aforementioned boundary should start to lift back northward as a
warm front in response to strengthening/backing flow in the low-
levels ahead of a shortwave trough. However at the surface, the warm
front will likely struggle to make significant northward progress
owing to a cold-air damming (CAD) setup. This hybrid CAD wedge will
be reinforced late tonight via evaporative cooling processes (i.e.,
in-situ CAD) when precip arrives and falls into the very dry airmass
in place north of the front.


--------------------
TOTAL 2017-18: 52.35"
TOTAL 2016-17: 52.75"
TOTAL 2015-16: 17.90"
TOTAL 2014-15: 51.10"
TOTAL 2013-14: 62.10"
TOTAL 2012-13: 46.00"
TOTAL 2011-12: 18.05"

TOTAL 2010-11: 52.40"
TOTAL 2009-10: 64.00"


Alt 248 = degrees symbol
Go to the top of the page
 
+Quote Post
PlanetMaster
post May 11 2018, 05:15 PM
Post #12




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





QUOTE(Miller A @ May 11 2018, 05:40 PM) *
bizarre setup for this time of year, no?
Holly AFD

This "coast-to-coast"
frontal boundary spans westward across the entire CONUS.


The aforementioned boundary should start to lift back northward as a
warm front in response to strengthening/backing flow in the low-
levels ahead of a shortwave trough. However at the surface, the warm
front will likely struggle to make significant northward progress
owing to a cold-air damming (CAD) setup. This hybrid CAD wedge will
be reinforced late tonight via evaporative cooling processes (i.e.,
in-situ CAD) when precip arrives and falls into the very dry airmass
in place north of the front.


Old man winter stubborn as mule not wanting to give ground, basically an over running event which we would typically see in the Winter but with Summertime heat and humidity in the mix. Add a spark running along the front, a recipe for rapid lift and convection resulting in severe storms and torrential downpours. Not something we see on the reg thats for sure and thats why could be some very dangerous weather. I am surprised at the NWS not mentioning the potential for flash flooding as I have seen events like this produce copious amounts of rain, especially with the training I expect. Whenever a front lines up East to West with such a great difference in air masses across the boundary that is always a concern. I am sure they will update their AFD's with the mention of locally high amounts as they are only forecasting 1/2 to an inch and that clearly is way off the mark IMO. I mean I can see the potential clear as day just from the guidance so far.

Latest HRRR even more North with the overall shield and just buckets of moisture falling into that 'dry' air. NEPA/LHV/NNJ/NYC/LI look to get whomped! I emptied the big bucket out back, going to let it ride till end of month. March and April put 2 feet of liquid in it, expect another 6-10" before this month is out if the current wet guidance holds. Just the forecast anyone would want to see in Spring

Attached Image




Look at the division from dews in the mid/upper 60's & temps in the 80's to dews in the 40's & temps in the 50's. turn on the faucet just North of the front, someone will see 3+" easy I would hazard to guess.

Attached Image


This post has been edited by PlanetMaster: May 11 2018, 05:39 PM


--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
ClicheVortex2014
post May 11 2018, 06:01 PM
Post #13




Rank: F5 Superstorm
***

Group: Member
Posts: 22,676
Joined: 21-April 14
From: Dayton, Ohio
Member No.: 29,453





Latest experimental HRRR lost the MCS.



At night, though, it has a bunch of cells. Discrete activity in Ohio and MCS to the east.


This post has been edited by ClicheVortex2014: May 11 2018, 06:07 PM


--------------------
Meteorology undergrad at Ohio University (weather on campus)

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
Go to the top of the page
 
+Quote Post
PlanetMaster
post May 11 2018, 06:14 PM
Post #14




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





QUOTE(ClicheVortex2014 @ May 11 2018, 07:01 PM) *
Latest experimental HRRR lost the MCS.



At night, though, it has a bunch of cells. Discrete activity in Ohio and MCS to the east.

Will be interesting to see where the convergence zone starts overnight into the morning and how it progresses. The warm front ahead of our disturbance on Saturday wont make much headway North but will certainly throw a ton of moisture over the top. Will be watching when it stalls and then slowly comes south again. Areas in and around that zone will be pummeled with rain but in your opinion where would the severe storms most likely setup within the zone, just south, or just North of that zone? Or all of the above? tongue.gif

This post has been edited by PlanetMaster: May 11 2018, 06:15 PM


--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
ClicheVortex2014
post May 11 2018, 06:55 PM
Post #15




Rank: F5 Superstorm
***

Group: Member
Posts: 22,676
Joined: 21-April 14
From: Dayton, Ohio
Member No.: 29,453





QUOTE(PlanetMaster @ May 11 2018, 07:14 PM) *
Will be interesting to see where the convergence zone starts overnight into the morning and how it progresses. The warm front ahead of our disturbance on Saturday wont make much headway North but will certainly throw a ton of moisture over the top. Will be watching when it stalls and then slowly comes south again. Areas in and around that zone will be pummeled with rain but in your opinion where would the severe storms most likely setup within the zone, just south, or just North of that zone? Or all of the above? tongue.gif

Yeah, there is really strong convergence along that front. We're seeing that now in Michigan, and later tonight more storms will pop in Iowa which will move east, nearly parallel to the stationary front.

