Guides and Manuals

Here is a our database containing all our guides and manuals for our product and services

A

Absolute Humidity

Absolute humidity

Absolute humidity is the total amount of water vapor present in a given volume of air, expressed in grams per cubic meter.

Air Humidity

Air humidity

Air humidity refers to the amount of water vapor present in the atmosphere, influencing weather patterns and comfort levels.

Air Temperature

Air temperature

Air temperature is the measure of how hot or cold the air is at a specific location, typically recorded at 1.5 meters above ground level, and expressed in degrees Celsius or Fahrenheit.

Anemometer

An anemometer is a weather instrument used to measure wind speed, and in some cases, wind direction.

Artificial Intelligence

Artificial intelligence

Artificial intelligence is a branch of computer science focused on developing systems that replicate human cognitive functions—such as learning, problem-solving, and decision-making—by enabling machines to analyze data, recognize patterns, and make autonomous decisions, driving innovation across various industries.

Atmospheric Pressure

Atmospheric pressure

Atmospheric pressure is the force exerted by the weight of the air above any given point.

Atmospheric River

Atmospheric river

An atmospheric river is a long, narrow corridor of concentrated water vapor in the atmosphere that transports vast amounts of moisture from tropical regions toward higher latitudes, often resulting in heavy rain or snow when it reaches land.

B

Black Ice

Black ice

Black ice is a thin, nearly invisible layer of ice that forms on roads and other surfaces, often when moisture from light rain, drizzle, or melting snow freezes rapidly.

Bomb Cyclone

Bomb cyclone

A bomb cyclone is a mid-latitude storm that undergoes a rapid and explosive drop in atmospheric pressure, causing it to intensify dramatically.

Buildup Index

Buildup index

The buildup index is the total amount of fuel available for consumption in the duff and larger fuels. It represents the cumulative effect of drying on these heavier fuel layers.

C

Celsius

The Celsius scale is a temperature measurement system where the freezing point of water is defined as 0°C, while the boiling point is 100°C under standard atmospheric pressure.

Chernozem

Chernozem refers to soil with a deep brown or black color, typically due to a high organic matter content, such as decomposed plant and animal material.

Climate models

Climate models are complex mathematical representations of the Earth's climate system, used to understand past climate patterns and predict future changes.

Cloudburst

A cloudburst is a very intense and localized rainfall event, typically occurring over a short period.

Clouds

Clouds are visible collections of tiny liquid water droplets, ice crystals, or a mixture of both, suspended in the atmosphere when moist air cools and water vapor condenses onto microscopic particles.

Cold Drop

Cold drop

A cold drop, or DANA, is a slow-moving, high-altitude mass of cold air that causes severe weather, including torrential rain and flash floods, when it encounters warm, moist air near the surface.

Cold Front

Cold front

A cold front is an advancing mass of cold, dry air that pushes warmer, more humid air upward, often causing clouds, precipitation, and a drop in surface temperature.

Coriolis Effect

Coriolis effect

The Coriolis effect is the phenomenon where moving objects appear to curve due to Earth's rotation, with a rightward deflection in the Northern Hemisphere and a leftward deflection in the Southern Hemisphere.

Cyclone

A cyclone is a large-scale air mass that rotates around a central low-pressure area, typically bringing strong winds (119 km/h or more), heavy rainfall, and stormy weather conditions.

D

Dew point

The dew point is the temperature at which air, due to its humidity and temperature, becomes saturated and can no longer hold all its water vapor, resulting in condensation as dew, fog, or precipitation.

Downburst

A downburst is a powerful, localized column of rapidly descending air that spreads out horizontally upon hitting the ground, producing damaging straight-line winds.

Drizzle

Drizzle is a type of rain consisting of very small, scattered droplets with a diameter of less than 0.5 millimeters.

Drought

Drought is a prolonged period of below-average precipitation, leading to water shortages that impact ecosystems, agriculture, communities, and economies.

Drought Code

Drought code

The drought code is an index that represents the average moisture content of deep, compact, organic layers, and large logs. It indicates the long-term drying effects on heavier fuels.

Dry Bulb Temperature

Dry bulb temperature

The dry-bulb temperature is the air temperature measured by a standard thermometer, representing the ambient air temperature without considering the effect of moisture.

Duff Moisture Code

Duff moisture code

The duff moisture code is a rating that shows the moisture level of the middle layer of decomposing material on the forest floor, and how likely it is for fires to smolder and burn deeper into the ground.

