Powerball Posted July 7, 2015 Share Posted July 7, 2015 Location and coverage (as always) are in question, but there's a pretty good signal for a ROF setup in our region during the period noted in the title. Even if shear isn't all that impressive, the decent low-level convergence being progged, a NE expansion of the EML (850mb temps of 20*C+) and the corresponding high instability values should aid in the setup. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 7, 2015 Share Posted July 7, 2015 GFS has maintained some crazy parameters and I can't wait to see what happens when we get in range of the NAM. The thing that concerns me is that SPC is far from impressed with the setup. DAY 4-8 CONVECTIVE OUTLOOKNWS STORM PREDICTION CENTER NORMAN OK0350 AM CDT TUE JUL 07 2015VALID 101200Z - 151200Z...DISCUSSION...THE LATEST MEDIUM RANGE GUIDANCE CONTINUES TO SUGGEST THAT A FAIRLYPROMINENT SUBTROPICAL HIGH CENTER WILL REDEVELOP WEST NORTHWESTWARDFROM THE SOUTHEASTERN U.S. INTO THE SOUTHERN PLAINS AND SOUTHERNROCKIES REGION LATE THIS WEEK THROUGH THE WEEKEND. AN AMPLIFIEDRIDGE APPEARS LIKELY TO BUILD ALONG AN AXIS NORTH OF THE HIGH CENTERTHROUGH THE PLAINS INTO PORTIONS OF THE CANADIAN PRAIRIES...FLANKEDBY TROUGHING NEAR THE PACIFIC COAST AND ACROSS THE EAST. THISREGIME MAY BE ACCOMPANIED BY THE DEVELOPMENT OF MODERATE TO STRONGPOTENTIAL INSTABILITY...PARTICULARLY ACROSS PARTS OF THE NORTHERNPLAINS INTO THE MID MISSOURI VALLEY...ASSOCIATED WITH STEEPENINGMID-LEVEL LAPSE RATES AND THE RETURN OF SEASONABLY MOIST BOUNDARYLAYER CONDITIONS. WITHIN THE WESTERLY/NORTHWESTERLY MID/UPPER FLOWON THE NORTHERN AND EASTERN PERIPHERY OF THE RIDGE...THE ENVIRONMENTMAY BECOME INCREASINGLY CONDUCIVE TO THE DEVELOPMENT OF ORGANIZEDTHUNDERSTORM CLUSTERS. HOWEVER...THE PREDICTABILITY OF A MOREPRECISE LOCATION OF WHERE THESE CLUSTERS MAY FORM ON ANY GIVEN DAYTHIS WEEKEND INTO EARLY NEXT WEEK REMAINS LOW. AND...THERE REMAINSLITTLE IN THE MODEL OUTPUT TO SUGGEST ANYTHING BEYOND RELATIVELYMINOR OR MARGINAL /FOR THE SEASON/ SEVERE WEATHER POTENTIAL. AS ARESULT...SEVERE WEATHER PROBABILITIES APPEAR TO REMAIN BELOW 15PERCENT THROUGH THE PERIOD. Link to comment Share on other sites More sharing options...
Hoosier Posted July 7, 2015 Share Posted July 7, 2015 Mid level flow doesn't look too good at this point. I wouldn't write off this period though. Link to comment Share on other sites More sharing options...
TimChgo9 Posted July 9, 2015 Share Posted July 9, 2015 Not much being said about weekend rain, other than Skilling saying something about "drenching thunderstorms". Link to comment Share on other sites More sharing options...
Hoosier Posted July 9, 2015 Share Posted July 9, 2015 Marginal risk on the day 3 outlook. Given the amount of instability available to feed these complexes, you can't rule out one or more of them taking off and resulting in a better severe threat. Barring some sort of MCV enhancement or something, the mid-level flow still looks a bit marginal, but it's not awful especially given the instability. Link to comment Share on other sites More sharing options...
Hoosier Posted July 9, 2015 Share Posted July 9, 2015 Flooding concerns going to ramp up again as well. Link to comment Share on other sites More sharing options...
