Tim from Springfield (IL) Posted July 3, 2011 Share Posted July 3, 2011 SPC Day 3 outlook (July 5) currently has a slight risk knocking on my door--for most of central and eastern Iowa, northwest and west-central Illinois (to about Rockford, Peoria and Springfield), northern Missouri, and parts of southeast Minnesota and southwest Wisconsin. http://www.spc.noaa.gov/products/outlook/day3otlk.html Link to comment Share on other sites More sharing options...
andyhb Posted July 3, 2011 Share Posted July 3, 2011 Middle to later next week looks interesting for the northern conus, pretty strong upper trough moving through. Link to comment Share on other sites More sharing options...
baroclinic_instability Posted July 3, 2011 Share Posted July 3, 2011 Middle to later next week looks interesting for the northern conus, pretty strong upper trough moving through. Classic setup for the northern plains. The outbreaks/big severe events up there like a strong wave passing through Canada with fast westerly mid-level flow and more subtle height falls across the northern tier of states and good directional low/mid level turning with no crazy looking hodographs associated with strong waves ejecting from the intermountain W, rapidly deepening, and lifting NE. Strong cold fronts/quasi drylines originating off the MT rockies do the work of initiation--no need for perfectly timed height falls to help erode the cap. Still fantasy land but UK/CMC/Euro would be potentially significant up there. Reminds me a little of the Northwood Aug 26, 2007 tornado event although that event featured a far more subtle shortwave in Canada. Link to comment Share on other sites More sharing options...
baroclinic_instability Posted July 3, 2011 Share Posted July 3, 2011 SPC briefly mentions the threat potential in the long. "INITIALLY...ON DAY 4/WEDNESDAY...AT LEAST AN ISOLATED SEVERE TSTM THREAT MAY BE POSSIBLE ALONG/AHEAD OF AN ADVANCING COLD FRONT ACROSS AREAS SUCH AS THE OH VALLEY/NORTHEAST STATES/NEW ENGLAND...AND PERHAPS ACROSS THE CENTRAL HIGH PLAINS WITHIN A POST-FRONTAL UPSLOPE REGIME. THEREAFTER...TIED TO THE AFOREMENTIONED PROGGED NORTHWEST CONUS/WESTERN CANADA UPPER TROUGH...CURRENT INDICATIONS ARE THAT THE SEVERE POTENTIAL WILL LIKELY INCREASE/GENERALLY DEVELOP EASTWARD EACH DAY WITHIN A CORRIDOR FROM THE NORTHERN INTERMOUNTAIN REGION/NORTHERN GREAT DIVIDE VICINITY TO THE NORTHERN PLAINS BETWEEN DAYS 5-7 THURSDAY-SATURDAY. WHILE A SEVERE THREAT SEEMS PROBABLE ACROSS THESE REGIONS DURING THE PERIOD...CURRENT FORECAST UNCERTAINTY/VARIABILITY PRECLUDE A DELINEATION OF ANY 30 PERCENT EQUIVALENT SEVERE RISK AREAS." Link to comment Share on other sites More sharing options...
Derek30 Posted July 3, 2011 Share Posted July 3, 2011 baro, you think that southern Manitoba would be in the risk zone? Looks like it could be a multiple day event if the low closes off like some models are showing. Link to comment Share on other sites More sharing options...
andyhb Posted July 3, 2011 Share Posted July 3, 2011 Yes, I believe so, Manitoba is also in the direct path of that strong trough, and it reminds me a little of the setup before the Elie tornado in 2007. Will be watching this very closely. Link to comment Share on other sites More sharing options...
baroclinic_instability Posted July 3, 2011 Share Posted July 3, 2011 baro, you think that southern Manitoba would be in the risk zone? Looks like it could be a multiple day event if the low closes off like some models are showing. Absolutely, even the weak GFS solution would have severe potential up there. Link to comment Share on other sites More sharing options...
hurricaneman Posted July 4, 2011 Share Posted July 4, 2011 Looks like it could be one of those severe weather days for that portion of Canada Link to comment Share on other sites More sharing options...
andyhb Posted July 4, 2011 Share Posted July 4, 2011 I'll be quite surprised if we don't see some 4-6 day outlines from the SPC. Link to comment Share on other sites More sharing options...
