ATMO EXAM 3

Chapters 8 & 10

Air Masses and Fronts -
An air mass is a large body of air that has similar characteristics. such as temperature and humidity
They are associated with regions of calm winds and generally form flat/uniform topography
Where do they come from?
- P = polar
- T = topical
- A = artic
- m = maritime
- c = continental

ARCTIC IS COLDER THAN POLAR
You can mix and match source regions, land vs. water

cP: cold, dry, stable (this is what we normally have with cold front passage here in TX)
In an Extreme Case: cA: Cold air rushes down into U.S. from Canada: is an “artic high”
The Impacts include: Citrus crop damage in the southeast, and lake effects snows near Greater Lakes when cold air moves over the relatively warmer waters, leading to significant snowfall amounts.

mP: cool, moist, somewhat unstable
- Air from Pacific is lifted by mountains on west coast, producing rain and snow. Olympic mountains first, (weaker the more mountains it goes over). The orographic lift creates a rain shadow effect on the eastern side of the mountains, resulting in drier conditions in the interior regions of the state.

cT: hot, dry, stable aloft but unstable near the surface
Only really occurs in the U.S. in summer southwest
Few clouds and minimal precipitation
- Impacts: drought if a cT air mass remains in place for along time.

mT: warm, moist, and unstable
Flow northward from Gulf of Mexico provides fuel for thunderstorms in the eastern U.S.
Impacts: can lead to increased humidity and potential for heavy rainfall, particularly in the southeastern regions.
Usual air mass here in days prior to cold front
Entire summer here in TX
Also is the cause of flooding in California
Also severe weather in the central AND eastern U.S.
Also called the “Pineapple Express”

The boundary between air masses is called a : front

What causes air masses to move?
- high pressure systems, low pressure systems
More often than not it will be a result of the uneven heating of the Earth's surface, which leads to variations in temperature and pressure.
Usually low pressure systems (counterclockwise) are most common, causing air to rise, resulting in cloud formation and precipitation, while high pressure systems (clockwise) generally lead to clear skies and stable conditions.

A front: is the boundary between air masses normally refers to where this intersects the ground (in all cases except stationary fronts, symbols are placed pointing the direction of movement of the front.)
Warm Front - red circles
Cold Front - blue triangles
Stationary Front - blue triangles AND red circles
Occluded Front - purple triangles AND circles

How to find a front - sharp change in dew point, shift in wind direction
- wind often coming from the air mass source region
“kink” in isobars (or a trough of low pressure)
- temperature discontinuity, with a noticeable difference in temperatures on either side of the front.

Cold fronts - “dome” of dense cold air is replacing warm air
Cold air rises, warm air sinks
Leading edge of the cold front is steep- often leads to strong upwards motion
Associated weather patterns typically include thunderstorms and heavy precipitation, as the warm air is forced to rise rapidly, cooling and condensing to form clouds.

Polar vs. Arctic front
- Polar: cold, dense air with a frontal zone that can extend over long distances, creating a stark temperature gradient and often leading to varying weather patterns.
Actic: very cold, denser air but shallower frontal zone that may only extend up to 1 to 2km , leading to relatively stable conditions, although it can also result in localized heavy snow and flurries due to the vertical lifting of the air.

What happens when a cold front passes -
- A cold front typically displaces warm air, leading to a drop in temperature, a shift in wind direction, and often an increase in precipitation, which can manifest as intense showers or thunderstorms.
Wind during a cold air pass - typically shifts from a southerly or southwesterly direction to a more northwesterly or northerly flow, resulting in cooler and drier air following the front.
Temperature during a cold front pass - As the cold front moves in, temperatures tend to drop significantly, often resulting in cooler conditions that follow the front.
Clouds during a cold front pass - are typically characterized by rapid development, leading to the formation of cumulonimbus clouds, which are associated with severe weather conditions such as heavy rain, lightning, and strong winds.
Precipitation during a cold front pass - is typically characterized by short, intense showers, often leading to rapid changes in weather conditions as the front moves through.
Dew Point during a cold front pass - The dew point typically decreases as the colder, drier air replaces the warmer, moisture-laden air ahead of the front, leading to clearer skies and reduced humidity.

