textproduct: Pueblo

KEY MESSAGES

- Periods of rain and embedded thunderstorms will spread across the Mountains and into the Plains this afternoon and overnight.

- Heavy rainfall expected Tuesday through Thursday across the Plains, and a Flash Flood Watch is now in effect for areas along the New Mexico border.

- Cooler through Thursday, drying out and warming up by the weekend.

SHORT TERM /THROUGH TONIGHT/

Issued at 1234 AM MDT Mon Sep 28 2026

Currently...quiet conditions have spread across much of southern Colorado early this morning, with a few light echoes beginning to show up on radar over the San Juan Mountains. This activity looks to pick up heading through sunrise. Temperatures across the Plains are in the upper 50s to lower 60s, and moisture is slowly increasing across the area.

Today and tonight...an upper low is forecast to dig across southern California and into western Arizona through tonight. This will keep persistent southwest flow across Colorado with increasing tropical moisture associated with the remnants of Polo beginning to spread into the area. Waves of embedded energy and PWAT values increasing to in excess of an inch will lead to rounds of precipitation across the region. Its already starting across the San Juans, and will continue with periods of moderate to heavy rainfall through tonight. Most high-res guidance spreads showers and embedded thunderstorm activity east by mid afternoon into the I-25 corridor, and continues with periods of rain into the overnight hours. Southerly flow will continue to increase moisture across the region, and and showers should become more efficient precipitation producers. Snow levels look to remain high, with a couple inches possible above 12 kft across the Mountains (mainly San Juans) through tonight. A Flash Flood Watch remains in effect for the San Juan Range this morning through the overnight period.

Temperatures today will remain warm on the Plains, with 70s to near 80 degrees, and 60s for the San Luis Valley. Lows tonight will fall into the mid 50s to low 60s on the Plains, and 40s for the San Luis Valley.

LONG TERM /TUESDAY THROUGH SUNDAY/

Issued at 1234 AM MDT Mon Sep 28 2026

Still large discrepancies in the model guidance with QPF amounts through Thursday. The 18z runs of the ECMWF and GFS were vastly different with a drier GFS and very wet ECMWF. A quick look at the 00z guidance shows a downward trend with the ECMWF (although still producing a lot of rainfall), and strengthening of the flow around the ejecting upper low.

Tuesday through Thursday...there is better agreement between the 00z guidance than the previous runs. The ECMWF has trended timing more in line with the GFS, but the storm track is still west over Colorado and not south over the Texas Panhandle.

The ECMWF, various AI versions of the guidance and NBM/DESI still on track for heavy precipitation during this period, mainly along and south of Highway 50. These solutions track the upper low from Arizona, across New Mexico and lift it north across eastern Colorado. Abundant tropical moisture embedded in the upper low from remnants of Polo will wrap around the low, with strong forcing and deep upslope flow for an extended period of time into the Raton Ridge. Winds through 500 mb are northeasterly around the upper low as it ejects northward, with heavy precipitation forecast along the southern Sangres, east along the Raton Ridge and New Mexico border, with a bulk of the heavy precipitation falling on Tuesday through Wednesday morning. QPF forecast amounts of 1 to 3 inches, with locally higher amounts are possible, with the ECMWF having the highest totals. The 00z ECMWF has a quicker ejection of the upper low into the Central Plains on Thursday, with precipitation departing the area by Friday morning.

Now for the GFS and Canadian guidance. Both solutions track the upper low from southern Arizona, across New Mexico and into the Texas Panhandle. This guidance keeps a bulk of the precipitation south, with much stronger northerly flow across our Colorado Plains Wednesday and Wednesday night. This strong northerly flow would produce a downslope effect for much of the Colorado Plains, and limit precipitation potential. In fact, this would bring very little precipitation to the Pueblo area compared to the ECMWF (GFS only has 0.2 inches, the ECMWF nearly 3 inches, and NBM around 2.5 inches). Given the GFS being an outlier, have followed the ECMWF and NBM solutions during this period.

A Flash Flood Watch has been issued for portions of the Plains where the highest confidence lies. Areas along the New Mexico border are included along with the Southern Sangre de Cristo range. DESI probabilities of 3+ inches are around 40-60 percent in this area. For areas north (along the Highway 50 corridor) we will have to see how model guidance trends for any northward expansion of the watch.

Snow levels continue to look high; above 12 kft, where several inches may be possible Tuesday through Thursday.

Temperatures will be cooler during this period, with Plains mainly in the 50s and 60s, with the coolest days Wednesday and Thursday.

Friday through Monday...given the uncertainty in the nearer term, there is a bit better agreement over the weekend into early next week. The upper system will track east, with high pressure building over the Great Basin. This will allow for drying conditions and rebounding temperatures. Highs will warm back into the 70s over the weekend into Monday.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 532 AM MDT Mon Sep 28 2026

Showers will spread across the area today and tonight, with vcsh at all sites this morning into early afternoon, then -shra becoming prevailing after 18z-21z. Cigs stay mostly VFR at KCOS and KPUB the next 24 hrs, though some brief periods of MVFR cigs/vis will be possible late this afternoon and overnight with any heavier showers. At KALS, VFR this morning, then MVFR this afternoon as showers become more prevalent. MVFR cigs/vis then continue overnight, with periods of IFR possible with any heavier precip. Low chance (10-20 percent) of a brief -tsra at all sites after 21z, though haven't included a mention in any taf at this point. S-SW winds will increase at all stations after about 18z, with some gusts 20-25 kts until early evening.

PUB WATCHES/WARNINGS/ADVISORIES

Flood Watch through late Tuesday night for COZ067-068. Flood Watch from Tuesday morning through Wednesday afternoon for COZ074-075-087-088-094-098-099.