TimChgo9 Posted July 9, 2015 Share Posted July 9, 2015 From LOT's AFD this morning. SATURDAY THROUGH WEDNESDAY...WARM/MOIST PUSH APPEARS TO REALLY GET GOING SATURDAY THROUGH THEREST OF THE WEEKEND...WITH MORE SUMMER LIKE CONDITIONS EXPECTEDTHROUGH EARLY NEXT WEEK. MODELS DO VARY WITH REGARDS TOTHUNDERSTORM CHANCES...ALTHOUGH...THE PERIOD APPEARS TO CONTINUETO BE ACTIVE. THERE IS THUNDERSTORM CHANCES DURING THE DAYSATURDAY BUT WILL BE PARTLY DRIVEN BY WHERE LIFTING WARM FRONT ISSITUATED...WITH MODELS STRUGGLING WITH AT THIS TIME.HOWEVER...GUIDANCE IS HINTING AT A BETTER POSSIBILITY FOR MOREORGANIZED DEVELOPMENT SATURDAY NIGHT INTO EARLY SUNDAY MORNING.STILL UNCERTAINTY PRESENT...BUT A POSSIBLE SCENARIO WILL BE FORMCS DEVELOPMENT TO THE WEST/NORTHWEST SHIFTING ACROSS THE CWADURING THIS TIME. IF THIS WERE TO OCCUR... DAMAGING WINDS ANDHEAVY RAINFALL WOULD BE POSSIBLE. ONCE AGAIN...STILL SOMEUNCERTAINTY...BUT SYNOPTIC SETUP WITH INCREASINGMOISTURE/INSTABILITY WOULD SUPPORT THIS POSSIBILITY AT THIS TIME. RODRIGUEZ Link to comment Share on other sites More sharing options...
brohnhdon Posted July 9, 2015 Share Posted July 9, 2015 Pretty surprised this thread isn't getting very much attention. I'd be extremely surprised if we don't end up seeing a couple of wind driven enhanced if not moderate risk areas on Sunday and Monday. Yeah, shear is only around 40kts, but CAPE is also 4000-6000 J/kg. That's insane without any shear. The NAM shows an explicit MCS Sunday within a very favorable thermodynamic environment. The GFS then absolutely blows up cells on Monday in northern Indiana/Ohio. Looking forward to see how this actually plays out...in my experience this year, the better an event looks far out, the worse it plays out...I hate the models. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 9, 2015 Share Posted July 9, 2015 Pretty surprised this thread isn't getting very much attention. I'd be extremely surprised if we don't end up seeing a couple of wind driven enhanced if not moderate risk areas on Sunday and Monday. Yeah, shear is only around 40kts, but CAPE is also 4000-6000 J/kg. That's insane without any shear. The NAM shows an explicit MCS Sunday within a very favorable thermodynamic environment. The GFS then absolutely blows up cells on Monday in northern Indiana/Ohio. Looking forward to see how this actually plays out...in my experience this year, the better an event looks far out, the worse it plays out...I hate the models. "shear is only around 40 knots" that's easily favorable for MCS development/maintenance. The June 29 derecho thrived with less shear than that (mostly 35 knots). The instability being shown by GFS and NAM is absolutely amazing... this is what we should see in July. Not something like ILX's crappy sounding last night, 60 degrees/60 dew point. Link to comment Share on other sites More sharing options...
cyclone77 Posted July 9, 2015 Share Posted July 9, 2015 Insane cape continues to be advertised by all models late this weekend/early next week. NAM forecast soundings show in excess of 8000j/kg cape (lol) in parts of Iowa late Sunday. Sunday night there could actually be a pretty decent severe weather event with a fairly powerful upper jet plowing in right over the insane instability pool. Decent LLJ support as well. With the seasonally strong upper jet combined with decent shear profiles, and potential extreme instability there could be some derecho potential me thinks. Gonna be very interesting to see how this plays out. Iowa sounding from 18z NAM.. Link to comment Share on other sites More sharing options...
andyhb Posted July 9, 2015 Share Posted July 9, 2015 Several notable matches showing up in the sharppy soundings for some areas, such as 7/13/04, 8/28/90 and 8/6/62 for Topeka. Overall setup is a pretty good match synoptically to some of these huge cape/modest shear setups with the wild card of that enhanced upper level jet. Link to comment Share on other sites More sharing options...
