{"id":18576,"date":"2022-07-21T14:21:08","date_gmt":"2022-07-21T20:21:08","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=18576"},"modified":"2022-07-25T08:47:35","modified_gmt":"2022-07-25T14:47:35","slug":"fto-07-21-2022-heavy-rainfall-threat-increases-this-weekend-into-next-week-high-threat-issued","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=18576","title":{"rendered":"FTO 07-21-2022: Heavy Rainfall Threat Increases This Weekend Into Next Week; High Threat Issued"},"content":{"rendered":"<p>Issue Date: Thursday,&nbsp;July 21st, 2022<br>\nIssue Time: 2:20PM MDT<br>\nValid Dates:&nbsp;7\/22 &ndash; 8\/5<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-18577\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721-300x39.png\" alt=\"\" width=\"880\" height=\"115\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721-300x39.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721-1024x134.png 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721-768x101.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721-1536x201.png 1536w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721-2048x268.png 2048w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/a><\/p>\n<p>Before we get going with today&rsquo;s FTO, here&rsquo;s a quick look at the estimated number of precipitation days across the state since May 1<sup>st<\/sup>. For reference, it has been 81 days or slightly over halfway through the FTB forecast season. It has been very active along the Front Range and Central Mountains, especially 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>. The Grand Valley and Northwest Slope have also been more active than last year, but more limited precipitation days were noted over the elevated ridges and eastern plains. Overall, it has been a long and active <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> season for the higher terrains, and it sure isn&rsquo;t going to stop for this next FTO period. This is right on time with the peak in climatological <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> for the year.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/SC-ACIS2_rainy_days.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-18578\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/SC-ACIS2_rainy_days-300x280.png\" alt=\"\" width=\"650\" height=\"607\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/SC-ACIS2_rainy_days-300x280.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/SC-ACIS2_rainy_days-768x717.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/SC-ACIS2_rainy_days.png 1020w\" sizes=\"(max-width: 650px) 100vw, 650px\"\/><\/a><\/p>\n<p>Looking at the water vapor imagery below, the High is currently over Arizona with an incoming Low off the west coast. As the Low and subsequent shortwaves move east over the next few days (Event #1), they will start to break down the High before a ridge rebuilds over the Pacific (Event #2). A second High should then develop to our southeast, which will help pull a subtropical moisture plume northward on its west side. As this moisture meets disturbances moving through the northwesterly flow, a very active rainfall pattern is anticipated. Finally, by the end of next week, the High should begin to reestablish itself over the Four Corners region. This should keep rainfall in the forecast for the foreseeable future.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/wv_20220721.png\"><img loading=\"lazy\" class=\"alignnone wp-image-18579\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/wv_20220721-300x161.png\" alt=\"\" width=\"880\" height=\"472\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/wv_20220721-300x161.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/wv_20220721-1024x550.png 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/wv_20220721-768x412.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/wv_20220721-170x90.png 170w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/wv_20220721.png 1416w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/a><\/p>\n<p>As far as the flood threat, after tomorrow, it becomes quite elevated with <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> at or above the long-term average through Tuesday (west) and Thursday (east). A High flood threat has been issued for Sunday through Tuesday with a peak in rainfall activity (intensity and coverage) anticipated on Sunday. An Elevated threat has then been issued for the back end of Event #2, but it is possible that this could be upgraded in Monday&rsquo;s FTO. At that time, there should be better model consensus about where the moisture plume will set up, but it is likely that the heavy rainfall threat will continue over eastern Colorado. The end of Event #2 should be the most favorable pattern 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> rainfall over the eastern plains.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/PW_20220721.png\"><img loading=\"lazy\" class=\"aligncenter wp-image-18580\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/PW_20220721-300x101.png\" alt=\"\" width=\"880\" height=\"297\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/PW_20220721-300x101.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/PW_20220721-1024x346.png 1024w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/PW_20220721-768x260.png 768w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/PW_20220721-1536x519.png 1536w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/PW_20220721-2048x692.png 2048w\" sizes=\"(max-width: 880px) 100vw, 880px\"\/><\/a><\/p>\n<p>One other weather factor for the end of this week will be the continuation of heat on Friday and Saturday. A Heat Advisory has been issued for the Grand Valley tomorrow with a shot at breaking the Grand Junction daily record. A high temperature of 104&deg;F has been forecast with upper 90Fs forecast across the I-25 Corridor. On Saturday, there will be another shot at breaking the Grand Junction daily record as well as the daily records over Alamosa and Pueblo. High temperatures over the eastern plains should reach between 100-105&deg;F, so be sure to hydrate over the next couple of days. A cooldown is anticipated on Sunday with a shot at much cooler temperatures for eastern Colorado on Wednesday behind a strong cold front.