Hoosier Posted July 13, 2015 Share Posted July 13, 2015 New NAM seems to want to kick stuff off by 18z. That's a twist. The first MCS comes through Chicagoland around 12z with the next round coming early in the afternoon as you said. Link to comment Share on other sites More sharing options...
Stebo Posted July 13, 2015 Share Posted July 13, 2015 New NAM seems to want to kick stuff off by 18z. 4km NAM is having none of what the 12km NAM is saying. Honestly I don't know if I would buy the 12km NAM's solution it actually starts stuff near Eau Claire at 12Z and grows upscale. Link to comment Share on other sites More sharing options...
CanadianGuy Posted July 13, 2015 Share Posted July 13, 2015 Any inside word on what the SPC is thinking regarding tomorrow? First high risk of the year? The wording seemed pretty strong on the last outlook. Sent from my GT-N8010 using Tapatalk Link to comment Share on other sites More sharing options...
Hoosier Posted July 13, 2015 Share Posted July 13, 2015 And then round 3 hits Chicago area around midnight tomorrow night. Link to comment Share on other sites More sharing options...
Thundersnow12 Posted July 13, 2015 Share Posted July 13, 2015 4km NAM still holding things off till mid-late afternoon. Goes boom across eastern IA 22/23z Link to comment Share on other sites More sharing options...
jojo762 Posted July 13, 2015 Share Posted July 13, 2015 4km NAM is having none of what the 12km NAM is saying. Honestly I don't know if I would buy the 12km NAM's solution it actually starts stuff near Eau Claire at 12Z and grows upscale. Crazier things have happened with the NAM being right.. But meh. Doubt that any decent new convective development, besides maybe some showery MCS related activity preceding the line, could take place that early. However, given the jet dynamics in place, there could be ample forcing for this to occur. Link to comment Share on other sites More sharing options...
Thundersnow12 Posted July 13, 2015 Share Posted July 13, 2015 And then round 3 hits Chicago area around midnight tomorrow night. Look at that round on the 700mb UVV progs. Link to comment Share on other sites More sharing options...
Geos Posted July 13, 2015 Share Posted July 13, 2015 RPM for Monday morning from WGN Chicago Looks nasty! I say Milwaukee and Chicago both see some good action early tomorrow morning and likely later on too after a recovery. ARX put this out just a short time ago. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 13, 2015 Share Posted July 13, 2015 Looks nasty! I say Milwaukee and Chicago both see some good action early tomorrow morning and likely later on too after a recovery. ARX put this out just a short time ago. Interesting. 12km NAM has the MCS going in a more easterly motion than that. Link to comment Share on other sites More sharing options...
Geos Posted July 13, 2015 Share Posted July 13, 2015 Interesting. 12km NAM has the MCS going in a more easterly motion than that. I guess they're thinking it will turn right and follow the warm front...? I would think with the higher dewpoints and instability west of here it will start to turn. Outflow boundary taking shape to the northwest of Minneapolis. Link to comment Share on other sites More sharing options...
Chicago WX Posted July 13, 2015 Share Posted July 13, 2015 0z 4km NAM breaks a cell off from the QC line tomorrow night. Naturally it passes close to IKK. Link to comment Share on other sites More sharing options...
TimChgo9 Posted July 13, 2015 Share Posted July 13, 2015 So, the initial MCS by sunrise or so..... Then the follow up, sometime in the late afternoon. Now is this contingent on the clearing of any remnants from the mornings storms? Any chance of this going high risk? Or for that matter happening at all? Not trolling, asking a serious question. Link to comment Share on other sites More sharing options...
geddyweather Posted July 13, 2015 Share Posted July 13, 2015 Alek's scenario is not impossible, but it would take extensive morning convection and lingering extensive clouds to make it a greater possibility. Well, it's happened before this year. Multiple times actually... I'm not saying it will happen again (especially with the parameters we've seen this week), but the option is always on the table with the year we've had. I've enjoyed some of the soundings and graphs posted so far. Absurd CAPE numbers like this don't happen very often (last I remember things this jacked was 6/29/11). Saved a number of these for posterity. I think there is a definite possibility of some great severe tomorrow barring anything unforeseen. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 13, 2015 Share Posted July 13, 2015 I guess they're thinking it will turn right and follow the warm front...? I would think with the higher dewpoints and instability west of here it will start to turn. 12km NAM has a strong easterly push of the MUCAPE gradient/warm front between 06z and 12z, and the MCS follows that. At 12z, the MUCAPE gradient is almost perfectly on the entire OH/IN border. Link to comment Share on other sites More sharing options...
Chitown Storm Posted July 13, 2015 Share Posted July 13, 2015 Here she comes. Outflow setting up nicely north of the metro. The only kicker with this is that it's coming from the north. My garage takes on water from this direction when big storms hit as I'm below street level. Might be a long night. Link to comment Share on other sites More sharing options...
