Time: 938 PM Sun July 21, 2019 Forecaster: Alan Smith

Internal Message Status
Flash Flood Prediction Program

MESSAGES HAVE BEEN EXTENDED FOR THE ENTIRE DISTRICT UNTIL 11:59PM
-Message 1's have been extended for the entire District until 11:59pm. A Message 3 Flash Flood Warning remains in effect for Douglas County until 11:45pm.
-An outflow boundary has triggered a line of slow-moving/stationary thunderstorms across western portions of the District near the foothills, and additional isolated thunderstorms have developed over eastern portions of the District as well.
-Thunderstorms this evening are very efficient rainfall producers, and the potential for slow-moving and training thunderstorm cells will continue to result in a threat for heavy rainfall, excessive runoff, street flooding and small stream flooding over the next couple of hours.
STORM RAINFALL POTENTIAL AND DURATION: Thunderstorms will be capable of producing rainfall amounts of 0.5-1.5" in 10-30 minutes.

WORST CASE SCENARIO: Training of thunderstorm cells could result in heavy rainfall of up to 3.5" in 90-120 minutes.

County Message Valid Times Prime Time
the City of Aurora 1 Current TO 1159 PM Current TO 1130 PM
Arapahoe County 1 Current TO 1159 PM Current TO 1130 PM
DIA 1 Current TO 1159 PM Current TO 1130 PM
Denver County 1 Current TO 1159 PM Current TO 1130 PM
Adams County 1 Current TO 1159 PM Current TO 1130 PM
Douglas County 3 Current TO 1159 PM Current TO 1130 PM
Broomfield County 1 Current TO 1159 PM Current TO 1130 PM
Jefferson County 1 Current TO 1159 PM Current TO 1130 PM
Boulder County 1 Current TO 1159 PM Current TO 1130 PM
Arvada 1 Current TO 1159 PM Current TO 1130 PM
Wheat Ridge 1 Current TO 1159 PM Current TO 1130 PM
Lakewood 1 Current TO 1159 PM Current TO 1130 PM

County-specific Quantitative
Precipitation Outlook
Precipitation Time 30-Minute Rainfall
and % Probability
Message
Potential
Plains      
Adams Current TO 1159 PM SUN
0.1" (70%) to 0.7" (40%) to 1.5" (15%) ISSUED
Arapahoe Current TO 1159 PM SUN
0.1" (95%) to 0.7" (50%) to 1.5" (20%) ISSUED
Boulder Current TO 1159 PM SUN
0.1" (100%) to 0.9" (80%) to 1.5" (30%) ISSUED
Broomfield Current TO 1159 PM SUN
0.1" (80%) to 0.7" (45%) to 1.5" (15%) ISSUED
Denver Current TO 1159 PM SUN
0.1" (70%) to 0.7" (40%) to 1.5" (15%) ISSUED
Douglas Current TO 1159 PM SUN
0.1" (100%) to 0.9" (60%) to 1.5" (30%) ISSUED
Jefferson Current TO 1159 PM SUN
0.1" (100%) to 0.9" (80%) to 1.5" (30%) ISSUED
Foothills above 6500ft      
Boulder Current TO 1159 PM SUN
0.1" (80%) to 0.7" (50%) to 1.5" (20%) ISSUED
Douglas Current TO 1159 PM SUN
0.1" (100%) to 0.9" (50%) to 1.5" (30%) ISSUED
Jefferson Current TO 1159 PM SUN
0.1" (90%) to 0.7" (60%) to 1.5" (25%) ISSUED
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.