Time: 247 PM Sun May 2, 2021 Forecaster: Brad Simmons

Internal Message Status
Flash Flood Prediction Program

MESSAGE 1'S CONTINUE VALID FOR THE DISTRICT
-Message 1's will continue valid for the District until 8:00pm and may need to be extended to 10pm...
-A round of showers and thunderstorms moved through the District earlier with just a few isolated/weak rain showers currently. Another round or two of showers and thunderstorms are likely through the afternoon/early evening with stronger storms still capable of producing brief heavy rainfall and hail.
-A widespread "wetting" rain is still expected to fill in this evening sometime between 7-10pm. If the front end of these showers are moderate to heavy in intensity then messages may need to be extended until 10pm for the threat of 1.00"/hour or more rainfall rates. Most likely these showers will result in rain rates of 0.10-0.60"/hr. As the evening progresses rainfall rates will lessen into the 0.05-0.20"/hr rate range overnight with rain changing over to snow in the Front Range foothills.
STORM RAINFALL POTENTIAL AND DURATION: Rain showers and weak thunderstorms will produce 0.1-0.3" in 10-30 minutes. Moderate to strong thunderstorms will have the potential to produce 0.3-0.8" in 10-30 minutes.

WORST CASE SCENARIO: Training of moderate/strong thunderstorm cells may result in up to 1.4" of rain in 60-90 minutes.

County Message Valid Times Prime Time
Boulder County 1 Current TO 800 PM 1100 AM TO 700 PM
Jefferson County 1 Current TO 800 PM 1100 AM TO 700 PM
Broomfield County 1 Current TO 800 PM 1100 AM TO 700 PM
Douglas County 1 Current TO 800 PM 1100 AM TO 700 PM
Adams County 1 Current TO 800 PM 1100 AM TO 700 PM
Denver County 1 Current TO 800 PM 1100 AM TO 700 PM
DIA 1 Current TO 800 PM 1100 AM TO 700 PM
Arapahoe County 1 Current TO 800 PM 1100 AM TO 700 PM
the City of Aurora 1 Current TO 800 PM 1100 AM TO 700 PM
Arvada 1 Current TO 800 PM 1100 AM TO 700 PM
Wheat Ridge 1 Current TO 800 PM 1100 AM TO 700 PM
Lakewood 1 Current TO 800 PM 1100 AM TO 700 PM

County-specific Quantitative
Precipitation Outlook
Precipitation Time 30-Minute Rainfall
and % Probability
Message
Potential
Plains      
Adams 1100 AM TO 800 PM
Trace (95%) to 0.3" (65%) to 0.8" (15%) ISSUED
Arapahoe 1100 AM TO 800 PM
Trace (95%) to 0.3" (65%) to 0.8" (15%) ISSUED
Boulder 1100 AM TO 800 PM
Trace (95%) to 0.3" (65%) to 0.8" (15%) ISSUED
Broomfield 1100 AM TO 800 PM
Trace (95%) to 0.3" (65%) to 0.8" (15%) ISSUED
Denver 1100 AM TO 800 PM
Trace (95%) to 0.3" (65%) to 0.8" (15%) ISSUED
Douglas 1100 AM TO 800 PM
Trace (95%) to 0.3" (65%) to 0.8" (15%) ISSUED
Jefferson 1100 AM TO 800 PM
Trace (95%) to 0.3" (65%) to 0.8" (15%) ISSUED
Foothills above 6500ft      
Boulder 1100 AM TO 800 PM
Trace (100%) to 0.3" (65%) to 0.8" (15%) ISSUED
Douglas 1100 AM TO 800 PM
Trace (100%) to 0.3" (65%) to 0.8" (15%) ISSUED
Jefferson 1100 AM TO 800 PM
Trace (100%) to 0.3" (65%) to 0.8" (15%) ISSUED
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.