Gilbertfly Posted July 13, 2015 Share Posted July 13, 2015 Here she comes. Outflow setting up nicely north of the metro. The only kicker with this is that it's coming from the north. My garage takes on water from this direction when big storms hit as I'm below street level. Might be a long night. Hang tight....best of luck Link to comment Share on other sites More sharing options...
Hoosier Posted July 13, 2015 Share Posted July 13, 2015 AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 946 PM CDT SUN JUL 12 2015 UPDATE 946 PM CDT CONVECTIVE TRENDS...BOTH TO OUR NORTHWEST...AND OVER NORTHERN ILLINOIS...WILL BE THE MAIN CONCERN LATER TONIGHT INTO EARLY MONDAY. WATER VAPOR IMAGERY EARLY THIS EVENING DEPICTS A RATHER STOUT WEST- SOUTHWESTERLY UPPER LEVEL JET ACROSS WY AND SD...WEDGED BETWEEN A LARGE SUBTROPICAL RIDGE CENTERED OVER TX AND A DISTURBANCE OVER SOUTHEASTERN SASKATCHEWAN. THE EVENING 00 UTC RAOBS INDICATE THAT THIS JET IS AROUND 90 KT AT 300 MB...PER KUNR REPORT. SEVERE CONVECTION CONTINUES TO DEVELOP WITHIN THE LEFT EXIT REGION OF THIS UPPER JET OVER NORTHERN MN. THIS CONVECTION IS BEGINNING TO SHOW SIGNS OF BUILDING UPSCALE AND BECOMING COLD POOL DOMINATED. AS SUCH...THE 850MB TO 300 MB THICKNESS AND THE INSTABILITY GRADIENT SUGGESTS THIS ACTIVITY WILL LIKELY BECOME A FORWARD PROPAGATING MCS TOWARDS THE SOUTHEAST...IN THE VICINTY OF A WARM FRONTAL BOUNDARY...WHERE THE ENVIRONMENT IS VERY UNSTABLE. CURRENT TIMING WOULD NOT BRING THIS AREA OF CONVECTION INTO THE AREA UNTIL AFTER 3 TO 4 AM. STRONG DAMAGING WIND GUSTS WOULD BE THE PRIMARY CONCERN WITH THESE STORMS OVER NORTHERN ILLINOIS AROUND OR A COUPLE HOURS PRIOR TO DAYBREAK. ADDITIONAL SCATTERED STORMS MAY ALSO TRY TO DEVELOP OVER THE AREA...WITHIN THE VICINTY OF THE WARM FRONTAL BOUNDARY OVER THE NEXT COUPLE OF HOURS. THE 00 UTC SOUNDINGS AT KILX AND KDVN BOTH INDICATE VERY UNSTABLE CONDITIONS WITH UPWARDS OF 4000 J/KG SBCAPE VALUES...AND LITTLE TO NO CAPPING. WITH THIS IN MIND...AND THE FACT THAT THERE IS A VERY HIGH THETA-E AIRMASS NEAR THE SURFACE BOUNDARY...IT WILL LIKELY NOT TAKE MUCH TO GET SOME ELEVATED ACTIVITY TO DEVELOP. VARIOUS CAMS (CONVECTION ALLOWING MODELS) SUGGEST THAT SCATTERED DEVELOPMENT WILL OCCUR OVER THE AREA...AHEAD OF THE MAIN MCS...LATER THIS EVENING AND OVERNIGHT AS WARM AIR ADVECTION AND ASCENT OCCURS ATOP THE SURFACE BOUNDARY. THIS ACTIVITY COULD POSS A THREAT OF ISOLATED LARGER HAIL GIVEN THE PRESENCE OF STEEP MID-LEVEL LAPSE RATES. HOWEVER...OF MORE CONCERN IS THE HEAVY RAIN THREAT...ESPECIALLY CONSIDERING THERE IS ALREADY ONGOING FLOODING OVER PORTIONS OF THE AREA. PWATS ARE SITTING RIGHT AROUND 1.8" PER THE 00 UTC RAOBS AT KDVN AND KILX...SO THIS WILL CERTAINLY ALLOW ANY STORMS TO PRODUCE TORRENTIAL DOWNPOURS...POTENTIALLY TO AROUND...IF NOT OVER...2 INCHES PER HOUR. AS FOR THE SEVERE THREAT LATER MONDAY INTO MONDAY EVENING...UNCERTAINTY STILL EXISTS AS TO HOW THE EARLY MORNING ACTIVITY WILL EVOLVE. THIS WILL PLAY A BIG ROLE IN THE MESOSCALE ENVIRONMENT...DETAILS WHICH CANNOT REASONABLY BE RESOLVED AT THIS DISTANCE. SYNOPTICALLY IT STILL APPEARS IT WILL BE A VERY FAVORABLE ENVRIONMENT FOR BOTH HP SUPERCELLS WITH ATTENDENT LARGE HAIL...DAMAGING WIND...TORNADO...AND FLOODING RAIN THREAT AS WELL AS BOW ECHOS WITH DAMAGING WINDS ON MONDAY AFTERNOON AND EVENING. THEREFORE...GIVEN THE MESOSCALE UNCERTAINTIES AT THIS TIME...THE CURRENT THINKING HAS NOT CHANGED WITH RESPECT TO THE POTENTIAL FOR SOME SIGNIFICANT SEVERE THUNDERSTORMS OVER OR NEAR THE AREA. KJB Link to comment Share on other sites More sharing options...
