Time: 854 AM Fri June 30, 2023 Forecaster: Justin Brooks ------------------------- Heavy Precipitation Outlook Flash Flood Prediction Program ------------------------- ANOTHER DISTURBANCE MOVING THROUGH THE REGION THIS MORNING REULTING IN ISOLATED AM SHOWERS/THUNDERSTORMS Storms early this morning, with another stronger round expected this late this morning and into the afternoon hours. Storms this morning could possibly produce some brief moderate to heavy rain, especially if a storm produces an outflow boundary which has the potential to initiate additional storms. Typical storm movements will be from west to east between 10-20mph which should help limit point rainfall amounts. However, with low to mid 50 dew points, a stalled out storm formed along an outflow boundary will have the potential to produce localized heavy rainfall. The best chance for storm activity will be from now through the late afternoon/early evening with storms likely decreasing into the evening with skies clearing by midnight tonight. A chance for isolated heavy rain this morning, with a better chance for widespread storms along the I-25 corridor during the afternoon. Some of these storms could become severe with large hail up to 2”, gusty winds 60+mph, frequent cloud-to-ground lightning. A weak land spout/tornado cannot be completely ruled out, favoring areas east of I-25. STORM RAINFALL POTENTIAL AND DURATION: Typical rain showers/isolated thunderstorms will produce 0.25-0.50” total, in 10-30 minutes. A moderate to heavy thunderstorm could produce 0.50-1.50” total, in 10-30 minutes. WORST CASE SCENARIO: A stationary strong thunderstorm, or training of thunderstorm cells has the potential to produce 2.50” in 45-60 minutes. A LOOK AHEAD: This severe weather pattern will shift tomorrow, resulting in a less chance for strong storms with the potential for large hail, gusty winds and an isolated tornado decreases significantly. More typical afternoon showers/thunderstorms will be possible both Saturday and Sunday. A slight chance low-level moisture remains elevated tomorrow which could bring at least a LOW chance for Message 1’s Saturday. LOCATION PRIME TIME 30-Minute Rainfall and % Probability Message Potential Plains       Adams Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Arapahoe Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Boulder Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Broomfield Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Denver Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Douglas Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Jefferson Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Foothills above 6500ft       Boulder Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Douglas Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH Jefferson Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) HIGH MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]