{"id":3621,"date":"2016-08-29T10:14:36","date_gmt":"2016-08-29T16:14:36","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=3621"},"modified":"2016-08-30T08:50:26","modified_gmt":"2016-08-30T14:50:26","slug":"ftb-08-29-2016-upper-level-low-will-lift-slowly-across-colorado","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=3621","title":{"rendered":"FTB 08-29-2016: Upper-Level Low Will Lift Slowly Across Colorado"},"content":{"rendered":"<p>Issue Date: 8\/29\/2016<br>\nIssue Time: 10:09 AM<\/p>\n<p><em>A MODERATE FLOOD THREAT IS FORECAST FOR PORTIONS OF THE URBAN CORRIDOR, FRONT RANGE, PALMER RIDGE, SOUTHEAST PLAINS, SOUTHEAST MOUNTAINS, AND RATON RIDGE.<\/em><\/p>\n<p><em>A LOW FLOOD THREAT IS FORECAST FOR SURROUNDING AREAS AND PORTIONS OF THE NORTHEAST PLAINS, CENTRAL MOUNTAINS, SAN JUAN MOUNTAINS, AND SOUTHWEST SLOPE.<\/em><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2016\/08\/WV_20160829.png\"><br><\/a><\/p>\n<p>The upper-level low (shown in the water vapor image below) that was discussed in yesterday&rsquo;s forecast is not in a hurry to move, with its circulation center located across northwestern NM\/southwestern CO. The low will lift slowly towards the northeast through this forecast period, providing favorable dynamics for the development of <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> showers\/thunderstorms along\/east 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>. The best coverage of storms will be over\/near the higher terrain south of I-70, and along the preferred terrain of the Palmer Ridge and Raton Ridge. Instability values are fairly low and <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;wind 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\"}]'>wind shear<\/span> is weak, but favorable dynamics aloft will overcome these limiting factors to produce a few stronger thunderstorms capable of heavy rainfall. Exacerbating any flooding concerns are saturated soils from previous days&rsquo; rainfall, and this is accounted for in the moderate flood threat area. Urban areas and burn scars, such as the Waldo Canyon and Hayden Pass fire burn scars, will need to be monitored closely.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2016\/08\/WV_20160829.png\"><img loading=\"lazy\" class=\"  wp-image-3622 aligncenter\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2016\/08\/WV_20160829.png\" alt=\"WV_20160829\" width=\"540\" height=\"406\"\/><\/a><\/p>\n<p>To the west, daytime heating and orographic effects will be relied upon to produce <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> activity, as the best dynamics will be situated to the east. Cloud cover will be a limiting factor on the amount and intensity of any showers\/thunderstorms that develop, due to daytime heating being of primary importance. In general, expect <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> coverage for northern regions, with more <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> coverage across central and southern regions. For more information regarding timing and rain rates, please see the zone-specific forecast discussions below.<\/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 (hover over threat areas for more details). For Zone-Specific forecasts, jump below the map.<br><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2016\/08\/FTB_20160830.png\"><img loading=\"lazy\" class=\"aligncenter  wp-image-3630\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2016\/08\/FTB_20160830.png\" alt=\"FTB_20160830\" width=\"882\" height=\"503\"\/><\/a><\/p>\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<h3><\/h3>\n<h3><strong>Zone-Specific Forecasts<\/strong><\/h3>\n<h4><strong>Front Range, Southeast Mountains, Urban Corridor, Northeast Plains, Palmer Ridge, Southeast Plains and Raton Ridge:<\/strong><\/h4>\n<p><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>-to-<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> showers and thunderstorms are expected along\/near the higher terrain south of I-70, and along the preferred terrain of the Palmer Ridge and Raton Ridge. Elsewhere, more <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;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> coverage is expected. Heavy rainfall is expected within a few stronger thunderstorms, 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> concerns are exacerbated due to previous days&rsquo; rainfall (especially last night&rsquo;s heavy rain). Maximum rain rates are as follows:<\/p>\n<p>Front Range and Southeast Mountains: 1.0-1.5 inches\/hour<br>\nUrban Corridor: 1.2-1.6 inches\/hour<br>\nSoutheast Plains and Northeast Plains: 2.0-2.5 inches\/hour<br>\nPalmer Ridge: 1.5-2.0 inches\/hour<\/p>\n<p>Timing: 11 AM &ndash; Midnight, with a few showers\/thunderstorms lingering into the morning hours<\/p>\n<h4><strong>Northern Mountains, Northwest Slope, San Juan Mountains, Southwest Slope, San Luis Valley, Central Mountains, and Grand Valley:<\/strong><\/h4>\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;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> showers\/thunderstorms expected, with the best coverage across the Central Mountains, Southwest Slope, and San Juan Mountains. Instability will be fairly meager, as will <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;wind 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\"}]'>wind shear<\/span>, so storm organization\/maintenance will be a limiting factor. Most activity will be garden variety, with only a couple <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> thunderstorms capable of brief heavy rainfall. Maximum rain rates are as follows:<\/p>\n<p>Central Mountains, Southwest Slope, and San Juan Mountains: 0.8-1.1 inches\/hour<br>\nGrand Valley: 0.4-0.6 inches\/hour<br>\nSan Luis Valley: 0.5-0.8 inches\/hour<br>\nNorthwest Slope and Northern Mountains: 0.2-0.5 inches\/hour<\/p>\n<p>Timing: 11 AM &ndash; Midnight<\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: 8\/29\/2016 Issue Time: 10:09 AM A MODERATE FLOOD THREAT IS FORECAST FOR PORTIONS OF THE URBAN CORRIDOR, FRONT RANGE, PALMER RIDGE, SOUTHEAST PLAINS, SOUTHEAST MOUNTAINS, AND RATON RIDGE. A LOW FLOOD THREAT IS FORECAST FOR SURROUNDING AREAS AND PORTIONS OF THE NORTHEAST PLAINS, CENTRAL MOUNTAINS, SAN JUAN MOUNTAINS, AND SOUTHWEST SLOPE. The upper-level [&hellip;]<\/p>","protected":false},"author":1,"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\/3621"}],"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\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3621"}],"version-history":[{"count":2,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/3621\/revisions"}],"predecessor-version":[{"id":3637,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/3621\/revisions\/3637"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3621"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3621"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3621"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}