Issue Date: Tuesday, June 21st, 2016
Issue Time: 10:15AM MDT

— Flooding is NOT expected today

Today’s weather setup features plenty of residual moisture that has been trapped by the inversion. Morning Precipitable Water values range from 0.5 to 1.1 inches across the state. However, the moisture is rather shallow, and air above the boundary layer is noticeably drier. The Rocky Mountain ridge (see water vapor image below) is centered over New Mexico today placing Colorado in an area of subsidence aloft. Furthermore, despite the residual low-level moisture, surface flow will have a westerly component across most of the state. This implies downsloping east of the Continental Divide, which is not conducive for rainfall. Nonetheless, like on Monday, the high terrain will create its own circulation and scattered to isolated thunderstorms are expected across the southern and southeastern mountain regions. A brief heavy downpour is possible, but a flood threat is not warranted today.

Very hot temperatures, the highest of the young summer for many locales, will accompany the ridge circulation. Afternoon highs could exceed 105F along the lowest elevations of the Colorado, South Platte and Arkansas River valleys. An elevated wildfire threat will exist across the higher terrain, especially in regions with thunderstorm activity (because of dry lightning).

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: Monday, June 20th, 2016
Issue Time: 10:45AM MDT

— MODERATE flood threat for parts of the Front Range, Urban Corridor, Palmer Ridge, Southeast Plains and Southeast Mountains
— LOW flood threat for parts of Northeast Plains, Central Mountains and Raton Ridge

Today’s visible satellite imagery, below, shows a rather small-scale but nonetheless impressive plume of low-level moisture being transported in from Nebraska. Despite the presence of a stout upper-level ridge, centered over southern Colorado, it is often said the higher terrain such as the 14ers that our state sports can generate its own circulation. Today will be an excellent example of this. As the plume of moisture, with Precipitable Water values as high as 1.3 inches makes it upslope over the Palmer Ridge, strong elevated heating will generate a strong cyclonic circulation in the lowest ~8,000 feet of the atmosphere. This will set the stage for plenty of instability for scattered to widespread thunderstorms. Heavy rainfall will be likely today over the higher elevations of the southern Front Range and western Palmer Ridge. Furthermore, slow wind speeds will favor slow storm motion, while deep easterly flow will contribute to the possibility of training where repeated cells pass over the same area twice. A Moderate flood threat has been issued for the Palmer Ridge, with a Low threat for surrounding areas. Of particular concern will be fire scars, such as the fresh “TA-27” fire scar in El Paso County.

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: Sunday, June 19th, 2016
Issue Time: 9:00AM MDT

— Flooding is NOT expected today
— Elevated wildfire threat for central and western parts of the state

The water vapor image, below, continues to show the infamous ridge centered just south of Colorado this morning. Today could mark the high-point of the ridge’s strength with afternoon 500-mb heights (roughly 8,000 – 14,000 feet above ground level, depending on elevation) forecasted to exceed an impressive 6,000 meters. The net effect of this will be strong mid-level subsidence that will continue to squash precipitation chances statewide. The only other notable feature on the weather map is a weak cool front that is currently moving south and east out of Wyoming. This will provide the only potential for rainfall across the Palmer Ridge to the Northeast Plains. However, rainfall chances and coverage here will be very low. Flooding is not expected today.

Prolonged warm and dry weather in Colorado is often accompanied by an elevated wildfire threat. This afternoon, widespread parts of the state will once again experience relative humidity values less than 20%, and less than 10% in many areas (see map below from the Fire-weather WRF). This will once again support wildfire chances. Fortunately, low wind speed will partially mitigate this threat.

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: Saturday, June 18th, 2016
Issue Time: 8:25AM MDT

— Flooding is NOT expected today

Low-level moisture is in place this morning east of the Continental Divide after yesterday’s cool front passage. Dew point temperatures are in the 45-55F range which is rather high by Colorado standards. However, this morning’s soundings at both Denver and Grand Junction, below, show a strong mid-level inversion being driven by the ridge centered over New Mexico. Mid-level temperatures have warmed up to 8F, and are now about 5F warmer than average. This prevents instability from building up, and strongly limits storm chances. Expect a gradual mixing out of moisture through some puffy clouds, along with hot temperatures statewide. The only slight chance of a shower or weak thunderstorm is in the extreme southeast portion of the state, but flooding is not expected today.

West of the Divide, soils have continued to dry with the lack of meaningful precipitation over the past several weeks. The wildfire threat remains elevated today, but the limiting factor is relatively low wind speeds. Nonetheless, folks should stay tuned to local National Weather Service updates regarding this threat.

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: