IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 Looks like we're starting to destabilize nicely. SPC has upgraded us to a slight risk for severe storms today. Effective bulk shear profiles are in the 30-40kt range which should be enough to maintain storms as they slide southeast later today. Any activity should ride the southern periphery of the strongest wind field. Although the models have been focusing a majority of the activity over New England we should still do well. Link to comment Share on other sites More sharing options...
NEG NAO Posted June 17, 2014 Share Posted June 17, 2014 Its one event, which was a derecho. I think he was talking about general MCS' which usually tend to move from the NW and dive ESE bingo - east southeast not nw to se - case closed - next ? Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 bingo - east southeast not nw to se - case closed - next ? Read more, post less. If you're going to call out a poster and tell them that they are wrong you're expected to bring more to the table then one event and no scientific evidence. Link to comment Share on other sites More sharing options...
Stormlover74 Posted June 17, 2014 Share Posted June 17, 2014 Looks like we're starting to destabilize nicely. SPC has upgraded us to a slight risk for severe storms today. Effective bulk shear profiles are in the 30-40kt range which should be enough to maintain storms as they slide southeast later today. Any activity should ride the southern periphery of the strongest wind field. Although the models have been focusing a majority of the activity over New England we should still do well. Earthlight has a good write up on NYMetroweather (since he has abandoned us all here) Link to comment Share on other sites More sharing options...
NEG NAO Posted June 17, 2014 Share Posted June 17, 2014 Read more, post less. If you're going to call out a poster and tell them that they are wrong you're expected to bring more to the table then one event and no scientific evidence. Since you are calling me out and want to continue the P contest- read this article and the different types of MCS's - it mentions movement and tell me me where it says they move almost always move NW to SE - obviously there are a number of exceptions to the rule- not just the 1998 one - also look at my total number of posts compared to yours and we have been here close to the same amount of time http://www.wxonline.info/topics/mcsprop.html Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 From Earthlight http://www.nymetroweather.com/ Link to comment Share on other sites More sharing options...
NEG NAO Posted June 17, 2014 Share Posted June 17, 2014 From Earthlight http://www.nymetroweather.com/ he mentions east southeast movement - I would think this favors the northern half of the metro Link to comment Share on other sites More sharing options...
SmokeEater Posted June 17, 2014 Share Posted June 17, 2014 he mentions east southeast movement - I would think this favors the northern half of the metroIt favors no one, because you have no idea where the track will be until the MCS forms. Very hard to pin a track down. And btw, I almost never agree with yanks, but he's right. I'll back him up on this one. Look at 2012, it formed in IA, and moved ESE and barely pounded me here in SJ. 99% of them move from NW to SE. Link to comment Share on other sites More sharing options...
PB GFI Posted June 17, 2014 Share Posted June 17, 2014 SPC AC 170533DAY 2 CONVECTIVE OUTLOOKNWS STORM PREDICTION CENTER NORMAN OK1233 AM CDT TUE JUN 17 2014VALID 181200Z - 191200Z...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN PLAINS EWD TOPA...AND ACROSS THE CNTRL HIGH PLAINS..NRN IL EWD INTO PA... STORMS ARE EXPECTED TO BE ONGOING EARLY ON WED ACROSS LOWER MI ANDPERHAPS ERN WI ASSOCIATED WITH A COMPACT SHORTWAVE TROUGH. THISFEATURE WILL CONTINUE EWD DURING THE DAY...WHILE DESTABILIZATIONOCCURS WITHIN THE WEAK SFC TROUGH. WIDESPREAD STORMS ARE EXPECTED BYLATE AFTERNOON FROM NRN IL/IND EWD INTO PA AND SRN NY.UNIDIRECTIONAL WIND PROFILES WILL FAVOR MAINLY FORWARD PROPAGATINGSTORMS CAPABLE OF DAMAGING WINDS...BUT INSTABILITY WILL ALSO BESUFFICIENT FOR HAIL. WITH AMPLE WLY FLOW...STORMS SHOULD REMAINSTRONG ALL THE WAY TO THE COAST. Link to comment Share on other sites More sharing options...
