Accessory cloud - What all the best dressed thunderstorms will have this year.  Supercells, the jet-set of the thunderstorm classes, usually dress themselves with a variety of accessory clouds.

Anvil crawlers- Cloud motion in the storm's anvil which demonstrates that it is going through its infant stage.

Anvil dome-An area of bald clouds pushing up through the thunderstorm's anvil, the smooth structure of these clouds show it has reaching its maturity possibly with an overabundance of updraft leading to the loss of control over its storm top.

Anvil rollover - A measure of the strength of thunderstorm straight-line winds.  This refers to a wind speed sufficient to tumble a standard blacksmith's anvil along the ground for a minimum of one full revolution.  Most likely, the term originated during the days of the old west.

Anvil zits- Structures on the underside of a thunderstorm's anvil cloud that when illuminated by lightning demonstrate that the storm is going through its adolescent stage.

Arcus - Arcing among us. [Slang], the electrical discharge of a lightning strike spreading among a group of people caught out in the open during a thunderstorm.  Spotters should make every attempt to avoid becoming part of an arcus.

Auntie-cyclonic rotation - What Dorothy saw from the storm cellar as Auntie Em and the new farmhouse were sucked up by a large tornado several years after Dorothy's trip to Oz.

Bear's cage - [Slang], area of rain-wrapped mesocyclone featuring low-visibility and high fatality.  Should only be entered by TV weather vehicles, storm chasers and other expendable types.  Check your life insurance policy before entering, the 'bear' may want you to stay for supper!

Barber pole - In the days before doctors became widely available, barbers often also served as physicians.  It may be that the injuries caused by supercells led to the association of the vertical striations on the main storm towers with the need for the medical care provided by the barber.

Beaver's tail - A low, flat type of inflow band, predominately seen with HP Supercells.  The term probably came from storms showing this feature having the tendency to flatten the local area like it was hit by a giant "beaver's tail."

BWER - (Pronounced b-were)  Garbled transmission (warning?) often heard from someone who's just entered the Bear's cage.  It's likely a form of 'beware' but may be a reference to the 'bear' being home.  No one has yet to survive to explain the term.

Cap - A non-technical method of determining the strength of a thunderstorm updraft.  By standing under the updraft while wearing some type of cap, the wearer measures the updraft speed and strength by allowing the winds to carry the cap up into the storm.  Rapid vertical motion of the cap, with rotation in counter-clockwise motion may denote the presence of a low-level mesocyclone.  If the wearer as well as the cap is drawn up in a spiral pattern, counterclockwise, then a tornado is likely to be present.
 Note:  Other objects can often be used for this as well as caps.  For instance see Auntie-cyclonic rotation.

 Classic supercell - These are the most normal of the three thunderstorm elite.  While everything revolves around them, they still retain the basic structure of their roots.  Their accessory clouds are where one expects them to be in a tastefully decorated storm.  They usually allow good visibility as to their activities, with major features visible from the proper viewing angles.  While quite dangerous and prone to become angry and smite the ground with heavy precip and hail, they at least are more open about their dropping of tornadoes.
 One should note, that on occasion the classic can develop behavioral problems which may lead them to take on HP characteristics, and the resulting mysterious behavior.  Likewise on occasion, an HP will come to its 'senses' and act more socially acceptable and become more like a classical supercell.

Cloud seeding - The process of attempting to produce rain from clouds by 'seeding' or dropping certain chemicals or dry ice from airplanes into the clouds hoping to cause the formation of water droplets large enough to fall out of the cloud.
 Note:  An early attempt may have involved dropping pieces of laxatives ( you know, like Ex-Lax)  into the clouds but may have resulted in such terrible flash-flooding that the perpetrators were dragged out into the streets by the flood survivors and shot down like dogs.  Several cases of a laxative were reported missing from a warehouse in the upper midwest a few years ago, shortly before the disastrous flooding along the upper Mississippi and parts of the Missouri.  Nothing was ever proved, but a few people are still listed as missing.

Convergence - The contraction of the area occupied by mobile weather observers usually indicating pending severe weather, a total lack of severe development on an anticipated severe day, a free wireless internet access point, cheap travel food, etc.  The level of convergence may indicate the coverage of anticipated severe weather.  A tight convergence will usually mean a single severe event for the area (or a single source of the non-weather attracters) while a broader area of convergence usually happens when the severe threat covers a wide area.

Cyclic storm - Storms that either liked what they just did so much that they want to do it again and again, or ones that can't remember their own history and are doomed to keep repeating it.  With supercells this can be quite a problem, especially when they get carried away.

