Time: 902 AM Tue May 19, 2020 Forecaster: Justin Brooks

Heavy Precipitation Outlook
Flash Flood Prediction Program

WARM TODAY WITH A CHANCE OF A HIGH BASED SHOWERS/ISOLATED THUNDERSTORMS
-High-pressure starts to break down over the region today as a strong low-pressure trough slowly moves over the region over the next few days. Sunny and dry conditions this morning with a good chance for quick moving high-based rain showers/isolated thunderstorms this afternoon and early evening.
-High temperatures today will be in the mid to upper 80's across the plains. Gusty southerly wind this afternoon will lead to fairly quick S to N storm movement between 10-20mph which will limit point rainfall amounts and keep the flooding threat to none. Best chance for rain showers/isolated thunderstorms will be from 2-9pm with skies clearing into the overnight.
-Overnight lows will drop into the mid to upper 50's across the plains. Another chance tomorrow for rain showers/isolated thunderstorms, although favoring the eastern plains, a storm developing along the I-25 corridor cannot be ruled out at this time.
STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers and weak to moderate thunderstorms will produce a trace to 0.1" in 10-30 minutes. A strong thunderstorm will have the potential to produce 0.2-0.5" in 10-30 minutes.

WORST CASE SCENARIO: A slower moving strong thunderstorm or training of moderate/strong thunderstorm cells may result in up to 1.0" of rain in 30-60 minutes.

A LOOK AHEAD: A more active weather pattern will be in place over the next few days bringing a chance for rain showers/isolated thunderstorms during the afternoon and evening both Wednesday and Thursday, although the flood threat remains minimal at this time. High-pressure slowly returns Friday bringing drier conditions into the weekend.

Location Prime Time 30-Minute Rainfall
and % Probability
Message
Potential
Plains      
Adams 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Arapahoe 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Boulder 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Broomfield 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Denver 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Douglas 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Jefferson 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Foothills above 6500ft      
Boulder 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Douglas 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
Jefferson 200 PM TO 900 PM
Trace (50%) to 0.1" (30%) to 0.5" (5%) NONE
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.