REDMK6GLI Posted June 17, 2014 Share Posted June 17, 2014 SPC AC 170533 DAY 2 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1233 AM CDT TUE JUN 17 2014 VALID 181200Z - 191200Z ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN PLAINS EWD TO PA...AND ACROSS THE CNTRL HIGH PLAINS..NRN IL EWD INTO PA... STORMS ARE EXPECTED TO BE ONGOING EARLY ON WED ACROSS LOWER MI AND PERHAPS ERN WI ASSOCIATED WITH A COMPACT SHORTWAVE TROUGH. THIS FEATURE WILL CONTINUE EWD DURING THE DAY...WHILE DESTABILIZATION OCCURS WITHIN THE WEAK SFC TROUGH. WIDESPREAD STORMS ARE EXPECTED BY LATE AFTERNOON FROM NRN IL/IND EWD INTO PA AND SRN NY. UNIDIRECTIONAL WIND PROFILES WILL FAVOR MAINLY FORWARD PROPAGATING STORMS CAPABLE OF DAMAGING WINDS...BUT INSTABILITY WILL ALSO BE SUFFICIENT FOR HAIL. WITH AMPLE WLY FLOW...STORMS SHOULD REMAIN STRONG ALL THE WAY TO THE COAST. We will see paul. Last year that derecho that passed into our area was forecasted to hold its strength all the way into the coastal areas and it just fell apart to showers and some lightning by the time it reached NYC-east. However im pretty optimistic about this forecasted severe threat tommorow..... Link to comment Share on other sites More sharing options...
PB GFI Posted June 17, 2014 Share Posted June 17, 2014 We will see paul. Last year that derecho that passed into our area was forecasted to hold its strength all the way into the coastal areas and it just fell apart to showers and some lightning by the time it reached NYC-east. However im pretty optimistic about this forecasted severe threat tommorow..... They love to split once to NYC . We will see . Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 Well latest day one has scaled back coverage. Still about half the area remains in slight risk. Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 As many have said, tomorrow looks to be our day. Hopefully we don't get another let down. Link to comment Share on other sites More sharing options...
Isotherm Posted June 17, 2014 Share Posted June 17, 2014 As many have said, tomorrow looks to be our day. Hopefully we don't get another let down. That's the wrong attitude to go into it with. What you should be saying is, "I anticipate nothing, but if there's something, I'll be pleasantly surprised." Too many unknowns with convection forecasting to get those hopes off the floor beyond a couple hours in advance. Link to comment Share on other sites More sharing options...
Dsnowx53 Posted June 17, 2014 Share Posted June 17, 2014 Shear vectors favor ESE movement. Link to comment Share on other sites More sharing options...
Stormlover74 Posted June 17, 2014 Share Posted June 17, 2014 As many have said, tomorrow looks to be our day. Hopefully we don't get another let down. Regardless if 99% of the area gets thunderstorms someone will manage to be let down or cry bust Link to comment Share on other sites More sharing options...
NEG NAO Posted June 17, 2014 Share Posted June 17, 2014 It favors no one, because you have no idea where the track will be until the MCS forms. Very hard to pin a track down. And btw, I almost never agree with yanks, but he's right. I'll back him up on this one. Look at 2012, it formed in IA, and moved ESE and barely pounded me here in SJ. 99% of them move from NW to SE. does anyone know of site where there is a listing of MCS' over a period of time ? Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 does anyone know of site where there is a listing of MCS' over a period of time ? Everyone here is telling you that you're wrong, normally a sign that you are. Link to comment Share on other sites More sharing options...
Chaser25973 Posted June 17, 2014 Share Posted June 17, 2014 I won't be happy until there is a wall cloud directly over Manhattan! Link to comment Share on other sites More sharing options...
Dsnowx53 Posted June 17, 2014 Share Posted June 17, 2014 I still feel that any diurnal convection in our area will generally be capped today. The SPC Mesoanalysis doesn't show CIN values less than 25 -- though it really should. This is today's 12z NAM valid at 2:00pm. We'll have to rely on a localized boundary for any isolated convection. We may have to wait until tonight for the MCS for any real convection. Link to comment Share on other sites More sharing options...
Chaser25973 Posted June 17, 2014 Share Posted June 17, 2014 I still feel that any dirunal convection in our area will generally be capped today. The SPC Mesoanalysis doesn't show CIN values less than 25 -- though it really should. This is today's 12z NAM valid at 2:00pm. We'll have to rely on a localized boundary for any isolated convection. We may have to wait until tonight for the MCS for any real convection. If we get some good storms tonight, won't that effect tomorrow's potential? Link to comment Share on other sites More sharing options...
