{"id":18970,"date":"2022-08-08T15:01:01","date_gmt":"2022-08-08T21:01:01","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=18970"},"modified":"2022-08-11T07:52:47","modified_gmt":"2022-08-11T13:52:47","slug":"fto-08-08-2022-a-brief-lull-before-heavy-rainfall-potential-returns","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=18970","title":{"rendered":"FTO 08-08-2022: A Brief Lull, Before Heavy Rainfall Potential Returns"},"content":{"rendered":"<p>Issue Date: Monday, August 8<sup>th<\/sup>, 2022<br>\nIssue Time: 3PM MDT<br>\nValid Dates: 8\/9 &ndash; 8\/23<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/threat_timeline-1.png\"><img loading=\"lazy\" class=\"alignnone size-large wp-image-18972\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/threat_timeline-1-1024x151.png\" alt=\"\" width=\"910\" height=\"134\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/threat_timeline-1-1024x151.png 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/threat_timeline-1-300x44.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/threat_timeline-1-768x113.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/threat_timeline-1.png 1207w\" sizes=\"(max-width: 910px) 100vw, 910px\"\/><\/a><\/p>\n<p>We are now approaching 60 days of precipitation somewhere across Colorado, as this busy <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 has taken few breaks thus far. Tomorrow looked to be the best chance for a dry day statewide, but at least <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> storms are now looking more probable. Thus, we will likely eclipse 60 straight days with rainfall!<\/p>\n<p>In this Outlook, we see a battle between some drier air (a rarity since mid-June!) and the restart of more monsoonal air being imported from the south, as shown in the water vapor image, below. With little in the way of large-scale dynamics, all eyes will be on the position of the monsoonal ridge. In the short-term, the ridge will strengthen overhead, temporarily blocking the import of fresh moisture. Thus, we expect reduced storm chances through Wednesday, though at least <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> activity is still expected over the higher terrain. But after this brief &ldquo;lull&rdquo;, at temporary <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> heavy rainfall will return by later this week (Event #2) warranting an Elevated Flood Threat. With weak steering flow, storms are likely to have a hard time making it off the higher terrain, thus only limited rainfall along with hot temperatures (3-5F above normal) are expected for most of eastern Colorado through this weekend.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/wv_markup-2.png\"><img loading=\"lazy\" class=\"wp-image-18973 aligncenter\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/wv_markup-2-1024x647.png\" alt=\"\" width=\"668\" height=\"422\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/wv_markup-2-1024x647.png 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/wv_markup-2-300x190.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/wv_markup-2-768x485.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/wv_markup-2.png 1081w\" sizes=\"(max-width: 668px) 100vw, 668px\"\/><\/a><\/p>\n<p>As shown in the GEFS <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> plumes, below, the battle between dry and moist air appears to favor the latter by early next week. With plenty of above normal moisture around most of western North America by that point, it appears to be the start of another prolonged busy period of heavy rainfall for our state. In addition to the usual monsoonal dynamics of southerly moisture transport, a couple of cool front disturbances could swing down from Canada, providing <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;boundary layer&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;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&amp;lt;br \/&amp;gt;&amp;lt;p&amp;gt;&amp;lt;span style=&amp;quot;color: #ffffff;&amp;quot;&amp;gt;The lower portion of the atmosphere that is directly influenced by the earth&amp;#039;s surface. Primarily, the boundary layer is driven by solar heating during the day and radiational cooling at night.&amp;lt;\/span&amp;gt;&amp;lt;\/p&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>boundary layer<\/span> support to fuel storms. There is significant model uncertainty at this time, but enough consensus exists to identify a fourth precipitation event beginning next Monday with an Elevated flood threat.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/gefs_pw.png\"><img loading=\"lazy\" class=\"alignnone size-large wp-image-18971\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/gefs_pw-1024x392.png\" alt=\"\" width=\"910\" height=\"348\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/gefs_pw-1024x392.png 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/gefs_pw-300x115.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/gefs_pw-768x294.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/gefs_pw.png 1448w\" sizes=\"(max-width: 910px) 100vw, 910px\"\/><\/a><\/p>\n<p>The identified precipitation events are described in more detail below.