Geos Posted July 13, 2015 Share Posted July 13, 2015 Nice informative discussion^ Yes, good luck Chitown - hopefully you don't have to stay up later than planned tonight. Gust front about to enter Hennepin County. Link to comment Share on other sites More sharing options...
HillsdaleMIWeather Posted July 13, 2015 Share Posted July 13, 2015 I'm pulling an all nighter for this. REV UP THAT COFFEE MAKER Nice looking MCS in MN. Link to comment Share on other sites More sharing options...
Hoosier Posted July 13, 2015 Share Posted July 13, 2015 0z 4km NAM breaks a cell off from the QC line tomorrow night. Naturally it passes close to IKK. output_FNNQIy.gif Another look, with county outlines Noticed some interesting things in the model fields. Check out the localized strong 850 mb winds near that cell. Also, the model tries to back the low level flow out ahead. Link to comment Share on other sites More sharing options...
Chitown Storm Posted July 13, 2015 Share Posted July 13, 2015 Thanks guys, hopefully it's not too bad, although reports of torrential rains coming in. Now under a tornado watch and t-storm watch, til 1am and 4am respectively. EDIT: t-storm watch replaces the tornado watch. I didn't think that was right when it said both were active at the same time. Link to comment Share on other sites More sharing options...
beavis1729 Posted July 13, 2015 Share Posted July 13, 2015 Dewpoints in central & eastern Iowa...assuming all of the stations are accurate: Ames 77 Des Moines 78 Waterloo 78 Ottumwa 78 Ankeny 79 Cedar Rapids 79 Charles City 81 Des Moines is 87/78 (heat index of 100) at 9 PM...yuck. Link to comment Share on other sites More sharing options...
daddylonglegs Posted July 13, 2015 Share Posted July 13, 2015 Severe tstorm watch up for lse... too bad its not going to be here until 3 or 4 am Link to comment Share on other sites More sharing options...
jojo762 Posted July 13, 2015 Share Posted July 13, 2015 A bit OT, but love when WFO's do mesoscale discussions either the night before, or morning of a potentially big severe event just to give a good update of the situation. LOT seems especially good at doing this as well. Link to comment Share on other sites More sharing options...
tornadotony Posted July 13, 2015 Share Posted July 13, 2015 A bit OT, but love when WFO's do mesoscale discussions either the night before, or morning of a potentially big severe event just to give a good update of the situation. LOT seems especially good at doing this as well. They do a lot of things really well when it comes to severe and winter wx ops. Link to comment Share on other sites More sharing options...
Geos Posted July 13, 2015 Share Posted July 13, 2015 Highest wind report out of MPX so far. 0945 PM TSTM WND GST HASTY 45.37N 93.97W07/12/2015 E58 MPH WRIGHT MN MESONETRWIS ROAD SENSOR Link to comment Share on other sites More sharing options...
MattPetrulli Posted July 13, 2015 Share Posted July 13, 2015 Seems SPC will go high risk if there's enough clearing. Tornado outbreak not out of mind either. They'll probably go high risk with a 60% for wind/hail and a 15% risk for tornadoes unless the cells are a lot more discrete in central IL. But my tornado area would be Central IL with very high instability and efficient shear and a 80 Knot mid-layer flow. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 13, 2015 Share Posted July 13, 2015 This is from SPC... top left is the observed radar... the rest are the models' interpretations. Link to comment Share on other sites More sharing options...
Wmsptwx Posted July 13, 2015 Share Posted July 13, 2015 So far strong gust reported from what I'm looking at but nothing crazy(could very well be wrong.) Link to comment Share on other sites More sharing options...
samdman95 Posted July 13, 2015 Share Posted July 13, 2015 not from the area but spending some in chicago so forgive my ignorance. Any estimate on when i should set my alarm so I can wake up in time for this MCS?thankssssssss Link to comment Share on other sites More sharing options...
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