SHORT TERM /Through Saturday/
Issued at 219 PM MDT Fri Jul 26 2024

While smoky skies have lingered into the afternoon along the Front Range, associated air quality has improved over the past few days.
With the shifting wind patterns aloft transitioning to a more westerly pattern later today, continued improvements are expected.
The only caveat is whether the W/WSW flow starts to bring in smoke from the wildfires currently burning in California. The latest run of the HRRR Vertically Integrated Smoke shows a hefty plume of high concentrations expected to enter western WY and southwestern Utah in the next day. This will continue to be monitored in the coming days. The shifting pattern will also be responsible for increased moisture across the forecast area today and tomorrow.
Current satellite imagery shows a plume of mid- and low- level moisture extending from the Baja region into central and eastern Canada and passing directly through Colorado. Slow moving storms have already developed over the mountains early this afternoon.
SPC mesoanalysis currently shows PWAT values between .7" to .8" across the forecast area. These storms are expected to be scattered in nature and the HRRR indicates a 40% chance that some of the stronger storms may contain pockets of .25"/hr accumulations. The HRRR LPMM accumulated precipitation portrays our areas of greatest concern for heaviest rainfall to be in portions of central Larimer County, and southern Clear Creek/northern Park Counties between the 2-5 PM time frame. The storms in Larimer County may develop or pass over some of our burn scars and will be monitored for flash flooding concerns. With forecast soundings showing DCAPE values surpassing 1000 J/kg, gusty outflows are expected with these storms as they move east off the higher terrain and begin to dissipate over the lower and less favorable environment across the plains. Gusts are expected to be in the 30-35 mph range with a chance of a few gusts surpassing that with the stronger storms. Overnight temperatures are forecast to be in the 60s across the plains and 40s for the higher elevations.

Tomorrow will bring another round of scattered to numerous storms and showers. With more instability expected, there is a better chance of these storms making their way onto the plains than today's. With the increased instability and some better shear, these storms have a better chance of becoming slightly more organized which could bring increased chances for producing some hail, mainly for the northeastern portion of the forecast area.
High temperatures are expected to surpass the 90s once again across the plains and high 70s/low 80s for the mountains. Expected cloud coverage should help take the edge of the heat in the afternoon.



LONG TERM /Saturday night through Friday/
Issued at 219 PM MDT Fri Jul 26 2024

At this point in time with the upcoming heat we're trying to define if it'll be 98 degrees, not the band, or 100 degrees across the urban corridor and 100 to 105 degrees over the plains from Monday through Wednesday of next week. Ensemble probabilities have been showing the signal for 100F for several days now with probabilities inching higher as of today. Tuesday and Wednesday look to be the hottest days with the coarser ensemble data showing a 60-70% chance of reaching 100F from the Denver Metro to the north and east across the plains. That is not to say that the other days during the long term period aren't hot, they are just not as hot.

Though not a definite correlation, the last time across the metro area and plains to make a run at three consecutive days of 100F, just two weeks ago, 500mb heights were 594dm. At this time we're seeing a 90+% chance of having heights exceed that level on numerous pieces of ensemble guidance. Some moisture does try to increase later in the period, even with these deeper heights, but cloudiness could keep us a degree or two cooler by Thursday and Friday of next week. Any shower or storm activity looks to be confined to the higher terrain as well, again late period.

AVIATION /18Z TAFS through 18Z Saturday/
Issued at 1141 AM MDT Fri Jul 26 2024

Storms have developed over Jefferson County and are slowly moving east towards BJC. These storms may be associated with gusty winds reaching 35 kts at times. Some stronger storms may even contain localized gusts up to 45 kts through the afternoon and early evening. These storms are expected to continue eastward and bring gusty winds to DEN and APA in the coming hours. Tomorrow will see a similar pattern as today with afternoon thunderstorms and gusty outflow winds expected at all TAF sites. Guidance indicates tomorrow's wind gusts may be slightly higher than today's.

FIRE WEATHER
Issued at 219 PM MDT Fri Jul 26 2024

Elevated to critical fire conditions will be in place over the higher terrain both Sunday and Monday due to gusty winds, low humidity and above normal temperatures. Across the plains winds will be lighter, however, hot and dry conditions will lead to elevated fire conditions.

HYDROLOGY
Issued at 219 PM MDT Fri Jul 26 2024

Slow moving storms this afternoon and evening are expected over the high country, with a chance of some making their way to adjacent lower elevations. With increased moisture across the low to mid- levels, some localized heavy rainfall is possible. The main concern is the limited threat of flash flooding over the burn scars, mainly for those residing in Larimer County.

Enough moisture will remain across the region on Saturday for another round of showers and thunderstorms. There will again, be a limited threat for flash flooding in the burn scars. Hot and dry conditions are the main concerns Sunday through the end of the new work week.

BOU WATCHES/WARNINGS/ADVISORIES
None.