Derek30 Posted July 4, 2011 Share Posted July 4, 2011 Now you guys are really getting me fired up. I hate getting all worked up about a threat 5 days from now but it's so hard not to. It's just rare to get a system of that strength in July up here. Everything looks good now but the cap worries me a bit. Link to comment Share on other sites More sharing options...
andyhb Posted July 4, 2011 Share Posted July 4, 2011 Classic setup for the northern plains. The outbreaks/big severe events up there like a strong wave passing through Canada with fast westerly mid-level flow and more subtle height falls across the northern tier of states and good directional low/mid level turning with no crazy looking hodographs associated with strong waves ejecting from the intermountain W, rapidly deepening, and lifting NE. Strong cold fronts/quasi drylines originating off the MT rockies do the work of initiation--no need for perfectly timed height falls to help erode the cap. Still fantasy land but UK/CMC/Euro would be potentially significant up there. Reminds me a little of the Northwood Aug 26, 2007 tornado event although that event featured a far more subtle shortwave in Canada. Link to comment Share on other sites More sharing options...
Derek30 Posted July 4, 2011 Share Posted July 4, 2011 I just think back to last Thursday, June 30th. A lot of impressive dynamics (5,000+ J/KG of CAPE, 50 kts of shear). Delayed shortwave arrival plus a very strong cap led to a bust for ND/MN/MB. The Plains had capping problems all spring with the ridging down there. Link to comment Share on other sites More sharing options...
cmichweather Posted July 4, 2011 Share Posted July 4, 2011 I just think back to last Thursday, June 30th. A lot of impressive dynamics (5,000+ J/KG of CAPE, 50 kts of shear). Delayed shortwave arrival plus a very strong cap led to a bust for ND/MN/MB. The Plains had capping problems all spring with the ridging down there. I got tricked into thinking we'd have enough mid level cooling with the trough and the height falls but anytime you see 30 C 850 it doesn't really matter unless you have a mega front coming with a 40 degree temp swing it just would have taken an incredible amount of surface convergence/forcing to get a surface parcel to overcome that cap and me and the spc included thought that the cap would erode. Caps that strong almost never erode, tomorrow the cap will erode and we'll have some hail throughout the valley, you'll probably miss the storms to the south. The next threat is impressive and if the SW is as strong as the ECMWF has then yes we'll break the cap and see several strong supercells with that sort of set up. Link to comment Share on other sites More sharing options...
andyhb Posted July 4, 2011 Share Posted July 4, 2011 Very favorable-looking hodographs continue to be forecasted for the aforementioned period across the Northern Plains. The cap doesn't look nearly as strong as it did a week ago when everything got snuffed out. Edit: No 4-6 day outlook, hmmmm. Link to comment Share on other sites More sharing options...
wisconsinwx Posted July 4, 2011 Share Posted July 4, 2011 Yet another opportunity for storms will go wasted, it looks like. We haven't even seen any rain for a couple weeks, and it looks like it might extend about another week, unless we get something tomorrow night. Link to comment Share on other sites More sharing options...
Chicago Storm Posted July 4, 2011 Share Posted July 4, 2011 Yet another opportunity for storms will go wasted, it looks like. We haven't even seen any rain for a couple weeks, and it looks like it might extend about another week, unless we get something tomorrow night. Will you stfu already. Link to comment Share on other sites More sharing options...
andyhb Posted July 4, 2011 Share Posted July 4, 2011 GFS seems to be in more agreement now about the trough being stronger than all these weaker shortwaves we've seen over the past couple of weeks. On another note: Happy 4th of July. Link to comment Share on other sites More sharing options...
baroclinic_instability Posted July 4, 2011 Share Posted July 4, 2011 Very favorable-looking hodographs continue to be forecasted for the aforementioned period across the Northern Plains. The cap doesn't look nearly as strong as it did a week ago when everything got snuffed out. Edit: No 4-6 day outlook, hmmmm. I don't blame them, GFS coming around a little, but there is still inter-model timing differences (even amongst the EC and UK which have been the most bullish...there are still timing differences in terms of trough displacement) as well as significant differences in strength (weaker GFS and amped UK/EC). I don't think I would outline 30% probs this far out either--especially considering the fact convection is more fickle in the high plains of eastern MT/western ND and into the central northern plains than other areas of the US. Link to comment Share on other sites More sharing options...
