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Becoming more active into November


OKpowdah

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yeah a few quick ones. but it was generally lesser than many (not necessarily here) thought it would be. there are plenty of other ways to come to those conclusions without that graphic imo.

Yeah really got a "most significant tornado outbreak in the past few years over the Central US" with that one...

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It wasn't useless before they lowered the CAPE and raised the LCL thresholds. Now, sadly, it seems to be nearly useless. If it still required 1000 J/kg MLCAPE, I bet we'd be seeing 10% at best.

I'm really surprised by the amount of chatter in the chase community about tomorrow. Usually I'm one of the last to completely write something off, since I'm satisfied with decent structure even when tornado potential is nil. I will admit I have kind of a rigid mental threshold of 60 F for dew points when dealing with anything east of the High Plains. Only on a very few occasions have I seen exceptions (8 Mar 2010 in W OK being the only one coming to mind at the moment).

What really bothers me is the combination of low buoyancy and a narrow instability axis with extreme deep-layer shear. Estimated storm motion on most forecast soundings tomorrow is in the ballpark of 55 kt. That gives you under two hours before an incipient updraft near the dryline/front begins leaving what little instability we'll have. Also, it sometimes seems to take supercells longer to mature when facing an environment characterized by a 100+ kt jet streak in the vicinity.

All that said, this is probably the best-looking LLJ we've seen on the Plains since April 14, being out of the south at 45-55 kt. NAM soundings for areas like PTT-RSL at 00z look almost doable, if not for the cap at the bottom of the EML. I'd be rather shocked to see any red dots on the reports map tomorrow night, but there will probably be quite a few green ones on SN, and I just might be one.

I guess tomorrow is a good way to gauge how much the Kansas State Police still dislike chasers after all these months. :P

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It wasn't useless before they lowered the CAPE and raised the LCL thresholds. Now, sadly, it seems to be nearly useless. If it still required 1000 J/kg MLCAPE, I bet we'd be seeing 10% at best.

I'm really surprised by the amount of chatter in the chase community about tomorrow. Usually I'm one of the last to completely write something off, since I'm satisfied with decent structure even when tornado potential is nil. I will admit I have kind of a rigid mental threshold of 60 F for dew points when dealing with anything east of the High Plains. Only on a very few occasions have I seen exceptions (8 Mar 2010 in W OK being the only one coming to mind at the moment).

What really bothers me is the combination of low buoyancy and a narrow instability axis with extreme deep-layer shear. Estimated storm motion on most forecast soundings tomorrow is in the ballpark of 55 kt. That gives you under two hours before an incipient updraft near the dryline/front begins leaving what little instability we'll have. Also, it sometimes seems to take supercells longer to mature when facing an environment characterized by a 100+ kt jet streak in the vicinity.

All that said, this is probably the best-looking LLJ we've seen on the Plains since April 14, being out of the south at 45-55 kt. NAM soundings for areas like PTT-RSL at 00z look almost doable, if not for the cap at the bottom of the EML. I'd be rather shocked to see any red dots on the reports map tomorrow night, but there will probably be quite a few green ones on SN, and I just might be one.

I agree it used to be a good tool. It may still be but it clearly doesn't work the same as it used to. Not trying to say don't look at it but I see people like Timmer talking up strong tornadoes across the region when sharing it. Obviously he's doing the usual thing so I shouldn't use him as a gauge. I agree otherwise, as usual.

excuse bad grammar: had a drink too many this eve... :whistle:

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I agree it used to be a good tool. It may still be but it clearly doesn't work the same as it used to. Not trying to say don't look at it but I see people like Timmer talking up strong tornadoes across the region when sharing it. Obviously he's doing the usual thing so I shouldn't use him as a gauge. I agree otherwise, as usual.

I bet he doesn't realize the ingredients have changed, and the same can be said for the majority of its users. Not that it would stop him if he did know ;), but for such a major alteration to the formula, it's almost impossible to spot unless you see the talk about it here, on FB, etc. I do think that in the past, a 50% bullseye on that chart usually meant business. So cruel to chasers... it's the equivalent of quietly multiplying NAM/GFS snow output by a factor of 4 for the weenies in your hood.

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D1:

DAY 1 CONVECTIVE OUTLOOK

NWS STORM PREDICTION CENTER NORMAN OK

1159 PM CST FRI NOV 09 2012

VALID 101200Z - 111200Z

...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF THE PLAINS

STATES/CENTRAL U.S....

..SYNOPSIS

A LARGE UPPER TROUGH OVER THE WRN U.S. IS PROGGED TO ADVANCE SLOWLY

EWD THIS PERIOD...INCREASINGLY AFFECTING THE CENTRAL THIRD OF THE

CONUS. AS THIS TROUGH SHIFTS EWD...A SURFACE LOW INITIALLY INVOF CO

SHOULD CONSOLIDATE AND SHIFT QUICKLY NEWD WITH TIME...REACHING THE

U.S./CANADIAN BORDER INVOF NRN MN LATE. AS THIS OCCURS...A WARM

FRONT WILL LIFT NWD ACROSS THE GREAT LAKES REGION...WHILE A STRONG

COLD FRONT DRIVES EWD/SEWD ACROSS THE PLAINS STATES THROUGH THE

PERIOD. THIS FRONT WILL FOCUS SHOWERS AND THUNDERSTORMS -- AND SOME

SEVERE POTENTIAL -- DURING THE AFTERNOON AND EVENING HOURS.

..UPPER MS/MID MO VALLEYS SSWWD INTO NWRN TX

RATHER COMPLICATED SCENARIO IS UNFOLDING ACROSS THE CENTRAL U.S.