Debris cloud - Tornadoes tend to pick up much more than they can actually carry, and will just swirl it around for a while until they decide the best place to drop things.  Unfortunately, tornadoes are very hard on the things they decide to play with and most will not be of any value after the tornado is done with them.  Once the tornado has picked something up and damaged it, it goes from whatever it had been to 'debris', and the tornado carries it around and around like a cloud surrounding the base of the tornado, therefore the term 'debris cloud' was developed.  Once the tornado has tired and dropped its playthings back to earth, the now useless material becomes 'debris piles' or more often is just called 'damage'.
 It is incorrect to use this term to describe a group of storm chasers or sight-seers which surround severe thunderstorm, though such use persists.

Dew point (or Dew point temperature) - This is actually a spelling error that's persisted over the years since the day's when spell checking was done by hand and not computer.  It should be Due Point, since this is a temperature at which the formation of storm clouds are due.  It should be noted that as the due point temperature increases, storms become more likely and the chance of increased severity is greater.  Since storm spotters aren't usually interested in formation of fog aside from that formed due to cooling of the air near the ground from large amounts of hail, any other use of this term is of no interest.  Constant attempts have been made over the years to determine the Tornado Due Point Temperature, but so far efforts have failed.

Differential heating - The inconsistent distribution of heat over an area such that sufficient heat to provide lift and to generate storms always occurs outside the area of storm spotting responsibility.  This is blatant discrimination by the sun and the atmosphere, all areas not covered by clouds should heat equally.  There ought to be a law on this!

Divergence - The rapid evacuation of a vicinity or vehicle following an serious occurance of either a rear frank downdraft or of the winds (second definition).  See Rear frank downdraft, Wind(s) (second definition).

Downburst - Occurs when a thunderstorm fails to maintain proper internal control.  This lack of control can result in very strong winds accompanied by precipitation coming down out of the storm and striking the ground at speeds high enough to cause considerable damage.  See Wind(s), first part of definition.

Flanking line- Either the line of cumulus clouds which stair-step into a supercell or the huge line of storm chasers and media vehicles which are found around the fringes of a major storm.

Fraidy hole -   [Slang] Term for a basement, cellar, or other supposedly protective location where people hide when the tornado shows up for a visit.  No part of a mobile home should be used as a fraidy hole, better to find some below-ground protected structure.  See Mobile Home.

Fried burrito - A small, inexpensive snack sold by most convenience stores on the South Plains and frequently eaten by storm spotters and chasers.  While quite tasty when hot, they can lead to intense stomach distress and other problems.  See winds, second part of the definition.

Glaciation - The changing of the storms appearance to a more fuzzy, wispy cloud, this suggests a weakening updraft and the storm usually in entering its elderly stage where it tends to lose its vitality, fails to keep up with things ( like mesocyclones, tornadoes etc.) and has much of its cloud top start to fall out as precipitation.

Gustnado - DisGUSTed that it's not a torNADO, a small-scale tornado wannabee, that is unable to associate with storm scale rotation, and is usually confined to the outflow region (i.e. the fringes ) of storm society.  They are capable of limited damage and usually disappear rather quickly.

Hail shaft - What the repair person, or occasionally your insurance agent will do to you when you've been caught in a large hail storm.

High risk -  Evaluation of the travel hazard level to local drivers, spotters, chasers, etc. who venture into an area designated by the Storm Prediction Center to have a 60 % or greater possibility of severe weather.  Due to the large amount of vehicles and people congregating at intersections, large parking lots and especially at free wireless internet access points, travel becomes highly difficult to impossible.  Fortunately, as the observed weather often falls below the implied risk level casualties are usually rather light.  Local merchants and restaurants don't seem to mind since the influx of visitors may improve business even if the locals are unable to get to stores or restaurants.  Some areas may resemble traffic at the only Wal Mart for 50 miles during the week before Christmas when the area is the only 60 % or better area in Tornado Alley.  Moderate risk areas and slight risk areas usually surround the high risk area.  See Moderate risk and Slight risk.

HP supercell - The most mysterious of the three storm upper-crust types.  These tend to hide their activities behind veils of precipitation.  They often appear heavily accessorized, with many bands about their storm towers.  Their tendency to shift the positioning of accessories and their mesocyclones show that they are trying to be trend-setters, but they don't seem to be able to dominate the social scene over the classic supercell or even the LP.  Due to their nature they try not to be seen too often with the other types especially the LP.  They also like to maintain their privacy, often keeping 'bears' hidden to prevent the nosy from spying out their secrets.  They tend to only appear at storm functions where very high levels of moisture are available, but often end up trashing the party due to their excessive precipitation.

Hybrid - A storm which hasn't decided which group it wishes to below to.  It tends to try different looks and different types of accessory clouds in an attempt to fit into the storm social scene.