Warm fronts -
- Warm air replacing cool air
Relatively gentle slope - leads to broad area of upward motion
Warm fronts usually move slower than cold fronts
Often associated with cloud formation and precipitation, which can lead to extended periods of light rain as the warm air rises and cools.
Gets pushed up and over the cooler air receding, resulting in a gradual and steady transition in weather conditions.
Wind during a warm air pass - typically shifts to a southerly or southwesterly direction, bringing with it warmer temperatures and an increase in humidity.
Temperature during a warm air pass - tends to rise significantly, as the warmer air mass replaces the cooler air, contributing to a more unstable atmosphere that can spark additional weather events.
Clouds during a warm air pass - often develop into stratiform layers, leading to extended periods of overcast skies and potentially producing light precipitation as the warm air forces moisture-laden air higher into the atmosphere.
Precipitation during a warm air pass - can vary from light drizzle to moderate rainfall, depending on the moisture content of the air mass and the strength of the warm front.
Dew Point during a warm air pass - typically increases as warmer air holds more moisture, which can enhance humidity levels and contribute to the development of fog or low clouds if conditions are right.

Stationary Fronts -
It does not move much
In some cases where air is moist on both sides, stationary fronts can lead to flooding, rain forms along the front and can persist for many days
Characteristics: Stationary fronts can create prolonged periods of precipitation, and the impact on local weather can be significant due to the persistent nature of the front.

Extreme Weather -
Both stationary and warm fronts can be related to ice storms and bands of precipitation types
Impact on Ice Storms: Ice storms frequently occur in regions impacted by these fronts, especially when warmer air overrides a cold air mass, resulting in freezing rain.
- Types of Precipitation: The persistent nature of stationary and warm fronts can also produce mixed precipitation, including sleet and snow, depending on the temperature profile.
In winter it can bring all 4 types
A warm front is where warm air is replacing cold air, like a cold front in reverse

Occluded Front -
Cold front catches up to and overtakes a warm front
purple line with triangles and semi-circles
Two types - cold occlusion and warm occlusion
warm type is the most common, where the cold air remains at the surface and the warm air is lifted, resulting in cloud formation and precipitation.

Warm front is: three different air masses stacked ontop of one another

Warm occlusion - occurs when a cold front catches up to a warm front, leading to the lifting of warm air over both cold air masses, typically resulting in complex weather patterns including widespread clouds and precipitation.

Cold occlusion - occurs when a cold front overtakes a warm front, causing the cooler air to lift the warm air off the ground, which can also lead to cloud formation and precipitation, though often with less stability compared to warm occlusions.

Other boundaries-

Drylines - Drylines are boundaries that separate moist air from drier air, often associated with severe thunderstorms in the central United States, as they create an ideal environment for convection.
Sets up in southern Plains very regularly
Severe storms often form on dryline
Important to know for being in TX, such as in west TX (maritime tropical air vs. continental tropical and will see vegetative differences.)
Separates mT and cT

Mid - latitude cyclones -

Sometimes fronts exist on their own, but often they are apart of a bigger weather system: extratropical (or midlatitude) cyclone
Cyclones (“lows”) are important part of midlatitude weather
- Bring much of the precipitation in the cool season, but also hazardous weather (winds, snow, etc.)
First ideas were developed by Norway in the 1920’s - “polar front theory”
Bergen School included many of the founders of the field of meteorology
Before this time, people knew that rain and snow usually came with low pressure, but not much more - the Bergen school detailed observations to develop the theories of how the atmosphere works

Polar Front theory - a fundamental concept in meteorology describing the boundary between cold air masses from the poles and warm air masses from the tropics, which leads to significant weather phenomena such as cyclones and frontal systems.
Under the right conditions, a wavelike- kink forms on the front, a frontal wave.

Wave-like cyclones develop and move along polar fronts.

Polar front theory for extratropical cyclones -
- Start with a stationary front ( the boundary line between air masses like the polar front) and a wave can develop “incipient cyclone” as fronts lie in troughs
- region of air ahead of cold fronts and behind warm front is called a warm sector

The cold front advances, wave continues to grow to the mature stage
Fast-moving cold front starts to overtake warm front: occlusion
The development and stretching of a cyclone is called: cyclogenesis
Eventually, cyclone occludes completely and begins to weaken
During occlusion, warm sector is lifted off the surface
Low completely surrounded by cold air, which cuts off energy of rising warm air
Triple Point - This is the point where the cold front, warm front, and occluded front all meet, creating a unique weather phenomenon characterized by varying air masses and potential for severe weather.

