{"id":14130,"date":"2021-05-31T09:34:09","date_gmt":"2021-05-31T15:34:09","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=14130"},"modified":"2021-05-31T09:34:09","modified_gmt":"2021-05-31T15:34:09","slug":"ftb-05-31-2021-cool-wet-memorial-day-for-most-of-colorado","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=14130","title":{"rendered":"FTB 05-31-2021: Cool &#038; Wet Memorial Day for Most of Colorado"},"content":{"rendered":"<p>Issue Date: Monday, May 31st, 2021<br>\nIssue Time: 9:30AM MDT<\/p>\n<p><em>&mdash; Flooding is&nbsp;<\/em><strong><em>NOT&nbsp;<\/em><\/strong><em>expected today<\/em><\/p>\n<p>Unsettled and cool weather will continue for most this Memorial Day. Currently, there is ample cloud cover over eastern Colorado and the mountains along with fog, rain showers and snow at the highest elevations. It&rsquo;s sunny over the western half of Colorado, especially north where dry northwesterly flow has started to decrease the available moisture in the mid and upper levels of the atmosphere. This split flow pattern, the intrusion of dry air and general subsidence behind 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> is forecast to continue throughout the day over the northern portion of the state. This will drop off the chances for rainfall north of I-70, although some weak showers maybe possible over the mountains (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>) with residual moisture.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-14131\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/wv_20210531.png\" alt=\"\" width=\"600\" height=\"414\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/wv_20210531.png 1168w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/wv_20210531-300x207.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/wv_20210531-768x530.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/05\/wv_20210531-1024x707.png 1024w\" sizes=\"(max-width: 600px) 100vw, 600px\"\/><\/p>\n<p>Further south, 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 the southwest, will continue to help re-enforce the moisture across south, central Colorado seen above&nbsp;(blue\/white shades). As the upslope flow kicks in this afternoon with mid-level energy moving through across the state, <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 are forecast to develop across the Central, Southeast East, San Juan and southern Front Range Mountains (snow above ~11K feet). With cooler temperatures east, more stratiform rainfall with embedded, moderate <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;convection&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Refers to vertical atmospheric motion driven by buoyancy, i.e., warm air is less dense than cool air, and therefore rises. One of the primary drivers of thunderstorm development, especially during monsoon season.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>convection<\/span> is likely. Some spill over into the adjacent, eastern plains and ridges is possible late this afternoon\/evening with the southeast moving storms. Over the western high terrains (south), rainfall totals should slightly increase from yesterday due to a slight increase in <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> (0.56 inches at Grand Junction) and more moist <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>. Stronger storms that develop this afternoon will likely produce lightning, wind gusts and moderate rainfall with slow steering flow. With the southeast movement of storms, the San Luis Valley should also record measurable rainfall for the second day in a row. Rain rates are gradual enough today, thanks to limited instability, that flooding is NOT forecast.<\/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><img loading=\"lazy\" class=\"wp-image-13436 aligncenter\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/04\/FTB_No_Flood_Threat_2021.png\" alt=\"\" width=\"717\" height=\"538\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/04\/FTB_No_Flood_Threat_2021.png 1292w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/04\/FTB_No_Flood_Threat_2021-300x225.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/04\/FTB_No_Flood_Threat_2021-768x576.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2021\/04\/FTB_No_Flood_Threat_2021-1024x768.png 1024w\" sizes=\"(max-width: 717px) 100vw, 717px\"\/><\/p>\n<h3><strong>Zone-Specific Forecasts:<\/strong><\/h3>\n<h4><strong>Southeast Plains, Raton Ridge, Palmer Ridge, &amp; Southeast Mountains: <\/strong><\/h4>\n<p>Gradual rainfall due to cooler temperatures should accompany the <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> storms that develop over the mountains this afternoon. Max 1-hour rain rates up to 0.60 inches over the mountains 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> 24-hour totals up to 1 inch are possible. Rain should start to cross over to snow again at the higher elevations by this evening ending the flood threat for the higher elevation burn areas. Southeast movement of storms will spill rainfall into the adjacent plains and ridges late this afternoon. Max 1-hour rain rates up to 0.25 inches will be possible. Flooding is NOT forecast today.<\/p>\n<p>A <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;flash flood&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 Flood<\/span> <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Watch&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 weather watch is issued when conditions are favorable for a specific weather event to occur&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>Watch<\/span> has been re-issued by <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;NWS&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;National Weather Service&lt;\/div&gt;\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>NWS<\/span> Pueblo for the burn areas over the Southeast Mountains. Head on over to the FBF for our burn area forecast for today.<\/p>\n<p>Primetime: 1PM to 10PM<\/p>\n<h4><strong>Central Mountains, San Juan Mountains, Southwest Slope &amp; San Luis Valley:<\/strong><\/h4>\n<p><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> storms will develop over the high terrains this afternoon with decent moisture, mid-level lift and upslope flow. I&rsquo;m sure everyone is looking forward to the <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>, measurable rainfall for the mountains. A couple stronger storms may be possible south (initially) with the main threats being <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, lightning and small hail. Moderate rainfall with 1-hour rain rates up to 0.60 inches will be possible. <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> totals over the eastern San Juan Mountains could reach around 0.75 inches by late this evening. As storms move southeast with the steering flow, showers will likely spill into the San Luis Valley. Totals up to 0.75 inches will be possible by morning around the southern tier&nbsp;of the valley. Flooding is NOT forecast.<\/p>\n<p>Primetime: 11AM to 10PM<\/p>\n<h4><strong>Front Range, Urban Corridor, Northeast Plains, Northwest Slope, Northern Mountains &amp; Grand Valley:<\/strong><\/h4>\n<p>Dry air and subsidence will limit the chances for rainfall this afternoon over these regions. A couple showers&nbsp;will likely still develop over the mountains with the residual moisture, but 1 hour rain rates should remain around 0.15 inches. Cloudy conditions will persist over the Urban Corridor this morning along with weak showers as well with temperatures remaining below average this afternoon. Over the northwest corner of the state, sunny skies with temperatures slightly above normal are forecast.<\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Monday, May 31st, 2021 Issue Time: 9:30AM MDT &mdash; Flooding is&nbsp;NOT&nbsp;expected today Unsettled and cool weather will continue for most this Memorial Day. Currently, there is ample cloud cover over eastern Colorado and the mountains along with fog, rain showers and snow at the highest elevations. It&rsquo;s sunny over the western half of [&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\/14130"}],"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=14130"}],"version-history":[{"count":2,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/14130\/revisions"}],"predecessor-version":[{"id":14133,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/14130\/revisions\/14133"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=14130"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=14130"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=14130"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}