FTB 06-26-2017: More Isolated Heavy Rainfall Likely, Over Same Areas

Issue Date: Monday, June 26th, 2017
Issue Time: 10:10AM MDT

LOW flood threat for parts of Palmer Ridge (including Waldo Canyon burn scar), Southeast Mountains, and Raton Ridge

Although aloft, the weather pattern of the last 48 hours has hardly changed, the details of the lower levels will be important today. The water vapor image, below, continues to show a seasonably strong high-pressure ridge over the Great Basin. This is causing very warm and dry weather west of the Continental Divide. East of the Continental Divide, a different headline is in store today: very moist low level air. For example, at Colorado Springs, the morning dew point temperature was at 59F – a very high reading especially above 6,000 feet. More of the same is true farther south and east, where yesterday’s rainfall is evaporating and will continue to do so as the strong June sun heats the surface. Isolated to scattered thunderstorms will once again be likely today across the higher elevations and foothills of southeast Colorado. While rainfall rates will be right in the neighborhood of flood-intensity levels, a complicating factor today is antecedent rainfall. Parts of southeast Colorado saw over 0.75 inches of rainfall yesterday, causing areas with saturated soil. Today’s precipitation probability map looks almost identical to yesterday’s observed rainfall map (see Storm Total Precipitation summary). Thus, a Low flood threat is posted for parts of southeast Colorado for isolated flash flooding, debris slides and mud flows.

Today’s Flood Threat Map

For more information on today’s flood threat, see the map below (hover over threat areas for more details). For Zone-Specific forecasts, scroll below the map.

Flood Threat Legend

Zone-Specific Forecasts:

Southeast Plains, Palmer Ridge, Southeast Mountains, Raton Ridge, San Luis Valley, San Juan Mountains:

Sunny early then partly cloudy with isolated to scattered showers and thunderstorms developing by noon. Max 30-minute rainfall up to 0.8 inches and 1-hour rainfall up to 1.3 inches except up to 2.1 inches far southeast. Antecedent wet soils will increase the runoff threat today, thus a Low flood threat has been posted for isolated flash flooding, mud flows and debris slides. The Waldo Canyon burn scar should be monitored closely.

Primetime: 1PM to 11PM

Northeast Plains, Urban Corridor, Front Range:

Sunny early then partly cloudy with isolated showers and thunderstorms possible after noon. The chance of thunderstorms is slim today but if one manages to form, max 30-minute rainfall up to 0.8 inches and 1-hour rainfall up to 1.3 inches is possible. No flood threat is issued today due to low storm probabilities, but if a storm forms, isolated flash flooding will be possible.

Primetime: 2PM to 9PM

Grand Valley, Northwest Slope, Northern Mountains, Central Mountains, Southwest Slope:

Mostly sunny to partly cloudy and continued very warm today. An isolated shower or weak thunderstorm will be possible especially over southern areas. Max 1-hour rainfall up to 0.5 inches. Gusty winds and dry lightning will be more of a threat than rainfall.

Primetime: 12PM to 7PM