Issue Date: 8/18/2015
Issue Time: 8:25 AM
NO FLOOD THREAT IS FORECAST.
The air mass over Colorado has dried out considerably behind a cool front that passed through the state, with precipitable water values diving below 0.7 inches at all four normal reporting stations. From the 6 AM Denver and Grand Junction soundings, precipitable water values are in the 25th percentile for the date. Altogether, the moisture decline outlines the no flood threat forecast.
There will be isolated-to-scattered showers and weak thunderstorms this afternoon and into the overnight hours, mainly along the Continental Divide and east to the CO/KS border. Precipitation is expected to be light, so no flooding concerns will arise from this activity. Rain rates and timing will be outlined in the zone-specific discussions below. West of the Continental Divide, a dry and cool day is expected.
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
Front Range, Northern Mountains, Central Mountains, and Southeast Mountains:
Isolated-to-scattered showers/weak thunderstorms expected this afternoon and into the overnight hours. Rain rates will be low at 0.15-0.30 inches/hour. Otherwise, partly sunny skies and cool temperatures will be the main story.
Timing: 2 PM – 4 AM
Urban Corridor, Northeast Plains, Southeast Plains, Palmer Ridge, and Raton Ridge:
Isolated-to-scattered showers/weak thunderstorms are expected over these regions, as well. Activity will get a later start today as compared to recent days, beginning in the mid-afternoon hours, and continuing into the early morning hours tomorrow. Rain rates will not be impressive, coming in at 0.25-0.5 inches/hour under thunderstorms, 0.05-0.15 inches/hour under stratiform showers. Otherwise, expect a partly sunny and cooler forecast period.
Timing: 3 PM – 6 AM
San Juan Mountains, Grand Valley, San Luis Valley, Northwest Slope, and Southwest Slope:
Cooler and dry, with high temperatures about 8-12 degrees cooler than yesterday across all locations. Windy conditions will bring elevated fire concerns, and a Red Flag Warning has been issued across portions of the Southwest Slope. Stay up-to-date on changing fire weather conditions with your local NWS office.
