| - | The National Weather Service in Boulder has issued a Flash Flood Watch for the higher terrain of Boulder County above 6,000ft from 11am until 9pm this evening. The Flash Flood Watch is primarily issued for the Calwood burn area of Boulder County. Although the flood threat is lower outside the Calwood burn area the Message 2 will cover areas within the MHFD as a portion of the District is included in the NWS zone. Message 1's will go into effect at noon for all other Counties within the District. |
| - | Thunderstorms will begin to initiate over the higher terrain between noon and 2pm. Upper level steering winds from SW to NE at 10-15mph will push the storm activity onto the plains during the early afternoon. Prime time for thunderstorms is between 1-8pm. Relatively slow storm motions and ample moisture to fuel thunderstorms will result in stronger storms capable of producing heavy rainfall that may lead to excessive runoff and possibly flash flooding. |
| - | The main culprit for extended periods of heavy rainfall today will be storms that are able to anchor or move more slowly. Training of thunderstorm cells is less likely but cannot be ruled out over the foothills. East of I-25 stronger storms may become severe with large hail and gusty winds being the primary threats as well as heavy rainfall. |
WORST CASE SCENARIO: A large thunderstorm complex or a nearly stationary strong thunderstorm cell may result in up to 2.5" of rain in 60-90 minutes.
| County-specific Quantitative Precipitation Outlook |
Precipitation Time | 30-Minute Rainfall and % Probability |
Message Potential |
|---|---|---|---|
| Plains | |||
| Adams |
200 PM TO
900 PM |
0.1" (90%) to 0.5" (60%) to 1.5" (25%) | |
| Arapahoe |
200 PM TO
900 PM |
0.1" (90%) to 0.5" (60%) to 1.5" (25%) | |
| Broomfield |
200 PM TO
900 PM |
0.1" (90%) to 0.5" (60%) to 1.5" (20%) | |
| Denver |
200 PM TO
900 PM |
0.1" (90%) to 0.5" (60%) to 1.5" (20%) | |
| Boulder |
100 PM TO
900 PM |
0.1" (90%) to 0.5" (60%) to 1.5" (20%) | |
| Douglas |
100 PM TO
900 PM |
0.1" (90%) to 0.5" (60%) to 1.5" (20%) | |
| Jefferson |
100 PM TO
900 PM |
0.1" (90%) to 0.5" (60%) to 1.5" (20%) | |
| Foothills above 6500ft | |||
| Boulder |
1200 PM TO
900 PM |
0.1" (95%) to 0.5" (65%) to 1.5" (20%) | |
| Douglas |
1200 PM TO
900 PM |
0.1" (95%) to 0.5" (65%) to 1.5" (20%) | |
| Jefferson |
1200 PM TO
900 PM |
0.1" (95%) to 0.5" (65%) to 1.5" (20%) |
MONITOR NATIONAL WEATHER SERVICE FOR SEVERE WEATHER STATEMENTS.