Thundersnow12 Posted September 10, 2014 Share Posted September 10, 2014 925mb winds over eastern KS and into MO pushing 50kts currently. That will slowly move ENE overnight and the heaviest rain should stay on those of that. Link to comment Share on other sites More sharing options...
cyclone77 Posted September 10, 2014 Share Posted September 10, 2014 Deep convection festering closer to the better instability down in northern MO really saved eastern IA/northern IL from a significant rainfall event tonight. Most of the rains in this area have been pretty wimpy, with little to no thunder. Still haven't breached the inch mark here, and radar returns continue to decline. Just goes to show how unpredictable weather can be when dealing with convection. Link to comment Share on other sites More sharing options...
tornadotony Posted September 10, 2014 Share Posted September 10, 2014 An EMC WRF outcome would make my stance on tomorrow incorrect. Link to comment Share on other sites More sharing options...
Stebo Posted September 10, 2014 Share Posted September 10, 2014 An EMC WRF outcome would make my stance on tomorrow incorrect. Wow, that would be something if it were to be correct. Some pretty stout cells form on the warm front and cold front. Link to comment Share on other sites More sharing options...
tornadotony Posted September 10, 2014 Share Posted September 10, 2014 Wow, that would be something if it were to be correct. Some pretty stout cells form on the warm front and cold front. NMM and ARW from NCEP are similar. For now, I'm holding to my guns based on past experience, but to be honest, something doesn't feel right here. It's not comforting seeing the high res guidance tonight. Link to comment Share on other sites More sharing options...
chase_stormz Posted September 10, 2014 Share Posted September 10, 2014 An EMC WRF outcome would make my stance on tomorrow incorrect. Where can I view that? Or can a link be posted? Link to comment Share on other sites More sharing options...
Stebo Posted September 10, 2014 Share Posted September 10, 2014 NMM and ARW from NCEP are similar. For now, I'm holding to my guns based on past experience, but to be honest, something doesn't feel right here. It's not comforting seeing the high res guidance tonight. They seem to be handling the current convection very well. Link to comment Share on other sites More sharing options...
tornadotony Posted September 10, 2014 Share Posted September 10, 2014 They seem to be handling the current convection very well. Yes they are. And another point that is interesting to think about...the H5 T at TOP at 00z was -5°C...700-500 LR was only 6.2 K/km (and was only 5.9 K/km at 18z), but look at what happened out there. It's not going to get nearly as hot tomorrow, but the system is going to be somewhat stronger. I still don't like how quickly the low-level flow veers and I think it has a very distinct chance of quelling a majority of the severe threat, but given the good spinup these high res runs had this evening and what we've seen this evening, I'm not quite as comfortable with my position on tomorrow's threat as I have felt the last couple days. Link to comment Share on other sites More sharing options...
andyhb Posted September 10, 2014 Author Share Posted September 10, 2014 NMM and ARW from NCEP are similar. Add on the NSSL WRF to that. The UH sigs aren't super strong, but there's definitely enough discrete activity on it to give pause. Link to comment Share on other sites More sharing options...
tornadotony Posted September 10, 2014 Share Posted September 10, 2014 NSSL WRF also has numerous discrete to semi-discrete cells with good updraft helicity across ern IL, IN, and wrn OH tomorrow. Link to comment Share on other sites More sharing options...
andyhb Posted September 10, 2014 Author Share Posted September 10, 2014 lol There's a clear wind shift prior to FROPA on that particular model indicating a fairly stout pre-frontal trough. I would think it shows up on the others, but I haven't looked at those fields yet. Link to comment Share on other sites More sharing options...
Stebo Posted September 10, 2014 Share Posted September 10, 2014 Let me correct myself the stuff doesn't form on the cold front, it forms on a prefrontal trough, especially in Indiana Edit: Andy ninjaed us both... Link to comment Share on other sites More sharing options...
tornadotony Posted September 10, 2014 Share Posted September 10, 2014 Even the 00z GFS looks better to me for tomorrow across ern IL and into IN. The winds have a more regular veering with height, and the thermos even look decent despite the warm temps aloft. Link to comment Share on other sites More sharing options...
tornadotony Posted September 10, 2014 Share Posted September 10, 2014 To illustrate the change in my tune, let's compare forecast soundings from the GFS at 21z tomorrow at Crawfordsville, IN. The first one here is from the 12z GFS. Note the rapid/dramatic veering of flow in the low-level, a component to the hodograph that I've seen in several failed severe wx potential setups. This sort of veering is often associated with departing synoptic forcing (the lifting out of a low or trough) and can be accompanied with a lack of forcing for ascent. Now look at the hodo from the same location and time from the 00z GFS. This is a much more balanced hodo, with stronger low-level flow, not as "squashed" looking as the hodo from 12z, and actually looks pretty darn good in the low-levels, albeit slightly tilted from what you'd normally expect. What it tells me is that the forcing for ascent is more likely to stick around and support organized convection than I originally thought for tomorrow, and the high-res simulations certainly indicate that. I'm not all-in yet on this. I want to see how the overnight and morning convection really evolves, what happens to the synoptic system (how strong does it get and where does it track, etc.). But I think it's time for me to be open to the idea of a potential for an event more significant than I originally thought. Link to comment Share on other sites More sharing options...
