General Thunderstorm Discussion: Late June

[CoastalWx]

You just tweeted storms will be firing

 

There seems to be two different mechanisms firing storms. Here it's seabreeze/weak srfc trough overhead. Out that way a s/w will be moving and to help fire storms, but clouds moved in quickly there. Give it an hour or so, but it's possible it may be meh there.

[Tropopause_Fold]

You just tweeted storms will be firing

i do wish you could manage to separate this board from other things. 

[CoastalWx]

Can you post the HRRR

 

It's easier if I post the link because then you can loop the comp reflectivity.

 

http://rapidrefresh.noaa.gov/HRRR/jsloopLocalDiskDateDomainZip.cgi?dsKeys=hrrr_jet:&runTime=2013062614&plotName=cref_t3sfc&fcstInc=60&numFcsts=16&model=hrrr&ptitle=HRRR%20Model%20Fields%20-%20Experimental&maxFcstLen=15&fcstStrLen=-1&resizePlot=1&domain=t3

[CT Rain]

There seems to be two different mechanisms firing storms. Here it's seabreeze/weak srfc trough overhead. Out that way a s/w will be moving and to help fire storms, but clouds moved in quickly there. Give it an hour or so, but it's possible it may be meh there.

 

We'll see some... but yeah pretty meh. Instability will underperform out this way.

[Damage In Tolland]

There seems to be two different mechanisms firing storms. Here it's seabreeze/weak srfc trough overhead. Out that way a s/w will be moving and to help fire storms, but clouds moved in quickly there. Give it an hour or so, but it's possible it may be meh there.

Theres a lot of breaks showing up on viz and even some clearing out in NY state. I wonder if they fire out there first and give us time to move this mid deck out if here ?

[CoastalWx]

We'll see some... but yeah pretty meh. Instability will underperform out this way.

 

I thought we'd have a little more sun today over CT. Lets see what happens over the next 60-90 min, but some just may not have damage today.

[CoastalWx]

Theres a lot of breaks showing up on viz and even some clearing out in NY state. I wonder if they fire out there first and give us time to move this mid deck out if here ?

 

Just let things cook a bit. Lapse rates suck which doesn't help, but it's only 1pm.

[CT Rain]

I thought we'd have a little more sun today over CT. Lets see what happens over the next 60-90 min, but some just may not have damage today.

 

Yeah as did I. Not every storm can be damaging. 

[Tropopause_Fold]

SE MA might be a good spot. Bob's area...as stuff from the west comes in along with a few localized boundaries coming up from the south and in from the east

[Quincy]

It was showing light showers in a highly unstable atmosphere?

Take a look: (still issues for animated gifs??)

[Damage In Tolland]

Take a look:

animatedHRRR.gif

That looks like a nice line for us later

[CoastalWx]

SE MA might be a good spot. Bob's area...as stuff from the west comes in along with a few localized boundaries coming up from the south and in from the east

 

GFS has been nailing that area since yesterday.

[CT Rain]

That looks like a nice line for us later

 

The HRRR is also way overdoing mixed layer CAPE back this way. With the showers and clouds moving in I don't expect severe in CT today. Thunderstorms may be tough to come by. 

 

The showers have really blossomed in the last hour or so and that continues. 

[CT Rain]

GFS has been nailing that area since yesterday.

 

Yeah I agree. I like the area S and SW of Boston. 

[Damage In Tolland]

The HRRR is also way overdoing mixed layer CAPE back this way. With the showers and clouds moving in I don't expect severe in CT today. Thunderstorms may be tough to come by.

The showers have really blossomed in the last hour or so and that continues.

Plenty of sun behind them. Give it time. Patience

[CoastalWx]

SPC WRF still brings stuff through so lets give it some time.

[CoastalWx]

The HRRR is also way overdoing mixed layer CAPE back this way. With the showers and clouds moving in I don't expect severe in CT today. Thunderstorms may be tough to come by. 

 

The showers have really blossomed in the last hour or so and that continues. 

 

I wonder if the SPC WRF does the same. Really goes to town, but is it right? I could see RI and SE MA getting it good I suppose.

[Baroclinic Zone]

GFS has been nailing that area since yesterday.

 

I just noticed that on today's 12z run.  Hate to say it but I could use the rain.  Ground has dried out substantially over the last week with no precip falling at TAN in that timeframe.  Only 0.17" in the last 12 days.

[CT Rain]

I wonder if the SPC WRF does the same. Really goes to town, but is it right? I could see RI and SE MA getting it good I suppose.

 

Yeah I think the issue is is that the hires models started developing surface based convection earlier but as it turned out the QG forcing ahead of the shortwave coupled with enough sb CIN wound up producing a strengthening batch of showers/mid level clouds. 

 

The 12z SPC WRF went to town with sb convection right off the bat and that's clearly not happening. With horrific mid level lapse rates and plenty of clouds and rain I think this threat is just about done back this way. 

[Damage In Tolland]

There's our storms for later firing out in East Central NY state.

[HalloweenGale]

Can see a tower off to the north.

[weatherwiz]

The problem certainly isn't instability.  SBcape values across CT are up to 2000 J/KG, MLcapes 1500 J/KG, MUcapes 2000 J/KG, LI values of -4C to -6C, Ncape values though only around 0.1 so Cape profiles are certainly skinny.  The better forcing from the RFQ of the ULJ is still to the north and west of SNE as is the better forcing/height falls associated with the s/w

 

One issue is this may be a much later show and by that time instability will be weakening.  With that said, I still think we see widespread storms but severe will be isolated.  