Dunkelflaute

Dunkelflaute is a meteorological phenomenon characterized by prolonged periods of low wind and little to no sunlight, leading to a significant drop in wind and solar power generation.

E

El Nino

El Niño

El Niño is a climate pattern characterized by unusually warm ocean temperatures in the equatorial Pacific, impacting global weather patterns.

Evapotranspiration

Evapotranspiration is the combined process of water evaporation from soil and other surfaces and transpiration from plants, transferring moisture from the Earth's surface to the atmosphere.

Extratropical Cyclone

Extratropical cyclone

An extratropical cyclone is a large low-pressure weather system that forms outside of the tropics and is fueled by temperature contrasts between colliding air masses.

F

Fahrenheit

Fahrenheit (°F) is a temperature scale where water freezes at 32°F and boils at 212°F under standard atmospheric pressure, with the interval between these points divided into 180 equal degrees.

Ferrel Cells

Ferrel cells

Ferrel cells describe an atmospheric circulation pattern that occurs between approximately 30° and 60° latitude in both hemispheres and they play a crucial role in the transfer of energy between the tropics and the poles, influencing weather patterns and climates in the mid-latitudes.

Fine Fuel Moisture Code

Fine fuel moisture code

The fine fuel moisture code is a numerical rating that indicates the moisture content of small, dead fuels like leaves, twigs, and litter, and from there, the relative ease of ignition and flammability of those fuels.

Fire Weather Index

Fire weather index

The fire weather index is a numerical rating of fire intensity based on weather conditions such as temperature, humidity, wind speed, and precipitation, used to assess wildfire risk.

Flash Flood

Flash flood

A flash flood is a sudden, intense flooding event that typically occurs within six hours of heavy rainfall, often in low-lying or urban areas, and may also result from the failure of man-made structures.

Flood

A flood is an overflow of water, often caused by excessive rainfall, rapid snowmelt, storm surges, or the failure of dams, resulting in temporary or prolonged submersion of areas that are not typically underwater.

Fog

Fog is a dense collection of tiny water droplets or ice crystals suspended in the air near the ground, reducing visibility to less than 1,000 metres.

G

Global Atmospheric Circulation

Global atmospheric circulation

Global atmospheric circulation is the large-scale movement of air driven by the unequal heating of the Earth's surface due to its axial tilt, creating distinct pressure zones and wind patterns which distribute heat and moisture across the planet.

Global Forecast System

Global forecast system

The Global Forecast System (GFS) is a numerical weather prediction model that runs four times a day, and it processes data from satellites, weather stations, and other sources to generate weather forecasts.

Growing Degree Days

Growing degree days

Growing degree days is a measure of heat accumulation used to predict plant and insect development, calculated based on daily temperature thresholds.

H

Hadley Cells

Hadley cells

Hadley cells describe an atmospheric circulation of air near the equator where warm, humid air rises near the equator and moves toward the subtropics, where it descends as cooler, drier air where it starts moving back toward the equator.

Hail

Hail is solid precipitation that forms when supercooled water droplets freeze onto ice particles within strong thunderstorm updrafts, growing into chunks of ice that fall when they become too heavy to be lifted.

Heat Stress in Plants

Heat stress in plants

Heat stress in plants occurs when air temperatures exceed their optimal range, disrupting biological processes, reducing growth, and potentially causing damage or death.

Heat Wave

Heat wave

A heat wave is an extended period of abnormally high maximum air temperatures, lasting at least 2 to 5 days, often caused by a stationary high-pressure system.

High-Pressure Area

High-pressure area

A high-pressure area is an atmospheric zone where the weight and pressure of the air are greater than in surrounding areas, commonly resulting in sinking air, diverging winds, and typically associated with stable and fair weather conditions.

Hoar Frost

Hoar frost

Hoar frost is a type of ice that forms when water vapor in the air turns directly into ice—without becoming liquid—on a surface that is below 0 degrees Celsius, creating delicate, feathery ice crystals.

Hurricane

A hurricane is a rotating tropical cyclone with sustained winds of at least 74 mph (119 km/h), a well-defined eye, and the potential to cause severe damage through strong winds, heavy rain, storm surges, and flooding.

Hyperlocal Weather

Hyperlocal weather

Hyperlocal weather refers to weather data and forecasts that focus on a very small, precisely defined geographic area, often at the scale of a neighborhood, city block, or even a single street.

