{"id":15286,"date":"2021-08-01T10:58:46","date_gmt":"2021-08-01T16:58:46","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=15286"},"modified":"2021-08-02T07:37:45","modified_gmt":"2021-08-02T13:37:45","slug":"spm-08-01-2021-torrential-rain-across-southeast-colorado-heavy-rain-over-western-slope-as-well","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=15286","title":{"rendered":"SPM 08-01-2021: Torrential Rain Across Southeast Colorado; Heavy Rain Over Western Slope As Well"},"content":{"rendered":"<p>Issue Date: Sunday, August 1st, 2021<br>\nIssue Time: 11AM MDT<\/p>\n<h3>Summary:<\/h3>\n<p>The long awaited intense rainfall event finally came and went on Saturday, and generally speaking, lived up to its expectations. By far the most intense rainfall occurred over southeast Colorado, generally along the I-25 corridor south of Colorado Springs and eastward, along and south of the Arkansas River. Extremely efficient tropical-style rainfall from copious moisture overcame a lack of instability to provide <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> areas with at least 2 inches of rainfall. However, <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> pockets received more than that. Much more. The highest reliable observation came in from near Pueblo with 5.03 inches! A <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;CoCoRaHS&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;&amp;lt;strong&amp;gt;Co&amp;lt;\/strong&amp;gt;mmunity &amp;lt;strong&amp;gt;Co&amp;lt;\/strong&amp;gt;llaborative &amp;lt;strong&amp;gt;Ra&amp;lt;\/strong&amp;gt;in, &amp;lt;strong&amp;gt;H&amp;lt;\/strong&amp;gt;ail, and &amp;lt;strong&amp;gt;S&amp;lt;\/strong&amp;gt;now Network, a volunteer network of precipitation observers across the country&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>CoCoRaHS<\/span> observer east of Colorado City (between Pueblo and Walsenburg) reported 4.01 inches. <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;numerous&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;40-60% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Numerous<\/span> other reports in the 3-4 inch range also came in from El Paso, Las Animas, Baca and Pueblo counties. As of 10:30AM, eleven reports showed above 3 inches of rain. The highest estimated rainfall was from Baca County where up to 7 inches is shown! However, that area is one of the more difficult parts of the state to estimate because radar beams from various <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;NWS&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;National Weather Service&lt;\/div&gt;\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>NWS<\/span> radars measure storms very high above the ground, often leading to overestimates. On the other hand, yesterday&rsquo;s warm coalescence rainfall actually led to the underestimate of almost all high-end rainfall amounts. See the table below showing that 25 of the highest 33 <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;CoCoRaHS&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;&amp;lt;strong&amp;gt;Co&amp;lt;\/strong&amp;gt;mmunity &amp;lt;strong&amp;gt;Co&amp;lt;\/strong&amp;gt;llaborative &amp;lt;strong&amp;gt;Ra&amp;lt;\/strong&amp;gt;in, &amp;lt;strong&amp;gt;H&amp;lt;\/strong&amp;gt;ail, and &amp;lt;strong&amp;gt;S&amp;lt;\/strong&amp;gt;now Network, a volunteer network of precipitation observers across the country&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>CoCoRaHS<\/span> reports were underestimated by our gridded products, some significantly. So, 7 inches is certainly not out of the question.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/cocorahs_bias_20210801.png\"><img loading=\"lazy\" class=\"size-full wp-image-15297 aligncenter\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/cocorahs_bias_20210801.png\" alt=\"\" width=\"789\" height=\"546\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/cocorahs_bias_20210801.png 789w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/cocorahs_bias_20210801-300x208.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/cocorahs_bias_20210801-768x531.png 768w\" sizes=\"(max-width: 789px) 100vw, 789px\"\/><\/a><\/p>\n<p>In terms of the hydrologic response, <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;numerous&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;40-60% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>numerous<\/span> flood reports came in from southeast Colorado. In Baca County, where the highest rainfall in the state probably occurred, a report of 3 feet of water overtopping a road was received from east of Campo. Vehicles were reported stranded in flood water near Colorado Springs. Many reports of flooded roads came in from Pueblo. A long stretch of washed out road was reported south of Walsenburg just west of I-25. In all, runoff trickled into the Fountain Creek, Saint Charles River, Hardscrabble Creek, Huerfano River among other smaller creeks and tributaries to cause a flood wave on the Arkansas River that went from about 600 cfs to over 4,500 cfs in a matter of hours (see below). It is possible that even higher flows will occur downstream in the coming hours as additional sub-basins downstream chip in their share.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/arkansas_spike.png\"><img loading=\"lazy\" class=\"size-large wp-image-15298 aligncenter\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/arkansas_spike-1024x598.png\" alt=\"\" width=\"910\" height=\"531\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/arkansas_spike-1024x598.png 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/arkansas_spike-300x175.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/arkansas_spike-768x449.