Issue Date: 8/15/2016
Issue Time: 9:22 AM
NO FLOOD THREAT IS FORECAST.
Precipitable water values are expected to rebound a bit today as slightly more mid-level moisture rotates into the state from the north/northwest. Even so, low-level moisture will be lacking for the western two-thirds of Colorado, so any gain over yesterday’s moisture values will be minimal. With that said, this afternoon/evening will see a few more showers/thunderstorms develop as compared to yesterday, thanks to a weak, mid-level disturbance. The best coverage of isolated-to-widely scattered storms will be over the higher terrain, mainly over the Central Mountains, Northern Mountains, Front Range, Southeast Mountains, and San Juan Mountains, where orographic effects play a role. Over the adjacent lower elevations, a few isolated showers/thunderstorms are expected over/near the preferred terrain of the Cheyenne Ridge and Palmer Ridge. Inverted-V atmospheric profiles suggest that the main threats from any storms will be gusty winds and lightning, with only brief periods of light-to-moderate rainfall.
Further to the east over the far Northeast/Southeast Plains and far Palmer Ridge, slightly better low-level moisture can be found. Dewpoints in the 40s will help any isolated storms tap into slightly more efficient rainfall processes, resulting in moderate rainfall. Brief periods of locally heavy rain cannot be ruled out, but no flash flooding issues are expected. For more information regarding rain rates and timing, please see the zone-specific forecast discussions below.
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, jump below the map.
Zone-Specific Forecasts
Urban Corridor, Northeast Plains, Palmer Ridge, Southeast Plains and Raton Ridge:
Mostly sunny skies and temperatures similar to yesterday is the main weather story today. Isolated showers/thunderstorms are expected this afternoon and evening, producing gusty winds, lightning, and mainly light rainfall. A few stronger storms tapping into better surface moisture over the far eastern plains/Palmer Ridge will produce brief periods of locally heavy rain. Maximum rain rates are as follows:
Urban Corridor: 0.3-0.6 inches/hour
Palmer Ridge: 0.4-0.8 inches/hour
Northeast Plains and Southeast Plains: 0.8-1.2 inches
Raton Ridge: 0.2-0.4 inches/hour
Timing: 1 PM – 9 PM, with a few isolated showers/storms lingering until just after midnight
Front Range, Southeast Mountains, Northern Mountains, Northwest Slope, San Juan Mountains, Southwest Slope, San Luis Valley, Central Mountains, and Grand Valley:
A slight uptick in high-based showers/thunderstorms is expected this afternoon/evening as compared to yesterday. Most will remain anchored to the higher terrain, but a couple with move with the steering flow over adjacent lower terrain. With surface moisture lacking, any activity will struggle to maintain itself and will be short-lived. Maximum rain rates are as follows:
Northern Mountains, Northwest Slope, Central Mountains, Southwest Slope, and Grand Valley: 0.15-0.3 inches/hour
San Juan Mountains: 0.4-0.6 inches/hour
San Luis Valley: 0.2-0.4 inches/hour
Front Range and Southeast Mountains: 0.3-0.5 inches/hour
Timing: 11 AM – 10 PM, with one or two lingering showers into the early morning hours