TimChgo9 Posted July 9, 2015 Share Posted July 9, 2015 Looks good for the OV, looks like the development really takes off east of Chicago. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 9, 2015 Share Posted July 9, 2015 I know the whole TORCON thing is rather controversial in the Meteorology world... but since Dr. Forbes is one hell of a Meteorologist, here's his thoughts SATURDAYIsolated severe thunderstorms in northwest, central, and east ND, east SD, northwest, central, and south MN, IA, west WI, northwest and west-central IL, north MO. TORCON - 3 northwest IL, east IA, south MN; 2 rest of area https://scontent-ord1-1.xx.fbcdn.net/hphotos-xaf1/t31.0-8/11411944_10152997021418201_7491500277508803952_o.jpg SUNDAY Isolated severe thunderstorms along and north of a warm front in east ND, northwest, central and south MN, WI, central and south MI, OH, north and central IL, north-central and east IA, north, central, and southeast IN, northeast SD. TORCON - 2 to 3 for now; could be higher in some locations if a low pressure center forms on the front - but models disagree on where that could occur https://scontent-ord1-1.xx.fbcdn.net/hphotos-xpt1/t31.0-8/11143373_10152997077198201_2790698790353582065_o.jpg MONDAY Computer models disagree on the weather pattern, reducing confidence in the details of the forecast. Isolated severe thunderstorm in parts of the area including northeast MN, WI, MI, northeast IL, IN, OH, NY, PA, WV, east KY, east TN, NJ. TORCON - 2 to 3 for now It's weird to go from this crappy November-like weather to full-on mid-summer MCS/derecho season with extreme CAPE within a week. Link to comment Share on other sites More sharing options...
RCNYILWX Posted July 10, 2015 Share Posted July 10, 2015 The afternoon GRB AFD mentioned that one of the CIPS analogs for Sunday is the day of the Oakfield WI F5 tornado. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 10, 2015 Share Posted July 10, 2015 21z SREF mean has nearly 7000 MUCAPE for Des Moines, ~5400 MLCAPE. Unfortunately none of the members hit 10000 MUCAPE. Mean dew point is 78, mean temp is 93. Yikes. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 10, 2015 Share Posted July 10, 2015 Insane cape continues to be advertised by all models late this weekend/early next week. NAM forecast soundings show in excess of 8000j/kg cape (lol) in parts of Iowa late Sunday. Sunday night there could actually be a pretty decent severe weather event with a fairly powerful upper jet plowing in right over the insane instability pool. Decent LLJ support as well. With the seasonally strong upper jet combined with decent shear profiles, and potential extreme instability there could be some derecho potential me thinks. Gonna be very interesting to see how this plays out. Iowa sounding from 18z NAM.. 00z 1 up'd that Link to comment Share on other sites More sharing options...
andyhb Posted July 10, 2015 Share Posted July 10, 2015 3 days out but 00z NAM looks pretty good across a fairly large area of the Upper Midwest on Monday afternoon/evening, particularly through the Upper MS Valley into N IL. Should be decent ascent for initiation especially with the left exit region of the upper jet punching right over the warm sector. Link to comment Share on other sites More sharing options...
Thundersnow12 Posted July 10, 2015 Share Posted July 10, 2015 Pretty much over my house Sunday evening off the 0z NAM Link to comment Share on other sites More sharing options...
Stebo Posted July 10, 2015 Share Posted July 10, 2015 It looks like the NAM is increasing in the shear and with these types of instability numbers it won't take much to get things going. Link to comment Share on other sites More sharing options...
Minnesota Meso Posted July 10, 2015 Share Posted July 10, 2015 Looking at the NAM and GFS it appears that a slight risk will be warranted for Sat (day 2) covering SE MN, NE IA, far Southern WI, and Northern IL. They will most likely post a 15% probability with wording in the text that a upgrade is possible. Link to comment Share on other sites More sharing options...
cyclone77 Posted July 10, 2015 Share Posted July 10, 2015 Pretty much over my house Sunday evening off the 0z NAM house1.gif house2.gif house3.gif Some interesting conditional setups on the way to be sure. With differential heating/old outflow boundaries lying around, remnant MCVs, and who knows what else, it could be an interesting weekend/early week with this upcoming ROF event. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 10, 2015 Share Posted July 10, 2015 Some interesting conditional setups on the way to be sure. With differential heating/old outflow boundaries lying around, remnant MCVs, and who knows what else, it could be an interesting weekend/early week with this upcoming ROF event. OFB roulette Link to comment Share on other sites More sharing options...
