Weather — page 18 of 38

Weather terms

1701. Infiltration Rate The rate of water entry into the soil expressed as a depth of water per unit of time in inches per hour or feet per day.
1702. Inflow Bands Bands of low clouds, arranged parallel to the low-level winds and moving into or toward a thunderstorm.
1703. Inflow Jets Local jets of air near the ground flowing inward toward the base of a tornado.
1704. Inflow Notch A radar signature characterized by an indentation in the reflectivity pattern on the inflow side of the storm.
1705. Inflow Stinger A beaver tail cloud with a stinger-like shape.
1706. Influent Seepage Movement of gravity water in the zone of aeration from the ground surface toward the water table.
1707. Influent Stream Any watercourse in which all, or a portion of the surface water flows back into the ground namely the, vadose zone, or zone of aeration.
1708. infrared brightness temperature (°C) (°C) The downwelling atmospheric emission in the 9.9 to 11.4 micrometers band; in general, relatively warmer temperatures imply "thicker" clouds.
1709. Infrared Radiation Electromagnetic radiation whose wavelengths lie in the range from 0.75 micrometer to 1000 micrometers; invisible long wavelength radiation (heat) capable…
1710. Infrared Satellite Imagery This satellite imagery senses surface and cloud top temperatures by measuring the wavelength of electromagnetic radiation emitted from these objects.
1711. Infrastructure Management Board (IMB) (IMB) ACRF management team that manages the overall budget, planning, user request screening, activity implementation, and impact assessments for the ARM…
1712. Initial Detention The volume of water on the ground, either in depressions or in transit, at the time active runoff begins.
1713. Inland freshwater wetlands Swamps, marshes, and bogs found inland beyond the coastal saltwater wetlands.
1714. Inland Hurricane Warning Issued for interior counties that sustained winds of 74 mph or greater associated with a hurricane are expected within 24 hours.
1715. Inland Hurricane Watch Issued for interior counties when sustained winds of 74 mph or greater associated with a hurricane are possible within 36 hours.
1716. Inland Tropical Storm Warning Issued for interior counties when sustained winds of 39 to 73 mph associated with a tropical storm are expected within 24 hours.
1717. Inland Tropical Storm Watch Issued for interior counties when sustained winds of 39 to 73 mph associated with a tropical storm are possible within 36 hours.
1718. INLD Inland
1719. inorganic chemical composition The chemical composition of an aerosol, with the exception of those with hydrocarbons, and usually including carbides, oxides of carbon, metallic…
1720. Inorganic compound Historically, chemicals that could not be derived from living processes. In modern usage, chemicals that do not contain carbon, although carbonates and a…
1721. Inorganic fertilizer See synthetic fertilizer.
1722. Insolation The solar power density incident on a surface of stated area and orientation, usually expressed as Watts per square meter or Btu per square foot per hour.
1723. Instability A lack of consistent phenotype, usually as a result of uncontrolled genetic changes.
1724. instantaneous radiative flux (IRF) (IRF) An approach that involves collecting data on the distribution of radiation and the radiatively active constituents of the atmosphere and radiative…
1725. INSTBY Instability- The tendency for air parcels to accelerate when they are displaced from their original position; especially, the tendency to accelerate…
1726. instrument data processing circuit Data processing module that transforms data from the instrument output format into a designed data structure in netCDF format.
1727. Instrument Flight Rules Refers to the general weather conditions pilots can expect at the surface and applies to the weather situations at an airport during which a pilot must…
1728. instrument mentor The technical point of contact for ACRF instrument systems. Mentors are the presumed experts on the instrument and the data it provides.
1729. Instrument Shelter A boxlike structure designed to protect temperature measuring instruments from exposure to direct sunshine, precipitation, and condensation, while at the…
1730. instrumental record data measured using instruments, such as thermometers and rain gauges.
1731. Intangible Flood Damage Estimates of the damage done by disruption of business, danger to health, shock, and loss of life and in general all costs not directly measurable which…
1732. Interbasin Transfer The physical transfer of water from one watershed to another.
1733. Interception The process by which precipitation is caught and held by foliage, twigs, and branches of trees, shrubs, and other vegetation, and lost by evaporation…
1734. Interception Storage Requirements Water caught by plants at the onset of a rainstorm. This must be met before rainfall reaches the ground.
1735. Interflow Lateral movement of water in the upper layer of soil.
1736. interglacial a time interval characterized by lack of glacial ice in mid-latitudes, such as modern Holocene climate.
1737. Intergovernmental Panel on Climate Change (IPCC) The IPCC was established jointly by the United Nations Environment Programme and the World Meteorological Organization in 1988.
1738. Intermediate Synoptic Times The times of 0300, 0900, 1500, and 2100 UTC.
1739. Intermittent Stream A stream that flows for a portion of the year but occasionally is dry or reduced to a pool stage when losses from evaporation or seepage exceed the…
1740. International Date Line The line of longitude located at 180 degrees East or West (with a few local deviations) where the date changes by a day.
1741. Interplanetary Magnetic Field (abbrev. IMF) In solar-terrestrial terms, the magnetic field carried with the solar wind.
1742. Interpolate To estimate a value within an interval between two known values. This technique is sometimes used with computer models for locations in between the…
1743. Intertropical Convergence Zone (ITCZ) The region where the northeasterly and southeasterly trade winds converge, forming an often continuous band of clouds or thunderstorms near the…
1744. Intraseasonal Oscillation Oscillation with variability on a timescale less than a season. One example is the Madden-Julian Oscillation.
