wizard021

Looks like tomorrow in eastern NC looks to get wild. 

https://gyazo.com/9dd164ff286dd168c1f4ac81a43ddf83

http://www.eas.slu.edu/CIPS/ANALOG/IMAGES/SPC/2010/2010042506_024_ptsvr.png Good analog 

http://www.meteo.psu.edu/fxg1/NARR/2010/us0424.php

Based on all the 500 mb maps off the past 15 years , this is the best analog and it is 3rd in CIPS for tomorrow (yazoo city).

Messy .  

http://www.meteo.psu.edu/fxg1/NARR/2014/us0428.php

You want broad trough , not a compact ejecting upper low.  Look for waves to rotate around the trough to spark an outbreak. 

http://www.meteo.psu.edu/fxg1/NARR/2011/us0427.php

Look for s/w rotating around broad trough axis. 

Tomorrow's system is a southern stream upper low that remains  an upper low and not broad.  In the back of your head you should look for what can go wrong. Typically wind fields will be veer back veer, or speed of the system is not ideal. Also usually cloud cover with these southern stream vorts doesn't allow sufficient build up of 03 km cape. 

https://gyazo.com/4e21b68ed657c4990f86f67510a89971 Veer back veer noted around 2 -3 km . 

Summary looks for storms to be on going in morning, but move north of the warm front. Storms should take off after 23z Se arkansas and move quickly east in a messy band into north Alabamy overnight. 1 or 2 tornadoes and swaths of wind are likely.  Hail generally under 2.5 inches. 

Just now, wizard021 said:

Rule of thumb .. closed upper lows that close in the west and then move east are never historic outbreaks . There is always some issue that prevents it . Systems that eject and then close off near the wark sector result in outbreaks. Also broad troughs with no closed lows are preferred even more .

However a localized notable event can occur .

Rule of thumb .. closed upper lows that close in the west and then move east are never historic outbreaks . There is always some issue that prevents it . Systems that eject and then close off near the wark sector result in outbreaks. Also broad troughs with no closed lows are preferred even more .

22 minutes ago, Wmsptwx said:

Thinking they upgrade to high risk on Day 1,, all the ingredients are there.

No. Messy storm mode with storms struggling . By dark 1 or 2 will get sustained and deliver bad results though. 

Yazoo city messy storm mode likely. High risk unlikely. 1 or 2 qlcs embedded sup likely. 

Models focus tornado risk mainly after dark. 

Yes Thursday looks like the bigger day .

https://www.tropicaltidbits.com/analysis/models/?model=gem&region=us&pkg=uv250 as modeled you will see a clustering of hail with large cape and lapse rates and 40 to 50kt 06km shear .  Low level shear generally weak 850 to 700mb.  Gfs and nam too fast as always. 

If it speeds up the upper jet is fairly weak. The low level wind response will not result in a big outbreak. Ceiling is 10 percent locally in backed wind along wf.

1 hour ago, MattPetrulli said:

SREF already at 60 for 00z Thursday.

Cmc very slow moving upper low and it arrives Wed night . This supports weak ll shear.  Marginal slight risk warranted mainly for large hail.

https://www.spc.noaa.gov/climo/reports/140427_rpts.html https://www.spc.noaa.gov/products/outlook/archive/2014/day1otlk_20140427_2000.html

https://www.spc.noaa.gov/climo/reports/140427_rpts.html

Just now, StormChaser4Life said:

Definitely did not rival a high risk day. Yes that storm was very impressive but that was the only truly cyclic beast of the day. Yes there were other tornadoes but were relatively short lived and not long tracked. 

April 27 2014 also had only 1 long tracker .   The instability area was limited so many areas east were not going to get impacted.  

12 minutes ago, StormChaser4Life said:

Outside the Happy, TX storm today wasn't overly eventful from a tornado standpoint. I think that storm having more deviant motion off the front really enhanced its tornado potential. Other storms large paralleled the boundary and inflows were consistently getting contaminated by the next storm down the line. I think slower movement of cutoff low which isn't surprising lead to the flow paralleling the boundary instead of it being more orthogonal to it. Storms really struggled to get east off it into open warm sector. The best instability ended up setting up west where cirrus thinned sooner. Low level lapse rates and sfc based cape were not overly impressive in the eastern panhandle. Not a bad chase day for March but hopefully this season we can see some quality warm sector storms that aren't an HP mess in the Plains. Definitely a tricky chase today. Lots of storms to choose from. 

There was a storm with maxed out rotation today.  Today rivaled many high risk days including  April 27 2014 ... its just the area is not populated .

1 minute ago, StormChaser4Life said:

 

Well given that storm mode is significantly less discrete than it was earlier may not see like we did earlier with that storm. Not saying significant tornadoes can't happen in the moderate risk. Just seems like now the supercells are merging largely. But will likely still see spin ups given the shear. Could be more QLCS related though. We shall see. 

Its an outlook, nobody cares . What happens is happening. 

Should be rain soon in Brooklyn

9 minutes ago, Allsnow said:

Use cc off radar scope 

Over to rain . It stuck to roads for a bit.

Just now, EpicHECS said:

How do they think this is lasting through tomorrow PM? It's clearly tapering off from west to east now. 

Back side will reform overnight with scattered echos. 

Just now, MANDA said:

Pure sleet here in Mt. Arlington now.

Temp 21.5 degrees.

New snow 3.6" right at time of changeover.

Didn't think sleet would get this far NW.

Just surged NW in a hurry.  Win for the 3K NAM.

I did think it would.

5 minutes ago, MJO812 said:

Insane that some areas to our south are close to 10 inches.

Yeh those areas were getting slammed all morning, banding stalled there for a while .

2 minutes ago, MJO812 said:

Insane that some areas to our south are close to 10 inches.

NAM 3km Model - Tropical Tidbits - Google Chrome (gyazo.com)

Concerned about the warm layer by 17z.

3 minutes ago, jm1220 said:

The sleet is being held SW of Philly for now. It will head NE but I'm pretty confident that the vast majority of this subforum won't have snow amounts knocked down much if at all by sleet (outside maybe the Monmouth County people who already have a lot). Now until 2-3pm is when we get 90% of what falls I think. Borderline moderate here now. 

Soundings suggest nyc turns to sleet at 12pm.