Hoosier Posted September 10, 2014 Share Posted September 10, 2014 Day 1 outlook is out early. 2% tornado, 5% hail and 30% wind. Link to comment Share on other sites More sharing options...
Stebo Posted September 10, 2014 Share Posted September 10, 2014 Day 1 outlook is out early. 2% tornado, 5% hail and 30% wind. I guess they decided not to look at 00z model suite... Link to comment Share on other sites More sharing options...
Thunder Road Posted September 10, 2014 Share Posted September 10, 2014 over/unders running neck and neck I think I saw a 6.10" LSR go by from DMX earlier, so I'm feeling pretty good about my call. Link to comment Share on other sites More sharing options...
Chicago Storm Posted September 10, 2014 Share Posted September 10, 2014 I guess they decided not to look at 00z model suite...Na, it will be a non-event for most. Link to comment Share on other sites More sharing options...
andyhb Posted September 10, 2014 Author Share Posted September 10, 2014 I guess they decided not to look at 00z model suite... FORECAST SOUNDINGS ACROSS THE WARM SECTOR AT 00Z/THURSDAY FOR INDIANAPOLIS INDIANA AND ST LOUIS MO SHOW MLCAPE IN THE 1200 TO 2000 J/KG RANGE WITH SFC DEWPOINTS IN THE LOWER 70S F. THIS COMBINED WITH UNIDIRECTIONAL WINDS AND AMPLE SPEED SHEAR IN THE MID-LEVELS SHOULD BE FAVORABLE FOR SQUALL-LINE DEVELOPMENT. Link to comment Share on other sites More sharing options...
tornadotony Posted September 10, 2014 Share Posted September 10, 2014 I guess they decided not to look at 00z model suite... I wouldn't do much differently yet despite what I've posted above. Overnight evolution is going to be really key to anything, and despite the models appearing to handle it well so far, I don't trust them. If I were to make any sort of changes, I would probably just expand the 2% tornado risk east and northeastward and MAYBE add a 5% risk in central IN, but they can always do that at 1300 UTC if convective trends appear on track with the high-res guidance. Link to comment Share on other sites More sharing options...
Hoosier Posted September 10, 2014 Share Posted September 10, 2014 I guess they decided not to look at 00z model suite... I don't think it's that unreasonable at this point. I was thinking they would go 5% tornado but other than that the probs seem fine given the lingering uncertainties. Link to comment Share on other sites More sharing options...
Stebo Posted September 10, 2014 Share Posted September 10, 2014 I wouldn't do much differently yet despite what I've posted above. Overnight evolution is going to be really key to anything, and despite the models appearing to handle it well so far, I don't trust them. If I were to make any sort of changes, I would probably just expand the 2% tornado risk east and northeastward and MAYBE add a 5% risk in central IN, but they can always do that at 1300 UTC if convective trends appear on track with the high-res guidance. Good point, I did kind of shoot from the hip there with my post. Link to comment Share on other sites More sharing options...
Hoosier Posted September 10, 2014 Share Posted September 10, 2014 Na, it will be a non-event for most. That's pretty ambiguous as many severe weather events are non-events for most. Any guess on number of severe reports? Link to comment Share on other sites More sharing options...
tornadotony Posted September 10, 2014 Share Posted September 10, 2014 That's pretty ambiguous as many severe weather events are non-events for most. Any guess on number of severe reports? I'm gonna go 35 wind reports and 1 tornado report within the slight risk area for now, just for kicks and giggles. Link to comment Share on other sites More sharing options...
Stebo Posted September 10, 2014 Share Posted September 10, 2014 I'm gonna go 35 wind reports and 1 tornado report for now, just for kicks and giggles. Yeah my initial guess was going to be like 40/3. Link to comment Share on other sites More sharing options...
A-L-E-K Posted September 10, 2014 Share Posted September 10, 2014 Heavy rain is delivering Link to comment Share on other sites More sharing options...