Midlatitude cyclones -

These storms get their energy from many sources
- The temperature contrasts between the polar air masses and the warmer, moist air from the tropics, which leads to significant changes in pressure and wind patterns.
Latent heat from condensation in rising air
Warm air rises and cold air sinks - turns potential energy into kinetic energy
This is just the surface evolution
Low “fills” - increasing pressure/increasing mass in column = low weakening
Low “deepens” - decreasing pressure/decreasing mass in column = low strengthening

Polar front is a belt of thermal contrast
Cyclone “families” are quite frequently found along polar fronts, in various stages of development.

Source Regions -
- regions with propensity for cyclogenesis
- Gulf of Mexico, Atlantic ocean east of the carolinas
- Eastern slopes of the rocky and Sierra Nevada mountains
- “All lows go to Chicago”

Cape Hatteras. NC- storms are called northeasters (nor’easters)
It os called this because - of the region's unique geography and the prevailing winds that often bring moisture from the Atlantic, creating intense winter storms.
“Bomb” is an explosive cyclogenesis
- Low deepens 24mb in 24hrs

Extratropical cyclones typically have a COMMA shape when viewed from infrared satellite imagery

Upper air review -
- cold air aloft means low pressure (heights)
Warm air aloft means high pressure (heights)

Vertical Structure -
- Thermal lows are shallow, oftenn temperature induced, low pressures
Mi-latitude cyclones are dynamic lows that are usually stronger with height
What happens at the surface is in response to things happening aloft
Remember: surface pressure is related to the amount of mass above you at the surface
Convergence - occurs when winds from different directions come together, leading to an increase in air pressure at the surface as air is forced to rise. (the addition of mass.)
Divergence - occurs when winds are moving away from each other, resulting in a decrease in air pressure at the surface as air is drawn away and replaced by rising air from lower levels. (The removal of mass.)
Do surface highs and lows form directly below upper level highs and lows? No, because air is only flowing in or out at the surface. Lows and highs would quickly dissipate. Air is pulling up at the surface low center, which is the opposite of a “low” pressure.
The piling up of air is called - convergence
Convergence - occurs when winds are moving towards each other, resulting in an increase in air pressure at the surface as air is pushed down, leading to the formation of surface lows. This influx of air causes rising motion and is typically associated with cloud development and precipitation.
High is the opposite with spreading out of air called divergence.
Divergence - occurs when winds are moving away from each other, leading to a decrease in air pressure at the surface as air is drawn upwards, which can result in clear skies and limited cloud formation.
You WANT divergence aloft to be greater than the surface convergence. You want more air to be removed from the column aloft than brought into the column at the surface.
We want circulation to set up like in our earlier pink and blue column examples
Aloft, convergence occurs upstream of a trough, and divergence occurs downstream
The surface lows and highs form under these areas
A cyclone will tilt WESTWARD with height

Longwave - Large-scale waves that influence weather patterns and can lead to prolonged periods of certain weather conditions, often lasting several days to weeks.
Shortwaves - Smaller-scale disturbances that move through the flow, affecting local weather conditions over shorter time frames, typically lasting only hours to a few days.

Jet streak- A narrow band of strong winds within the jet stream that can enhance lift and lead to the development of storms or disturbances in the atmosphere.
Usually look at the 200-300mb level
Often embedded within the trough ridge pattern
Divergence pattern in jet streaks - this refers to the area where the air is spreading apart, which typically occurs downstream of the jet streak, leading to rising motion that can enhance cloud formation and precipitation.
Convergence pattern in jet streaks - this describes the region where air is coming together, usually found upstream of the jet streak, which creates sinking motion and can inhibit cloud development and precipitation.
In curved flow, (cyclonic/counterclockwise), the left side pattern is dominant
Upper level convergence with surface pressure falls - left side
Upper level Divergence with surface pressure rises - right side

The most disruptive storm of the century - The March storm of 1993
Was a frontal wave on the 12th off the coast of Texas
In the air a shortwave, moving rapidly around a longwave
On the 13th it intensified into a deep open wave cyclone centered over Florida
(Had the classic comma shape)
Counterclockwise spin

What is the coldest air mass type we can experience in TX? - Continental Arctic
A front is a boundary between air masses
A front is always accompanied by a sharp change in temperature - False
What type of front would be associated with the most drastic, at times rapid, change in precipitation type? - A warm front

The three ingredients for thunderstorms are: moisture, instability, and lift
NWS definition of a severe thunderstorm -
Hail over 1” in diameter
Surface wind gust of 50km (58mph) or greater
Tornadoes
Other important hazards not considered in the defintion (but still important) -
Lightning
Flash flooding

