{"id":11575,"date":"2020-05-21T12:27:27","date_gmt":"2020-05-21T18:27:27","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=11575"},"modified":"2020-05-25T11:03:57","modified_gmt":"2020-05-25T17:03:57","slug":"fto-05-21-2020-high-fire-danger-to-start-memorial-weekend-before-storms-return-sunday","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=11575","title":{"rendered":"FTO 05-21-2020: High Fire Danger to Start Memorial Weekend before Storms Return Sunday"},"content":{"rendered":"<p>Issue Date: Thursday,&nbsp;May 21st, 2020<br>\nIssue Time: 12:30PM MDT<br>\nValid Dates:&nbsp;5\/22 &ndash; 6\/5<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-11576\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/05\/FTO-20200521.png\" alt=\"\" width=\"880\" height=\"146\"\/><\/p>\n<p>There will be two events for this FTO, and both will originate from the Low just off the coast of British Columbia\/Washington. This Low is expected to slip southwards into the Great Basin Friday into Saturday. Initially, it will pull in a dry air mass and increase fire danger on Friday and Saturday. However, a cold front is expected to drop through Saturday night, which will help return moisture for <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> storm activity on Sunday into Monday. By late Monday into Tuesday, it should start to dry out with warmer temperatures forecast for mid-week when the ridge axis shifts east.<\/p>\n<p>Long-range models are hinting at the mid-level energy from Event #1 hanging out somewhere over Texas and getting cut off from the main flow (Event #2). This would pull higher <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 northward on its east and north side (counter-clockwise motion) and return the chances for afternoon rain towards the end of the week. With a northwest flow likely returning aloft over the weekend, it may push another cold front south, which could interact with these higher <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. Thus, the Elevated Threat for flooding during Event #2.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-11577 size-full\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/05\/wv-20200521.png\" alt=\"\" width=\"776\" height=\"472\"\/><\/p>\n<p>As anticipated and focused on in the last FTO, one of the main weather stories for this FTO is the <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;critical fire weather&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;weather conditions especially conducive to the formation of wildfires; typically strong winds, low relative humidity, and atmospheric instability&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>critical fire weather<\/span> forecast over Memorial Day weekend. The new drought map was released today which has increased the D3 area over the southern border, so it is dry! <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 Grand Junction (and south) are in the 10<sup>th<\/sup> percentile for this time of year. Another SW to NE oriented <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;jet streak&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;The region of a jet stream with the strongest winds.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>jet streak<\/span> will be over Colorado Friday\/Saturday, which will increase surface winds into the 10-25 mph range with gusts 10 to 20 mph higher. Be sure to tune into your local <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> office for the latest and use caution with open flames while camping. There are already many counties with fire restrictions in place, so here is a map with those <u><span style=\"color: #0000ff;\"><a style=\"color: #0000ff;\" href=\"http:\/\/www.coemergency.com\/p\/fire-bans-danger.html\"><strong>current restrictions<\/strong><\/a><\/span>.<\/u> A Fire Weather <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> is already &nbsp;in place for most of western and southern Colorado for tomorrow afternoon.<\/p>\n<p>With that said, not much rainfall anticipated except for some <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>, high-based storms over the mountains on Friday and Saturday. Moisture increases behind the aforementioned cold front, but this looks mostly to be 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>. Storms should be mostly stratiform in nature Sunday into Monday, but if more convective storms can form on Sunday afternoon, we&rsquo;ll have to <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> the Spring Creek and Decker burn areas. At the tail end of the Denver <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> plume is the increase in subtropical moisture mentioned&nbsp;for Event #2.