HillsdaleMIWeather Posted July 10, 2015 Share Posted July 10, 2015 Most interesting AFD in weeks .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 403 AM EDT FRI JUL 10 2015 WET AND ACTIVE WEATHER IN STORE FOR THE AREA EARLY NEXT WEEK AS "RING OF FIRE" PATTERN DEVELOPS ON NORTHEAST FRINGE OF BUILDING CENTRAL CONUS RIDGE. NUMEROUS SHORTWAVES WILL CASCADE DOWN THE RIDGE INTO OUR REGION AND CAPITALIZE ON MOIST AND UNSTABLE AIRMASS AS THETA-E PLUME FOLDS EAST. UNFORTUNATELY...MESOSCALE (AND ASSOCIATED SENSIBLE WEATHER) DETAILS REMAIN HIGHLY UNCERTAIN AT THIS POINT WITH POTENTIAL FOR CONVECTION TO MODULATE THE TIMING/STRENGTH/PLACEMENT OF INDIVIDUAL WAVES. SATURDAY STILL LOOKING DRY THOUGH WITH STRONG SHORTWAVE RIDGING BETWEEN BOOKEND TROUGHS. HIGH DEGREE OF SUBSIDENCE AND DRY LOWER LEVELS WILL LEAD TO A FAIRLY PLEASANT DAY...THOUGH MID/HIGH CLOUDS WILL BE STEADILY INCREASING. STILL...FILTERED INSOLATION AND SOME WEAK WAA LATE IN THE DAY SHOULD ALLOW HIGH TEMPS TO AT LEAST MOVE SLIGHTLY CLOSER TO SEASONAL AVERAGES WITH LOW 80S EXPECTED. REMOVED ANY MENTION OF PRECIP PRIOR TO 00Z WITH NEARLY ALL GUIDANCE KEEPING OUR CWA DRY THROUGH THAT TIME. PRECIP CHANCES WILL INCREASE FROM WEST TO EAST OVERNIGHT THOUGH AS WAA WING OF NEXT SHORTWAVE PUSHES THROUGH OUR AREA. MODELS SHOW A HEALTHY SWATH OF 305K ISENTROPIC ASCENT AND GOOD MOISTURE ADVECTION IN OUR WESTERN CWA ON THE NOSE OF NOCTURNAL 40 KT LLJ. BUMPED UP POPS BUT STOPPED JUST SHY OF CATEGORICAL FOR NOW. ISENTROPIC ASCENT IS WEAKER DURING THE DAY SUNDAY BUT DOES SHIFT EAST AND WILL HAVE THE ADDED BENEFIT OF SOME DIURNAL DESTABILIZATION. A FEW SEVERE STORMS MAY BE POSSIBLE GIVEN VERY WARM/MOIST AIRMASS BEHIND FRONT (SURFACE DEWPOINTS LOW TO MID 70S) AND DEEP LAYER SHEAR 25-30 KTS BUT MORNING PRECIP/CLOUD COVER MAKES DEGREE OF INSTABILITY UNCERTAIN. HEAVY RAIN/FLOODING ALSO A CONCERN GIVEN RETURN OF 2+ INCH PW VALUES AND DEEP WARM CLOUD LAYERS. CONFIDENCE IN FORECAST DETAILS DROPS SIGNIFICANTLY FOR MONDAY AND TUESDAY WITH MULTIPLE SHORTWAVES PUSHING THROUGH THE REGION IN A MOIST AND POTENTIALLY VERY UNSTABLE ENVIRONMENT. SEVERE WEATHER AND FLOODING MAY BE POSSIBLE BOTH DAYS DEPENDING ON THE EXACT TIMING AND PLACEMENT OF INDIVIDUAL SHORTWAVES AND POTENTIAL MCS'S. NOT SURPRISINGLY...GFS AND ECMWF MODELS OFFER VERY DIFFERENT SOLUTIONS AND UNFORTUNATELY AT THIS POINT CAN DO NOTHING BUT BLANKET MID-HIGH CHANCE POPS UNTIL DETAILS COME BETTER INTO FOCUS. LOOKS LIKE WE COULD SEE A BREAK WEDNESDAY AND THURSDAY BUT AGAIN...MAY DEPEND ON EARLY WEEK CONVECTION. VERY WARM THERMAL PROFILES FOR EARLY NEXT WEEK SUGGEST GOING FORECAST COULD POTENTIALLY BE MUCH TOO COOL. 90F EASILY POSSIBLE WITH SOME GOOD AFTERNOON SUN/MIXING BUT CONFIDENCE IN CLOUD/PRECIP TRENDS TOO LOW FOR ANYTHING MORE THAN MID 80S AT THIS POINT. Link to comment Share on other sites More sharing options...
