textproduct: Pueblo

KEY MESSAGES

- One more day of widespread showers and thunderstorms over the mountains on Friday, with pockets of heavy rainfall again possible. - Thunderstorm activity may then increase over the plains late Saturday into Sunday as a cold front moves through the area.

- A bit drier late Saturday into Sunday over the mountains, before cooler and possibly wetter conditions return next week.

SHORT TERM /THROUGH FRIDAY/

Issued at 135 PM MDT Thu Sep 17 2026

Currently, initial s/w trough which brought widespread showers to many locations overnight/early this morning was lifting into nrn CO, with a pronounced downturn in precip across the area early this afternoon. Still some light to briefly moderate rain in spots along the Continental Divide as of 130 pm, but overall, next round of thunderstorm development has been slowed by clouds and weak subsidence behind the departing wave. Most models suggest storm redevelopment after 3 pm, with ern San Juans/srn San Luis Valley and the srn Sangres looking most favored for stronger activity as convection moves northward out of NM. Peak storm coverage according to many CAMs may not come until 6-7 pm, with even some weakening activity drifting into the I-25 corridor possible. Will keep flash flood watch up until midnight for the sw mountains, where models suggest heavier rain is possible through at least sunset. Overnight, convection diminishes greatly after midnight, with only some lingering showers along the Continental Divide into Fri morning. On Fri, one more day of widespread mountain showers/thunderstorms expected, as Pacific NW upper low begins it's eastward trek into the Rockies. Best storm coverage again along the Continental Divide, with mainly isolated storms from I-25 eastward. Max temps will nudge upward, with some low/mid 90s over the southeast plains.

LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/

Issued at 135 PM MDT Thu Sep 17 2026

On Saturday, upper low moves into wrn WY, with strengthening wly flow over CO bringing in a drier air mass, especially over the mountains. While we won't shut off convection completely as upper trough extending south from the WY low will provide some modest upward motion, storm coverage/strength will be lower than the past few days over most of the higher terrain Sat afternoon and evening. For the eastern mountains and southeast plains, forecast hinges on how fast cold front arrives and how much low level instability develops behind it by late day. Most model forecasts have boundary near the Arkansas River by late Sat afternoon, then progressing south toward the NM border through the evening. Combination of best upper forcing and greatest low level instability are currently forecast over nern CO Sat afternoon/evening, though instability/shear over sern CO look more than sufficient for storms to build s-sw into the area, especially mid to late evening. Nudged up NBM pops a bit Sat afternoon/evening to account for this scenario, though overall blended guidance didn't look too bad for this period.

Strong wly flow aloft on Sun will dry out the mountains, with convection limited to the ern slopes of the Sangres/Wets/Pikes Peak. For the I-25 corridor and the sern plains, post frontal upslope will persist, keeping dewpoints in the 50s east of I-25 through the day. 0-6km shear of 35-45 kts will be in place, with models showing CAPE in the 1k-2k J/KG range from afternoon into the evening, while 70-80 kt jet streak at 250 moves overhead late in the day. Set-up looks favorable for strong/severe storms east of the mountains, though outflow and potential cloud cover from Sat night/early Sun morning storms could limit instability, especially into early/mid afternoon. Current forecast has mainly isolated pops over the plains Sun afternoon, then widespread storms along/east of I-25 Sun evening as activity initially along the Palmer intensifies and expands south and east. Max temps behind the front on Sun will run 5-10 degf cooler than Sat, while mountains see little change.

Low confidence forecast for Mon-Wed as model solutions have bounced around a good deal, though rough consensus appears to favor a return of low/mid level moisture to much of the area as we approach mid-week, with western U.S. upper trough/sern U.S. upper ridge pattern potentially reforming. Blended model guidance shows cooler than average temperatures and daily chances for showers/thunderstorms, which looks fine for now.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1141 AM MDT Thu Sep 17 2026

KCOS and KPUB: VFR conditions the next 24 hrs, with a prob30 for a brief -tsra from late this afternoon into early this evening. S-SW winds will increase at both terminals this afternoon, with gusts to 20-25 knots expected. Winds then decrease overnight into Friday morning.

KALS: VFR conditions are expected over the next 24 hours, with a prob30 for -tsra from late this afternoon into this evening. The main storm threats will be gusty winds to 35 kts and and brief heavy rainfall. VCSH will linger until around 08z, then most precip shifts east of the area. S-SW winds will remain gusty (20-25 kts) this afternoon, before diminishing this evening and overnight.

PUB WATCHES/WARNINGS/ADVISORIES

Flood Watch until midnight MDT tonight for COZ067-068.