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-11578\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/05\/pw20200521.png\" alt=\"\" width=\"880\" height=\"303\"\/><\/p>\n<p>No change to the streamflow forecasts from the last couple of FTOs, but I just wanted to mention that the <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;SWE&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;strong&amp;gt;S&amp;lt;\/strong&amp;gt;now &amp;lt;strong&amp;gt;W&amp;lt;\/strong&amp;gt;ater &amp;lt;strong&amp;gt;E&amp;lt;\/strong&amp;gt;quivalent, the liquid water content of snowpack&amp;lt;\/p&amp;gt;\n&amp;lt;!-- \/wp:paragraph --&amp;gt;&lt;\/div&gt;\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>SWE<\/span> from SNOTEL sites over the Upper Rio Grande Basin are showing complete melt out after this last hot stretch of temperatures. The San Miguel, Dolores, Animas and San Juan River Basins look like they will also melt out by early next week. This is very early (relative to climatology), which is typically in mid to end of June. Unless there is a major pattern shift over the next couple of months, we&rsquo;ll be dealing with very high fire danger this summer due to the dry spring\/end of winter.<\/p>\n<h3><strong>Event #1: <\/strong><strong>Sunday<\/strong><strong> &ndash; <\/strong><strong>Mon<\/strong><strong>day (5\/<\/strong><strong>24<\/strong><strong>-5\/<\/strong><strong>25<\/strong><strong>)<\/strong><\/h3>\n<p><strong><span style=\"color: #0000ff;\">No Apparent Threat<\/span>&nbsp;<\/strong>as moisture return from a cold front and surface low return <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> shower activity to the state.<\/p>\n<p>Storm activity is expected to increase on Sunday with the main vorticity max moving into the state and a surface low forming over the Northeast Plains. Overall, there will be cooler temperatures with storms kicking off over the mountains by noon and activity spreading into the adjacent plains by mid-afternoon. 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>, so not expecting any severe weather at this time. A couple stronger storms could produce high enough rain rates (0.50 inches per hour) that would cause issues for recent burn areas over the Southeast Mountains, so we will be watching this closely. Storms may linger over the Southeast Mountains and immediate adjacent plains overnight, which would help increase totals. But that would be very welcomed with the lack of rainfall the last couple of months. Due to the anticipated stratiform nature of the storms, not thinking flooding is going to be an issue at this time, especially because it begins to dry out on Monday. Thus, there is No Apparent threat.<\/p>\n<p><img loading=\"lazy\" class=\"aligncenter wp-image-11622\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2020\/05\/FTO_20200521_e1.png\" alt=\"\" width=\"880\" height=\"596\"\/><\/p>\n<h3><strong>Event #2: <\/strong><strong>Thursday &ndash; Sunday<\/strong><strong> (<\/strong><strong>5\/28-<\/strong><strong>5\/<\/strong><strong>31<\/strong><strong>)<\/strong><\/h3>\n<p><strong><span style=\"color: #ff6600;\">Elevated Threat<\/span>&nbsp;<\/strong>as a &ldquo;cut off low&rdquo; pattern pulls subtropical moisture northward.<\/p>\n<p>If the vorticity lobe is able to be cut off from the main flow as it passes through the state to start next week, it could create a nice surge of subtropical moisture northward into the state on its east and north side. Of course, this all depends on the strength, persistence and placement of that low. At this time, it&rsquo;s a little too far out to know the details, but we should see an uptick in storms by the end of next week. Northwest flow will likely return to the state as the pattern begins to break up next weekend, which will likely drop a cold front southward. There will be an Elevated flood threat during that time if high moisture is intact over the state. Due to low confidence in the placement, strength and persistence of the low this far out, a map has not been drawn. Please tune back into the FTO on Monday as details will likely have evolved.<\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Thursday,&nbsp;May 21st, 2020 Issue Time: 12:30PM MDT Valid Dates:&nbsp;5\/22 &ndash; 6\/5 There will be two events for this FTO, and both will originate from the Low just off the coast of British Columbia\/Washington. This Low is expected to slip southwards into the Great Basin Friday into Saturday. Initially, it will pull in a [&hellip;]<\/p>","protected":false},"author":8,"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\/11575"}],"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=11575"}],"version-history":[{"count":2,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/11575\/revisions"}],"predecessor-version":[{"id":11623,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/11575\/revisions\/11623"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=11575"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=11575"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=11575"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}