1745. INTS Intense
1746. INTSFY Intensify
1747. INTST Intensity
1748. Inundation The flooding of normally dry land, primarily caused by severe weather events along the coasts, estuaries, and adjoining rivers.
1749. Inversion A chromosome re-arrangement, which involves the re-orientation of a segment so that the order of a linear array of genes within it is reversed.
1750. Invest A weather system for which a tropical cyclone forecast center (NHC, CPHC, or JTWC) is interested in collecting specialized data sets (e.g.
1751. INVOF In the vicinity of
1752. INVRN Inversion- Generally, a departure from the usual increase or decrease in an atmospheric property with altitude.
1753. Ion An atom or molecule that has lost or gained one or more electrons and has become electrically charged as a result.
1754. Ionosphere The region of Earth's atmosphere that extends from about 50 to 300 miles above the surface of the planet and is made up of multiple layers dominated by…
1755. Ionospheric Storm A disturbance in the F region of the ionosphere, which occurs in connection with geomagnetic activity
1756. IPV Improve
1757. IR Infrared Satellite Imagery
1758. Iridescence Brilliant spots or borders of colors in clouds, usually red and green, caused by diffraction of light by small cloud particles.
1759. Iridescent Clouds Clouds that exhibit brilliant bright spots, bands, or borders of colors, usually red and green, observed up to about 30 degrees from the sun.
1760. Irradiance The direct, diffuse, and reflected solar radiation that strikes a surface.
1761. Irreversibilities Changes that, once set in motion, cannot be reversed, at least on human time scales.
1762. Irrigation The controlled application of water for agricultural purposes through manmade systems to supply water requirements that are not satisfied by rainfall.
1763. Irrigation Requirement Quantity of water, exclusive of effective precipitation, that is required for crop production. See crop irrigation requirement.
1764. Isallobar A line of equal change in atmospheric pressure during a specified time period.
1765. Isentropic Analysis A way in the forecaster can look at the atmosphere in 3-dimensions instead of looking at constant pressure surfaces (such as the 850 mb, 700 mb, 500 mb…
1766. Isentropic Lift Lifting of air that is traveling along an upward-sloping isentropic surface. Isentropic lift often is referred to erroneously as overrunning, but more…
1767. Isentropic Surface A two-dimensional surface containing points of equal potential temperature.
1768. Isobar A line connecting points of equal pressure.
1769. Isobaric Chart A weather map representing conditions on a surface of equal atmospheric pressure.
1770. Isobaric Process Any thermodynamic change of state of a system that takes a place at constant pressure.
1771. Isobath An imaginary line on the earth's surface or a line on a map connecting all points which are the same vertical distance above the upper or lower surface of…
1772. Isochrone A line on a chart connecting equal times of occurrence of an event. In a weather analysis, a sequence plotted on a map of the frontal positions at several…
1773. Isodop A contour of constant Doppler velocity values.
1774. Isodrosotherm A line connecting points of equal dew point temperature.
1775. Isoheight Same as a contour depicting vertical height of some surface above a datum plane.
1776. Isohel A line on a weather map connecting points receiving equal sunlight.
1777. Isohyet A line that connects points of equal rainfall.
1778. ISOL Isolate(d)
1779. Isolated A National Weather Service convective precipitation descriptor for a 10 percent chance of measurable precipitation (0.01 inch).
1780. ISOLD Isolated
1781. Isopleth A broad term for any line on a weather map connecting points with equal values of a particular atmospheric variable (temperature, dew point, etc.).
1782. Isotach A line connecting points of equal wind speed.
1783. Isotherm A line connecting points of equal temperature.
1784. Isothermal Having a constant temperature.
1785. isotope (I-soh-tope) A form of a chemical element in which the atoms have the same number of protons (part of the nucleus of an atom) but with a different number…
1786. Isotropic the property of being independent of direction. Isotropic radiation has the same intensity regardless of the direction of measurement.
1787. Issuance Time The time the product is transmitted.
1788. ITCZ Inter-tropical Convergence Zone. The region where the northeasterly and southeasterly tradewinds converge, forming an often continuous band of clouds or…
1789. ITWAS Integrated Terminal Weather System
1790. jökulhlaup a flood of meltwater from a glacial lake.
1791. J/kg Joules per kilogram, unit commonly used to represent CAPE and CIN.
1792. January Thaw A period of mild weather popularly supposed to recur each year in late January.
1793. Jet When air is sent at a high velocity through the carburetor, jets direct the fuel into the airstream.
1794. Jet fuel Includes both naphtha-type and kerosene-type fuels meeting standards for use in aircraft turbine engines.
1795. Jet Max ( or Jet Streak) A point or area of relative maximum wind speeds within a jet stream.
1796. Jet Streak Same as Jet Max; a point or area ("streak") of relative maximum wind speeds within a jet stream.
1797. Jet Stream (abbrev. JSTR) Relatively strong winds concentrated in a narrow stream in the atmosphere, normally referring to horizontal, high-altitude winds.
1798. Jet Stream Cirrus A loose term for filamentous cirrus that appears to radiate from a point in the sky, and exhibits characteristics associated with strong vertical wind…
1799. Jet Wind Speed Profile A vertical wind speed profile characterized by a relatively narrow current of high winds with slower moving air above and below.
1800. Jetty Pier or other structure built out into a body of water to influence the current or tide, or to protect a harbor or shoreline.