Time: 823 AM Sun August 23, 2020 Forecaster: Justin Brooks

Heavy Precipitation Outlook
Flash Flood Prediction Program

CONTINUED HOT AND HAZY WITH A VERY SLIGHT CHANCE FOR HIGH-BASED AFTERNOON THUNDERSTORMS ALONG THE FOOTHILLS AND PALMER DIVIDE
-Not much has changed to the overall weather pattern as high-pressure continues to churn towards the SW today leading to near record breaking high temperatures in the 90's across the plains with mid to upper 80's along the foothills with hazy conditions continuing throughout the day.
-Likely dry most areas with a few scattered high-based rain showers/isolated thunderstorms possible in the foothills and along the Palmer Divide this afternoon. Very little precipitation is expected to reach the ground, resulting in an increased chance for dry lightning and gusty winds bringing an increased threat for fire danger as relative humidity values hover around 10% this afternoon. Best chance to see any storm development will be from 2-7pm with skies clearing out before sunset.
-Overnight lows will drop into the mid to upper 60's across the plains with mid to upper 50's along the foothills.
STORM RAINFALL POTENTIAL AND DURATION: High-based Rain showers and/or a weak thunderstorms will produce a trace to 0.05". An isolated moderate thunderstorms will have the potential to produce 0.05-0.1" in 10-30 mintues. Supplemental QPF is available at https://qpf.udfcd.org

WORST CASE SCENARIO: A moderate, slower moving thunderstorm formed off an outflow boundary may produce rainfall amounts of up to 0.3" in 45-60 minutes.

A LOOK AHEAD: High temperatures will remain above average, in the 90's, this week with rain chances increases through the week as a bit more moisture moves into the region. Best chance for rain/isolated thunderstorms will be Thursday and Friday, although the threat for any heavy rainfall will be close to zero.

Location Prime Time 30-Minute Rainfall
and % Probability
Message
Potential
Plains      
Adams 200 PM TO 700 PM
Trace (5%) to 0.1" (0%) NONE
Arapahoe 200 PM TO 700 PM
Trace (5%) to 0.1" (0%) NONE
Boulder 200 PM TO 700 PM
Trace (5%) to 0.1" (0%) NONE
Broomfield 200 PM TO 700 PM
Trace (5%) to 0.1" (0%) NONE
Denver 200 PM TO 700 PM
Trace (5%) to 0.1" (0%) NONE
Douglas 200 PM TO 700 PM
Trace (5%) to 0.1" (0%) NONE
Jefferson 200 PM TO 700 PM
Trace (5%) to 0.1" (0%) NONE
Foothills above 6500ft      
Boulder 200 PM TO 700 PM
Trace (10%) to 0.1" (10%)
Douglas 200 PM TO 700 PM
Trace (10%) to 0.1" (10%)
Jefferson 200 PM TO 700 PM
Trace (10%) to 0.1" (10%)
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.