{"id":7509,"date":"2018-07-05T11:01:39","date_gmt":"2018-07-05T17:01:39","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=7509"},"modified":"2018-07-09T10:14:12","modified_gmt":"2018-07-09T16:14:12","slug":"fto-07-05-2018-the-first-breath-of-the-2018-monsoon","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=7509","title":{"rendered":"FTO 07-05-2018: The First Breath of the 2018 Monsoon"},"content":{"rendered":"<p>Issue Date: 7\/5\/2018<br>\nIssue Time: 11:10 AM<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/07\/Threat_Timeline_20180705.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-7510\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/07\/Threat_Timeline_20180705.png\" alt=\"\" width=\"880\" height=\"123\"\/><\/a><\/p>\n<p>This FTO period is very front-heavy, with two events in the first 5 days, and then no apparent events through the remainder of the period. With Event #1 designated as a High Flood Threat, and Event #2 designated as an Elevated Flood Threat, we&rsquo;re just going to dive straight into the discussion today, focusing on the key points surrounding the flood threats.<\/p>\n<p><span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;monsoon&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;a seasonal wind that brings moisture and rain to the region into which it blows; there is also a dry phase to monsoons, but popular usage refers only to the wet phase; these winds occur in many places around the world, and where they occur they are responsible for a majority of that location&rsquo;s annual precipitation&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Monsoon<\/span> season is drawing near, and the first real breath of the 2018 <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;monsoon&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;a seasonal wind that brings moisture and rain to the region into which it blows; there is also a dry phase to monsoons, but popular usage refers only to the wet phase; these winds occur in many places around the world, and where they occur they are responsible for a majority of that location&rsquo;s annual precipitation&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>monsoon<\/span> is the main culprit behind both Event #1 and Event #2. Highlighted in the water vapor image below are the large-scale features of note for this period; we will break them down with each individual event. Event #1 will begin on Friday, July 6th, as the broad upper-level High centered over the Great Plains shifts eastward with the approach of the upper-level <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> denoted by the purple &ldquo;#1&rdquo;. These features will funnel Pacific moisture across the southwestern US (green arrow) and into western Colorado, as well as make use of the residual moisture from the Gulf of Mexico already impacting the state today. This funneling of moisture will focus the bulk of shower\/thunderstorm activity along\/west of the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Continental Divide&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;the dividing line that separates the watersheds of the western and eastern United States; rivers west of the divide empty into the Pacific Ocean, while rivers east of the divide empty into the Atlantic Ocean or Gulf of Mexico&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Continental Divide<\/span>, with <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;precipitable water&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;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\"}]'>precipitable water<\/span> values well above normal across much of western Colorado. This deep moisture, combined with fairly weak steering flow, will bring the threat of heavy rain and slow-moving thunderstorms to susceptible terrain and sensitive burn scars, such as the 416 Fire, Burro Fire, and West Fork Complex Fire. There is enough potential for heavy rainfall, or extended periods of moderate rainfall, impacting these areas that the trigger has been pulled on a High Threat designation. Event #1 continues through Sunday, July 8th, when the upper-<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> will exit across the northern US, and the next upper-level <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> follows closely behind.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/07\/WV_20180705-1.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-7511 size-full\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/07\/WV_20180705-1.png\" alt=\"\" width=\"717\" height=\"478\"\/><\/a><\/p>\n<p>Event #2 begins immediately after Event #1, on Monday, July 9th, as the next upper-level <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> digs into the western US, forcing southwesterly flow to remain over the state and continuing the funnel of Pacific moisture into western Colorado. Event #2, just as Event #1, will be mainly a western Colorado event, but Event #2 will hold some potential for heavy rain along the Front Range and Southeast Mountains, extending eastward slightly to adjacent lower elevations. The upper-level <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> will exit the region across the northern Rockies late Tuesday\/early Wednesday (July 10th\/July 11th). A bit of uncertainty in the eventual evolution of Event #2 precludes the issuance of a high threat, but an Elevated Threat is warranted at this time.