Issue Date: Wednesday, May 31st, 2017
Issue Time: 10:40AM MDT

— LOW flood threat for parts of Northeast Plains, Palmer Ridge, Raton Ridge and Southeast Plains

With plenty of morning sunshine, temperatures will continue their steady trend upwards today across Colorado. Moisture also continues to increase, albeit slowly, as weak southeasterly flow brings in moist air from the Southern Plains. Added to the mix is an approaching disturbance from the southwest (see water vapor image below) that will cause upward motion downstream of its vorticity axis. Collectively, expect shower and storm coverage to increase today across southwest and eastern Colorado. Most rainfall will be of the light to moderate variety, and not pose a flood threat. However, two areas are exceptions to this rule. First, along the Raton Ridge, early instability will provide scattered storms that will be capable of heavy rainfall due to slow storm motion (much like Monday). Second, in the Northeast Plains and far eastern Colorado, higher instability and favorable directional and speed shear profiles suggest isolated severe storms. With precipitable water approaching 0.7-0.8 inches this afternoon, isolated heavy rainfall will be possible with these. In addition, large hail is also possible.

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.

Issue Date: Tuesday, May 30th, 2017
Issue Time: 10:50AM MDT

— LOW flood threat for parts of Southeast Mountains, Raton Ridge and Southeast Plains

Another crystal clear start to the day today will allow for strong insolation as we are getting closer to summer’s peak heating. At the upper-levels, as the water vapor image shows below, a large trough continues to be centered across central/eastern North America. As the trough slowly continues to move eastward through the day, Colorado will be increasingly affected by subsidence from the high-pressure ridge to the west. However, its impacts will be felt more so west of the Continental Divide. To the east, elevated heating will cause a weak upslope circulation to develop especially in southeast Colorado. With just enough low-level moisture, scattered showers and thunderstorms will dot the landscape by the afternoon. While the storms won’t be overly impressive, they will be steered by very light winds, less than 25mph. Thus, they will be capable of producing isolated heavy rainfall, much like on Monday. A Low flood threat is posted today for the foothills of southeast Colorado for isolated flash flooding, debris slides and debris 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.

Zone-Specific Forecasts:

Raton Ridge, Southeast Mountains, Southeast Plains, Northeast Plains, Front Range, Urban Corridor, Palmer Ridge:

Mostly clear this morning then partly cloudy with isolated to scattered showers and thunderstorms possible. Highest coverage will be in the foothills and western plains of southeast Colorado. Max 1-hour rainfall up to 0.6 inches except up to 1.1 inch in southern areas. A Low flood threat has been posted for parts of the region. Small hail up to 0.5 inches could accompany the stronger cells.

Primetime: 2PM to 8PM

San Juan Mountains, Southwest Slope, Grand Valley, San Luis Valley, Northwest Slope, Northern Mountains, Central Mountains:

Sunny this morning then becoming partly cloudy with isolated showers and a weak thunderstorm possible mainly in the higher elevations of the San Juans and southern portions of the Central Mountains. Max 1-hour rainfall up to 0.3 inches. Small hail (up to 0.25 inches) could accompany the stronger cells. Flooding is not expected today.

Primetime: 12PM to 7PM

Issue Date: Monday, May 29th, 2017
Issue Time: 9:30AM MDT

— Flooding is NOT expected today

Happy Memorial Day!

This morning’s water vapor image, below, shows a large trough centered over the northern Great Plains providing Colorado with seasonably cool temperatures but limited moisture for thunderstorm activity. Statewide, this morning’s precipitable water values are in the 0.4 – 0.6 inch range, and a continuation of these levels is expected over the next 24 hours. As we head closer into the summer season, strong insolation can create enough instability even with meager moisture. Such will be the case today. With mainly clear skies this morning, temperatures will warm to near seasonal averages, and enough instability will be generated for scattered showers and weak thunderstorms. Coverage will be highest east of the Continental Divide, where the moisture supply is better. Most locations will see light rainfall, but a few heavier downpours will be likely. However, the duration of the downpours will be short enough to limit runoff. Thus, flooding is not expected today.

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.

Zone-Specific Forecasts:

Raton Ridge, Southeast Mountains, Southeast Plains, Northeast Plains, Front Range, Urban Corridor, Palmer Ridge:

Mostly clear this morning then partly cloudy with isolated to scattered showers and thunderstorms possible. Highest coverage will be in the foothills and western plains. Max 1-hour rainfall up to 0.7 inches except up to 1.0 inch in the Southeast Plains. Small hail up to 0.5 inches could accompany the stronger cells. Flooding is not expected today.

Primetime: 1PM to 9PM

San Juan Mountains, Southwest Slope, Grand Valley, San Luis Valley, Northwest Slope, Northern Mountains, Central Mountains:

Sunny this morning then becoming partly cloudy with isolated showers and a weak thunderstorm possible mainly in the higher elevations of the Continental Divide. Max 1-hour rainfall up to 0.3 inches. Small hail (up to 0.25 inches) could accompany the stronger cells. Flooding is not expected today.

Primetime: 12PM to 7PM

Issue Date: Sunday, May 28th, 2017
Issue Time: 9:15AM MDT

— Flooding is NOT expected today

After a busy past few days, visible satellite imagery this morning shows a “severe clear” atmosphere – not a cloud over Colorado. With pressure levels rising in height today, and precipitable values below 0.5 inches statewide, expect large-scale subsidence to keep most everyone dry. One exception will be in the Northeast Plains, where some light showers or a weak storm could pop up this afternoon. The second exception will be over the higher terrain of the Front Range and Central Mountains where the elevated heating could cause a few weak showers (possibly a weak thunderstorm). For everyone else, enjoy this splendid Sunday. Hikers: please remember that a thunderstorm can produce lightning without causing rainfall!

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.

Zone-Specific Forecasts:

Raton Ridge, Southeast Mountains, Southeast Plains, Northeast Plains, Front Range, Urban Corridor, Palmer Ridge:

Mostly clear this morning then partly cloudy with some isolated showers possible in the Northeast Plains and higher elevations. Max 1-hour hour rain rates of 0.2 inches in the lower elevations, and 0.1 inch in the higher elevations. Flooding is not expected today. Hikers: be aware that a thunderstorm can produce lightning without producing rain.

Primetime: 1PM to 6PM

San Juan Mountains, Southwest Slope, Grand Valley, San Luis Valley, Northwest Slope, Northern Mountains, Central Mountains:

Sunny this morning then a few clouds possible this afternoon. An isolated shower or perhaps weak thunderstorm will be possible mainly in the Central Mountains. Little if any precipitation is expected to reach the ground. However, lightning is always possible with thunderstorms so hikers be aware. Flooding is NOT expected today.

Primetime: 12PM to 5PM