Inflow - The movement of various weather observers into an area expecting severe weather.  When the movement tends to constrict into smaller areas it can lead to a convergence situation.

LP supercell - The lowest of the three levels of the storm society upper circle.  Despite a limited amount of the proper accessories it still expects the local atmosphere to revolve around it.  These are common on the high plains, where the lack of other socially dominant types usually makes it the most important thing around.  These will tend to be rather stingy with rainfall, but do tend to throw out large hail to show off their status.

Meso - Short for the computer's automated indication to the operator that 'I'm  a-showin' a MESs Of rotation in that storm.'  What do you expect from a computer system that was worked out in Oklahoma.  The spotter should note that this could indicate the formation of a mesocyclone (no known relation to the term above) and a tornado could develop and make a mess o' the spotter.  Frequent false indications may be the result of a sense of humor in the computer system and the radar.
 Note:  It's possible that the origin of mesocyclone may come from something similar, like 'the last time we saw these here rotation signs on th' radar we sure had us a mess o' cyclone.'  Okies, God help us.  At least it wasn't developed in Kansas or the computer would scream 'Auntie Em, Auntie Em, it's a twister, it's a twister!'  The term mesotwister was probably considered and rejected as soundin' a little stupid.

Microburst - A small intense downburst, possibly due to the storm's maintaining some but not complete control over its bodily functions.  May be either wet or dry, like with some people.

Mobile home -  While usually associated with manufactured housing or 'house trailers' this term when associated with tornadoes is expanded to include any home which may become 'mobile' when struck by a certain category of storm.  As tornado strength increases, the size and construction level of the structures which can become mobile also increase.  For example with an F-5 even
large, well built homes become 'mobile.'

Model -  An analytical method (sometimes a computer program) used to forecast (or modify) what weather will occur based on what a particular set of conditions will lead to when they reach the forecast area.  Different models may give a variety of results.  Forecasting seems to now be a case of selecting the model or models that fits the situation best.  See WAG, WT models.

Moderate risk - Evaluation of the travel hazard level to local drivers, spotters, chasers, etc. who venture into an area designated by the Storm Prediction Center to have a 40 % or greater possibility of severe weather.   Traffic conditions are usually better than with a high risk, but there will be areas of considerable convergence of weather observers of all types.  As the 40 % or greater chance seems to prove out more often than the severe possibilities with areas generating a high risk, it's just as well that traffic is lighter or the risk to drivers would have to be increased.  The 40 % area is also generally larger in areal coverage tending to lessen the traffic as well.  A slight risk area will usually surround the moderate risk territory.  See High risk and Slight risk.

Multicellular thunderstorm - A thunderstorm which has destroyed or severely damaged a minimum of two cellular telephone towers.

Rear frank downdraft - What frequently occurs following the consumption of convenience store hot dogs, fried burritos, or other fast food items whose age and condition are questionable.  As hot dogs were the first popular convenience store time the term has not been altered.  When the downdraft occurs it may lead to the rapid evacuation of the vicinity by all but the initiating person.  This has led to the removal of many passsengers while on storm watching sessions.  The term may actually have originated soon after the development of the single serving can of franks and beans.  See Winds, second definition.

Rope stage - Either a very weak tornado or one late in its lifecycle which is incapable of lifting anything secured to the ground.  In the cowboy days, rope was almost always used to secure belongings, hence the term.

Scud - In the early days of atmospheric science ( studying weather, etc.) in this country an inexperienced field researcher was watching a tornadic storm forming near a farm.  The farmer had come out to watch the storm and to try and move his cows to shelter.  The researcher, mesmerized by the sight of small pieces of cloud material being drawn toward then rapidly upward into what we know now as a wall cloud asked the farmer, 'that stuff sure is getting eat up quick, what do you call that'?  Mis-understanding the subject, the farmer believed he was talking about the cows nervously chewing away as usual.  ' 'sAt there's cud,' he replied, thinking the young man to be a complete fool.  'Scud, you say, well at least now I've got a name for it.'  After realizing his mistake, he never told anyone, consequently it's still called scud.

Shear - A term relating to types of damage left by high winds or a tornado.  For example, 'that light-pole was sheared clean off' etc.'  Directional shear is a variety of this, for example something could be sheared right off, or left sheared at the bottom.

Slight risk - Evaluation of the travel hazard level to local drivers, spotters, chasers, etc. who venture into an area designated by the Storm Prediction Center to have a 20 % or greater possibility of severe weather.   Traffic is usually somewhat heavier than normal but well below the limits requiring a  moderate risk.  The area is usually large enough to prevent problems other than at a few limited locales.  The worst cases only occur where there is a single, rather small area of 20 % or better possibility of severe weather and everyone crowds into that one area.  This may lead to the risk being upgraded to moderate.  See High risk and Moderate risk.  