Moist Parcels -

We assume that air parcels can heat and cool, but that they don’t mix in air from the outside The pressure of a parcel is assumed to adjust instantaneously to its environment
When condensation occurs (at the LCL), latent heat is released inside the parcel
So, instead of cooling at 9.8C per km it cools slower - usually around 6C per km- this is the moist-adiabatic lapse rate

Environmental lapse rate -
Parcels (individual bubbles of air) always rise and sink at either the dry or moist adiabatic rate
The environment (the air surrounding the parcel) can have a variety of temperature profiles
This environmental rate is measured with radiosondes, (on weather balloons)
Since the adiabatic lapse rate is known, we can compare them to the environmental lapse rate to determine whether the parcel will be stable, or unstable
- If a parcel is forced to rise (lift) and it’s warmer than its environment, it will continue to be unstable
- If it is forced to rise and is cooler than its environment, it will sink back down to the original position to be stable

Deep convection -
Updrafts and rising, moist air is what leads to deep convection
Once we create precipitation, we often have to care about how that air is falling as well
As precipitation falls it often evaporates (latent cooling) which changes temperature
The falling air is called a: downdraft
The downdraft is important because it can organize the storm, kill the storm, or yield severe hazards

Thunderstorm - traits-
deep convective storms containing lightening and thunder
Convective storms that form with rising air
Several triggers (turbulent eddies, unequal surface heating, terrain, coundaries)
Severe thunderstorms
Large hail, wind gusts greater than or equal to 50 knots, or a tornado

Classifications of convective cells -
Ordinary cells - one updraft, one downdraft
Environments have little wind shear, (changing of wind in height), (uniform wind speed and direction with height)
Last 15-30 minutes or an hour at most
examples: small summer thunderstorms in the afternoon

Ordinary thunderstorms -
Three stages of an ordinary (air mass, pulse, “popcorn”) thunderstorm:
- Cumulus stage: moist air rises and condenses
Mature Stage: Dry air is “entrained” and leads to downdraft and gust front - heavy precipitation
Dissipating stage: Downdraft cuts off moist updraft, clouds and raindrops evaporate

Classifications of convective cells-
Multicell - a complex of multiple convective cells that are often organized into clusters, where both updrafts and downdrafts interact, leading to varying intensity and longevity of precipitation.
Group of ordinary cells at different stages in their life cycles
What is the environment difference between the ordinary and the multi-cell? The ordinary cells typically thrive in an environment characterized by weak vertical wind shear and lower instability, whereas multicell convective systems benefit from moderate to strong vertical wind shear, allowing for more organized storm structure and enhanced precipitation. In contrast, the multicell systems can create multicellular storms that can persist longer due to the interaction between updrafts and downdrafts, leading to localized severe weather events, such as hail and flash flooding.

The role of tilt and shear -
- If there is vertical wind shear, the updraft may be tilted and the inflow may not be cutoff
- This is the key to all non-ordinary thunderstorms
Wind shear allows a storm to tilt in such a way that the updraft rides up and over the downdraft

Multi-cell thunderstorms - The gust from one cell will provide the lifting for a new one to form
- Each cell lasts 15-30 min, but the whole system can last for many hours

Mesoscale convective systems -
- When multicell storms grow into even larger groups, they are called mesoscale convective systems (MCS), which can produce severe weather over extensive areas, including heavy rainfall, strong winds, and even tornadoes.
MSCs provide about half of the summer rainfall in the plains and midwest and nearly 60% of the rainfall tropics!
Within this group there are several types:
- squall lines: long line of convection
- bow echoes - curbed line of convection “bows” out
Mesoscale convective complexes (MCCs) - large circular cluster of storms

MCS motion -
Repeatedly going over the same area (sometimes)
Individual cells are carried by the winds aloft
As new cells form and old ones dissipate systems as a whole ends up moving to the right of the wind
Generally, if the relative humidity in the storm environment is fairly low, strong downdrafts will form and the system will move quickly - strong downdrafts will form and the system will move quickly - strong winds
If the RH is high, the downdrafts will be weaker, leading to slower movement of the system and allowing for greater moisture retention, which can enhance storm development.

