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Largest Svr Warn Box, ever...


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Go.... :huh:

credit foster for the graphic (1/5 of TN)

post-382-0-93475500-1329957643.png

BULLETIN - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WARNING

NATIONAL WEATHER SERVICE MORRISTOWN TN

555 PM EST WED FEB 22 2012

THE NATIONAL WEATHER SERVICE IN MORRISTOWN HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

ANDERSON COUNTY IN EAST TENNESSEE...

BLEDSOE COUNTY IN EAST TENNESSEE...

BLOUNT COUNTY IN EAST TENNESSEE...

NORTHERN BRADLEY COUNTY IN EAST TENNESSEE...

SOUTHERN CAMPBELL COUNTY IN EAST TENNESSEE...

CARTER COUNTY IN EAST TENNESSEE...

CLAIBORNE COUNTY IN EAST TENNESSEE...

COCKE COUNTY IN EAST TENNESSEE...

GRAINGER COUNTY IN EAST TENNESSEE...

GREENE COUNTY IN EAST TENNESSEE...

HAMBLEN COUNTY IN EAST TENNESSEE...

HAMILTON COUNTY IN EAST TENNESSEE...

HANCOCK COUNTY IN EAST TENNESSEE...

HAWKINS COUNTY IN EAST TENNESSEE...

JEFFERSON COUNTY IN EAST TENNESSEE...

KNOX COUNTY IN EAST TENNESSEE...

LOUDON COUNTY IN EAST TENNESSEE...

MCMINN COUNTY IN EAST TENNESSEE...

MEIGS COUNTY IN EAST TENNESSEE...

MONROE COUNTY IN EAST TENNESSEE...

MORGAN COUNTY IN EAST TENNESSEE...

RHEA COUNTY IN EAST TENNESSEE...

ROANE COUNTY IN EAST TENNESSEE...

EXTREME SOUTHERN SCOTT COUNTY IN EAST TENNESSEE...

SEQUATCHIE COUNTY IN EAST TENNESSEE...

SEVIER COUNTY IN EAST TENNESSEE...

EXTREME WESTERN SULLIVAN COUNTY IN EAST TENNESSEE...

UNICOI COUNTY IN EAST TENNESSEE...

UNION COUNTY IN EAST TENNESSEE...

WASHINGTON COUNTY IN EAST TENNESSEE...

* UNTIL 645 PM EST/545 PM CST/

* AT 546 PM EST/446 PM CST/...NATIONAL WEATHER SERVICE DOPPLER RADAR

INDICATED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING GOLF

BALL SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THESE

STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 7 MILES NORTHEAST

OF SNEEDVILLE TO 8 MILES NORTH OF MCMINNVILLE...AND MOVING EAST AT

65 MPH.

* LOCATIONS IN THE WARNING INCLUDE...

MAYNARDVILLE...RUTLEDGE...ROGERSVILLE...CLINTON...ROCKWOOD...OAK

RIDGE...MORRISTOWN...KINGSTON...JEFFERSON CITY...PIKEVILLE...

KNOXVILLE...JOHNSON CITY...LENOIR CITY...DANDRIDGE...DAYTON...

LOUDON...GREENEVILLE...ELIZABETHTON...ALCOA AND SEVIERVILLE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO

GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS

IMMEDIATELY! LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.

REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE

STRUCK BY LIGHTNING.

MD late on arrival into MRX

post-382-0-43710000-1329957528.gif

MESOSCALE DISCUSSION 0143

NWS STORM PREDICTION CENTER NORMAN OK

0549 PM CST WED FEB 22 2012

AREAS AFFECTED...NE AL...SE TN...FAR NW AL

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 222349Z - 230115Z

AN ISOLATED SEVERE THREAT WILL LIKELY INCREASE SOME OVER THE NEXT

FEW HOURS FROM MIDDLE TO ERN TN SWD ACROSS NRN AL AND FAR NW GA.

HAIL AND WIND DAMAGE WILL BE POSSIBLE. WW ISSUANCE MAY BE NECESSARY

ACROSS THE REGION.