Squall line -  Not a weather term, it's actually used to denote waiting lines with mothers holding one or more screaming babies.

Storm chasee - What any weather observer (spotter, chaser, etc.) can suddenly become after either failing to make a safe exit strategy or too slow a retreat  following a change of speed or direction of a severe storm.  Psychic storm observers claim to have heard the storm broadcasting "There they go!  Git 'em, get em!"  Observing multicell line storms, especially around bow echoes may lead to storm chasees without going through the storm spottee stage.  While dangerous, being a storm chasee can lead to very accurate position reports to the NWS as long as the chasee knows exactly where they are at the time.  The severe weather will be occuring at the same position!  See Storm spottee.

Storm chaser - People who have insufficient work to do during the severe weather season and who flood into "Tornado Alley" to try and see or photograph tornadoes.  While some actually provide useful research and interesting pictures which can benefit storm spotters, some are best used as bait.  If they were really interested in seeing twisters, they'd move to the South Plains and buy a house trailer.

Storm spottee - What any weather observer (spotter, chaser, etc.) can suddenly become after either a poor positioning choice or a sudden change in the speed or direction of motion in a dangerous storm.  A spottee must very quickly make decisions or risk becoming a storm chasee.  Certain observers in this situation who claim paranormal sensitivity have claimed that they clearly heard a psychic exclamation from the storm of "There's One!" usually just prior to the above mentioned sudden change.  See Storm chasee.

Storm spotter - Public service minded people who take time out of their lives to help the National Weather Service by serving as the NWS's eyes-in-the-field.  Spotters try and position themselves so that they may monitor severe storms and report conditions back to the NWS.  While probably less sensible than those who stay home and take cover, they are still not as crazy as the storm chaser who may have traveled half way around the world to try and see a F1 tornado destroy John Doe's trailer house.

Tail cloud - The cloud of dust and exhaust raised by the damage researchers, news media, and the storm junkies who follow along behind the path of a tornado, each for their own purposes.

Tornado - A violently rotating column of air, beneath a thunderstorm updraft in contact with the ground which acts like a spoiled uncontrollable brat.  It picks up everything it can, plays with it briefly, then discards it, usually broken, and seldom where it found it.  Depending on the parent cloud, this behavior could carry on for some time, or the ill-mannered child may be yanked back up into the parent cloud and forced to behave.  Inattentive storms may allow their 'children' loose over and over again, to wreak havoc on the poor earth.

Tornado bait - House trailer, mobile home, etc..  When found in clusters ( called trailer parks) they can be almost irresistible to tornadoes and strong thunderstorms.  Inexperienced or unlucky storm spotters and chasers as well as TV news crews may occasionally serve as bait as well.

TVS - (TeleVision Signature)  Acronyn for the Doppler radar's algorythm detecting rotation sufficient to attract either the TV Media storm followers or someone else with a video camera trying to get footage for the evening news shows or even a special live break-in during prime time.  TVS detections where no broadcast quality phenomena are occurring are likely caused by either the storm generating decoy rotation to hide actual events, ground level generated areas of rotation from observers and storm tourists etc. moving in opposite directions when no definite single best target exists, or when computer hackers employed by rival stations attempt to mislead other local stations to allow their employer to get an exclusive on an actual TVS.

TWISTER - A piece of movie fiction where tornadoes feature very strong low-level outflow, form upon demand, growl a lot, and show amazing selectivity toward objects they choose to lift.  Imagine, a storm that can pick up a semi and trailer full of gasoline, but that doesn't even budge a late model Dodge pick-up!

Twisted -  The viewers of Twister   who think that what they saw was the real thing.  Boy, are they in for a shock.

Vault - Final resting place of the remains (those that were found) of the unfortunate people who entered the wrong bear's cage.

WAG model - Wild A$$ Guess model, a forecasting tool used to determine what weather conditions will be for a given area at a specific time in the future.  This method is often used when computer models vary too much and the forecaster can't get a good handle on what to put out, hence the choice tends to be a WAG.

Wind(s) - If you're on the South Plains and aren't extremely familiar with this term, then you'd best leave or you're liable to get hurt.  The other somewhat archaic (i.e. 'old fashioned or out of use') definition refers to a personal intestinal condition which I'm too polite to discuss fully, but which most have experienced, too often second-hand.  See downburst, fried burrito, rear frank downdraft.

WT model - Wishful Thinking Model, a forecasting tool used to determine what weather conditions will be for a given area at a specific time in the future.  This method is often applied when a forecast zone either really needs something or conversely really doesn't need something.  The forecaster will often apply the WT results to the other models to come up with a favorable forecast.