{"id":14552,"date":"2021-06-24T09:42:05","date_gmt":"2021-06-24T15:42:05","guid":{"rendered":"https:\/\/www.coloradofloodthreat.com\/?p=14552"},"modified":"2021-06-25T07:21:42","modified_gmt":"2021-06-25T13:21:42","slug":"ftb-06-24-2021-widespread-showers-and-thunderstorms","status":"publish","type":"post","link":"https:\/\/archive-coftb.dewberryanalytics.com\/?p=14552","title":{"rendered":"FTB 06-24-2021: Widespread Showers and Thunderstorms"},"content":{"rendered":"

Issue Date: Thursday, June 24th, 2021
\nIssue Time: 9:45AM MDT<\/p>\n

— A LOW<\/strong> flood threat has been posted for parts of the San Juan Mountains, Central Mountains, Grand Valley, Northwest Slope, Northern Mountains, Palmer Ridge and Northeast Plains<\/em>
— Threat will continue later than usual, into the early overnight hours<\/em><\/p>\n

An early dose of monsoonal moisture has finally saturated the lower portion of the atmospheric column, which will allow for much more rainfall coverage today. As shown in the visible satellite image, below, southwesterly flow continues aloft over Colorado, with two notable disturbances seen in the cloud field. PW<\/span> has increased markedly today, going from 0.50 inches to 0.94 inches at Grand Junction today (much above normal for late June), and also up to 0.90 inches at Denver. Once again, almost all weather model guidance continues to underestimate near-surface and total-column moisture. For example, this morning’s RAP analysis underestimated PW<\/span> at Grand Junction and Denver by at least 15%. Furthermore, high-res guidance, notable the HRRR, continues to mix out moisture and underestimate dewpoint temperatures by at least several degrees Fahrenheit every afternoon.<\/p>\n

\"\"<\/a><\/p>\n

For today, there are two areas of concern for heavy rainfall. First, east of the Continental Divide<\/span>, weak upslope flow is expected to develop over northeast Colorado (especially south of I-76), which will support marginally heavy rainfall at the 1-3 hour duration from the climatologically favored Palmer Ridge east-northeastward. A Low flood threat has been posted for this region. Second, west of the Continental Divide<\/span>, a developing disturbance over Utah will trek eastward into Colorado this afternoon, providing synoptic-scale lift. Mainly cloud-free skies this morning will quickly provide moderate instability (CAPE<\/span> up to 800J\/kg with a convective temperature at Grand Junction of only 83F) and support several rounds of showers and thunderstorms mainly over the higher terrain above 6,000 feet. Storms will be capable of 30-60 minute pulses of heavy rainfall up to 1.2 inches\/hour. A Low flood threat has been posted for parts of this region for isolated<\/span> flash flooding<\/span> as well as debris slides and mud flows.<\/p>\n

Lastly, today will provide the summer’s first “test” of the Grizzly Creek and Pine Gulch burn areas. See the Fire Burn Forecast page for forecasts for these and other large burn areas. One reminder on days like today is that our products are outlook-based and thus not meant to serve as real-time warnings. Please stay tuned to local NWS<\/span> offices for any flood-related warning<\/span> products.<\/p>\n

Today’s Flood Threat Map<\/strong><\/h3>\n

For more information on today’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.
\"\"<\/p>\n

Zone-Specific Forecasts:<\/strong><\/h3>\n

Grand Valley, Southwest Slope, Northwest Slope, Central Mountains and Northern Mountains:<\/strong><\/h4>\n

Mostly cloudy with widespread<\/span> showers and thunderstorms increasing in coverage this afternoon, and persisting through the early overnight hours. Max 30-minute rainfall up to 0.8 inches will be possible, with max 1-hour rainfall up to 1.2 inches. A Low flood threat has been posted for parts of the region, for isolated<\/span> flash flooding<\/span>, debris slides and mud flows.<\/p>\n

Primetime: 11AM through midnight<\/p>\n

Palmer Ridge, Northeast Plains and Southeast Plains:<\/strong><\/h4>\n

Partly cloudy with scattered<\/span> to numerous<\/span> showers and thunderstorms developing this afternoon and lasting into the early overnight hours. Max 1-hour rainfall 2.1 inches (east) and 1.4 inches (west) supports a Low flood threat. Large hail and damaging wind will also be possible with the strongest cells near the KS\/NE border.<\/p>\n

Primetime: 2PM through 10PM (west) and 2AM (east)<\/p>\n

Front Range, Urban Corridor, Raton Ridge, Southeast Mountains, San Juan Mountains and San Luis Valley:<\/strong><\/h4>\n

Partly cloudy with scattered<\/span> showers and thunderstorms this afternoon and early evening. Max 1-hour rainfall up to 0.9 inches (east of Continental Divide<\/span>) and 0.6 inches (west). Flooding is NOT expected today although nuisance street ponding will be possible in urban areas.<\/p>\n

Primetime: 1PM through 10PM<\/p>","protected":false},"excerpt":{"rendered":"

Issue Date: Thursday, June 24th, 2021 Issue Time: 9:45AM MDT — A LOW flood threat has been posted for parts of the San Juan Mountains, Central Mountains, Grand Valley, Northwest Slope, Northern Mountains, Palmer Ridge and Northeast Plains — Threat will continue later than usual, into the early overnight hours An early dose of monsoonal moisture […]<\/p>","protected":false},"author":4,"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\/14552"}],"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=14552"}],"version-history":[{"count":4,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/14552\/revisions"}],"predecessor-version":[{"id":14569,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=\/wp\/v2\/posts\/14552\/revisions\/14569"}],"wp:attachment":[{"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=14552"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=14552"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/archive-coftb.dewberryanalytics.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=14552"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}