{"id":1500,"date":"2015-08-03T14:38:41","date_gmt":"2015-08-03T20:38:41","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=1500"},"modified":"2015-08-03T14:38:41","modified_gmt":"2015-08-03T20:38:41","slug":"fto-08-03-2015-monsoon-moisture-pulses-cool-fronts-active-weather","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=1500","title":{"rendered":"FTO 08-03-2015: Monsoon Moisture Pulses + Cool Fronts = Active Weather"},"content":{"rendered":"<p>Issue Date: 8\/3\/2015<br>\nIssue Time: 2:30PM<br>\nValid Dates: August 4 &ndash; August 18<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/08\/threat_timeline.20150803.png\"><img loading=\"lazy\" class=\"aligncenter  wp-image-1502\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/08\/threat_timeline.20150803.png\" alt=\"threat_timeline.20150803\" width=\"767\" height=\"101\"\/><\/a>Mother Nature is not taking her foot off the gas pedal, at least when it comes to the continued prospects of active weather across Colorado. Two things are particularly noteworthy in this afternoon&rsquo;s snapshot of the atmosphere, shown below in the water vapor image. First, we see two low-pressure disturbances in the Gulf of Alaska. Interestingly, these disturbances are somewhat solitary, in the sense that they are not strongly attached to any significant steering winds. The end result is that their movement will be very slow. Ultimately, both of these features are anticipated to influence our weather over the time period covered by this Flood Threat Outlook.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/08\/watervapor_201508032.png\"><img loading=\"lazy\" class=\"aligncenter  wp-image-1504\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/08\/watervapor_201508032.png\" alt=\"watervapor_20150803\" width=\"629\" height=\"408\"\/><\/a>Second, we continue to see pulses of tropical moisture being fed into the southwest United States. Of course, this is quite typical of late summertime due to the monsoonal circulation. However, from a moisture supply perspective, this <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;monsoon&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 seasonal wind that brings moisture and rain to the region into which it blows; there is also a dry phase to monsoons, but popular usage refers only to the wet phase; these winds occur in many places around the world, and where they occur they are responsible for a majority of that location&rsquo;s annual precipitation&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>monsoon<\/span> has been quite an active one thus far. Below we show how <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>) has fared thus far season in Albuquerque, NM. The reason we chose a site in New Mexico is because it is a good proxy for what is entering Colorado from the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;monsoon&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 seasonal wind that brings moisture and rain to the region into which it blows; there is also a dry phase to monsoons, but popular usage refers only to the wet phase; these winds occur in many places around the world, and where they occur they are responsible for a majority of that location&rsquo;s annual precipitation&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>monsoon<\/span> moisture flow. We also show a comparison with 2014 (a +\/- typical year) and 2012 (a drought year). There are a few things worth noting:<\/p>\n<ul><li>This year Albuquerque surpassed the 1 inch <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> threshold on June 10<sup>th<\/sup>. This is very early, as note how it took until July 1<sup>st<\/sup> in both 2012 and 2014 for that value to be exceeded.<\/li>\n<li>Note that when <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> exceeds 1 inch in Albuquerque, it typically does not stay at that level very long (1-2 days). However, this year there have been 3-5 day stretches where <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> has maintained at 1 inch or greater, with the latest period coming over the past few days.<\/li>\n<\/ul><p>These findings reiterate how incredibly moist this summer has been. Of course, moisture is only a proxy for actual rainfall. But a particularly good proxy in Colorado.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/08\/ABQ_ipw_comparison.png\"><img loading=\"lazy\" class=\"aligncenter  wp-image-1501\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/08\/ABQ_ipw_comparison.png\" alt=\"ABQ_ipw_comparison\" width=\"271\" height=\"295\"\/><\/a><\/p>\n<p>Back to the forecast, over the course of the next 15 days, we see two time periods with heavy rainfall potential. Both of these Events are classified with an Elevated flood threat. Let&rsquo;s look at the details of each Event:<\/p>\n<p><strong>Event #1: Thursday (8\/6) through Saturday (8\/8)<\/strong><\/p>\n<p>An <span style=\"color: #ff6600;\"><strong>Elevated<\/strong><\/span> flood threat, mainly east of the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;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\"}]'>Divide<\/span><\/p>\n<p>The Pacific disturbance will slowly trek from the Gulf of Alaska and impact Colorado by later next week. As this disturbance will likely be coming in from the west\/northwest, it appears that the monsoonal connection may be limited. However, this is somewhat uncertain, especially given the tendency for models to underestimate the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;monsoon&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 seasonal wind that brings moisture and rain to the region into which it blows; there is also a dry phase to monsoons, but popular usage refers only