<\/p>\n<p>After Event #2, the remainder of this FTO period will see the upper-level ridge dominate the weather pattern over Colorado once again, resulting in hot temperatures and sparser, high-based thunderstorm activity. Diurnal showers\/thunderstorms over the higher terrain will be likely, as is typical of hot summer days in Colorado, with the potential for them to drift over adjacent lower elevations. No flood threat highlights are warranted at this time.<\/p>\n<h3><strong>Event #1: Friday (07-06-2018) through Sunday (07-08-2018)<\/strong><\/h3>\n<p><em><strong><span style=\"color: #ff0000;\">High Flood Threat<\/span><\/strong> from the first breath of Deep, Monsoonal Moisture<\/em><\/p>\n<p>The favorable position of an upper-level <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> to the west and an upper-level high centered over the central US will funnel Pacific moisture into western Colorado. This deep moisture will coincide with relatively weak steering flow, meaning that slow-moving thunderstorms capable of heavy rainfall will be a threat to susceptible terrain and sensitive burn scars, especially new burn scars like the 416 Fire and Burro Fire. Please monitor the daily FTB for more information regarding each specific day&rsquo;s flood threat.<\/p>\n<div style=\"position: relative;\"><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/07\/FTO_20180705_e1_snap.png\"><img loading=\"lazy\" class=\"alignnone wp-image-7554\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/07\/FTO_20180705_e1_snap.png\" alt=\"\" width=\"880\" height=\"567\"\/><\/a><\/div>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/05\/Legend.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-230\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/05\/Legend.png\" alt=\"Legend\" width=\"94\" height=\"158\"\/><\/a><\/p>\n<h3><strong>Event #2: Monday (07-09-2018) and Tuesday (07-10-2018)<\/strong><\/h3>\n<p><em><strong><span style=\"color: #ff6600;\">Elevated Flood Threat<\/span> <\/strong>as the Moisture Funnel Continues<\/em><\/p>\n<p>Following immediately on the heels of Event #1, Event #2 is more of the same, with the funnel of Pacific moisture continuing thanks to the second upper-level <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> positioning itself favorably. Just as Event #1, this is mainly an event for areas along\/west of the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Continental Divide&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;the dividing line that separates the watersheds of the western and eastern United States; rivers west of the divide empty into the Pacific Ocean, while rivers east of the divide empty into the Atlantic Ocean or Gulf of Mexico&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Continental Divide<\/span>, but a bit stronger steering flow to the east will allow for a few storms to impact the Front Range, Southeast Mountains, and adjacent lower elevations. Uncertainty in the eventual evolution of the event precludes Event #2 from being designated as a High Flood Threat, but the presence of deep moisture, instability, and relatively weak steering flow are enough to warrant the Elevated Flood Threat. We will continue to monitor Event #2, and the daily FTB&rsquo;s will provide up-to-date information.<\/p>\n<div style=\"position: relative;\"><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/07\/FTO_20180705_e2_snap.png\"><img loading=\"lazy\" class=\"alignnone wp-image-7555\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/07\/FTO_20180705_e2_snap.png\" alt=\"\" width=\"880\" height=\"562\"\/><\/a><\/div>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/05\/Legend.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-230\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/05\/Legend.png\" alt=\"Legend\" width=\"94\" height=\"158\"\/><\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: 7\/5\/2018 Issue Time: 11:10 AM This FTO period is very front-heavy, with two events in the first 5 days, and then no apparent events through the remainder of the period. With Event #1 designated as a High Flood Threat, and Event #2 designated as an Elevated Flood Threat, we&rsquo;re just going to dive [&hellip;]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[3],"tags":[],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/7509"}],"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\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7509"}],"version-history":[{"count":3,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/7509\/revisions"}],"predecessor-version":[{"id":7556,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/7509\/revisions\/7556"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7509"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7509"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7509"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}