Time: 934 AM Fri June 30, 2023 Forecaster: Justin Brooks ------------------------- Internal Message Status Flash Flood Prediction Program ------------------------- MESSAGE 1’S HAVE BEEN ISSUED FOR THE ENTIRE DISTRICT Message 1’s have been issued for the entire District effective until 6pm. Storms have initiated 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 with the largest threat being a quick 0.5” in 10-15 minutes. Typical storm movements will be from W/NW to E/SE 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 with storms likely decreasing into the evening with skies clearing this evening. 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 1.5”, 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. COUNTY MESSAGE VALID TIMES PRIME TIME Adams County 1 Current TO 600 PM Current TO 530 PM Douglas County 1 Current TO 600 PM Current TO 530 PM Broomfield County 1 Current TO 600 PM Current TO 530 PM Jefferson County 1 Current TO 600 PM Current TO 530 PM Boulder County 1 Current TO 600 PM Current TO 530 PM Denver County 1 Current TO 600 PM Current TO 530 PM DIA 1 Current TO 600 PM Current TO 530 PM Arapahoe County 1 Current TO 600 PM Current TO 530 PM the City of Aurora 1 Current TO 600 PM Current TO 530 PM Arvada 1 Current TO 600 PM Current TO 530 PM Wheat Ridge 1 Current TO 600 PM Current TO 530 PM Lakewood 1 Current TO 600 PM Current TO 530 PM County-specific Quantitative Precipitation Outlook PRECIPITATION 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%) ISSUED Arapahoe Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED Boulder Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED Broomfield Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED Denver Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED Douglas Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED Jefferson Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED Foothills above 6500ft       Boulder Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED Douglas Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED Jefferson Current TO 600 PM FRI 0.25" (90%) to 0.5" (60%) to 1.5" (30%) ISSUED MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS. MHFD Flood Prediction Center: 303-458-0789    F2P2 Website [http://udfcd.org/Flash+Flood+Prediction+Program]