{"id":8049,"date":"2018-08-14T09:24:04","date_gmt":"2018-08-14T15:24:04","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=8049"},"modified":"2018-08-15T07:38:05","modified_gmt":"2018-08-15T13:38:05","slug":"ftb-08-14-2018-flood-threat-returns-to-eastern-colorado","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=8049","title":{"rendered":"FTB 08-14-2018: Flood Threat Returns to Eastern Colorado"},"content":{"rendered":"<p>Issue Date: Tuesday, August 14th, 2018<br>\nIssue Time: 09:30AM MDT<\/p>\n<p><em>&mdash; A <strong>MODERATE <\/strong>flood threat has been issued for Southeast Mountains and portions of the Front Range, Urban Corridor, Palmer Ridge and Raton Ridge<\/em><\/p>\n<p><em>&mdash; A <strong>LOW <\/strong>flood threat has been issued for the Front Range, Southeast Mountains, Central Mountains, Urban Corridor, Palmer Ridge, Raton Ridge and portions of the Northeast and Southeast Plains<\/em><\/p>\n<p>Quite a lot of fog over the eastern plains this morning with some very dense fog in spots. This means the low-level moisture has returned as the upper-level low traversed eastward into Kansas over the last 24-hours. The fog should begin to breakup throughout the morning, which should increase visibility. However, smoke from wildfires will limit the usual crystal blue skies again this afternoon. Expecting similar smoke conditions to yesterday. Today, the 500mb high begins to rebuild over the desert southwest, which will return weak, northwesterly flow aloft. A vorticity max over Utah is expect to rotate around the high, which should bring a little extra energy to the state for 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> afternoon thunderstorm coverage. To our north, a passing <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> will also push 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> near our norther border, which will help enhance thunderstorm activity over the area even more. Overall, looking at an active day with the threat of thunderstorms returning to the Front Range and Southeast Mountains.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/08\/wv_20180814.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-8050\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/08\/wv_20180814.png\" alt=\"\" width=\"500\" height=\"403\"\/><\/a><\/p>\n<p>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> passes over western Colorado early this afternoon, it should help kick off the thunderstorm action a couple hours sooner than usual over the higher terrains. Looking at <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> showers and thunderstorms similar to yesterday with Grand Junctions <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;precipitable water&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;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\"}]'>Precipitable Water<\/span> (<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>) around 0.75 inches. I wouldn&rsquo;t be surprised if some of this moisture mixes out and rain rates drop off a bit from yesterday. This means thunderstorms that form today will again be capable of producing gusty winds and dangerous lightning. Increased cloud cover and integrated smoke will also help keep the high temperatures a bit cooler.<\/p>\n<p>The shortwaves arrive to eastern Colorado around peak heating this afternoon, which means stronger thunderstorms and increased coverage along the Front Range and Southeast Mountains for initiation. <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 at Denver this morning were over 1 inch and with storm motion slowly to the southeast around 15 mph, the flood threat returns. <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;outflow boundaries&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A surface boundary formed by the horizontal spreading of thunderstorm-cooled air. Outflow boundaries may intersect with each other or with other features (fronts, dry line, low-level jet) and initiate new convection. Brief strong winds are possible with outflow boundaries, and they can also persist for more than 24 hours.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Outflow boundaries<\/span> from earlier thunderstorms will likely help kick off more thunderstorm action in the moist environment, so a couple rounds of storms over one area will be possible. Storms are expected to move into the adjacent plains later this afternoon, but the far eastern plains look to remain <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;capped&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;The area where a parcel of air has negative buoyancy or sinks. The intensity of the cap is measured by its convective inhibition. If the cap is sufficiently large, it may prevent thunderstorms from forming at all.