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578 FXUS65 KBOU 040027 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 627 PM MDT Thu Jul 3 2025 .KEY MESSAGES... - Scattered thunderstorm activity over the mountains this evening with a slight chance over the plains tonight into Friday morning. - Less numerous, scattered showers and thunderstorms are expected Friday afternoon, diminishing from west to east in the evening. - A chance of afternoon and evening thunderstorms and above normal temperatures are expected for the weekend into early next week. && .DISCUSSION /Through Thursday/... Issued at 239 PM MDT Thu Jul 3 2025 Thunderstorms have developed over western Colorado, but are slow to spread east so far this afternoon as the storm motions are south to north. This area of convection will creep eastward through this evening, and eventually most of the mountains should have some showers. It`s questionable if there will be anything east of the mountains this evening, however. The main threat will be gusty winds, though a few spots could get a brief heavy rain. As the shortwave trough moves eastward, it should interact with the moisture on the plains later tonight into Friday morning. This will likely produce another batch of showers and thunderstorms. If they`re able to develop along the I-25 corridor it would likely be just before or around sunrise, then the threat out on the northeast plains is in the morning hours. There may be enough CAPE/moisture for a few strong storms in the northeast corner if the timing is slow enough (late morning), but the severe threat looks low. For later in the day, the winds aloft will become more northwesterly with some drying and a little cooling. There will likely still be some afternoon convection, although it might not be much. With continued drying into the evening, the activity will likely be over for the mountains and I-25 corridor by sunset, or at least pretty minimal coverage. The models continue with subtle day to day changes with a low amount of moisture around and temperatures a little above the hot summer normals. There`s not great confidence on how the details will affect convective trends, but it looks like there will be increasing moisture coming into the northeast plains Saturday afternoon which could be a focus for a few strong to severe storms. Model soundings suggest 1000-1500 J/kg of CAPE with sufficient shear for supercell structures. The theme for the next week will be a gradually strengthening ridge over the Rockies. But a shortwave passing over the northern Rockies about Sunday may restrain the warming and force some convection Sunday and Monday. The ridge is more likely to strengthen near us by the middle of the week. && .AVIATION /00Z TAFS through 00Z Saturday/... Issued at 624 PM MDT Thu Jul 3 2025 Models keep southeasterlies going at DIA this evening, with drainage winds kicking in by 04Z/05Z. Some of the models bring a surge of northerly winds in after midnight associated with an upper trough. Some also showing scattered convection possible so will keep the PROB30 group in for -SHRA after 10Z. Will also leave in a PROB30 group for afternoon convection on Friday. There will be no ceiling issues. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Gimmestad AVIATION.....rjk