Chicago WX Posted September 10, 2014 Share Posted September 10, 2014 Some big totals from western IL and northeast MO. 0630 AM HEAVY RAIN 4 NE RUSHVILLE 40.16N 90.51W09/10/2014 M6.96 INCH SCHUYLER IL CO-OP OBSERVER 0600 AM HEAVY RAIN EDINA 40.17N 92.17W09/10/2014 M7.26 INCH KNOX MO CO-OP OBSERVER 0556 AM HEAVY RAIN LEWISTOWN 40.08N 91.81W09/10/2014 M8.10 INCH LEWIS MO EMERGENCY MNGR 0415 AM HEAVY RAIN 7 N PARIS 39.58N 92.00W09/10/2014 M6.48 INCH MONROE MO MESONET Link to comment Share on other sites More sharing options...
cyclone77 Posted September 10, 2014 Share Posted September 10, 2014 Once severe storms in Missouri shut down the more stratiform rains to the north took off with the LLJ kicking up. Picked up 2.02" after midnight for a two day total of 3.02". Link to comment Share on other sites More sharing options...
hawkeye_wx Posted September 10, 2014 Share Posted September 10, 2014 The strong convection down south cut off the moisture transport into the northern half of Iowa, so the system was a big bust for some. I don't think there was even one rumble of thunder here. A long-duration light to moderate rain was able to drop 1.19" in my yard overnight, a far cry from what we could've received, but still my best rain in two months. My two-day total is 2.18". Link to comment Share on other sites More sharing options...
Chicago WX Posted September 10, 2014 Share Posted September 10, 2014 Never high hopes for here...and the rainfall will turn out to be pretty meh in the LAF. Newest day one outlook trims some off the western edges. DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 0756 AM CDT WED SEP 10 2014 VALID 101300Z - 111200Z ...THERE IS A SLGT RISK OF SVR TSTMS SRN GREAT LAKES REGION TO MO OZARKS... ..SUMMARY SCATTERED TO NUMEROUS THUNDERSTORMS...SOME SEVERE...ARE EXPECTED TO DEVELOP NEAR A COLD FRONT FROM THE SOUTHERN GREAT LAKES REGION SOUTHWESTWARD INTO THE MID MISSISSIPPI VALLEY AND OZARKS. DAMAGING WINDS WILL BE THE PRIMARY THREAT THIS AFTERNOON AND EARLY EVENING. ..SYNOPSIS BROADLY CYCLONIC FLOW WILL CHARACTERIZE MID-UPPER-LEVEL PATTERN OVER ROUGHLY NRN 1/2 OF CONUS THROUGH PERIOD. EMBEDDED WITHIN THAT...SHORTWAVE TROUGH NOW OVER PORTIONS MN/IA/NEB WILL MOVE ENEWD TO ERN LS...ERN UPPER MI AND NRN LM BY 00Z. THIS FEATURE SHOULD CROSS QUE/ONT BORDER REGION S OF JAMES BAY NEAR END OF PERIOD...LEADING A NARROW/WEAK 500-MB VORTICITY RIBBON AS FAR SWWD AS NRN OK...CENTRAL NM AND SRN AZ. UPSTREAM PERTURBATION CURRENTLY OVER WRN MT...AND AHEAD OF MUCH STRONGER CANADIAN TROUGH -- WILL MOVE EWD ACROSS NRN HIGH PLAINS TODAY...REACHING NRN MN OVERNIGHT. STRONGEST SHORTWAVE PERTURBATION -- NOW EVIDENT IN MOISTURE-CHANNEL IMAGERY OVER CANADIAN ROCKIES OF SERN BC/SWRN AB -- WILL MOVE SEWD ACROSS WRN MT AND NRN ID THROUGH 12Z. AT SFC...11Z ANALYSIS SHOWED PRIMARY CYCLONE OVER ERN IA. ASSOCIATED LOW WILL DEEPEN AND MOVE NEWD ALONG SYNOPTIC-SCALE BAROCLINIC ZONE...REACHING NRN LOWER MI BY 00Z AND CROSSING QUE/ONT BORDER DURING 06-12Z TIME FRAME. TRAILING COLD FRONT -- ANALYZED FROM IA LOW SWWD ACROSS NWRN MO...ERN KS...NWRN OK AND SRN