Flash Flood Prediction Program

Message 1’s have been issued for the entire District and will be valid until 9:00pm this evening.

A few isolated, but potent showers have already developed over the Aurora area at this time. These off and on showers and likely a few thunderstorms will continue to pulse up and down through the afternoon and into the evening hours. Currently low to mid 50 dew points will result in even weak showers to produce moderate to heavy rainfall. Combined with already saturated soils will result in easy LOW IMPACT FLOODING with pooling water and rising creeks/stream likely into the evening.

Storm motions will also play a large role today as very weak steering winds aloft result in stationary storms, with pulse like behavior. Additional storms will likely form along outflow boundaries through the afternoon, also increasing chances for isolated heavy rainfall. Models indicate the best rainfall along the foothills, where storms are most likely to anchor in place; however, current conditions indicate equal chance across the District for heavy rainfall into the afternoon and evening.

STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers will produce 0.1-0.5” in 10-30 minutes. Moderate to strong thunderstorms will have the potential to produce rainfall rates of 0.5-1.5” in 10-30 minutes.

WORST CASE SCENARIO: A slow-moving strong thunderstorm or nearly stationary thunderstorm may result in up to 2.2” of rain in 60 minutes or less.

County	Message	Valid Times	Prime Time
Adams County	1	Current TO 900 PM	Current TO 830 PM
Denver County	1	Current TO 900 PM	Current TO 830 PM
DIA	1	Current TO 900 PM	Current TO 830 PM
Arapahoe County	1	Current TO 900 PM	Current TO 830 PM
the City of Aurora	1	Current TO 900 PM	Current TO 830 PM
Arvada	1	Current TO 900 PM	Current TO 830 PM
Wheat Ridge	1	Current TO 900 PM	Current TO 830 PM
Broomfield County	1	Current TO 900 PM	Current TO 830 PM
Lakewood	1	Current TO 900 PM	Current TO 830 PM
Douglas County	1	Current TO 900 PM	Current TO 830 PM
Jefferson County	1	Current TO 900 PM	Current TO 830 PM
Boulder County	1	Current TO 900 PM	Current TO 830 PM

County-specific Quantitative Precipitation Outlook	Precipitation Time	30-Minute Rainfall and % Probability	Message Potential
Plains
Adams	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Arapahoe	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Boulder	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Broomfield	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Denver	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Douglas	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Jefferson	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Foothills above 6500ft
Boulder	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Douglas	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED
Jefferson	Current TO 900 PM MON	0.1" (75%) to 0.5" (50%) to 1.5" (25%)	ISSUED

MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.