A LINE OF STRONG THUNDERSTORMS IS ONGOING ALONG AN AXIS OF

INSTABILITY WHERE MESOANALYSIS SHOWS MUCAPE VALUES FROM 250 TO 750

J/KG. THE STORMS ARE DEVELOPING IN A STRONGLY SHEARED ENVIRONMENT

WITH WSR-88D-VWPS SHOWING 0-6 KM SHEAR VALUES OF 70 TO 80 KT. THIS

COMBINED WITH INCREASING LARGE-SCALE ASCENT AS A SHORTWAVE TROUGH

APPROACHES FROM THE WEST AND STEEP MID-LEVEL LAPSE RATES OF 7.0 TO

7.5 C/KM SHOULD BE SUFFICIENT FOR A HAIL THREAT WITH THE STRONGER

CORES EMBEDDED IN THE LINE. EWD STORM MOTION OF 40 KT WILL HELP

CREATE A WIND DAMAGE THREAT ESPECIALLY AS THE LINE BECOMES NEARLY

CONTINUOUS. SUPERCELLS WITH AN ISOLATED TORNADO THREAT MAY ALSO

EXIST ON THE SRN END OF THE LINE WHERE INSTABILITY IS MAXIMIZED AND

THE LOW-LEVEL JET IS FORECAST TO STRENGTHEN EARLY THIS EVENING.

..BROYLES.. 02/22/2012

ATTN...WFO...MRX...FFC...OHX...BMX...HUN...

LAT...LON 35928438 36378455 36558536 35888624 34918734 34258779

33898760 33648692 33748625 34138579 34718521 35348467

35928438

SE Thread pertaining... http://www.americanw...ad/page__st__35

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Not as large as the hebert box, all kidding aside. SPC probably doesn't want another Joplin, MO event to happen.

You do realize that the local WFOs issue the warnings, right? The Storm Prediction Center only issues convective/fire weather outlooks and convective watches.

On the topic of Joplin, when you can tell me what ingredients came together to produce that supercell, not to mention that specific tornado, you can talk about it. I could try to explain it all to you, but I'm almost at the raging point where I call you an idiot for saying "SPC probably doesn't want another Joplin, MO event to happen." That's just a BS statement.

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That would have been frustrating for the local media to cover, especially when there was little to no storm activity in the warning box area for the hour long duration and the warning called for "golf ball size hail".

They also issued two 13 county polygons. One was even for destructive 80 mph winds just before 8pm.

I'm less curious about the size of these warnings, but more about why they were issued in the first place. They weren't canceled or anything, just left to expire. After starting off with huge polygons with nothing in them they transferred over to smaller polygons on seemingly non-severe cells.

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They also issued two 13 county polygons. One was even for destructive 80 mph winds just before 8pm.

I'm less curious about the size of these warnings, but more about why they were issued in the first place. They weren't canceled or anything, just left to expire. After starting off with huge polygons they transferred over to smaller polygons on seemingly non-severe cells.

I've heard that the region regulations state that no more then 12 counties can be included in any given convective warning. Based on how much attention I've seen this get on Facebook, including an SPC meteorologist, I expect that someone will be getting a phone call from their region HQ.

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I've heard that the region regulations state that no more then 12 counties can be included in any given convective warning. Based on how much attention I've seen this get on Facebook, including an SPC meteorologist, I expect that someone will be getting a phone call from their region HQ.

I hope I can say this, but my immediate impression was they were being spiteful, or purposely acting negligent. If this were ever the case, what kind of protocol is in place? Obviously it would be noticed or tracked internally. I'd expect something like office duties being taken over by another office or another forecaster immediately canceling active warnings.

Just my own speculations...

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I hope I can say this, but my immediate impression was they were being spiteful, or purposely acting negligent. If this were ever the case, what kind of protocol is in place? Obviously it would be noticed or tracked internally. I'd expect something like office duties being taken over by another office or another forecaster immediately canceling active warnings.

Just my own speculations...

Yeah it could be a whacked out radar forecaster, the janitor, a rookie, MIC, or perhaps MRX has decided to start issuing county warning area based warnings now. Who knows?

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I'm sorry, the humor was a bit dry. It was mostly a bullsh** post but alot of NWS offices seem eager to blow the whistle for thundershowers. Sorry if I offended anyone, right; nobody wants another Joplin, MO.