I

Inclement Weather

Inclement weather

Inclement weather refers to severe or unfavorable atmospheric conditions that significantly disrupt daily life, compromise safety–it includes weather events that are disruptive, dangerous, or damaging, often requiring adjustments in daily routines to mitigate their impact.

Initial Spread Index

Initial spread index

The Initial Spread Index is a rating that combines the effects of wind and fine fuel moisture on the expected rate of the initial spread of fire shortly after ignition.

Intertropical Convergence Zone

Intertropical convergence zone

The Intertropical Convergence Zone (ITCZ) is a low pressure band close to the equator where the trade winds from the Northern and Southern hemispheres converge, often resulting in heavy rainfall in the area.

J

Jet Stream

Jet stream

Jet streams are fast-moving bands of wind in the upper troposphere that flow from west to east, driven by the temperature difference between the equator and the poles, and they play a key role in shaping weather systems across the globe.

K

Kelvin

The Kelvin (K) scale is an absolute temperature scale that begins at absolute zero—the theoretical point where all molecular motion ceases.

L

La Nina

La Niña

La Niña is a climate pattern characterized by unusually cool ocean temperatures in the equatorial Pacific, impacting global weather patterns.

Lightning

Lightning is a sudden and powerful discharge of electricity that occurs during certain weather conditions, typically within or between cumulonimbus clouds and the ground.

Low-Pressure Area

Low-pressure area

A low-pressure area is an atmospheric zone where the weight and pressure of the air is less than in surrounding areas, commonly resulting in rising air, converging winds, and the development of clouds and precipitation.

M

Meridional Flow

Meridional flow

Meridional flow describes an atmospheric circulation pattern where winds, particularly the jet stream, move predominantly north-to-south and south-to-north.

Microclimate

A microclimate is a small, localized atmospheric zone with distinct weather conditions differing from the surrounding climates, created by variations in topography, vegetation, bodies of water, or human-made structures.

Monsoon

A monsoon is a seasonal shift in wind patterns that creates alternating wet and dry periods, forming a long-term weather cycle essential for water, agriculture, and daily life in many regions.

N

Numerical Weather Prediction

Numerical weather prediction

Numerical weather prediction is the process of using mathematical models of the atmosphere and oceans to predict the weather based on current weather conditions and physical laws governing atmospheric motion.

O

Occluded Front

Occluded front

An occluded front forms when a cold front overtakes a warm front, lifting the warm air aloft and producing a mix of warm and cold front characteristics, often with precipitation and changing weather.

Ozone Layer

Ozone layer

The ozone layer is a region of the stratosphere, 15 to 35 kilometers above Earth’s surface, where ozone (O₃) is concentrated and acts as a shield against harmful ultraviolet radiation.

P

Palmer Drought Severity Index

Palmer drought severity index

The Palmer drought severity index is a regional tool that estimates drought severity by modeling the balance between water supply and demand using precipitation and temperature data.

Permafrost

Permafrost is ground, regardless of type or whether it is located on land or under water, that remains at or below 0 degrees Celsius for at least two consecutive years.

Pesticide Drift

Pesticide drift

Pesticide drift refers to the unintended movement of agricultural chemicals, including pesticides, herbicides, fungicides, and insecticides, from their intended application site to surrounding areas due to environmental factors such as wind, evaporation, and improper spraying techniques.

Pluviometer

A pluviometer, also known as a rain gauge, is a weather instrument used to measure the amount of liquid precipitation that falls over a specific area during a defined period.

Polar Cells

Polar cells

Polar cells are atmospheric circulation patterns found near the poles, characterized by the movement of cold, dense air from the poles toward lower latitudes, influencing the frigid climates of these regions.

Polar Vortex

Polar vortex

A polar vortex is a large, low-pressure system of swirling, frigid air that forms in the stratosphere above Earth's poles, which is strongest in winter and directly influences the path of the polar jet stream and subsequent weather patterns.

Precipitation

Precipitation is any liquid or frozen water, such as rain, sleet, hail and snow, that forms in the atmosphere and falls back to the earth.

Q

R

Rain

Rain is a type of precipitation consisting of liquid water droplets that have condensed from atmospheric water vapor and fall to the Earth's surface due to gravity.

Relative Humidity

Relative humidity

Relative humidity is the ratio, expressed as a percentage, of the current amount of water vapor in the air to the maximum amount of water vapor the air can hold at that specific temperature and pressure.

Rime Ice

Rime ice

Rime ice forms when supercooled water droplets in fog or cloud freeze on contact with a surface that is below 0 degrees Celsius, creating either soft rime or hard rime depending on the temperature, wind, and moisture conditions.

