000 FXUS65 KPUB 260532 AFDPUB Area Forecast Discussion National Weather Service Pueblo CO 1032 PM MST Mon Jan 25 2021 .UPDATE... Issued at 724 PM MST Mon Jan 25 2021 Based on latest HRRR and 00z NAM, plus persistent snow over nrn El Paso County, will expand Winter Wx Advisory to include the entire I-25 corridor and also the srn Sangres. Snow amounts on the low end of the advisory range, but with heavier snow falling over much of the area during/near the morning commute, impacts could be more significant. Other than adding the advisory and making some minor adjustments to snow amounts, forecast is in pretty good shape and won`t be making any major changes. && .SHORT TERM...(This evening through Tuesday) Issued at 250 PM MST Mon Jan 25 2021 ...More snow expected across southern Colorado tonight and Tuesday... First storm has pulled east of the area with wrap around snow continuing across the northeast portions of the forecast area...across Kiowa county. Roads have stayed fairly clear in spite of some moderate snowfall at times. This band will pull off to the northeast late this afternoon through the evening. Meanwhile, convective snow showers have developed across the mountains this afternoon which will continue to expand and become more widespread as southern Colorado comes under the influence of the next upper low across southern CA, which will lift northeastward through the Desert Southwest towards the 4 corners region tonight, then across southern Colorado on Tuesday. System develops 2 circulation centers as it crosses the mountains Tuesday morning and the leading impulse tightens up again across east central CO by mid day. Once again, the timing and exact track of this intensification will play a big role in snowfall amounts. Overall, this storm looks a little weaker than the last as far as upglide and development of the wrap around snow band/trowal. But this system will also be colder with persistent light snow expected to continue through Tuesday as trailing energy moves across. This could lead towards greater travel impacts for the urban corridor of southern Colorado. Overall, snowfall amounts are coming out on the light side of advisory range, so will issue Winter Weather Advisory for the southeast mountains and adjacent I-25 corridor from roughly Walsenburg northward. With some southeast to easterly upslope flow, expect some snow to spread up the Arkansas River Valley of Fremont county and perhaps into southern Chaffee county. Current advisories do not include the Sangre De Cristo mountains as of yet but an earlier storm intensification, or stronger upslope could necessitate upgrades. Northern El Paso county is another area to watch but for now we are keeping higher totals on the southern slopes of the Palmer Divide. A tad farther south track and the southern I-25 corridor down to Raton could also get in on the action, but with less of an upslope component down that way, have left them out for now. Expect some improvement Tuesday afternoon as focus for the heavier snow shifts eastward across the plains. Tuesday will be much colder with persistent cloud cover across southern Colorado. High temperatures will likely stay in the 20s across the lower elevations with teens and single digits across the higher terrain. .LONG TERM...(Tuesday night through Monday) Issued at 250 PM MST Mon Jan 25 2021 Tuesday night... The major shortwave with very cold air associated with it will be exiting the CWA with only a few lingering snow showers over the highest elevations of all mountain ranges. Some snow will still be possible over the plains as well due to the wrap-around moisture overrunning cold surface temperatures in the deformation zone. All precipitation should completely exit the region by midnight with clearing throughout early Wednesday morning. Wednesday through Friday... High pressure is going to dominate the area once the low pressure system exits the region by early Wednesday morning. Both of the GFS and ECMWF models are picking up on a weak upper level low from the subtropical ridge to the southwest over the Pacific Ocean that will absorb into the ridge and could allow for some higher level precipitous clouds over the region on Friday, while the mid and lower levels remain very dry. Friday night through Sunday... All of the deterministic models are in relative agreement with the timing of the next major shortwave trough to influence the CWA late friday night, except that the ECMWF has this system moving into the region about 3 hours earlier late Friday night. Due to the orientation of this trough, most of the precipitation will be confined to the mountainous areas of the CWA, especially for Saturday morning, where the greatest amounts of snowfall will be located on the southwestern facing slopes of the San Juan Mountains. The low pressure center associated with this trough will propagate quickly out over the Great Plains and not provide much in the way of any snowfall for the plains within the CWA. Sunday night through Tuesday... A ridge will begin to build back in with warmer and drier conditions for a majority of the CWA with only a few snow showers over the Sawatch range due to some troughing to the northwest of the region. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) Issued at 1027 PM MST Mon Jan 25 2021 Upper low pressure system currently over west central AZ will slide across the Four Corners and CO over the next 24 hrs, producing widespread IFR to LIFR conditions due to low clouds, fog and -sn for the area through the forecast period. KPUB and KALS sites report MVFR to VFR conditions currently but this will be short-lived, with conditions quickly degrading by 08z. Moore && .PUB WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 5 PM MST Tuesday for COZ068-074- 075-084-088. Winter Weather Advisory until 8 PM MST Tuesday for COZ076-077- 079>083-085>087. && $$ UPDATE...PETERSEN SHORT TERM...KT LONG TERM...STEWARD AVIATION...MOORE