Classifications of convective cells -

Supercell - a highly organized thunderstorm characterized by a rotating updraft (mesocyclone) that can produce severe weather phenomena, such as large hail, damaging winds, and tornadoes.
Nearly steady, rotating updraft
- A single supercell can last for many hours
In strong wind shear (speed and/or direction are changing with height) thunderstorm updrafts can rotate - necessary for a supercell
Wind shear creates horizontal rotation - this is tilted into the vertical and stretched by the updraft to make a rotating storm
Rotation keeps the precipitation and the cold downdrafts away from the updraft, so the storm can last for hours
Main features of a supercell include:
A strong rotating updraft (mesocyclone): This is the primary characteristic that distinguishes supercells from other thunderstorm types.
Anvil-shaped top: The cloud top spreads out in an anvil formation at high altitudes due to the strong updraft.
Heavy precipitation and hail: Supercells often produce intense rainfall and large hailstones, which can cause significant damage.
Severe weather potential: They are capable of generating tornadoes, strong winds, and flash flooding.
Gust front: When a thunderstorm downdraft hits the ground, it creates a gust front, which can lead to the development of new cells or enhance existing ones.
Verga: A meteorological phenomenon where water droplets are suspended in the air but do not reach the ground, often seen in association with thunderstorms.

Supercell Flavors -
Classic - heavy rain, strong winds, hail, and frequent tornadoes are characteristic of this type, making it one of the most severe storm systems.
LP (Low precipitation) - a variant that typically produces less rain compared to classic supercells, often leading to weakened updrafts but can still generate severe wind gusts and isolated tornadoes.
HP (high precipitation) - characterized by very heavy rainfall, often leading to flash flooding, while the strong updrafts can also produce large hail and an enhanced risk for tornadoes. (and hidden tornadoes)
Supercells ALWAYS rotate
Often Split and can split into multiple ones
Because of rotation, usually move in a different direction than regular thunderstorms, and this leads to unique storm paths and behaviors that can be difficult to predict.

Lightning and Thunder -
- Lightning - a discharge of electricity in a cloud
- can heat the air to 30,000C
causes the air to expand explosively and creates thunder
Light travels much faster than sound
Thunder travels about 1 mile in five seconds
Types of lightning -
Cloud-to-ground: This is the most common type of lightning, occurring when a discharge occurs between a cloud and the ground.
Intra-cloud: Here, lightning occurs within a single cloud, often creating a branching pattern.
Cloud-to-air: This type involves discharges between clouds and the surrounding air, which can create bright flashes that illuminate the sky.
Ground-to-cloud: This rare type of lightning travels upward from the ground to a cloud, typically occurring during strong thunderstorms.
Ball lightning: A phenomenon characterized by glowing, spherical shapes that appear during thunderstorms, often lingering for several seconds before disappearing.
Cloud-to-cloud: This type of lightning occurs between two or more clouds and is often responsible for the extensive lightning displays seen during major storm events, creating a spectacular visual effect in the sky.
There is always thunder when it is raining - you just may not be close enough to hear it

Cloud electrification -
- Accretion occurs on hail/graupel latent heat release keeps the hailstone warmer than the surrounding drops and ice crystals
The warmer the hail/graupel transfers positive ions to the colder ice crystals (at contact)
when super-cooled liquid droplets freeze on hail/graupel and charged ice splinters off
TYPICAL charge distribution -
Positive charge accumulates near the top of the storm cloud, while negative charge is more concentrated at the base.
This distribution leads to the development of strong electric fields that can result in lightning discharges.
Positive charge at the surface
If charge becomes sufficiently large, lightning occurs
How does lightnening charge occur - this process begins with the separation of positive and negative charges within a storm cloud, facilitated by updrafts and turbulence that distribute water droplets and ice particles. As these particles collide and interact, electrons are transferred between them, leading to an accumulation of negative charge in the lower regions of the cloud and a corresponding positive charge in the upper regions. This separation creates a significant potential difference, which, when overcome, enables the discharge of energy in the form of lightning.

Severe winds -

Along the gust front of a squall line, winds can be very strong, especially in the “bow”
A strong, localized downdraft can occur, creating sudden bursts of wind that propel debris and can lead to damage on the ground.

Thunderstorms and flooding -
- Flash floods rise rapidly with little or no advance warning, and can occur in various terrains, making them particularly dangerous for those caught in low-lying areas.

The land warms up faster than surrounding bodies of water, creating localized areas of low pressure that can enhance upward convection and lead to the development of thunderstorms.

