National Weather Service Forecast Discussion |
Thornton Weather Forecast Today's Forecast Story |
264 FXUS65 KBOU 061156 AFDBOU Area Forecast Discussion National Weather Service Denver/Boulder CO 556 AM MDT Mon Jul 6 2026 .KEY MESSAGES... - Hot temperatures and a few storms expected each day this week, with the highest probabilities shaping up for Tuesday through Thursday from the Front Range eastward. - Isolated dry thunderstorms in mountains could spark new wildfires. - Significant heat wave arrives this coming weekend, with minimal chance of any thunderstorms for heat relief. && .DISCUSSION /Through Sunday/... Issued at 102 AM MDT Mon Jul 6 2026 Another hot day is expected to kick off the week, with afternoon highs climbing into the mid to upper 90s across the plains while we remain under an upper-level ridge. With increasing mid-level moisture expected by this afternoon, there will be potential for some high-based showers to move off the higher terrain, but with marginal instability and inverted-v forecast soundings showing DCAPE ranging from 1200-1700 J/kg, the main expectation is for gusty outflows (35-45 mph) and little to no precipitation with the majority of anything that develops. The best chances will be along the Front Range Mountains, Palmer Divide, and Cheyenne Ridge. Clouds should diminish through the evening, and overnight temperatures are forecast to be about five to ten degrees above normal across the forecast area. The forecast remains largely unchanged for the extended period as ensembles continue to show fairly good agreement with the synoptic pattern. We are still expecting a slightly more active pattern from Tuesday to Thursday, with growing potential for a few stronger to severe storms each day as instability and shear gradually increase through the week. Slightly cooler temperatures are expected for midweek before another warming pattern starts again Friday. Ensembles do start to show some discrepancies by the end of the week with how hot temperatures will get under an anomalously high upper-level ridge. The GEFS continues to be a few degrees warmer than the ECMWF, but there is high confidence that we see multiple days of above normal temperatures, reaching for record highs next weekend and into early next week across the forecast area. Will have to continue to monitor as there is a good chance we reach Heat Advisory criteria sometime this weekend and possibly early next week. Scattered storms will be possible on Friday before stronger subsidence sets in under the ridge, suppressing any precipitation potential for the weekend. With multiple days of hot and dry weather, fuel conditions will need to be monitored closely as this would be a recipe for increasing fire weather concerns next week, particularly if winds increase or dry thunderstorms return. && .AVIATION /12Z TAFS through 12Z Tuesday/... Issued at 535 AM MDT Mon Jul 6 2026 South to south-southwesterly winds are in place at KDEN/KAPA with light and VRB winds at KBJC early this morning. Smoke is visible once again in webcams across the KDEN airfield, and suspect this will cause some slant-range visibility concerns until better mixing occurs through the morning. Main concerns for today will be similar to yesterday, with high- based showers bringing potential for gusty outflows/microbursts between 21Z-1Z. Shower coverage does look slightly more than Sunday, which could lead to some outflow boundaries passing across the airfields from both the north and south through the evening. Forecast soundings portray inverted-v profiles with DCAPE expected to range from 1500-1700 J/kg, which would support some strong microbursts (35-45kts) if a virga shower does pass over. Confidence is not high enough to include in the TAF yet, but have kept VCSH in for the timing that would have the best chances. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...9 AVIATION...9