[DOC] [TLE] Weather Map Symbols, Abbreviations, and Features - 2004 L ... [PAR] Weather Map Symbols, Abbreviations, and Features ... Center pressures (on 
Surface Maps) ... and Valid Time indicates the date and hour when the conditions 
shown are .... Two or three horizontal parallel lines indicate fog or heavy fog. [DOC] [TLE] Chapter 3: Weather Map [PAR] Station Model and Weather Maps.  Pressure as ... weather conditions. ... It is 
useful to examine horizontal pressure differences across space.  Pressure maps 
depict isobars, lines of equal pressure. ... Wind speeds are indicated in units of 
knot. 5. 10 .... In this example, a low-level jet is seen flowing parallel to the cold 
front. [DOC] [TLE] Surface Weather Analysis Chart [PAR] Because many of the surface weather maps display weather conditions at a ... 
that may appear on the surface chart are usually produced at 3 hourly intervals (
0000 UTC, .... lines to depict the features of the horizontal pressure field at mean 
sea level. ... The winds tend to parallel the isobars, with low pressure to the left of 
the... [DOC] [TLE] Weather front - Wikipedia [PAR] A weather front is a boundary separating two masses of air of different densities, 
and is the ... Air mass classification involves three letters. .... Occluded fronts are 
indicated on a weather map by a purple line with alternating ... or devolve into 
shear lines, but they can transform into a cold or warm front if conditions aloft 
change. [DOC] [TLE] Surface weather analysis - Wikipedia [PAR] Surface weather analysis is a special type of weather map that provides a view of 
weather .... Movement is due to the pressure gradient force (horizontal 
differences in ... Occluded fronts are indicated on a weather map by a purple line 
with ... into shear lines, but can change into a cold or warm front if conditions aloft 
change. [DOC] [TLE] Weather Fronts - OK-First - Mesonet [PAR] The slope of a typical cold front is 1:100 (vertical to horizontal). ... Cold fronts can 
be associated with squall lines (a line of strong thunderstorms parallel to and 
ahead of the front). ... Cold fronts almost always are easier to locate on a weather 
map than are warm fronts, primarily ... Figure 3 - Side View of a Typical Warm 
Front... [DOC] [TLE] Weather Maps - University of Denver [PAR] Mar 2, 2003 ... The weather map, analysis chart or synoptic chart shows isobars (contours .... in 
the lower parts, below 3 km, say, and is affected by surface conditions. ... the air, 
p the pressure, and x the horizontal distance normal to the isobars. ..... Two lines 
represent a light fog, and if the lines are broken the fog is patchy. [DOC] [TLE] Meteorology/Everyday Weather - Science Olympiad Student Center ... [PAR] Feb 24, 2016 ... 7.2.2 How To read weather maps/satellite imagery; 7.2.3 Station Models .... This 
air is very dry making surface conditions in these regions very arid. .... air flow 
parallel on both sides; doesn't move; widespread clouds; Precipitation light ..... 
the horizontal lines represent isobars, or lines of constant pressure. [DOC] [TLE] A Detailed List of All Weather Symbols and Their Exact Meanings [PAR] Aug 30, 2016 ... Weather maps have been used since ancient times to represent various .... of 
three horizontal, parallel lines is drawn in front of the sun weather... [DOC] [TLE] Weather radar - Wikipedia [PAR] Weather radar, also called weather surveillance radar (WSR) and Doppler 
weather radar, is a .... 3 cm X-band radar is used only for short-range units, and 1 
cm Ka-band ... The horizontal distance from station to target is calculated simply 
from the ...... As such, fine line patterns within weather radar imagery, associated 
with... [DOC] [TLE] How to Read Weather Maps  About MetService [PAR] Weather maps as they appear on TV, in a newspaper or here are called ... Those 
plain lines that curve across the map are called isobars (iso = equal, bar = 
pressure). They join together places with the same mean sea level

Question: On a weather map, 3 horizontal & parallel lines indicate this weather condition
Answer: fog