<\/p>\n<h4><strong>Event #1: Tuesday &ndash; Wednesday (August 9 &ndash; August 10)<\/strong><\/h4>\n<p><strong><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> To <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;widely scattered&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;10-25% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Widely Scattered<\/span> Higher Terrain Storms; <span style=\"color: #0000ff;\">No Apparent Flood Threat<\/span><\/strong><\/p>\n<p><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> to <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;widely scattered&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;10-25% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>widely scattered<\/span> storms are expected mainly over the southern and central higher terrain during the afternoon and evening hours. Max 30-min rainfall up to 0.4 inches looks possible on Tuesday, increasing to 0.6 inches by Wednesday. However, there is no apparent flood threat at this time.<\/p>\n<h4><strong>Event #2: Thursday &ndash; Friday (August 11 &ndash; August 12)<\/strong><\/h4>\n<p><strong><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> Higher Terrain Storms With Low-end <span style=\"color: #ff6600;\">Elevated Flood Threat<\/span><\/strong><\/p>\n<p>Fresh monsoonal moisture will increase storm coverage and maximum rain rates by Thursday. The best chances of storms will be over the central and northern higher terrain. Max 30-min\/60-min rain rates of 0.8 and 1.1 inches, respectively, could support a minor flood threat. Daily Bulletins will have a better look at these features as the depth of moisture recovery is determined.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e2.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-19022\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e2-300x203.png\" alt=\"\" width=\"880\" height=\"595\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e2-300x203.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e2-1024x692.png 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e2-768x519.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e2-1536x1038.png 1536w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e2.png 1772w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/a><\/p>\n<h4><strong>Event #3: Saturday &ndash; Sunday (August 13 &ndash; August 14)<\/strong><\/h4>\n<p><strong><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> To <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;widely scattered&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;10-25% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Widely Scattered<\/span> Mainly Higher Terrain Storms; <span style=\"color: #0000ff;\">No Apparent Flood Threat<\/span><\/strong><\/p>\n<p>Another period of dry air intrusion from the east should reduce storm coverage for all but the highest terrain. <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> activity still looks possible for the entire higher terrain from the WY to NM borders. However, max 30-min rain rates of up to 0.5 inches suggest flooding is not expected at this time.<\/p>\n<h4><strong>Event #4: Monday &ndash; Thursday (August 15 &ndash; August 18)<\/strong><\/h4>\n<p><strong><span style=\"color: #ff6600;\">Elevated Flood Threat<\/span> At Least For Higher Terrain With Some Spillover Likely Onto Plains<\/strong><\/p>\n<p>Things turn interesting by Monday, when a fresh pulse of monsoonal moisture looks to increase <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> to above 1 inch for a prolonged duration. Additionally, one or more cool front could drop south out of Canada, further enhancing storm coverage.<\/p>\n<p>Although there is significant uncertainty, it currently appears that mainly higher terrain storm on Monday will give way to 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> storms by Tuesday and Wednesday. Any cool front presence will allow storms to move off the higher terrain and sustain a 3-6 hour duration threat of heavy rainfall. At this time, given the very long lead time, an Elevated flood threat looks appropriate. However, more details will be available in the next Outlook, which could support an increase to a High threat.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e4.jpg\"><img loading=\"lazy\" class=\"aligncenter wp-image-19024\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e4-300x203.jpg\" alt=\"\" width=\"880\" height=\"597\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e4-300x203.jpg 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e4-1024x694.jpg 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e4-768x521.jpg 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e4-1536x1041.jpg 1536w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/08\/FTO_20220808_e4.jpg 1782w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Monday, August 8th, 2022 Issue Time: 3PM MDT Valid Dates: 8\/9 &ndash; 8\/23 We are now approaching 60 days of precipitation somewhere across Colorado, as this busy <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 has taken few breaks thus far. Tomorrow looked to be the best chance for a dry day statewide, but at least <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> storms are [&hellip;]<\/p>","protected":false},"author":4,"featured_media":0,"comment_status":"closed","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\/18970"}],"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=18970"}],"version-history":[{"count":5,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/18970\/revisions"}],"predecessor-version":[{"id":19025,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/18970\/revisions\/19025"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=18970"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=18970"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=18970"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}