{"id":12448,"date":"2020-07-23T15:10:42","date_gmt":"2020-07-23T21:10:42","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=12448"},"modified":"2020-07-27T12:38:04","modified_gmt":"2020-07-27T18:38:04","slug":"fto-07-23-2020-prolonged-monsoon-moisture-surge-to-cause-widespread-rainfall-and-flooding-issues","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=12448","title":{"rendered":"FTO 07-23-2020: Prolonged Monsoon Moisture Surge to Cause Widespread Rainfall and Flooding Issues"},"content":{"rendered":"<p>Issue Date: Thursday,&nbsp;July 23rd, 2020<br>\nIssue Time: 3:10PM MDT<br>\nValid Dates:&nbsp;7\/24&ndash; 8\/7<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-12449\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO-20200723.png\" alt=\"\" width=\"880\" height=\"133\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO-20200723.png 1153w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO-20200723-300x45.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO-20200723-768x116.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO-20200723-1024x155.png 1024w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/p>\n<p>A nice <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> moisture plume has set up over the state the last couple days, and it has been reinforced by a <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;shortwave&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A disturbance in the mid or upper part of the atmosphere which induces upward motion ahead of it.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>shortwave<\/span>\/weak Low over California. The location of the High has really funneled a lot of moisture into the state, and on and off shortwaves have helped spark more <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;widespread&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;greater than 60% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>widespread<\/span> and intense rainfall. Tomorrow, the Low will begin to eject to the northeast, in similar fashion to yesterday&rsquo;s <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;shortwave&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A disturbance in the mid or upper part of the atmosphere which induces upward motion ahead of it.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>shortwave<\/span>, with the incoming <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> marked below. Shortly after, an elongated High will set up to our east, and with more <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;zonal&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;refers to the east-west direction; usually used to describe atmospheric flow that roughly follows lines of latitude&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>zonal<\/span> flow to our north and another low dropping into CA, Colorado will be placed under favorable flow for a subtropical moisture tap through early next week. Additionally, a tropical depression might get ingested to flow, which would bring more mid-level energy to the state by early next week.<\/p>\n<p>Wednesday, the High will be located over Colorado, so expecting the atmosphere to dry out a bit and give us a break from the all the rain. The northwesterly flow aloft over eastern Colorado could send some disturbances through the flow, which would likely return moisture to the state for afternoon and evening storms. Expecting that pattern to hold through the weekend, which could also pull enough moisture across the southern mountains for afternoon <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;scattered&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;25-40% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>scattered<\/span> storms.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-12452 size-full\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/wv-20200723.png\" alt=\"\" width=\"851\" height=\"418\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/wv-20200723.png 851w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/wv-20200723-300x147.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/wv-20200723-768x377.png 768w\" sizes=\"(max-width: 851px) 100vw, 851px\"\/><\/p>\n<p>One thing to point out in the moisture plumes below is the large spread both east and west by about Saturday. Further south, there is a clear upward trend in <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> for this period, so the images below are showing uncertainty with how far north the higher <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> values will make it. With <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> well over an inch, an Elevated threat has been issued for the next three days. For Monday and Tuesday, the strong upward trend further south is very pronounced, so a High flood threat has been issued. Slower steering winds also raise concerns for recent burn areas. Please stay tuned to the FTB this weekend, especially if you&rsquo;re planning on camping or hiking.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-12451\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/PW_20200723.png\" alt=\"\" width=\"880\" height=\"301\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/PW_20200723.png 1199w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/PW_20200723-300x103.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/PW_20200723-768x263.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/PW_20200723-1024x350.png 1024w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/p>\n<p>The Colorado reservoir storage maps were released by NRCS yesterday. The most notable feature in the map is the large downward trend over the last couple of months in the Upper Rio Grande Basin. Reservoirs now sit at about 50% capacity and we haven&rsquo;t even added in July\/August water use. Since October 2001, only about 5 years have had above &ldquo;departure from average storage&rdquo;. Unsure how this relates to obligated releases downstream, but I&rsquo;m sure that plays a part.