AHEAD OF THE LARGE/ADVANCING WRN TROUGH...AS VERY STRONG FLOW ALOFT

SUGGESTS SEVERE POTENTIAL...WHILE AN ONLY MODESTLY

UNSTABLE/LIKELY-TO-BE-CAPPED WARM SECTOR WILL LIKELY TEND TO HINDER

OVERALL SEVERE POTENTIAL.

ATTM...IT APPEARS THAT INITIAL STORM DEVELOPMENT INVOF A PRE-FRONTAL

TROUGH/DRYLINE SHOULD OCCUR IN THE 22-23Z TIME FRAME INVOF WRN KS

AND ERN PORTIONS OF THE TX/OK PANHANDLES...AS AFTERNOON HEATING

PERMITS DEVELOPMENT OF 500 TO 1000 J/KG MIXED-LAYER CAPE. GIVEN

CAPPING LIKELY TO BE PRESENT...INITIAL DEVELOPMENT IS LIKELY TO BE

ISOLATED...AND THUS -- GIVEN BACKGROUND FLOW FIELD -- LIKELY

SUPERCELLULAR. ALONG WITH POTENTIAL FOR HAIL...LOCALLY DAMAGING

WINDS WILL ALSO BE POSSIBLE.

WITH TIME...STORMS SHOULD EXPAND NNEWD ALONG THE COLD FRONT AS IT

ADVANCES ACROSS THE MID MO VALLEY REGION -- AND PERHAPS NWD INTO MN

THOUGH INSTABILITY SHOULD DIMINISH WITH NWD EXTENT. WITH

TIME...STORMS SHOULD EVOLVE TOWARD A FORCED LINEAR MODE INVOF THE

FRONT -- PARTICULARLY FROM NRN KS NWD...WITH POTENTIAL FOR LOCALLY

DAMAGING WINDS AND MARGINAL HAIL EXPECTED. FARTHER S INTO

KS/OK...STORMS MAY REMAIN MIXED IN MODE -- WITH SOME CELLULAR

CONVECTION POSSIBLY LINGERING THROUGH THE EVENING UNTIL A MORE

LINEAR CONVECTIVE MODE EVOLVES LATE AS THE COLD FRONT DRIVES ACROSS

THIS REGION. GENERALLY...EXPECT STORM INTENSITY -- AND ASSOCIATED

SEVERE POTENTIAL -- TO DIMINISH SLOWLY FROM LATE EVENING ONWARD.

..GOSS/GARNER.. 11/10/2012

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My hunch is tomorrow will be the better day for any severe potential from the Piney Woods of E Texas on NE in Arkansas. That said it appears that capping will remain strong further S and any discrete activity will be limited. This appears to be a linear threat more than anything, IMO.

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I'm a little more optimistic about south/southeastern NE for severe potential (versus areas further south)... colder mid-level temps, wider instability axis, closer to surface low/more low-level backing.

I whole-heartedly agree with this. Taking a closer look (finally) at the setup, I don't really see much tornado potential south of maybe Salina. I just don't think the moisture return will allow it. Supercells? Maybe.

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New outlook expanded the 5% tornado quite a bit and increased hail to 30%. Wording is a bit stronger too.

MODEL CONSENSUS INDICATES THAT FORCING FOR

ASCENT WILL BE SUFFICIENT TO WEAKEN THE CAP WITH DISCRETE STORMS

DEVELOPING FROM EXTREME WRN OK ACROSS CENTRAL KS INTO SOUTH

CENTRAL/SERN NEB. STRONG LOW LEVEL AND DEEP LAYER SHEAR WILL

PROMOTE DEVELOPMENT OF INITIAL SUPERCELL STRUCTURES WITH A THREAT

FOR LARGE HAIL...DAMAGING WINDS...AND A FEW TORNADOES. STORMS ARE

EXPECTED TO MOVE RAPIDLY NEWD THROUGH THE EVENING HOURS WITH

CONTINUED SEVERE POTENTIAL...WITH SOME CONVECTION-ALLOWING MODELS

INDICATING SUPERCELL AND BOW ECHO STORM ACTIVITY. WITH

TIME...STORMS ARE EXPECTED TO TRANSITION TO LINEAR SEGMENTS WITH

SEVERE WINDS BECOMING THE PRIMARY THREAT DURING THE NIGHT.

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MD out for C KS north through C-SE NE mentioning discrete thunderstorms and supercells possibly by 21-23z with the main threat being hail and wind with a possibility of isolated tornadoes. Looks to be discrete mode initially and then more of a messy mode. I guess I'll dust off Analyst and keep an eye on it this evening.

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Hmm. Can't say I was expecting this.

TORNADO WATCH OUTLINE UPDATE FOR WT 676

NWS STORM PREDICTION CENTER NORMAN OK

1255 PM CST SUN NOV 11 2012

TORNADO WATCH 676 IS IN EFFECT UNTIL 700 PM CST FOR THE

FOLLOWING LOCATIONS

TXC001-037-063-067-073-159-161-183-203-213-223-289-315-343-347-

365-379-387-401-419-423-449-459-467-499-120100-

/O.NEW.KWNS.TO.A.0676.121111T1855Z-121112T0100Z/

TX

. TEXAS COUNTIES INCLUDED ARE

ANDERSON BOWIE CAMP

CASS CHEROKEE FRANKLIN

FREESTONE GREGG HARRISON

HENDERSON HOPKINS LEON

MARION MORRIS NACOGDOCHES

PANOLA RAINS RED RIVER

RUSK SHELBY SMITH

TITUS UPSHUR VAN ZANDT

WOOD

$$

ATTN...WFO...LZK...SHV...FWD...

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