[Damage In Tolland]

The problem certainly isn't instability. SBcape values across CT are up to 2000 J/KG, MLcapes 1500 J/KG, MUcapes 2000 J/KG, LI values of -4C to -6C, Ncape values though only around 0.1 so Cape profiles are certainly skinny. The better forcing from the RFQ of the ULJ is still to the north and west of SNE as is the better forcing/height falls associated with the s/w

One issue is this may be a much later show and by that time instability will be weakening. With that said, I still think we see widespread storms but severe will be isolated.

Yeah it's very unstable. That isn't an issue

[weatherwiz]

slight risk tomorrow across extreme western CT/MA

 

...ERN CONUS...
WITH AMPLIFICATION OF THE TROUGH IN THE EAST...LOW/MID-LEVEL FLOW
WILL BECOME AT LEAST MODERATE. COMBINED WITH INCREASING LARGE-SCALE
ASCENT AND 60S TO LOWER 70S SURFACE DEW POINTS...SETUP SHOULD YIELD
FAIRLY WIDESPREAD CONVECTION ON THU AFTERNOON/EVENING. THE MOST
ROBUST COMBINATION OF CAPE/SHEAR SHOULD EXIST ACROSS PARTS OF THE
SOUTHEAST WHERE 500 MB NWLYS SHOULD REACH 25-35 KT AMIDST A STRONGLY
UNSTABLE AIR MASS. HERE...TSTM CLUSTERS WILL BE CAPABLE OF BOTH
SEVERE WIND/HAIL. ACROSS THE MID-ATLANTIC/NORTHEAST...UNCERTAINTY
EXISTS OVER THE DEGREE OF INSTABILITY WITH NRN EXTENT. BUT WITH
PROBABLE CYCLOGENESIS...EVEN MODEST HEATING SHOULD SUPPORT A RISK
FOR DAMAGING WINDS AND A COUPLE OF TORNADOES.

[weatherwiz]

Yeah it's very unstable. That isn't an issue

 

certainly not as high as the past few days but that's borderline moderate instability.  

[Quincy]

slight risk tomorrow across extreme western CT/MA

 

...ERN CONUS...

WITH AMPLIFICATION OF THE TROUGH IN THE EAST...LOW/MID-LEVEL FLOW

WILL BECOME AT LEAST MODERATE. COMBINED WITH INCREASING LARGE-SCALE

ASCENT AND 60S TO LOWER 70S SURFACE DEW POINTS...SETUP SHOULD YIELD

FAIRLY WIDESPREAD CONVECTION ON THU AFTERNOON/EVENING. THE MOST

ROBUST COMBINATION OF CAPE/SHEAR SHOULD EXIST ACROSS PARTS OF THE

SOUTHEAST WHERE 500 MB NWLYS SHOULD REACH 25-35 KT AMIDST A STRONGLY

UNSTABLE AIR MASS. HERE...TSTM CLUSTERS WILL BE CAPABLE OF BOTH

SEVERE WIND/HAIL. ACROSS THE MID-ATLANTIC/NORTHEAST...UNCERTAINTY

EXISTS OVER THE DEGREE OF INSTABILITY WITH NRN EXTENT. BUT WITH

PROBABLE CYCLOGENESIS...EVEN MODEST HEATING SHOULD SUPPORT A RISK

FOR DAMAGING WINDS AND A COUPLE OF TORNADOES.

Was just about to post that. 4 days in a row:

[CT Rain]

The problem certainly isn't instability.  SBcape values across CT are up to 2000 J/KG, MLcapes 1500 J/KG, MUcapes 2000 J/KG, LI values of -4C to -6C, Ncape values though only around 0.1 so Cape profiles are certainly skinny.  The better forcing from the RFQ of the ULJ is still to the north and west of SNE as is the better forcing/height falls associated with the s/w

 

One issue is this may be a much later show and by that time instability will be weakening.  With that said, I still think we see widespread storms but severe will be isolated.  

 

Ehhhhh... I dunno. If you change the model on the SPC mesoanalysis to the experimental map you can see that there's plenty of MLCIN over SE NY and MLCAPE values around 500-1000 j/kg. 

[CoastalWx]

Yeah I think the issue is is that the hires models started developing surface based convection earlier but as it turned out the QG forcing ahead of the shortwave coupled with enough sb CIN wound up producing a strengthening batch of showers/mid level clouds. 

 

The 12z SPC WRF went to town with sb convection right off the bat and that's clearly not happening. With horrific mid level lapse rates and plenty of clouds and rain I think this threat is just about done back this way. 

 

It's funny because the mid level clouds tell you forcing is there...but then it inhibits heating. My gut says storms will fire in ern NY state, but I wonder how organized it will be.

[CoastalWx]

Yeah guys, use MLCAPE. That gives you a better picture of the lower levels instead of SBCAPE. At least IMHO.

[weatherwiz]

Ehhhhh... I dunno. If you change the model on the SPC mesoanalysis to the experimental map you can see that there's plenty of MLCIN over SE NY and MLCAPE values around 500-1000 j/kg. 

 

Oh wow...I never knew you could do that.  Certainly much different