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/arkansas_spike.png 1203w\" sizes=\"(max-width: 910px) 100vw, 910px\"\/><\/a><\/p>\n<p>Along and 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>, <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;numerous&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;40-60% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>numerous<\/span> reports of heavy rainfall above 1 inch were received from Rio Blanco, Garfield and Gunnison counties. At least two reports of debris slides and mud flows were received as of this morning. One, from Poncha Pass where Highway 285 was blocked. Another from just outside of Telluride where a &ldquo;large&rdquo; mudflow forced the closure of Highway 145.<\/p>\n<p>Finally, it was another active day for fire burn areas across the state. Possibly for the first day thus far, all six fire burns were under a <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;flash flood&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;flash flooding can refer to usually dry areas becoming rapidly inundated with water, or rapid water level rises on streams, creeks, or rivers beyond flood stage; typically caused by heavy rainfall, but can also be caused by meltwater&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Flash Flood<\/span> <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Warning&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 weather warning is issued when a specific weather event is imminent or occurring&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Warning<\/span> at some point on Saturday afternoon. The most severe outcomes were likely over the Spring Creek and Pine Gulch burns. Over Spring Creek, at least 1.5 inches of rain fell resulting in Highway 421 being overtopped for &ldquo;hundreds of yards&rdquo;. Meanwhile, over Pine Gulch, storm chaser Reed Timmer filmed an impressive mud flow on its northeast side. A stone&rsquo;s throw away on the southwest side of the burn, addition mud flows resulted in evacuation orders for downstream neighborhoods.<\/p>\n<p>In short, the <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> of 2021 rages on.<\/p>\n<p>For estimates of precipitation in your area, please check our State Precipitation Map below.<\/p>\n<h4 class=\"collapseomatic \" id=\"id6a1bb499ebf06\" tabindex=\"0\" title=\"Click Here For Map Overview\">Click Here For Map Overview<\/h4><div id=\"target-id6a1bb499ebf06\" class=\"collapseomatic_content \">\nThe map below shows radar-estimated, rainfall gage-adjusted Quantitative Precipitation Estimates (<span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;QPE&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;&amp;lt;strong&amp;gt;Q&amp;lt;\/strong&amp;gt;uantitative &amp;lt;strong&amp;gt;P&amp;lt;\/strong&amp;gt;recipitation &amp;lt;strong&amp;gt;E&amp;lt;\/strong&amp;gt;stimate; an estimate of the amount of precipitation that has fallen at a particular location or across a region based on several different data sources, such as radar or satellite; QPE is often calculated using remotely-sensed data sources&lt;\/div&gt;\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>QPE<\/span>) across Colorado. The map is updated daily during the operational season (May 1 &ndash; Sep 30) by 11AM. The following six layers are currently available: 24-hour, 48-hour and 72-hour total precipitation, as well as maximum 1-hour, 2-hour and 6-hour precipitation over the past 24 hour period (to estimate where <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;flash flooding&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;flash flooding can refer to usually dry areas becoming rapidly inundated with water, or rapid water level rises on streams, creeks, or rivers beyond flood stage; typically caused by heavy rainfall, but can also be caused by meltwater&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>flash flooding<\/span> may have occurred). The accumulation ending time is 7AM of the date shown in the bottom right corner. Also shown optionally are vulnerable fire burn areas (post 2012), which are updated throughout the season to include new, vulnerable burn areas. The home button in the top left corner resets the map to the original zoom.<br><\/div>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/Screenshot-2021-08-02-073438.png\"><img loading=\"lazy\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/Screenshot-2021-08-02-073438.png\" alt=\"\" width=\"932\" height=\"607\" class=\"aligncenter size-full wp-image-15303\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/Screenshot-2021-08-02-073438.png 932w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/Screenshot-2021-08-02-073438-300x195.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/08\/Screenshot-2021-08-02-073438-768x500.png 768w\" sizes=\"(max-width: 932px) 100vw, 932px\"\/><\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Sunday, August 1st, 2021 Issue Time: 11AM MDT Summary: The long awaited intense rainfall event finally came and went on Saturday, and generally speaking, lived up to its expectations. By far the most intense rainfall occurred over southeast Colorado, generally along the I-25 corridor south of Colorado Springs and eastward, along and south [&hellip;]<\/p>","protected":false},"author":4,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[4],"tags":[],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/15286"}],"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\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=15286"}],"version-history":[{"count":4,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/15286\/revisions"}],"predecessor-version":[{"id":15305,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/15286\/revisions\/15305"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=15286"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=15286"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=15286"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}