A-L-E-K Posted July 10, 2015 Share Posted July 10, 2015 Looks like a classic deep summer ROF weekendBest climo Link to comment Share on other sites More sharing options...
A-L-E-K Posted July 10, 2015 Share Posted July 10, 2015 been doing some snooping and i'm pretty happy with the overall setup, with nice wave spacing and favorable diurnal timing for 2-3 real high quality regional MCS events with better than average derecho potential as mentioned above by Cyclone. Link to comment Share on other sites More sharing options...
A-L-E-K Posted July 10, 2015 Share Posted July 10, 2015 12z 4km NAM is a legit emergency level scenario for DVN's CWA Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 10, 2015 Share Posted July 10, 2015 SPC's day 4 outlook sounds excellent. I'm a bit nervous because, just like winter events, if you're in or near the bullseye 4 days out, you're probably gonna get screwed. DAY 4-8 CONVECTIVE OUTLOOKNWS STORM PREDICTION CENTER NORMAN OK0336 AM CDT FRI JUL 10 2015VALID 131200Z - 181200Z...DISCUSSION...ON MON/D4...AN UPPER RIDGE WILL REMAIN SITUATED ACROSS THE CNTRL ANDSRN PLAINS...WITH A BAND OF RELATIVELY STRONG NWLY FLOW ALOFT ACROSSTHE MID MS AND LOWER OH VALLEYS. IN THE SAME GENERAL VICINITY...ANONGOING MCS IS EXPECTED WITH PERHAPS A THREAT OF DAMAGING WINDS.OTHER CLUSTERS OF STORMS MAY BE ONGOING AS WELL FARTHER E ACROSSOH...KY AND WV IN A ZONE OF WARM ADVECTION ON THE NOSE OF A WLYLOW-LEVEL JET.LATER IN THE DAY...EXTREME INSTABILITY IS FORECAST TO REDEVELOPACROSS MUCH OF THE MIDWEST...BENEATH THIS FAVORABLE NW FLOW ALOFT.ALTHOUGH THE EXACT CORRIDOR IS DIFFICULT TO PREDICT AT THIS TIME DUETO COMPLEXITIES ASSOCIATED WITH OUTFLOW BOUNDARIES...NEW STORMDEVELOPMENT IS AGAIN LIKELY MONDAY EVENING NEAR THE MS RIVER ORACROSS CNTRL IL...AND EXTENDING SEWD ACROSS KY AND TN. DAMAGINGWINDS WILL AGAIN BE THE MAIN THREAT WITH ANY FORWARD PROPAGATINGSEVERE MCS. ALTHOUGH HIGHER-END WIND DAMAGE POTENTIAL MAYEXIST...PREDICTABILITY ISSUES CURRENTLY PRECLUDE ANY HIGHER SEVEREWEATHER PROBABILITIES. Link to comment Share on other sites More sharing options...
ClicheVortex2014 Posted July 10, 2015 Share Posted July 10, 2015 12z NAM... oh, God Link to comment Share on other sites More sharing options...
Hoosier Posted July 10, 2015 Share Posted July 10, 2015 12z 4km NAM is a legit emergency level scenario for DVN's CWA With a bullseye of 24", I'd say so. What is it with that model and qpf bombs? Link to comment Share on other sites More sharing options...
Chargers09 Posted July 10, 2015 Share Posted July 10, 2015 Partially interested in this event, though we know how these fronts end up south of modeled a lot of the time. We'll see where things end up, I suppose. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.