Jump to content
  • Member Statistics

    17,588
    Total Members
    7,904
    Most Online
    LopezElliana
    Newest Member
    LopezElliana
    Joined

T-Storms Part 2 : "North and West of the city!"


TalcottWx

Recommended Posts

  • Replies 2.2k
  • Created
  • Last Reply

Most of southern New England is seeing dew-points between about 70-73 right now. Fuel is there, but the timing with a few other pieces to the puzzle is still somewhat of a question mark. If things get messy with random storms already firing by midday, that may mitigate the threat. Ideally I think we'd want to hold off until later on for a strong line or perhaps even a line with a few discretes out in front. Fun time for some bangers and Kev may be right in the thick of it. ASOUT

Link to comment
Share on other sites

Keep that faint line of cu/showers across western Mass. at bay and we'll continue to ramp up the environment into the afternoon. HRRR keeps insisting on primary development over the next few hours and that's part of why it ticks the threat down a bit later this afternoon. I'm actually mildly intrigued by this setup today.

Link to comment
Share on other sites

We are starting to see those stronger 0-6km shear values tick back northward...hopefully not too much more and hopefully the stronger values work in before convection gets going.  

 

Seeing several stations continuing to hold onto a S or SE sfc wind is really making things rather interesting...especially for any discrete that get going which will likely happen early on.  

Link to comment
Share on other sites

We are starting to see those stronger 0-6km shear values tick back northward...hopefully not too much more and hopefully the stronger values work in before convection gets going.  

 

Seeing several stations continuing to hold onto a S or SE sfc wind is really making things rather interesting...especially for any discrete that get going which will likely happen early on.

11 a.m. mesoanalysis already shows sig tor values over 0.5 across western southern New England. Could this be a rare event this year where things actually line up for a decent severe setup? We'll soon find out.
Link to comment
Share on other sites

..TRENDS IN MOSAIC RADAR IMAGERY INDICATED AN
OUTFLOW BOUNDARY LEFT OVER FROM FRIDAY EVENING/OVERNIGHT CONVECTION
EXTENDED FROM NRN KY THROUGH NRN WV...SOUTH-CENTRAL TO NERN PA TO
NRN VT.

...NEW ENGLAND/NORTHEAST U.S. TO THE CENTRAL APPALACHIANS...
EARLY MORNING VISIBLE SATELLITE IMAGERY SUGGESTS THE GREATEST
SURFACE HEATING SHOULD OCCUR EAST AND SOUTH OF THE LATTER CONVECTIVE
BOUNDARY DESCRIBED IN THE SYNOPSIS...

Link to comment
Share on other sites

11 a.m. mesoanalysis already shows sig tor values over 0.5 across western southern New England. Could this be a rare event this year where things actually line up for a decent severe setup? We'll soon find out.

 

The lapse rates are poor but that should be compensated somewhat by the large cape values thanks to dews in the lower 70's.  Ekster always said if you want to overcome crappy mlvl lapse rates get dews into the lower 70's.  

 

I wish the shear was stronger but given the cape values I think it is adequate enough and the models do hint that those stronger values could work in with the convection.  

 

It's quite an intriguing setup.

Link to comment
Share on other sites

Anyone east of this line you have dwindling hope ... Any one west, you have very little or no hope.

 

This is the nope line.  The west side of the nope line can be compensated by fresh diabatic heating; does the feebling summer sun bring the goods?   Proobably, but there cloud contamination there so doubtful.

 

This boundary separates yesterday's residual outflow from evening overnight Lakes action, from lesser adulterated air. It is out ahead of the cold front by a 300 km or so, and though the air mass may feel the same on either side of this boundary, and even appear the same at in the T/TD, these demarcation lines still tend to delineate regions that are a quanta less stable from those that have better positive buoyancy.  

post-904-0-18970400-1410019376_thumb.jpg

Link to comment
Share on other sites

I'm going to go ahead and completely disagree with you.

Anyone east of this line you have dwindling hope ... Any one west, you have very little or no hope.

This is the nope line. The west side of the nope line can be compensated by fresh diabatic heating; does the feebling summer sun bring the goods? Proobably, but there cloud contamination there so doubtful.

This boundary separates yesterday's residual outflow from evening overnight Lakes action, from lesser adulterated air. It is out ahead of the cold front by a 300 km or so, and though the air mass may feel the same on either side of this boundary, and even appear the same at in the T/TD, these demarcation lines still tend to delineate regions that are a quanta less stable from those that have better positive buoyancy.

Link to comment
Share on other sites

I'm going to go ahead and completely disagree with you.

 

One thing I left out is that the nope line is moving east... It's covered the distance between ALB to central Mass in about 2.5 hours.  

 

It may yet dissipate as diabatic heating tries to normalize the air mass on either side, but the cloud contamination (particularly at our latitude at this time of dimming sun-angles..) is a killer.  We'll have to see on that.  

 

The forced ascent is missing from this though, so these other distracting factors become louder as forces in them selves.  

Link to comment
Share on other sites

The lapse rates are poor but that should be compensated somewhat by the large cape values thanks to dews in the lower 70's.  Ekster always said if you want to overcome crappy mlvl lapse rates get dews into the lower 70's.  

 

I wish the shear was stronger but given the cape values I think it is adequate enough and the models do hint that those stronger values could work in with the convection.  

 

It's quite an intriguing setup.

