867 FXUS65 KPUB 132357 AFDPUBArea Forecast Discussion National Weather Service Pueblo CO 557 PM MDT Sat Sep 13 2025
.KEY MESSAGES...
- Scattered storms expected this evening, some strong (especially far east).
- Some frost possible tonight and tomorrow night San Luis Valley.
- Dry and warm tomorrow.
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.SHORT TERM /THROUGH SUNDAY/... Issued at 203 PM MDT Sat Sep 13 2025
Currently...
Loyd of scattered showers over the higher terrain early this afternoon. A cluster was noted over the southern mtns and pushing onto the southern I-25 corridor while a stronger line (some severe and confirmed tornadic) was noted over the CO/UT border. Isolated activity was developing over the far eastern plains.
Rest of today...lots of deep layer shear (40-60 knts bulk) is over the region, however CAPE is also noted, but is relatively meager (500-1000J/kg). Nonetheless, strong cores were developing over the region so some of these storms will likely become strong to severe over all of the region later this afternoon. Will have to watch areas which are getting sun early this afternoon and dwpts over the plains are well into the 50s, so if better cape can be realized then the chances of severe will increase.
Overall, better forcing is expected to lift out of the region by early to mid evening, and this, along with increasing CIN, will allow storms to quickly decrease in coverage over the region
For tonight, the only sensible weather concern is the chance of frost over the San Luis Valley, and a frost advisory is in effect for most of the valley for late tonight into early tomorrow morning.
Tomorrow, except of some very isolated showers, tomorrow is going to be a mostly sunny and a bit cooler day over the region.
Tomorrow night, we may see a continued threat of patchy frost over the San Luis Valley.
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.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... Issued at 327 AM MDT Sat Sep 13 2025
Sunday Night and Monday..
Our flow aloft transitions from zonal Monday morning to southwesterly by the end of the day, as our next Low begins to take shape over the northern Rockies. This will mean a bit of a warmup from Sunday`s temperatures as we head into Monday, with daytime highs returning to slightly above normal. Highs in the 70s are expected over mountain valleys, with 80s over much of the plains, and a few low 90s over the Lower Arkansas River Valley. Showers and thunderstorms are not expected on Monday. Winds will be mainly light and terrain driven, and critical fire weather conditions are not expected.
Tuesday Onwards..
Models are beginning to show more alignment with the mid-week system, though there is still a good deal of uncertainty on timing with the Low itself. Newest model runs do show that we stay warm/above normal for Tuesday as southwest flow ahead of the system persists. Shortwaves embedded in the approaching trough also look to combine with enough moisture to bring showers and thunderstorms back to the forecast by Tuesday afternoon, though coverage looks to be fairly isolated and mainly tied to the mountains. The cold front looks to arrive somewhere in the late Tuesday or Wednesday timeframe as the low passes to our north, cooling us back down to below normal temperatures for both Wednesday and Thursday. Showers and thunderstorms look to be possible again on Wednesday, decreasing in coverage and intensity by Thursday as the low scoots east into the northern plains. Clearing conditions and northwest flow behind the system could lead to a chilly morning on Thursday. Ridging looks to build in for Friday and Saturday, along with the potential for more near normal highs.
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.AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 547 PM MDT Sat Sep 13 2025
Still a couple waves of convection moving through the region, and will keep a prob30 for -tsra at KALS and KCOS until 02z-03z, less chance at KPUB, with more a -shra risk here until 02z. Forcing for convection then shifts north after 03z, with lingering VFR cigs through the night.
Haven`t included them in the forecast yet, but a few CAMs show some lingering showers overnight (06z-12z) occasionally getting close to both KCOS and KPUB. For now, will continue with VFR cigs through the night, but no precip. On Sun, drier air spreads into the area, suppressing convection. Surface gradient will keep a north wind for much of the day, with a late switch to more typical upslope/upvalley toward 00z.
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.PUB WATCHES/WARNINGS/ADVISORIES... Frost Advisory from 3 AM to 9 AM MDT Sunday for COZ070-071.
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SHORT TERM...HODANISH LONG TERM...EHR AVIATION...HODANISH
NWS PUB Office Area Forecast Discussion