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>capped<\/span>. Therefore, the flood threat should be confined west of Highway 71. There is also a possibility of a couple of storms moving off the Cheyenne Ridge into northern Weld County, so the Low threat has been extended into that area.<\/p>\n<p>A Low flood threat has been issued for the eastern mountains and immediate adjacent plains. Burn areas will be need to be monitored closely as there is high confidence max 1-hour rain rates will exceed 0.5 inches\/hour for all larger thunderstorms. Most of the problematic burn scars are included in the smaller area of the Moderate flood threat, which should suffice. Threats today include mud flows and debris slides over the steeper terrains and <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> of small streams. A quick 0.5 inches in 30 minutes is possible over urban areas, and with impervious surfaces, flooding of low-lying intersections and streets is possible. Storms will end a few hours after sundown, though some showers may linger in the Southeast Mountains overnight.<\/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. For Zone-Specific forecasts, scroll below the map.<\/p>\n<div style=\"position: relative;\"><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/08\/FTB_20180814_snap.png\"><img loading=\"lazy\" class=\"alignnone wp-image-8055\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2018\/08\/FTB_20180814_snap.png\" alt=\"\" width=\"880\" height=\"498\"\/><\/a><\/div>\n<div><img loading=\"lazy\" class=\"alignright wp-image-135\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/04\/floodthreat_legend2.png\" alt=\"Flood Threat Legend\" width=\"275\" height=\"71\"\/><\/div>\n<p>&nbsp;<\/p>\n<h3><strong>Zone-Specific Forecasts:<\/strong><\/h3>\n<h4><strong>Northeast Plains, Southeast Plains, Urban Corridor, Raton Ridge, Southeast Mountains, Front Range, Palmer Ridge:<\/strong><\/h4>\n<p>Peak heating and the passage of a couple upper-level shortwaves coinciding will bring thunderstorms back to the eastern mountains and adjacent plains this afternoon. High low-level moisture has returned as well and with slower steering winds aloft, the flood threat returns. Instability and minimal <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> will create an environment capable of producing some severe hail (up to 1.5 inches) and damaging winds under the strongest thunderstorms. Max 1-hour rain rates up to 1 inch\/hour (north) and up to 1.25 inches\/hour (south) are achievable. Further south, 2 to 3 hour totals up to 1.75 inches are possible. Threats today include mud flows and debris slides over the steeper terrains and <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> of small streams. This is especially true near recent burn scars, so these should be monitored closely this afternoon. A quick 0.5 inches in 30 minutes is possible over urban areas and with impervious surfaces, flooding of low-lying intersections and streets is likely.<\/p>\n<p>Primetime: 1PM &ndash; 12AM<\/p>\n<p><strong>Northern Mountains, Northwest Slope, Grand Valley, Central Mountains, San Juan Mountains, San Luis Valley, Southwest Slope: <\/strong><\/p>\n<p>Similar setup to yesterday with rain rates dropping off a bit. Storm activity should be relatively <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> today and kick off a couple of hours sooner than usual with the passing <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> arriving from Utah. Valleys may see some light rain again today, but gusty winds are the more likely scenario. Small hail is also possible under the stronger storms over the San Juan Mountains. Max 1-hour rain rates up to 0.1 inches (north) and 0.3 inches (south) are possible. Flooding is not expected.<\/p>\n<p>Primetime: 12PM &ndash; 9PM<\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Tuesday, August 14th, 2018 Issue Time: 09:30AM MDT &mdash; A MODERATE flood threat has been issued for Southeast Mountains and portions of the Front Range, Urban Corridor, Palmer Ridge and Raton Ridge &mdash; A LOW flood threat has been issued for the Front Range, Southeast Mountains, Central Mountains, Urban Corridor, Palmer Ridge, Raton [&hellip;]<\/p>","protected":false},"author":8,"featured_media":0,"comment_status":"open","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\/8049"}],"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=8049"}],"version-history":[{"count":3,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/8049\/revisions"}],"predecessor-version":[{"id":8056,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/8049\/revisions\/8056"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=8049"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=8049"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=8049"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}