to the wet phase; these winds occur in many places around the world, and where they occur they are responsible for a majority of that location&rsquo;s annual precipitation&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>monsoon<\/span> feed. We anticipate that the Northeast Plains will be under the highest threat for heavy rainfall as a cool front makes its way down the east face of the Rockies, promoting easterly upslope flow. The cool front will have the opportunity to sag all the way southward through the state, which will provide for rainfall chances even in the Southeast Plains. In additional to the rainfall threat, since this disturbance will be accompanied by <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;jet stream&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Relatively strong winds concentrated within a narrow stream in the atmosphere. General weather patterns are related closely to the position, strength and orientation of the jet stream.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>jet stream<\/span> dynamics, hail and strong winds may be possible especially on Thursday 8\/6.<\/p>\n<p><iframe loading=\"lazy\" src=\"https:\/\/a.tiles.mapbox.com\/v4\/sgeiger.n1npfpj2\/attribution,zoompan,zoomwheel,geocoder,share.html?access_token=pk.eyJ1Ijoic2dlaWdlciIsImEiOiJmNjc5a3RBIn0.LbLupVkJsS5dbo9fsgrTDg\" width=\"100%\" height=\"500px\" frameborder=\"0\"><\/iframe><br><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/05\/Legend.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-230\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/05\/Legend.png\" alt=\"Legend\" width=\"94\" height=\"158\"\/><\/a><\/p>\n<p><strong>Event #2: Tuesday (8\/11) through Thursday (8\/13)<\/strong><\/p>\n<p>An <span style=\"color: #ff6600;\"><strong>Elevated<\/strong><\/span> flood threat east of the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;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\"}]'>Divide<\/span><\/p>\n<p>After a several day break from Event #1, the polar <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;jet stream&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Relatively strong winds concentrated within a narrow stream in the atmosphere. General weather patterns are related closely to the position, strength and orientation of the jet stream.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>jet stream<\/span> will remain active as the subtropical high is anticipated to move <em>west<\/em> of Colorado. With the state being in a northwest steering flow, it will be areas east of the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;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\"}]'>Divide<\/span> that will have the greatest heavy rainfall chance. At least one cool front, originating in the northeast Pacific Ocean, may come down the Northeast and Southeast Plains provide several afternoons of thunderstorm activity. In particular, the Palmer Ridge may see the highest rainfall values due to its ability to temporarily slow down frontal passages. As with Event #1, this event should be supported by a moderate to strong <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;jet stream&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Relatively strong winds concentrated within a narrow stream in the atmosphere. General weather patterns are related closely to the position, strength and orientation of the jet stream.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>jet stream<\/span>, which will lead to the threat of gusty winds and hail in addition to the heavy rainfall. However, despite the potential for <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> <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>, the good news is that northwest flow events are typically NOT conducive for major flooding in Colorado. It is also worth noting that there are indications of a fall-like cool front to impact the state towards the end of the forecast period. It is far early to speculate whether this will come to fruition, but certainly a reminder that summer&rsquo;s days are numbered.<\/p>\n<p><iframe loading=\"lazy\" src=\"https:\/\/a.tiles.mapbox.com\/v4\/sgeiger.n311cac7\/attribution,zoompan,zoomwheel,geocoder,share.html?access_token=pk.eyJ1Ijoic2dlaWdlciIsImEiOiJmNjc5a3RBIn0.LbLupVkJsS5dbo9fsgrTDg\" width=\"100%\" height=\"500px\" frameborder=\"0\"><\/iframe><br><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/05\/Legend.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-230\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2015\/05\/Legend.png\" alt=\"Legend\" width=\"94\" height=\"158\"\/><\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: 8\/3\/2015 Issue Time: 2:30PM Valid Dates: August 4 &ndash; August 18 Mother Nature is not taking her foot off the gas pedal, at least when it comes to the continued prospects of active weather across Colorado. Two things are particularly noteworthy in this afternoon&rsquo;s snapshot of the atmosphere, shown below in the water [&hellip;]<\/p>","protected":false},"author":4,"featured_media":0,"comment_status":"open","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\/1500"}],"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\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1500"}],"version-history":[{"count":1,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/1500\/revisions"}],"predecessor-version":[{"id":1505,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/1500\/revisions\/1505"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1500"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1500"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1500"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}