It's okay. Just remember people are watching you and other people are watching them.

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Here's the largest polygon of the VTEC era. 39,716.5 sq km.

http://mesonet.agron...0R-200907090155

Despite that polygons size, there was a legitimate line of storms associated with that warning polygon. The low population of that region probably also prompted the larger than normal area. Sure it probably should have been smaller still, but I'm willing to let that slide as opposed to what we witnessed earlier this evening.

In tonights 30 county warning there was one small storm, not a line, that fit SVR criteria. The biggest problem is that its easy to get away with larger sizes, especially when that likely will improve upon verification scores. Perhaps there should be a new metric that includes polygon size into the verification metric. For example, let polygon verification scores also try to account for areal extent and population density of the given polygon rather than just checking off a box when two reports of fallen trees / large hail are reported. That would probably help keep those extra large warning polygon boxes in check.

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Despite that polygons size, there was a legitimate line of storms associated with that warning polygon. The low population of that region probably also prompted the larger than normal area. Sure it probably should have been smaller still, but I'm willing to let that slide as opposed to what we witnessed earlier this evening.

In tonights 30 county warning there was one small storm, not a line, that fit SVR criteria. The biggest problem is that its easy to get away with larger sizes, especially when that likely will improve upon verification scores. Perhaps there should be a new metric that includes polygon size into the verification metric. For example, let polygon verification scores also try to account for areal extent and population density of the given polygon rather than just checking off a box when two reports of fallen trees / large hail are reported. That would probably help keep those extra large warning polygon boxes in check.

The warning was basically for a non-existent line. And so were most following warnings. There wasn't really an initial first storm, just a mess of scattered low end dbz that developed a couple pockets of 50dbz around Knoxville throughout the first warning. No reports for even 0.25" hail surfaced from the first warnings. By the time the line actually arrived at the CWA border they put up more large warnings that expired by the time the line was entering the polygons.

post-277-0-18397300-1329978408.png

* AT 546 PM EST/446 PM CST/...NATIONAL WEATHER SERVICE DOPPLER RADAR

INDICATED A LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING GOLF

BALL SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THESE

STORMS WERE LOCATED ALONG A LINE EXTENDING FROM 7 MILES NORTHEAST

OF SNEEDVILLE TO 8 MILES NORTH OF MCMINNVILLE...AND MOVING EAST AT

65 MPH.

AT 615 PM EST/515 PM CST/...NATIONAL WEATHER SERVICE DOPPLER RADAR

CONTINUED TO INDICATE A LINE OF SEVERE THUNDERSTORMS CAPABLE OF

PRODUCING GOLF BALL SIZE HAIL...AND DAMAGING WINDS IN EXCESS OF 60

MPH. THESE STORMS WERE LOCATED ALONG A LINE EXTENDING FROM FALL

BRANCH TO MOUNT CREST...OR ALONG A LINE EXTENDING FROM 9 MILES SOUTH

OF KINGSPORT TO PIKEVILLE...MOVING EAST AT 60 MPH.

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Despite that polygons size, there was a legitimate line of storms associated with that warning polygon. The low population of that region probably also prompted the larger than normal area. Sure it probably should have been smaller still, but I'm willing to let that slide as opposed to what we witnessed earlier this evening.

In tonights 30 county warning there was one small storm, not a line, that fit SVR criteria. The biggest problem is that its easy to get away with larger sizes, especially when that likely will improve upon verification scores. Perhaps there should be a new metric that includes polygon size into the verification metric. For example, let polygon verification scores also try to account for areal extent and population density of the given polygon rather than just checking off a box when two reports of fallen trees / large hail are reported. That would probably help keep those extra large warning polygon boxes in check.

Yeah I'm not trying to defend it. lol.

But on the other hand, I wasn't interrogating it either, so I don't know what the real time situ was like, strength or alignment of the cold pool, environ conds, etc.

Pop density is not a factor when issuing a warning, and it shouldn't be.

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Smallest Tornado Warning box ever??

Issued today by AKQ : 95 Sq.Km..