I'm thinking this convection will be the trigger for the severe weather event tomorrow, as is often the case for summer MCS events. Usually it becomes elevated with a small hail threat before it becomes surface-based with a wind threat. The small hail threat (if there is one) would be slightly north of the stationary front in the morning, the wind threat would be along and south of it as the outflow boundary surges forward and pops storms across the front in the afternoon.

This post has been edited by ClicheVortex2014: May 11 2018, 06:57 PM


--------------------
Meteorology undergrad at Ohio University (weather on campus)

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
Go to the top of the page
 
+Quote Post
PlanetMaster
post May 11 2018, 08:47 PM
Post #16




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





QUOTE(ClicheVortex2014 @ May 11 2018, 07:55 PM) *
Yeah, there is really strong convergence along that front. We're seeing that now in Michigan, and later tonight more storms will pop in Iowa which will move east, nearly parallel to the stationary front.

I'm thinking this convection will be the trigger for the severe weather event tomorrow, as is often the case for summer MCS events. Usually it becomes elevated with a small hail threat before it becomes surface-based with a wind threat. The small hail threat (if there is one) would be slightly north of the stationary front in the morning, the wind threat would be along and south of it as the outflow boundary surges forward and pops storms across the front in the afternoon.


Makes sense and depending how intense those storms become could be some decent hail as the 850's are close to freezing in central NY around that time.

I don't think I have ever seen a stationary front not only stretch across the country but in such a manner, quite the sight.
Attached Image


--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
PlanetMaster
post May 11 2018, 09:01 PM
Post #17




Rank: F5 Superstorm
***

Group: Member
Posts: 1,633
Joined: 11-January 11
From: Babylon, NY
Member No.: 25,093





How about some OBS?

Very dry here ATM
Overcast
66F
Humidity 32%
Wind Speed Calm
Barometer 30.10 in (1019.1 mb)
Dew 35F

Radar



--------------------
Join in the conversation at https://www.wxdisco.com/
Go to the top of the page
 
+Quote Post
ClicheVortex2014
post May 11 2018, 09:09 PM
Post #18




Rank: F5 Superstorm
***

Group: Member
Posts: 22,676
Joined: 21-April 14
From: Dayton, Ohio
Member No.: 29,453





NAM has the cluster hitting all of PA except for SW PA. I'm much more interested in the near-term models than NAM at this point though.


--------------------
Meteorology undergrad at Ohio University (weather on campus)

Historic weather events in the Ohio Valley:
- The 1974 Super Outbreak (read more)
- The 2012 "Super" Derecho
- The Great Blizzard of 1978

2018 Weather for Cincinnati

Days >90: 18 (Last: 7/14/18) (Highest: 96)
Days <0: 5 (Last 1/6/18) (Lowest: -7)
Marginal risks: 19 (Last: 7/10/18)
Slight risks: 6 (Last: 6/26/18)
Enhanced risks: 0 (Last: 11/5/17)
Moderate risks: 2 (Last: 7/20/18)
High risks: 0 (Last: 11/17/13)
Go to the top of the page
 
+Quote Post
so_whats_happeni...
post May 11 2018, 10:14 PM
Post #19




Rank: F5 Superstorm
***

Group: Member
Posts: 15,153
Joined: 23-March 08
From: Millersville, PA
Member No.: 14,460





QUOTE(phillyfan @ May 11 2018, 01:56 PM) *
Is this for the severe weather tomorrow as well. Slight Risk has been upgraded to enhanced now:

Attached Image



QUOTE(ClicheVortex2014 @ May 11 2018, 04:39 PM) *
Having trouble quoting on this thread for some reason but yeah this is looking like a classic NW flow severe event. First one of the year for this latitude, although there has been some ridge topping MCSs over the past 2 days in the Plains.

This is one of those things where Id be nervous if I was in the bullseye at this point, just as Id be nervous if I was in the bullseye for snow 72+ hours out.



QUOTE(ClicheVortex2014 @ May 11 2018, 07:01 PM) *
Latest experimental HRRR lost the MCS.



At night, though, it has a bunch of cells. Discrete activity in Ohio and MCS to the east.

Ohhhh some excitement as of late had a supercell just off to our sw thursday that produced some nice looking clouds very midwest look to it with not a ton of clouds located aroung the storm so you could see the nice structure.

Now we have this coming through tomorrow gotta watch as many have stated where that boundary sets up. We have quite the turning of the low levels taking place across MD and southern PA might have some decent elevated convection tonight with the warm front passage. I knew I should have closed my windows tonight before I left for work.


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

B.S. in Meteorology
Millersville University


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

Stratosphere Discussion:
2016/2017
2017/2018


AccuWeather Forum MidAtl/NE Snowfall Forecasting Champion Winter 2017
Go to the top of the page
 
+Quote Post
so_whats_happeni...
post May 11 2018, 10:52 PM
Post #20




Rank: F5 Superstorm
***

Group: Member
Posts: 15,153
Joined: 23-March 08
From: Millersville, PA
Member No.: 14,460





Have some nice moisture return being picked up on radar across the area.
Attached Image


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

B.S. in Meteorology
Millersville University


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

Stratosphere Discussion:
2016/2017
2017/2018


AccuWeather Forum MidAtl/NE Snowfall Forecasting Champion Winter 2017
Go to the top of the page
 
+Quote Post

32 Pages V   1 2 3 > » 
Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:

 

RSS Lo-Fi Version Time is now: 25th September 2018 - 07:57 PM