NEG NAO Posted June 17, 2014 Share Posted June 17, 2014 Everyone here is telling you that you're wrong, normally a sign that you are. prove me wrong find me the list of MCS with graphics - > 50- I know one thing for certain 99% do not move exactly NW to SE as Smoke Eater claims Link to comment Share on other sites More sharing options...
SnoSki14 Posted June 17, 2014 Share Posted June 17, 2014 I expect nothing at all and no one should either. Trust me as long as you believe that then you won't be disappointed. Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 prove me wrong find me the list of MCS with graphics - I know one thing for certain 99% do not move exactly NW to SE as you claim I have better things to do with my life. You're on an island with this one. Link to comment Share on other sites More sharing options...
BxEngine Posted June 17, 2014 Share Posted June 17, 2014 prove me wrong find me the list of MCS with graphics - > 50- I know one thing for certain 99% do not move exactly NW to SE as Smoke Eater claims No one is discussing EXACT motions here, but general ideas. And if you want proof of things, you should be willing to back up your own claim of the 99% number, right? You pick some odd nitpicky sh*t to get completely soap boxy about. Link to comment Share on other sites More sharing options...
Isotherm Posted June 17, 2014 Share Posted June 17, 2014 If one examines the synoptic-scale set-up that tends to precede derecho / MCS type events, it's apparent that it would be very difficult to get a derecho moving anything other than W-E or WNW-ESE/NW-SE. They feed off of tight baroclinic zones with high dews points/heat to the south, cooler/drier air to the north, and usually strong W-E or NW-SE mid level winds. It's generally in a ring of fire regime where you have a large ridge in the central or southern US and convection fires along the periphery of said ridge. Thus it makes sense for the convection to travel generally NW-SE (or WNW-ESE) as the mid level flow around high pressure is clockwise and in that direction on its northern side. Strong jet streaks can help maintain the events overnight after they've developed from the intense instability and gradient along the boundary. Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 If one examines the synoptic-scale set-up that tends to precede derecho / MCS type events, it's apparent that it would be very difficult to get a derecho moving anything other than W-E or WNW-ESE/NW-SE. They feed off of tight baroclinic zones with high dews points/heat to the south, cooler/drier air to the north, and usually strong W-E or NW-SE mid level winds. It's generally in a ring of fire regime where you have a large ridge in the central or southern US and convection fires along the periphery of said ridge. Thus it makes sense for the convection to travel generally NW-SE (or WNW-ESE) as the mid level flow around high pressure is clockwise and in that direction on its northern side. Strong jet streaks can help maintain the events overnight after they've developed from the intense instability and gradient along the boundary. Nice post. I also found this explanation useful. This behavior results from a characteristic pattern of propagation, in which new cells tend to form on the general upwind side of the cluster, with the larger and more intense cells developing on its right flank. The individual cells move through the cluster, dissipating on approach to its advancing and left flanks. Preferential formation of cells toward the rear side of the cluster is shown to be compatible with the probable origin and trajectories (relative to the moving storm) of air ascending from the lower part of the subcloud layer. The sometimes-observed rapid movement of large multicellular storms to left of the mean wind is partly accounted for by an opposite (left forward flank) pattern of propagation. Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 Removed from day 2 slight risk on latest update Link to comment Share on other sites More sharing options...
IsentropicLift Posted June 17, 2014 Share Posted June 17, 2014 You can see the moisture diving southeast as it crosses the northern periphery of the ridge axis poking up to our southwest. Most of the high res models indeed show convection diving southeastward or even southward but weakening before it arrives or dissipating all together. In my opinion the current parameters would be capable of supporting a convective complex well into the evening. Derecheo composites are starting to rise some. We'll have to watch and see if the better mid-level lapse rates can continue to advect towards the region thanks to an EML coming east. Link to comment Share on other sites More sharing options...
Dsnowx53 Posted June 17, 2014 Share Posted June 17, 2014 Excellent post, Tom. Large MCS's generally (but not always) move just south of due east, due to the synoptic patterns that set them up. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.