{"id":10877,"date":"2019-09-18T08:45:11","date_gmt":"2019-09-18T14:45:11","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=10877"},"modified":"2019-09-18T08:45:11","modified_gmt":"2019-09-18T14:45:11","slug":"ftb-09-18-2019-dry-air-moves-in-behind-the-trough-with-slightly-cooler-high-temperatures-for-wednesday","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=10877","title":{"rendered":"FTB 09-18-2019: Dry Air Moves in Behind the Trough with Slightly Cooler High Temperatures for Wednesday"},"content":{"rendered":"<p>Issue Date: Wednesday, September 18th, 2019<br>\nIssue Time: 8:45AM MDT<\/p>\n<p><em>&mdash; Flooding is <strong>NOT <\/strong>expected today<\/em><\/p>\n<p>Much drier air has moved over the state, which is shown by all the yellow in the water vapor imagery below. Not surprisingly, <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;PW&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;(Stands for: Precipitable Water) The total atmospheric water vapor contained in a vertical column of the atmosphere. It is typically measured in inches, and anomalously (deviation from normal) high values of precipitable water generally correlate to heavy rainfall potential.&lt;\/div&gt;\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>PW<\/span> has dropped to 0.55 to 0.60 inches at Grand Junction and Denver, respectively. Southwest flow aloft, which will turn more westerly this evening, will keep the drier air mass in place. Thus, not much afternoon shower and thunderstorm activity is expected with the minimal residual moisture in the atmosphere. The morning cloud cover over the western high terrains hints there is some pockets of moisture still over the mountains. So the best chance for an <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;isolated&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;less than 10% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>isolated<\/span> weak shower or thunderstorm will be over the mountains favoring the Front Range as this plume is advected to the northeast. Flooding is not forecast.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2019\/09\/wv_20190918.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-10878\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2019\/09\/wv_20190918.png\" alt=\"\" width=\"600\" height=\"409\"\/><\/a><\/p>\n<h3><strong>Today&rsquo;s Flood Threat Map<\/strong><\/h3>\n<p>For more information on today&rsquo;s flood threat, see the map below. For Zone-Specific forecasts, scroll below the map.<br><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2019\/05\/FTB_No_Flood_Threat_2019.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-8803\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2019\/05\/FTB_No_Flood_Threat_2019.png\" alt=\"\" width=\"880\" height=\"580\"\/><\/a><\/p>\n<h3><strong>Zone-Specific Forecasts:<\/strong><\/h3>\n<h4><strong>Central Mountains, Northern Mountains, San Juan Mountains, Front Range, Southeast Mountains, Urban Corridor:<\/strong><\/h4>\n<p>Best chance for rainfall today will be over the high terrains where pockets of residual moisture remain intact. While most storms will stop at producing just cloud cover and <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;virga&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Wisps or streaks of precipitation falling out of a cloud that evaporate before reaching the surface. Virga can cause strong, but short-lived, localized winds (dry microburst).&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>virga<\/span>, a couple storms may produce light accumulations. Best chance for rainfall will be over the Front Range where totals up to 0.2 inches will be possible with the stronger storms. Most other storms will produce under 0.1 inches across the mountains. Activity may spill into the Urban Corridor this afternoon with the flow aloft (to the NE), but storms are expected to quickly dissipate. Max 1-hour rain rates up to 0.1 inches will be possible along with brief <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;outflow&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A cool pool of air that results when a thunderstorm downdraft reaches the surface and spreads horizontally.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>outflow<\/span> gusts.<\/p>\n<p>Primetime: 2PM to 8PM<\/p>\n<h4><strong>Northwest Slope, Grand Valley, Southwest Slope, San Luis Valley, Raton Ridge, Palmer Ridge, Southeast Plains, Northeast Plains:<\/strong><\/h4>\n<p>Slightly cooler temperatures are anticipated today behind a weak cold front that moved through overnight. The cold front is currently over the Southeast Plains and has stalled out back to the west. With low <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;dew points&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;The temperature to which a given air parcel must be cooled (at constant pressure and water vapor content) in order for saturation to occur.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>dew points<\/span> across these regions, rainfall is not anticipated this afternoon. Surface winds over western Colorado may pick up to 10-15 mph (from the southwest) as the next <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;trough&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;An elongated area of relatively low atmospheric pressure; the opposite of a ridge.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>trough<\/span> begins to approach this afternoon. <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;critical fire weather&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;&amp;lt;!-- wp:paragraph {&amp;quot;textColor&amp;quot;:&amp;quot;white&amp;quot;} --&amp;gt;\n&amp;lt;p class=&amp;quot;has-white-color has-text-color&amp;quot;&amp;gt;weather conditions especially conducive to the formation of wildfires; typically strong winds, low relative humidity, and atmospheric instability&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Critical fire weather<\/span> is not forecast, but some pockets of elevated fire weather are anticipated.<\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Wednesday, September 18th, 2019 Issue Time: 8:45AM MDT &mdash; Flooding is NOT expected today Much drier air has moved over the state, which is shown by all the yellow in the water vapor imagery below. Not surprisingly, <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;PW&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;(Stands for: Precipitable Water) The total atmospheric water vapor contained in a vertical column of the atmosphere. It is typically measured in inches, and anomalously (deviation from normal) high values of precipitable water generally correlate to heavy rainfall potential.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>PW<\/span> has dropped to 0.55 to 0.60 inches at Grand Junction and Denver, respectively. Southwest flow [&hellip;]<\/p>","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[6],"tags":[],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/10877"}],"collection":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=10877"}],"version-history":[{"count":1,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/10877\/revisions"}],"predecessor-version":[{"id":10879,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/10877\/revisions\/10879"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10877"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10877"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10877"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}