baroclinic_instability Posted July 4, 2011 Share Posted July 4, 2011 I got tricked into thinking we'd have enough mid level cooling with the trough and the height falls but anytime you see 30 C 850 it doesn't really matter unless you have a mega front coming with a 40 degree temp swing it just would have taken an incredible amount of surface convergence/forcing to get a surface parcel to overcome that cap and me and the spc included thought that the cap would erode. Caps that strong almost never erode, tomorrow the cap will erode and we'll have some hail throughout the valley, you'll probably miss the storms to the south. The next threat is impressive and if the SW is as strong as the ECMWF has then yes we'll break the cap and see several strong supercells with that sort of set up. I think that one would have had a chance if it weren't for that slow moving PV across the intermountain W coming in a day and a half later than initially progged by the GFS and a day later than the EC. The slow timing messed up everything, and the PV also weakened considerably in that time frame as quite a bit of deep boundary layer warming as well as the influence of the terrain helped weaken it considerably. How often is the NAM-WRF operational actually the ONLY correct solution--especially when it is way slower? Almost never--I was shocked too. Link to comment Share on other sites More sharing options...
Derek30 Posted July 4, 2011 Share Posted July 4, 2011 Friday looks to be biggest day here in southern Manitoba, as of right now. Could be a bit more of a later event with the front remaining west of the region. Going to rely on a bit of a low level jet, too. Liking the way the pattern is shaping up. The northern Plains and southern Prairies could be on the northern periphery of the ridge for awhile, judging by the long range models. Link to comment Share on other sites More sharing options...
andyhb Posted July 4, 2011 Share Posted July 4, 2011 I didn't really expect much tornadic potential today, but it seems it still managed to form some serious storms, the next setup is only looking more favorable at this point. Link to comment Share on other sites More sharing options...
Derek30 Posted July 5, 2011 Share Posted July 5, 2011 What are your thoughts on storm mode? GFS is still pretty weak with the system. Doesn't show CAPE values getting up much more than 2,000 J/KG. Link to comment Share on other sites More sharing options...
baroclinic_instability Posted July 5, 2011 Share Posted July 5, 2011 18Z GFS ensemble mean really ramping things up--I glanced at the individual members and the 18Z operational GFS is one of the weakest solutions. Link to comment Share on other sites More sharing options...
baroclinic_instability Posted July 5, 2011 Share Posted July 5, 2011 What are your thoughts on storm mode? GFS is still pretty weak with the system. Doesn't show CAPE values getting up much more than 2,000 J/KG. Depends on which scenario you are considering. The stronger solutions such as the EC/UK would most definitely yield discrete supercells initiating along the cold front. The eventual mode after initiation is highly unclear though as the speed of the wave at that time will have a significant influence on whether things congeal into a strong linear system along the front. Not to mention when are looking at multiple potential storm days--so I guess it also depends on which day you are asking about. Link to comment Share on other sites More sharing options...
Derek30 Posted July 5, 2011 Share Posted July 5, 2011 Thanks for your responses, baro. Really appreciate and respect your opinion here! From what I can tell, there will possibly be a threat of elevated storms here in southern Manitoba as early as Thursday night. Severe storms are possible in western ND up into southwestern Manitoba on Friday with activity possibly merging into an MCS as the low level jet increases. Activity would then push to the ENE with mainly a hail and wind threat into central North Dakota/south central Manitoba. Not sure about Saturday. Depends on the timing of the front. That's what I see. Not sure if I'm looking at things right, though! Link to comment Share on other sites More sharing options...
andyhb Posted July 5, 2011 Share Posted July 5, 2011 To be honest, the northern plains are overdue for a tornado outbreak, I haven't seen one up there in awhile (at least since the June 17th, 2010 Minnesota/North Dakota tornado event). Link to comment Share on other sites More sharing options...
Derek30 Posted July 5, 2011 Share Posted July 5, 2011 Yeah, there hasn't been one since the time you mentioned. The pattern looks good from here on out, though. Looks like the next threat could be a decent opportunity of seeing some tornadic supercells. Link to comment Share on other sites More sharing options...
andyhb Posted July 5, 2011 Share Posted July 5, 2011 Considering June was quite below average, I'm rather eager to see what happens for the rest of the year. Here's to hoping we don't see anymore disasters in the south this fall (their second season). Edit: And for once the cap doesn't seem to be much of a problem. Link to comment Share on other sites More sharing options...
tornadotony Posted July 5, 2011 Share Posted July 5, 2011 To be honest, the northern plains are overdue for a tornado outbreak, I haven't seen one up there in awhile (at least since the June 17th, 2010 Minnesota/North Dakota tornado event). Ehh, they're not really overdue for one. That area typically only gets a significant outbreak every few years. Link to comment Share on other sites More sharing options...
Derek30 Posted July 5, 2011 Share Posted July 5, 2011 Any thoughts on the threat later this week, Tony? Link to comment Share on other sites More sharing options...
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