{"id":16049,"date":"2021-09-12T09:51:31","date_gmt":"2021-09-12T15:51:31","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=16049"},"modified":"2021-09-12T09:51:31","modified_gmt":"2021-09-12T15:51:31","slug":"ftb-09-12-2021-scattered-storms-return-a-couple-severe-storms-possible-east","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=16049","title":{"rendered":"FTB 09-12-2021: Scattered Storms Return &#038; A Couple Severe Storms Possible East"},"content":{"rendered":"<p>Issue Date: Sunday, September 12th, 2021<br>\nIssue Time: 9:50AM MDT<\/p>\n<p><em>&mdash; Flooding is&nbsp;<\/em><strong><em>NOT&nbsp;<\/em><\/strong><em>expected today<\/em><\/p>\n<p>With the High suppressed to our south and a few shortwaves moving through the flow, the 500mb pattern has become 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> across the state this morning. This more westerly flow aloft will allow another <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>, marked below, to move across the state and increase mid-level lift for <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> storm development. In the wake of yesterday&rsquo;s <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>, a weak cold front has pushed through the eastern plains. With a slight increase in overall moisture, upslope flow, and uptick in lift from 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>, <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 expected to develop over the northern and central mountains by midday. As these storms are steered into the adjacent eastern plains, they should encounter a little deeper surface moisture along with some marginal <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;shear&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Local variation of the wind, either in the horizontal or vertical direction.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>shear<\/span>. This should allow the storms to expand in both coverage and intensity over the border counties, and one or two severe storms may be possible. The main threats from these severe storms would be large hail and strong <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;outflow&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A cool pool of air that results when a thunderstorm downdraft reaches the surface and spreads horizontally.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>outflow<\/span> winds.<\/p>\n<p>Steering flows do look to be a little slower than yesterday, which should help encourage higher local accumulations from the storms today. However, less surface moisture back to the west means that storms will likely produce more of a wind threat than heavy rainfall over the mountains and immediate adjacent plains. Although, <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;dew points&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;The temperature to which a given air parcel must be cooled (at constant pressure and water vapor content) in order for saturation to occur.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>dew points<\/span> over the far eastern plains should remain in the low to mid-50Fs, steering flow should be quick enough to keep rainfall rates just below flood threat criteria. Therefore, flooding is not expected today.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-16051\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210912.png\" alt=\"\" width=\"750\" height=\"467\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210912.png 1318w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210912-300x187.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210912-768x478.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/09\/wv_20210912-1024x637.png 1024w\" sizes=\"(max-width: 750px) 100vw, 750px\"\/><\/p>\n<h3><strong>Today&rsquo;s Flood Threat Map<\/strong><\/h3>\n<p>For more information on today&rsquo;s flood threat, see the map below. If there is a threat, hover over the threat areas for more details, and click on burn areas to learn more about them. For Zone-Specific forecasts, scroll below the threat map.<br><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/No_Flood_Threat_2021.png\"><img loading=\"lazy\" class=\"size-full wp-image-13663 aligncenter\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/No_Flood_Threat_2021.png\" alt=\"\" width=\"768\" height=\"576\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/No_Flood_Threat_2021.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/No_Flood_Threat_2021-300x225.png 300w\" sizes=\"(max-width: 768px) 100vw, 768px\"\/><\/a><\/p>\n<h3><strong>Zone-Specific Forecasts:<\/strong><\/h3>\n<h4><strong>Front Range, Central Mountains, Northern Mountains &amp; Northwest Slope:<\/strong><\/h4>\n<p>Cooler afternoon temperatures are forecast today with storms kicking of just after noon favoring the Front Range and Northern Mountains for development. Similar to yesterday, storms should pulse in intensity as they develop and fairly quickly dissipate or move out of the area. Max 1-hour rain rates up to 0.25 inches will be possible. In addition to rainfall, storms will likely produce gusty <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;outflow&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A cool pool of air that results when a thunderstorm downdraft reaches the surface and spreads horizontally.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>outflow<\/span> winds, especially over the Front Range. Flooding is NOT expected today.<br>\nPrimetime: 12:30PM to 9PM<strong>&nbsp;<\/strong><\/p>\n<h4><strong>Northeast Plains, Southeast Plains, Urban Corridor, Raton Ridge &amp; Palmer Ridge:<\/strong><\/h4>\n<p>As storms move east and off the mountains, they will begin to encounter slightly higher surface moisture. This should allow storms to increase in intensity, especially east of I-25. Over the adjacent plains (Urban Corridor), best coverage of the stronger storms will be north, especially along the Palmer Ridge. Max 1-hour rain rates up to 0.50 inches will be possible. South, max 1-hour rain rates up to 0.20 inches will be possible.<\/p>\n<p>A couple marginal severe storms may be possible this evening as storms make their way into the far eastern plains with the main threats being strong <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;outflow&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A cool pool of air that results when a thunderstorm downdraft reaches the surface and spreads horizontally.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>outflow<\/span> winds (50 to 55 mph) and large hail (1.25 inches). Best chance for this to happen will be north of southern Kiowa County border. Max 1-hour rain rates up to 1.50 inches will be possible with the stronger storms that develop, and storm intensity should begin to drop off around 9PM. However, some showers may linger&nbsp;overnight. Flooding is NOT expected today.<br>\nPrimetime: 2PM to 1:30AM<\/p>\n<h4><strong>Grand Valley, San Juan Mountains, Southeast Mountains, San Luis Valley &amp; Southwest Slope:<\/strong><\/h4>\n<p>It&rsquo;s expected to remain dry over the lower elevations of these forecast zones today with <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> storm development over the San Juan and Southeast Mountains this afternoon. Best chance for measurable rainfall will be along and near 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> where <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> storm totals up to 0.20 inches will be possible. High temperatures will drop into the upper 80Fs (lower elevations) with 70Fs for the mountain valleys. Flooding is NOT expected.<\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Sunday, September 12th, 2021 Issue Time: 9:50AM MDT &mdash; Flooding is&nbsp;NOT&nbsp;expected today With the High suppressed to our south and a few shortwaves moving through the flow, the 500mb pattern has become 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> across the state this morning. This more westerly flow aloft will allow another <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>, marked below, to move across [&hellip;]<\/p>","protected":false},"author":8,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[6],"tags":[],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/16049"}],"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=16049"}],"version-history":[{"count":2,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/16049\/revisions"}],"predecessor-version":[{"id":16053,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/16049\/revisions\/16053"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=16049"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=16049"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=16049"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}