Editing Weather forecasting (section)

===Observation===
[[File:marestail.jpg|thumb|Marestail shows moisture at high altitude, signalling the later arrival of wet weather.]]
Along with pressure tendency, the condition of the sky is one of the more important parameters used to forecast weather in mountainous areas. Thickening of cloud cover or the invasion of a higher cloud deck is indicative of rain in the near future. High thin [[cirrostratus cloud]]s can create [[halo (optical phenomenon)|halo]]s around the [[sun]] or [[moon]], which indicates an approach of a [[warm front]] and its associated rain.<ref>{{cite magazine |url=https://books.google.com/books?id=KtkDAAAAMBAJ&pg=PA148|magazine=[[Popular Mechanics]] |page=148 |title=Make Your Own Weather Forecasts |author=Dennis Eskow |date=March 1983 |volume=159 |issue=3 |access-date=April 2, 2011}}</ref> Morning [[fog]] portends fair conditions, as rainy conditions are preceded by wind or clouds that prevent fog formation. The approach of a line of [[thunderstorm]]s could indicate the approach of a [[cold front]]. Cloud-free skies are indicative of fair weather for the near future.<ref>Mark Moore (March 25, 2009). [https://web.archive.org/web/20090325034756/http://www.nwac.us/education_resources/Field_forecasting.pdf "Field Forecasting – A Short Summary"]. Retrieved February 15, 2012.</ref> A [[Bar (tropical cyclone)|bar]] can indicate a coming tropical cyclone. The use of sky cover in weather prediction has led to various [[weather lore]] over the centuries.<ref name=Skywatch />