 

The shear here in Michigan yesterday was slightly weaker/farther removed than Southern New England's (though our CAPE values were slightly higher) and we still ended up with widespread wind damage with gusts exceeding hurricane force in a couple places. Something in the neighborhood of 400,000 customers were without power, which is a lot by our standards (as a means of comparison metro Detroit has about 3.7 million citizens whereas metro Boston has 4.5). 

Link to comment
Share on other sites

The shear here in Michigan yesterday was slightly weaker/farther removed than Southern New England's (though our CAPE values were slightly higher) and we still ended up with widespread wind damage with gusts exceeding hurricane force in a couple places. Something in the neighborhood of 400,000 customers were without power, which is a lot by our standards. 

 

You also had better synoptic forcing out that way, yesterday.. .This whole cyclone flow aloft that's arriving is being sheared and muted some by the fact that it's running into compressed quasi-Bermuda ridge, so the dynamics are bit weaker. 

 

There is an index finger rule, though, that if one is trying to predict severe in SNE, look to Michigan the day before.  The devil of disappointment is in the details though.

 

It'll be interesting to see how this gets wasted or used, either way.

Link to comment
Share on other sites

The shear here in Michigan yesterday was slightly weaker/farther removed than Southern New England's (though our CAPE values were slightly higher) and we still ended up with widespread wind damage with gusts exceeding hurricane force in a couple places. Something in the neighborhood of 400,000 customers were without power, which is a lot by our standards. 

 

You guys got crushed pretty good.  

Link to comment
Share on other sites

After 0.01" from some showers we're right back to 80F/73F under BKN/THN OVC skies. There's still plenty of soup behind that line.

 

Right ... never in contention

 

to say again: despite that appeal, both in feel and measure, these "lines" have a tendency to demarcate action from lesser or inaction.  

 

It's definitely possible to overcome that, again ... if the sun can diabatically normalize things.  We'll just have to wait and see.  

Link to comment
Share on other sites

mcd1687.gif

MESOSCALE DISCUSSION 1687
NWS STORM PREDICTION CENTER NORMAN OK
1131 AM CDT SAT SEP 06 2014

AREAS AFFECTED...NEW ENGLAND INTO ERN PA/NRN NJ

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY

VALID 061631Z - 061800Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...BROKEN BANDS OF STRONG TO SEVERE THUNDERSTORMS WILL
DEVELOP THIS AFTERNOON AHEAD OF A COLD FRONT AND TRACK E/NE ACROSS
ERN PA/NRN NJ INTO NEW ENGLAND. DAMAGING WINDS WILL BE THE MAIN
THREAT WITH THESE STORMS. A WATCH WILL LIKELY BE NEEDED WITHIN THE
NEXT 1-2 HOURS.

DISCUSSION...TEMPERATURES HAVE WARMED INTO THE 80S EARLY THIS
AFTERNOON IN BROKEN CLOUDINESS AHEAD OF THE SFC COLD
FRONT...RESULTING IN MODERATE DESTABILIZATION /MLCAPE APPROACHING
2000 J/KG/ OF THE VERY MOIST BOUNDARY LAYER /LOW 70S DEWPOINTS/.
AREAS OF AGITATED CUMULUS WERE EVIDENT ON LATEST VIS SATELLITE
IMAGERY FROM CENTRAL PA NEWD INTO NEW ENGLAND IN THE VICINITY WEAK
SFC CONFLUENCE ZONES. THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE
NEXT HOUR OR SO IN THE VICINITY OF THIS MODEST SFC CONVERGENCE AHEAD
OF THE MAIN COLD FRONT FROM ERN PA INTO S NY/N NJ. EFFECTIVE SHEAR
AROUND 30-40 KT WILL BE ADEQUATE FOR SOME ORGANIZED STORM
CLUSTERS/LINE SEGMENTS. WHILE MIDLEVEL LAPSE RATES WILL REMAIN
POOR...STRONG SFC HEATING HAS RESULTED IN STEEP LOW LEVEL LAPSE
RATES...AND COMBINED WITH PW VALUES AOA 1.75 INCHES...STRONG
/LOCALLY DAMAGING/ WINDS WILL BE POSSIBLE WITH BROKEN BANDS OF
CONVECTION. ADDITIONAL STORMS WILL DEVELOP FURTHER N/NE INTO NEW
ENGLAND ALONG THE COLD FRONT LATER THIS AFTERNOON.

A WATCH WILL LIKELY BE NEEDED IN THE NEXT 1-2 HOURS.

..LEITMAN/CORFIDI.. 09/06/2014


ATTN...WFO...CAR...GYX...BOX...BTV...OKX...ALY...PHI...BGM...
CTP...

LAT...LON 40947232 40277394 40157516 40307616 40557702 40867728
41287735 41457720 42317614 43307451 44037318 45527011
46596801 46636776 46226731 45496713 44986720 44466785
41617137 40947232

Link to comment
Share on other sites

One thing I left out is that the nope line is moving east... It's covered the distance between ALB to central Mass in about 2.5 hours.

It may yet dissipate as diabatic heating tries to normalize the air mass on either side, but the cloud contamination (particularly at our latitude at this time of dimming sun-angles..) is a killer. We'll have to see on that.

The forced ascent is missing from this though, so these other distracting factors become louder as forces in them selves.

okay now that you explained your thoughts further i have no problem lol
Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.

×
×
  • Create New...