Time: 1028 AM Sun May 26, 2019 Forecaster: Justin Brooks

Heavy Precipitation Outlook
Flash Flood Prediction Program

SCATTERED AFTERNOON THUNDERSTORMS WITH BRIEF HEAVY RAIN POSSIBLE
-Surface moisture has increased from previous days with dew points expected to be in the mid 40's to around 50. The modest surface moisture will allow for some storms to produce brief heavy rainfall which may lead to excessive runoff, favoring areas east of I-25.
-Thunderstorms will initiate over the foothills after noon and then spread northeastward onto the plains. Storms will be relatively fast moving from SW to NE at 15-25mph with one to three rounds of storms likely through the early evening.
-Temperatures will reach the upper 70's to low 80's over the plains before cloud cover increases this afternoon. Strong SW flow and an upper level disturbance over western Colorado this morning will move through the District this afternoon and produce scattered showers and thunderstorms some of which may become severe and capable of producing brief heavy rainfall, gusty winds and hail.
STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers and weak to moderate thunderstorms will produce 0.1-0.4". Strong thunderstorms will have the potential to produce up to 0.4-1.0" in 10-30 minutes.

WORST CASE SCENARIO: A slower moving strong thunderstorm or training of strong thunderstorm cells may result in up to 2.2" in 60-90 minutes.

A LOOK AHEAD: An active weather pattern will remain in place through this week resulting in a chance for afternoon/evening showers Monday, although chances for severe weather will be greatly reduced. Temperatures will be mild Monday, in the low to mid 70's, before a cold front pushes through Tuesday which will drop high temperatures into the mid to upper 50's with off and on showers during the day Tuesday and into Wednesday.

Location Prime Time 30-Minute Rainfall
and % Probability
Message
Potential
Plains      
Adams 200 PM TO 800 PM
Trace (80%) to 0.3" (50%) to 0.6" (30%) MOD
Arapahoe 200 PM TO 800 PM
Trace (80%) to 0.3" (50%) to 0.6" (30%) MOD
Boulder 200 PM TO 800 PM
Trace (80%) to 0.3" (50%) to 0.6" (30%) MOD
Broomfield 200 PM TO 800 PM
Trace (80%) to 0.3" (50%) to 0.6" (30%) MOD
Denver 200 PM TO 800 PM
Trace (80%) to 0.3" (50%) to 0.6" (30%) MOD
Douglas 200 PM TO 800 PM
Trace (80%) to 0.3" (50%) to 0.6" (30%) MOD
Jefferson 200 PM TO 800 PM
Trace (80%) to 0.3" (50%) to 0.6" (30%) MOD
Foothills above 6500ft      
Boulder 200 PM TO 800 PM
Trace (80%) to 0.3" (30%) to 0.6" (10%) LOW
Douglas 200 PM TO 800 PM
Trace (80%) to 0.3" (30%) to 0.6" (10%) LOW
Jefferson 200 PM TO 800 PM
Trace (80%) to 0.3" (30%) to 0.6" (10%) LOW
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.