PANHANDLE OF TX -- SHOULD REACH NWRN INDIANA...ERN MO...SERN OK AND SERN NM BY 00Z. AT END OF PERIOD...FRONT SHOULD LIE NEAR BUF...CMH...DYR...SEP...INK LINE. ..SRN GREAT LAKES REGION TO MO OZARKS TWO OR MORE PRIMARY BANDS OF TSTMS SHOULD MOVE EWD ACROSS AREAS FROM ERN MO TO OH TODAY...ALONG AND AHEAD OF SFC COLD FRONT. ONE OF THESE STG-SVR CONVECTIVE EPISODES MAY BE ASSOCIATED WITH ZONE OF LOW-LEVEL LIFT RELATED TO ACTIVITY NOW CROSSING FROM MO INTO IL...MOVING/SPREADING ENEWD INTO DIURNALLY DESTABILIZING AND FAVORABLY MOIST AIR MASS ACROSS PORTIONS INDIANA...LOWER MI AND WRN/NRN OH. ADDITIONAL DEVELOPMENT IS POSSIBLE THIS AFTN OVER PARTS OF SRN/ERN MO AND CENTRAL/SRN IL...CLOSER TO COLD FRONT AND IN ZONE OF DESTABILIZATION BEHIND THINNEST PART OF MORNING CONVECTION. MAIN THREAT WILL BE DAMAGING GUSTS...ALTHOUGH SPORADIC HAIL MAY OCCUR AND A TORNADO CANNOT BE RULED OUT. FOREGOING AIR MASS WILL REMAIN CHARACTERIZED BY PW CLOSE TO 2 INCHES...MODEST MIDLEVEL LAPSE RATES...SFC DEW POINTS 60S TO LOW 70S F...AND PATCHES/SWATHS OF VARIABLY STG INSOLATION/HEATING. BECAUSE OF THOSE WEAK LAPSE RATES...ONLY ABOUT 800-1500 J/KG MLCAPE WILL DEVELOP IN MOST OF THIS CORRIDOR...LOCALLY NEAR 2000 J/KG WHERE HEATING IS MOST INTENSE/SUSTAINED. 30-40-KT EFFECTIVE-SHEAR MAGNITUDES AND ELONGATED LOW-LEVEL HODOGRAPHS ARE FCST...WITH ONLY MODEST DIRECTIONAL SHEAR DUE TO SWLY FLOW AHEAD OF BOTH FRONT AND CONVECTIVE BANDS. THIS WILL SUPPORT CONTINUED DOMINANCE OF QUASI-LINEAR CONVECTIVE MODE AND RESULTANT WEIGHT TOWARD DAMAGING WIND AS MAIN CONCERN. STILL...STRENGTH OF LLJ IS EXPECTED TO BE MAINTAINED AT 45-60 KT THROUGHOUT DAYLIGHT HOURS FROM ERN IL INTO PORTIONS LOWER MI AND OH...AS LOW-LEVEL CYCLONE DEEPENS TO ITS W AND NW. THIS WILL ELONGATE/ENLARGE LOW-LEVEL HODOGRAPHS AND OFFER AT LEAST MRGL/CONDITIONAL TORNADO POTENTIAL...STRONGLY DEPENDENT ON CONVECTIVE MODE. ONGOING CLOUD/PRECIP PLUME WIDENS NEWD...WITH LONGER PROJECTED TRAJECTORIES NEEDING TO PASS THROUGH CONVECTIVELY MODIFIED AIR IN PREFRONTAL SECTOR. AS SUCH...AIR MASS BEHIND THIS PLUME WILL BE LESS LIKELY TO DESTABILIZE SUBSTANTIALLY TODAY WITH NWD EXTENT...AND UNCONDITIONAL SVR PROBABILITIES ON NW RIM OF ORIGINAL OUTLOOK HAVE BEEN TRIMMED ACCORDINGLY. ..OZARKS TO RED RIVER REGION ALTHOUGH MIDLEVEL LAPSE RATES WILL INCREASE WITH SWWD EXTENT...SO WILL CAPPING AT BASE OF ASSOCIATED EML. FOR THIS REASON...CONVECTION INITIATION IS EXPECTED LATER OVER RED RIVER AREA THAN IN OZARKS...HOWEVER SCATTERED TSTMS SHOULD FORM NEAR FRONT BY 00Z. DEEP SHEAR AND MID-UPPER SUPPORT EACH WILL DIMINISH WITH SWWD EXTENT...AS WILL LOW-LEVEL CONVERGENCE. NONETHELESS...COMBINATION OF STRONGER SFC HEATING THAN FARTHER NE...AND AVAILABLE FRONTAL LIFT...SHOULD SUPPORT STRAND OF CONVECTION ATOP WELL-MIXED SUBCLOUD LAYER...AND ATTENDANT POTENTIAL FOR ISOLATED STG-SVR GUSTS AND WIND DAMAGE. INCREASING NEAR-SFC STATIC STABILITY AND MLCINH AFTER DARK WILL REDUCE THIS THREAT WITH TIME. ..EDWARDS/LEITMAN.. 09/10/2014 Link to comment Share on other sites More sharing options...
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