Tornadoes -
Defined as a violently rotating column of air, in contact with the ground, and below a cumuliform cloud.
Basic requirements are the usual for a thunderstorm (moisture, instability, lift), and strong vertical wind shear
Not all super cells produce tornadoes
Wind shear along the rear flank downdraft causes spinning vortex tube that is pulled into thunderstorm by the updraft
Spinning vortex tube “stretched” by the mesocyclone into the vertical
Before a tornado forms, a low cloud called a “wall cloud” will begin to develop beneath the mesocyclone, indicating strong upward motion and the potential for tornado formation.
Favorable conditions:
Atmospheric instability: Warm, moist air at the surface coupled with cooler, drier air aloft to promote convection.
Wind shear: A significant change in wind speed and direction with height, aiding in the organization and rotation of thunderstorms.
Moisture availability: Adequate humidity to support thunderstorm development and strengthening.
(basically the same as supercell)
Tornado Characteristics:
Funnel cloud until circulation reaches ground
Mostly < 135 mph, but can exceed 250 mph
Diameters: most are 300 to 2000ft and are as small as 20ft and as big as 1 mile long!
Most have a counterclockwise motion
Mostly move SW to NE, 25 to 50mph
Cyclostrophic balance: PGF and Centrifugal
Winds are asymmetric
If you are facing a tornado, the strongest winds will be on the left side
Can have multiple vortexes or internal suction vortices

Enhanced Fujita scale for tornado intensity -

Damage is assessed after the tornado
Originally developed by Dr. Ted Fujita of the University of Chicago in the 1970’s
Updated in 2007 to the “Enhanced Fujita” scale
EF4 and EF% tornadoes are very rare, but most deaths are caused by them, we need to see extensive damage to determine what we rate the tornado
First EF5 (new scale) was in Greensburg KS, May 4, 2007
Almost 2 miles wide 205 mph

Tornado Outbreaks -
- Typically, conditions will be favorable over a large area for supercells, and we have many tornadoes for a synoptic event.
Tornado families - single supercell, multiple tornado “drops”

Tornadic winds & Doppler radar -

Doppler radar measures the speed of precipitation toward and away from radar
Forecasters look for a velocity couplet and TVS (Tornado Vortex Signature)
NEWRAD is the national Doppler system
- Major recent upgrade to dual polarization (dual-pol) adds significant severe weather upgrades
Doppler Radar - A shift in frequency allows radar to see motion towards or away from the radar, only

Non-supercell tornadoes -

Boundaries give rise to low-level rotation
Convection stretches rotation
Bookends and bow echoes
Mainly in Colorado and can also happen in Florida due to sea breezes and varying terrain, which create favorable conditions for these phenomena to develop. Additionally, the presence of moisture and instability in the atmosphere often enhances storm intensity, leading to severe weather events.

Waterspouts -

A rotating column of air that is connected to a cumuliform cloud over a large body of water
Tornadic waterspout vs. fair weather
Dust Devils are cousins, same balance
- Cyclostrophic - a balance between the Coriolis force and the pressure gradient force is essential for the development and maintenance of these phenomena.

When a parcel is not saturated and rising, it will cool at what lapse rate - the dry adiabatic lapse rate, which is approximately $10 \, ext{°C/km}$ .

When a parcel is saturated and rising, it will cool at what lapse rate - the moist adiabatic lapse rate, which is approximately $6 \, \text{°C/km}$ .

The level at which a parcel becomes less dense than the surrounding environment is known as what abbreviation - the Level of Free Convection (LFC), which is important for understanding cloud formation and thunderstorm dynamics.

True or False a downdraft is associated with sinking air - True. A downdraft occurs when cooler, denser air sinks rapidly, often resulting in precipitation and instability in storm systems.

The primary factor that distinguishes a supercell thunderstorm from an ordinary thunderstorm is - the presence of a rotating updraft, known as a mesocyclone, which allows it to maintain its structure and intensity for longer periods and under more severe conditions.

True or False the key ingredient that is needed for a thunderstorm to be more than ordinary is vertical shear - True. Vertical shear refers to the change in wind speed and direction with height, which helps organize and sustain storm structures by allowing rotating updrafts to develop and preventing the downdraft from interfering with the updraft.

Which three would be considered an example of vertical wind shear? wind speed and direction not changing with height, wind speed and direction changing with height, wind direction changing with height, wind speed changing with height - The following three would be considered an example of vertical wind shear:

wind speed and direction changing with height,
wind direction changing with height,
wind speed changing with height.

Which of the following are favorable conditions for tornadic supercell thunderstorms? Select all that apply: high atmospheric instability, strong thunderstorm updraft, strong upper-level convergence along the jet stream, moisture through the atmosphere, winds increasing with height - all are necessary components that contribute to the formation and intensification of these severe storms.