These types of scenarios are tough as the storm is tracking right along CWA boundaries (WFO's AKQ and PHI). WFO AKQ could not draw their polygon any farther north since it would be out of their CWA.

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These types of scenarios are tough as the storm is tracking right along CWA boundaries (WFO's AKQ and PHI). WFO AKQ could not draw their polygon any farther north since it would be out of their CWA.

Understood, but Mt. Holly did not issue a warning (of any kind) in response to AKQ's warning. Kind of made AKQ look silly with no intra-CWA continuity.

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Understood, but Mt. Holly did not issue a warning (of any kind) in response to AKQ's warning. Kind of made AKQ look silly with no intra-CWA continuity.

PHI issued an SVR at 414 PM and was valid during AKQ's neighboring tornado warning (issued at 423 PM). AKQ issued an SVR at 414 PM:

BULLETIN - EAS ACTIVATION REQUESTED

SEVERE THUNDERSTORM WARNING

NATIONAL WEATHER SERVICE MOUNT HOLLY NJ

414 PM EST FRI FEB 24 2012

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

SUSSEX COUNTY IN CENTRAL DELAWARE...

THIS INCLUDES THE CITY OF GEORGETOWN...

* UNTIL 445 PM EST

* AT 405 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A

SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND

DAMAGING WINDS IN EXCESS OF 60 MPH. THIS STORM WAS LOCATED NEAR

SEAFORD...OR 17 MILES WEST OF GEORGETOWN...AND MOVING EAST AT 65

MPH. ANOTHER STORM WILL MOVE INTO THE SOUTHWEST CORNER OF SUSSEX

COUNTY.

* THE SEVERE THUNDERSTORM WILL CONTINUE TO AFFECT CENTRAL AND

SOUTHERN SUSSEX COUNTY DELAWARE THROUGH 445 PM.

BULLETIN - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WARNING

NATIONAL WEATHER SERVICE WAKEFIELD VA

414 PM EST FRI FEB 24 2012

THE NATIONAL WEATHER SERVICE IN WAKEFIELD HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...

DORCHESTER COUNTY IN SOUTHEAST MARYLAND...

SOMERSET COUNTY IN SOUTHEAST MARYLAND...

WICOMICO COUNTY IN SOUTHEAST MARYLAND...

NORTHWESTERN WORCESTER COUNTY IN SOUTHEAST MARYLAND...

* UNTIL 500 PM EST

* AT 410 PM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A

LINE OF SEVERE THUNDERSTORMS CAPABLE OF PRODUCING QUARTER SIZE

HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH. THESE STORMS WERE

LOCATED ALONG A LINE EXTENDING FROM FEDERALSBURG TO NANTICOKE TO 8

MILES WEST OF BLOODSWORTH ISLAND...AND MOVING EAST AT 55 MPH.

BULLETIN - EAS ACTIVATION REQUESTED

TORNADO WARNING

NATIONAL WEATHER SERVICE WAKEFIELD VA

423 PM EST FRI FEB 24 2012

THE NATIONAL WEATHER SERVICE IN WAKEFIELD HAS ISSUED A

* TORNADO WARNING FOR...

NORTH CENTRAL WICOMICO COUNTY IN SOUTHEAST MARYLAND...

* UNTIL 445 PM EST

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I have zero knowledge of the situation (even though I am in TN), but going back to what foster said, I wonder if someone was a little unhappy SPC did not have a watch out for the area. Pure speculation of course...we may never know the real answer.

That would have been my guess also. Just seems a bit silly and doesn't help with respect to warning folks. I mean over half of those counties it probably didn't even rain let alone had any severe weather.

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That would have been my guess also. Just seems a bit silly and doesn't help with respect to warning folks. I mean over half of those counties it probably didn't even rain let alone had any severe weather.

Yeah it does. That's assuming much drama on the part of the warning forecaster. It assumes he/she was so emotionally distraught that SPC did not have a watch out (a nominal product) that they were willing to put their career on the line, their, their office's and the NWS's reputation on the line, and throw all responsibility to their oath of protecting life and property out the window. That's a big assumption. Silly really.

I have a feeling it was more to due with a misinterpretation of environ conds and expectations of that system due to previous mesoscale experiences, such as was pointed out in the chats.

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