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690 FXUS65 KBOU 150535 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 1135 PM MDT Sun Jun 14 2026 .KEY MESSAGES... - Cool today with scattered showers/thunderstorms mainly along and south of I-70. - Temperatures heat back up next week potentially reaching the upper 90s across the plains on Wednesday. - Increasing fire weather concerns on Tuesday with widespread critical fire weather conditions possible on Wednesday. && .DISCUSSION /Through Sunday/... Issued at 219 PM MDT Sun Jun 14 2026 Water vapor imagery shows a shortwave trough over eastern Wyoming currently with a stream of mid level moisture across the I-70 corridor in Colorado. Visible satellite shows low clouds have been persistent across northeast Colorado mainly to the north of I-70 although they have been clearing some this afternoon. Some forcing from the shortwave trough and some instability across the central mountains of Colorado will allow for showers and storms to form this afternoon and evening. The best chance for storms will be along and south of I-70 where it was sunnier than areas to the northern for most of the day. These storms are expected to be sub-severe. On Monday, our forecast area will be under light subsident flow with drying conditions throughout the low levels. High temperatures across the plains will be slightly cooler than normal with mostly sunny skies. A jet streak will move over the northwestern US Tuesday and Wednesday. This jet stream will generally be positioned from Vancouver to Nebraska and Colorado will be under the right exit region leading to strong subsidence. This will result in rapidly warming temperatures and drying conditions. This leads to two concerns and those are heat impacts and increased fire danger. Tuesday will be warm but heat impacts will be limited. The high will be around 90 across most of the plains. On Wednesday, if a cold front that will likely come through during the evening holds off, temperatures could reach the upper 90s across the plains. However, there is a small chance (20%) that the cold front comes through early enough to reduce the high temperature by 5-10 degrees. The fire weather concerns will also depend on the cold front timing. If the cold front is slow to arrive, strong northwest winds will gust up to 35 to 40 mph across the plains and with relative humidity around 6-10 percent, there would be critical fire weather conditions. If the front arrives earlier throughout the day, humidity will not be as low and critical fire weather conditions may be avoided. However, the most likely scenario (80%) appears to be widespread critical fire weather conditions given the strong winds and low relative humidity. Thursday will be cooler before hot temperatures arrive on Friday and Saturday again. Ensemble guidance still shows a wet period Sunday through Tuesday but I`ll believe it when I see it. && .AVIATION /06Z TAFS through 06Z Tuesday/... Issued at 1122 PM MDT Sun Jun 14 2026 Upslope winds have continued to keep stratus in place across the TAF sites late tonight. Winds are expected to transition to a more southerly component in the next few hours, between 7Z-8Z, that will start to breakup the lower CIGs and bring significant improvements, likely scattering out fairly quickly after the winds shift. VFR conditions are expected to then prevail through the rest of the TAF period. Winds are expected to become light and variable between 12Z-14Z before settling into a northeasterly flow by 18Z through the afternoon and early evening. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Danielson AVIATION...9