{"id":16229,"date":"2021-09-23T14:57:31","date_gmt":"2021-09-23T20:57:31","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=16229"},"modified":"2021-09-27T09:12:10","modified_gmt":"2021-09-27T15:12:10","slug":"fto-09-23-2021-warm-dry-through-the-weekend-with-precipitation-chances-returning-next-week","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=16229","title":{"rendered":"FTO 09-23-2021: Warm &#038; Dry Through the Weekend with Precipitation Chances Returning Next Week"},"content":{"rendered":"<p>Issue Date: Thursday,&nbsp;September 23rd, 2021<br>\nIssue Time:&nbsp;3PM MDT<br>\nValid Dates:&nbsp;9\/24 &ndash; 10\/8<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-16242\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923.png\" alt=\"\" width=\"880\" height=\"122\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923.png 2396w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923-300x42.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923-768x106.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923-1024x142.png 1024w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/p>\n<p>Despite a cold front moving through the state tonight, there will be little change in the overall availability of moisture. So, at this time, not anticipating any meaningful post-frontal rainfall tomorrow, just a drop in overall temperatures a few degrees. The <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 our west (marked below) will likely become cut off from the main flow over the next 24-hours. This disturbance looks like it will linger to our southwest for the next several days as a ridging pattern builds over the area. Through this weekend, that ridging pattern should be the dominate weather feature and return above average temperatures and dry conditions to the state. There may be some breezy conditions over the northern mountains and eastern plains during this period, which could increase fire danger through early next week. It isn&rsquo;t until late Monday into Tuesday when the weather gets interesting again.<\/p>\n<p>It is likely that this <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;cutoff low&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;an upper-level low pressure system that has been &amp;quot;cut off&rdquo; from the prevailing winds that steer weather systems; cut-off lows typically become stationary or move very slowly, bringing prolonged periods of unsettled weather&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>cutoff Low<\/span>\/vorticity maximum will pull some subtropical moisture northward by early next week. This should increase the chances of precipitation by early next week across the southern high terrains, particularly west. 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> arrives by mid-week, extra dynamics may interact with a&nbsp;(potential) moisture surge over Colorado. Thus, Event #1 is extended into the first weekend of October.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-16244\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210923.png\" alt=\"\" width=\"800\" height=\"412\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210923.png 1452w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210923-300x155.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210923-768x396.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210923-1024x528.png 1024w\" sizes=\"(max-width: 800px) 100vw, 800px\"\/><\/p>\n<p>There&rsquo;s a lot of uncertainty with Event #1 for a couple of reasons. One, it&rsquo;s hard to tell where the mid-level energy will move early next week and how much subtropical moisture it will help pull northward. Additionally, models are not in agreement with the strength or exact location of the next large 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> and its ability to tap into elevated moisture. This uncertainty within the forecast can be seen in the <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 by the separation of the gray lines (ensemble members) after this weekend.<\/p>\n<p>Generally speaking, there does look like there will be an overall increase in moisture both east and west with Event #1, but the magnitude of the <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> surge remains unknown. This places a lot of uncertainty in the QPF totals and placement of precipitation. Next Thursday could also get interesting over the Urban Corridor and adjacent plains as a cold front may slide south during the afternoon hours. At this time, there is No Apparent flood threat issued as it is unlikely, that this late in the season, decent instability will be able to build for more vigorous thunderstorms and higher rain rates. Nonetheless, Event #1 bears watching, so be sure to tune back into the FTO on Monday for the latest details.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-16243\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/PW_20210923.png\" alt=\"\" width=\"880\" height=\"304\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/PW_20210923.png 2122w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/PW_20210923-300x104.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/PW_20210923-768x266.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/PW_20210923-1024x354.png 1024w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/p>\n<h3><strong>Event #1:<\/strong> <strong>Tuesday<\/strong><strong> &ndash; <\/strong><strong>Saturday<\/strong><strong> (9\/2<\/strong><strong>8<\/strong><strong> &ndash; <\/strong><strong>10\/2<\/strong><strong>)<\/strong><\/h3>\n<h4><strong><span style=\"color: #0000ff;\">NO APPARENT <\/span>flood threat is issued <\/strong><strong>as a trough interacts with minimal subtropical moisture<\/strong><strong>.<\/strong><\/h4>\n<p>Currently, Event #1 is looking like there could be decent accumulation over the southwest corner of the state starting early next week. The magnitude of the moisture surge will directly affect the totals, but <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> areas of the San Juan Mountains could see up to 1 inch of precipitation, if the surge is strong enough. It dries out fairly quickly over the northwestern portion of the state with the arrival of 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>, but that&rsquo;s when the precipitation chances shift eastward. There&rsquo;s more uncertainty with QPF over the eastern portion of the state Thursday into the weekend. We&rsquo;ll continue to keep an eye on the event as Thursday shows some potential for thunderstorm development. It is likely that this will be more of a stratiform rainfall event due to the fact it is already October and instability typically begins to drop off. So, at this time there is No Apparent flood threat issued. As far as snowfall chances, only a handful of the GEFS members have snow falling over the mountains Wednesday into Thursday at this time.<br><img loading=\"lazy\" class=\"aligncenter wp-image-16294\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923_e1.png\" alt=\"\" width=\"880\" height=\"597\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923_e1.png 1782w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923_e1-300x203.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923_e1-768x521.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/FTO_20210923_e1-1024x694.png 1024w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Thursday,&nbsp;September 23rd, 2021 Issue Time:&nbsp;3PM MDT Valid Dates:&nbsp;9\/24 &ndash; 10\/8 Despite a cold front moving through the state tonight, there will be little change in the overall availability of moisture. So, at this time, not anticipating any meaningful post-frontal rainfall tomorrow, just a drop in overall temperatures a few degrees. The <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 [&hellip;]<\/p>","protected":false},"author":8,"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\/16229"}],"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=16229"}],"version-history":[{"count":4,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/16229\/revisions"}],"predecessor-version":[{"id":16295,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/16229\/revisions\/16295"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=16229"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=16229"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=16229"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}