Rossby Waves

Rossby waves

Rossby waves, also known as planetary waves, are large-scale undulations in Earth’s atmosphere and oceans that are driven by the variation of the Coriolis effect with latitude and play a crucial role in redistributing heat globally, shaping much of the variability in day-to-day weather.

S

Snow

Snow is a type of solid precipitation consisting of ice crystals that grow and aggregate into snowflakes as they fall from the atmosphere to the ground.

Solar Radiation

Solar radiation

Solar radiation is the electromagnetic energy emitted by the Sun, encompassing a wide range of wavelengths from invisible ultraviolet and infrared to visible light, which serves as the primary driving force for Earth's climate, ecosystems, and many human activities.

Squall

A squall is a sudden, powerful increase in wind speed that can be accompanied by intense rain, thunderstorms, or snow.

Stationary Front

Stationary front

A stationary front is a boundary between two air masses that meet but remain in place because neither is strong enough to displace the other, often leading to prolonged periods of cloudy, wet, or unsettled weather.

Stevenson Screen

Stevenson screen

A Stevenson screen is a standardized, ventilated shelter used to house meteorological instruments, protecting them from direct sunlight, precipitation, and other environmental influences while allowing for accurate atmospheric measurements.

Storm

A storm is a disturbance in the atmosphere, often characterized by strong winds, heavy rain, snow, hail, and thunder and lightning.

Storm Surge

Storm surge

Storm surges are an abnormal rise in sea level above the normal tide, caused mainly by strong winds and low atmospheric pressure from a storm pushing water toward the coast and flooding low-lying areas.

Sudden Stratospheric Warming

Sudden stratospheric warming

Sudden stratospheric warming (SSW) is a rapid rise of 30–50 °C in the polar stratosphere that disrupts the polar vortex, affects surface weather for weeks, and drives winter climate variability in mid-latitudes.

T

Temperature Inversion

Temperature inversion

A temperature inversion happens when cooler air is trapped beneath warmer air, preventing the normal circulation of air.

Thunderstorm

A thunderstorm is a weather event caused by rapidly rising warm, moist air that forms cumulonimbus clouds and produces lightning, thunder, heavy rain, and strong winds.

Trade Winds

Trade winds

Trade winds describe the winds that blow from east to west near the equator that form as warm air near the equator rises, and colder air moves in to replace it but is deflected by the Coriolis effect.

Tropical Cyclone

Tropical cyclone

A tropical cyclone is a rotating low-pressure storm system that forms over warm tropical ocean waters, characterized by a warm core, organized convection, strong winds, and heavy rainfall.

Troposphere

The troposphere is the lowest layer of Earth’s atmosphere, extending from the surface to an average height of about 12 kilometers, and is characterized by a steady decrease in temperature with altitude and the presence of virtually all of the planet’s weather.

U

Urban Heat Island

Urban heat island

The urban heat island effect describes higher near-surface air temperatures in urban areas compared to surrounding rural areas, primarily caused by reduced vegetation, usage of heat-absorbing materials, and man-caused heat.

V

W

Warm Front

Warm front

A warm front is an advancing mass of warm, humid air that slides up and over cooler air, often causing widespread clouds, precipitation, and a rise in surface temperature.

Water Vapor

Water vapor

Water vapor is the gaseous, invisible state of water in the atmosphere, where it plays a fundamental role in weather and climate.

Weather Station

Weather station

A weather station is a collection of instruments used to measure and record atmospheric conditions such as temperature, humidity, wind speed, wind direction, precipitation, and air pressure.

Wet Bulb Temperature

Wet bulb temperature

Wet bulb temperature is the lowest temperature air can reach by evaporating water, which cools the air until it is fully saturated with moisture.

Wind

Wind is the movement of air relative to the Earth’s surface, typically caused by differences in atmospheric pressure as a result of the sun’s uneven heating of the Earth.

Wind Gust

Wind gust

A wind gust is a brief, sudden increase in wind speed that lasts less than 20 seconds and is often followed by a lull in intensity.

Wind Shear

Wind shear

Wind shear is the change in wind speed and/or direction over a relatively short vertical or horizontal distance in the atmosphere.

X

Y

Z

Zonal Flow

Zonal flow

Zonal flow describes an atmospheric circulation pattern where winds, especially those in the upper atmosphere, move predominantly west to east along lines of latitude.