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-12453\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/co_resv_pct-1.gif\" alt=\"\" width=\"880\" height=\"625\"\/><\/p>\n<h3><strong>Event #1:<\/strong> <strong>Friday <\/strong><strong>&ndash;<\/strong><strong> Tuesday <\/strong><strong>(7\/2<\/strong><strong>4 <\/strong><strong>&ndash;<\/strong><strong> 7\/28<\/strong><strong>) <\/strong><\/h3>\n<p><span style=\"color: #ff0000;\"><strong>High<\/strong><\/span><strong>\/<span style=\"color: #ff6600;\">Elevated Threat<\/span>&nbsp;<\/strong>as the subtropical moisture takes hold of the state with plenty of shortwaves moving through the flow.<\/p>\n<p>Tomorrow, the Low will begin to eject to the northeast, in similar fashion to yesterday&rsquo;s <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;shortwave&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A disturbance in the mid or upper part of the atmosphere which induces upward motion ahead of it.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>shortwave<\/span>, with the incoming <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>.&nbsp;That means&nbsp;western Colorado will get to wake up to some cool, cloudy\/rainy conditions. The cloud cover should keep the thunderstorm threat low in the afternoon, but expect storms to return to the San Juan Mountains. As the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;shortwave&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A disturbance in the mid or upper part of the atmosphere which induces upward motion ahead of it.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>shortwave<\/span> moves to the northeast, an uptick in storms over northeast Colorado is also expected. With high moisture values in the area and increased lift, an Elevated flood threat has been issued. The increased moisture levels will continue through next week, and an upwards trend further south will cause a High elevated flood threat for Monday and Tuesday. Multiple rounds of rainfall could also cause increased runoff and make soils <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;unstable&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 atmosphere is considered unstable if it is conducive to air attempting to rise; the opposite of stable; an unstable atmosphere is necessary for thunderstorms&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>unstable<\/span>, so be sure to follow the FTB and SPM where we track that daily. While instability and upper dynamics may need to be assessed each day, slow steering winds should allow for some higher accumulations. Thus, the recent burn areas will also be watched closely over the next week. The most important feature to communicate is that heavy rainfall is expected to be <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;widespread&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;greater than 60% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>widespread<\/span> for this event. Follow the day to day details in the FTB.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-12525\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO_20200723_e1.png\" alt=\"\" width=\"880\" height=\"592\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO_20200723_e1.png 890w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO_20200723_e1-300x202.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO_20200723_e1-768x517.png 768w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/p>\n<h3><strong>Event #2: <\/strong><strong>Thursday<\/strong><strong> &ndash; <\/strong><strong>Saturday<\/strong><strong> (7\/<\/strong><strong>30<\/strong><strong> &ndash; <\/strong><strong>8\/1<\/strong><strong>)<\/strong><\/h3>\n<p><span style=\"color: #0000ff;\"><strong>No Apparent<\/strong><\/span> as weak moisture moves into eastern Colorado and across the southern border.<\/p>\n<p>At this time, the threat does not look as serious as this next week&rsquo;s <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;widespread&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;greater than 60% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>widespread<\/span>, heavy rainfall event. This is due to the placement of the high over the state with a weak ridging pattern. Northwest flow could push some weak fronts through the eastern plains, which always have the potential to return low-level moisture, and therefore, afternoon storms. Steering flow will be slow again, so unless there is a boundary for forcing over the plains, storms should stick close to the mountains. Additionally, <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;scattered&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;25-40% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>scattered<\/span> storms are anticipated across the southern border as some weak moisture is drawn up around the High. Be sure to stay tuned into this event as the details will evolve and change.<br><img loading=\"lazy\" class=\"aligncenter wp-image-12526\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO_20200723_e2.png\" alt=\"\" width=\"880\" height=\"592\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO_20200723_e2.png 891w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO_20200723_e2-300x202.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/07\/FTO_20200723_e2-768x516.png 768w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Thursday,&nbsp;July 23rd, 2020 Issue Time: 3:10PM MDT Valid Dates:&nbsp;7\/24&ndash; 8\/7 A nice <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> moisture plume has set up over the state the last couple days, and it has been reinforced by a <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;shortwave&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A disturbance in the mid or upper part of the atmosphere which induces upward motion ahead of it.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>shortwave<\/span>\/weak Low over California. The location of the High has really funneled a lot of moisture into the state, and on [&hellip;]<\/p>","protected":false},"author":8,"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\/12448"}],"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=12448"}],"version-history":[{"count":3,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/12448\/revisions"}],"predecessor-version":[{"id":12527,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/12448\/revisions\/12527"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=12448"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=12448"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=12448"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}