Time: 846 AM Tue May 23, 2023 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- HAZY AGAIN THIS MORNING WITH MOSTLY DRY CONDTIONS THIS AFTERNOON The weak ridge of high-pressure will slowly start to break down today as a more active weather pattern starts to take hold over the region through the rest of the week. Upper-level winds will shift more westerly into the afternoon, which could help limit storm activity today. However, a slight chance will remain for a few rain showers/isolated thunderstorms, mainly for the foothills and along the Palmer Divide. Any showers that do develop will generally be high based, resulting in minimal rain along the foothills and Palmer Divide this afternoon and early evening. A very slight chance any of these showers make their way onto the plains as surface dewpoints are once again expected to mix out into the upper 30’s to around 40 degrees this afternoon. Overnight lows will drop into the upper 40's to around 50 degrees on the plains with low to mid 40’s along the foothills. Mild and dry conditions expected through the overnight and into Wednesday. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers will produce TR-0.10" in 10-30 minutes. A weak to moderate thunderstorm will have the potential to produce rainfall rates of 0.10-0.30" in 10-30 minutes. WORST CASE SCENARIO: A slow moving or stationary thunderstorm, or training of rain showers/thunderstorms may result in rainfall rates of up to 0.6" in 45-60 minutes. A LOOK AHEAD: A much better chance for widespread rain showers and thunderstorms tomorrow afternoon and early evening with a slight chance some of the storms become severe, favoring areas east of I-25 at this time. A few linger showers possible through midnight, with skies gradually clearing through the overnight. Upper-level winds shift NW Thursday, with elevated surface moisture and decent upper-level support, another good chance for widespread rain showers/thunderstorms Thursday afternoon and evening as well. A decreased chance for severe weather, however a couple of strong thunderstorms cannot be completely ruled out. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams 300 PM TO 800 PM Trace (30%) to 0.1" (15%) to 0.3" (5%) NONE Arapahoe 300 PM TO 800 PM Trace (30%) to 0.1" (15%) to 0.3" (5%) NONE Boulder 300 PM TO 800 PM Trace (40%) to 0.1" (20%) to 0.3" (10%) NONE Broomfield 300 PM TO 800 PM Trace (30%) to 0.1" (15%) to 0.3" (5%) NONE Denver 300 PM TO 800 PM Trace (30%) to 0.1" (15%) to 0.3" (5%) NONE Douglas 300 PM TO 800 PM Trace (40%) to 0.1" (20%) to 0.3" (10%) NONE Jefferson 300 PM TO 800 PM Trace (40%) to 0.1" (20%) to 0.3" (10%) NONE Foothills above 6500ft       Boulder 200 PM TO 700 PM Trace (50%) to 0.1" (25%) to 0.3" (10%) NONE Douglas 200 PM TO 700 PM Trace (50%) to 0.1" (25%) to 0.3" (10%) NONE Jefferson 200 PM TO 700 PM Trace (50%) to 0.1" (25%) to 0.3" (10%) NONE MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]