<\/p>\n<h4><strong>Event #1:<\/strong><strong> Friday &ndash; <\/strong><strong>Sunday<\/strong><strong> (7\/<\/strong><strong>22<\/strong><strong> &ndash; 7\/<\/strong><strong>24<\/strong><strong>)<\/strong><\/h4>\n<p><strong>There is an increasing threat for this event with a <span style=\"color: #ff0000;\">High<\/span> flood threat issued on Sunday as an abundance of moisture and mid-level dynamics combine 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>, heavy rainfall.<\/strong><\/p>\n<p>More garden variety storms are forecast tomorrow with residual moisture over the area. Best chance 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> to <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;widely scattered&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;10-25% areal coverage&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>widely scattered<\/span> storms will again be across the high terrains favoring areas south with some limited activity possible over the far eastern plains. There should be an uptick in moisture and dynamics on Saturday with <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> storms forecast over the mountains. With steering flows increasing across the northern portion of the state, the flood threat should be limited to the burn areas for this area. Over the central and southern high terrains slower steering flows and some <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;training&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Continuous or repeated rainfall over the same region&nbsp;in a relatively short time span. Training thunderstorms can produce very high rainfall totals and cause flash flooding.&lt;\/div&gt;\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]'>training<\/span> storms could produce <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> heavy rainfall with max 1-hour rain rates up to 1.1 inches possible. Sunday is the peak in rainfall intensity and coverage for this event with activity ramping up due to a 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> and westerly steering flows spilling storms into the adjacent eastern plains. Max 1-hour rain rates up to 1.5 inches (west) and 2.25 inches (east) will be possible along with a couple stronger thunderstorms. A HIGH flood threat has been issued for this day as a Moderate threat or higher will likely be issued in the daily FTB.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e1.snap_.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-18644\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e1.snap_.png\" alt=\"\" width=\"986\" height=\"669\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e1.snap_.png 986w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e1.snap_-300x204.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e1.snap_-768x521.png 768w\" sizes=\"(max-width: 986px) 100vw, 986px\"\/><\/a><\/p>\n<h4><strong>Event #2: <\/strong><strong>Monday<\/strong><strong> &ndash; <\/strong><strong>Thursday<\/strong><strong> (7\/<\/strong><strong>25<\/strong><strong> &ndash; 7\/2<\/strong><strong>8<\/strong><strong>)<\/strong><\/h4>\n<p><strong><span style=\"color: #ff0000;\">High<\/span> flood threat as moisture streams in from the south with embedded disturbances in the mid-levels.<\/strong><\/p>\n<p>Heavy rainfall chances continue at the beginning of next week starting out over the southern high terrains. Best chance for heavy rainfall on Monday will be over southwest Colorado, but ongoing rainfall and cloud cover may help to limit the flood threat over the same area on Tuesday. Storm activity looks to increase over eastern Colorado on Wednesday and Thursday with some heavy rainfall forecast for the elevated ridges and Southeast Plains. Hopefully a storm can dip into the Northeast Plains off the Cheyenne Ridge during this period, with this most likely to occur on Wednesday.<\/p>\n<p><a href=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e2.snap_.png\"><img loading=\"lazy\" class=\"alignnone size-full wp-image-18645\" src=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e2.snap_.png\" alt=\"\" width=\"986\" height=\"670\" srcset=\"https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e2.snap_.png 986w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e2.snap_-300x204.png 300w, https:\/\/archive-coftb.dewberryanalytics.com\/wp-content\/uploads\/2022\/07\/FTO_20220721_e2.snap_-768x522.png 768w\" sizes=\"(max-width: 986px) 100vw, 986px\"\/><\/a><\/p>\n<h4><strong>Event #3: <\/strong><strong>Friday<\/strong><strong> &ndash; <\/strong><strong>Sunday<\/strong><strong> (7\/2<\/strong><strong>9<\/strong><strong> &ndash; 7\/<\/strong><strong>31<\/strong><strong>)<\/strong><\/h4>\n<p><strong><span style=\"color: #0000ff;\">No Apparent<\/span> flood threat as High sets back up over the Four Corners region.<\/strong><\/p>\n<p>A lot of changes are anticipated for Event #3, since it is over a week out before it begins. It looks like the center of the High will set back up over the Four Corners region, which could help produce a rainfall pattern similar to this week. Of course, minor details in the location of the High can be favorable or unfavorable regarding moisture over the state. Likely this will be a mountain rainfall event with minimal spillover into the adjacent eastern plains. Check back in on Monday when the FTO will be updated again.<\/p>","protected":false},"excerpt":{"rendered":"<p>Issue Date: Thursday,&nbsp;July 21st, 2022 Issue Time: 2:20PM MDT Valid Dates:&nbsp;7\/22 &ndash; 8\/5 Before we get going with today&rsquo;s FTO, here&rsquo;s a quick look at the estimated number of precipitation days across the state since May 1st. For reference, it has been 81 days or slightly over halfway through the FTB forecast season. It has [&hellip;]<\/p>","protected":false},"author":8,"featured_media":0,"comment_status":"closed","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\/18576"}],"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=18576"}],"version-history":[{"count":3,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/18576\/revisions"}],"predecessor-version":[{"id":18646,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/18576\/revisions\/18646"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=18576"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=18576"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=18576"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}