Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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245 FXUS65 KGJT 200459 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 959 PM MST Wed Nov 19 2025 .KEY MESSAGES... - 4 to 8 inches of snow across the San Juans is expected through Friday morning, with locally higher amounts. - Snow will spread across the Central and Northern mountains Thursday afternoon with widespread accumulations of 3 to 6 inches by Friday evening. - Temperatures hover around normal through the period. && .SHORT TERM /THROUGH FRIDAY/... Issued at 321 PM MST Wed Nov 19 2025 A deep fetch of moisture continues to stream into the Southwest this afternoon ahead of an open wave moving through the Great Basin. Widespread convection across AZ tells me we`ve put some of the drier conditions away for the time being. Moisture on the Grand Junction sounding this morning held steady, along with stacked southwesterly flow up the column. PWAT values will continue to rise upward this evening and tomorrow across the region. A broad area of cutoff cyclonic flow over the Great Basin continues to send a series of waves across the region through Friday, keeping a persistent moisture tap in place into Friday morning. Generous upslope flow this evening ahead of the first wave will bring some light snow to the mountains of southwest Colorado and southeast Utah, primarily above 9000 feet tonight. Snow levels work downward by Thursday morning, but struggle to get below 8000 feet in the warm air mass. Kept our Winter Weather Advisory starting at 11pm tonight, as we will start seeing some of the best snowfall on the San Juans by daybreak. Travelers in the 550 and 145 corridors will want to take note of the winter conditions on the passes tonight and tomorrow morning. While not in the Winter Weather Advisory, Dallas Divide will see wintry conditions Thursday afternoon into Friday morning. Shortwaves will continue to pinwheel around the main circulation Thursday, spreading additional snowfall northward over the Grand Mesa, Central Mountains, and up to the Flat Tops and Park Range. The richest snowfall will remain around 10,000 feet, as the cutoff flow struggles to entrain any appreciable cold air into this system. North of the San Juans, snow totals hover around 3-6 inches across most of our major mountain groups. Held off on any additional advisories, as coverage of advisory level snow just wasn`t there. High pressure begins to nose into the Northwest on Friday, thereby pinching another cutoff low over Baja California. Drier, subsident flow will curb snowfall on the San Juans early Friday morning, allowing for the winter weather advisory to end. Remnant moisture and orographics will keep some light snow falling across the remainder of our mountains on Friday. Light snowfall rates will keep accumulations in check, but the lion`s share of this storm in our Central and Northern Mountains will fall Thursday evening into Friday morning. Travel impacts on Vail Pass are likely Friday morning. Snow tapers quickly by Friday evening. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... Issued at 321 PM MST Wed Nov 19 2025 A deep closed low will drop into SoCal and the northern Baja by Friday night and separate from the main upper level trough, leaving a deformation (col) area overhead across our CWA. We will still see some lingering shower activity mainly across the northern and central mountains but rates should lessen considerably with subsidence overhead. Saturday is expected to be a relatively quiet day in terms of weather underneath this area of deformation as the closed low tracks into Arizona. Models begin to differ beyond Saturday and are struggling to resolve the details of the timing and track of this low. It`s the track that will make all the difference in how much precipitation we see if any. Confidence in timing and coverage is low as there are discrepancies between models and run to run inconsistencies. The blended guidance at this time tends to favor a more southerly solution, leaning towards the GFS which favors southwest Colorado for precipitation Saturday night through Sunday night with San Juan mountains favored for better snowfall accumulations. At this time, forecasted snowfall amounts are meager but this could very well be due to the inconsistency and uncertainty as yesterday, the models were showing this system completely missing us. If a more northerly track is taken like the ECMWF is indicating, this would result in more widespread precipitation coverage and better mountain snowfall accumulations with precip lingering through Monday. Would like to see better consistency before discussing details regarding forecasted mountain snowfall and impact potential. Temperatures through the period will be near to slightly above seasonable but of course the temperature forecast is all dependent on the track of the low and resultant cloud and precipitation coverage. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 957 PM MST Wed Nov 19 2025 Showers and low to mid level clouds will persist through the period. A round of rain and snow showers will impact terminals along and south of I-70 over the next 3-6 hours, with reinforcing rounds of rain arriving from the south. These showers will work their way north after 12z, impacting KVEL and KHDN by that point. KASE, KRIL, and KEGE will spend much of the next 24 hours at or below ILS breakpoints, and low ceilings will allow for other terminals to reach breakpoints as well. VFR conditions will prevail, but periods of MVFR to IFR will be possible, particularly for KASE and KTEX. Winds will be generally light and variable. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...Winter Weather Advisory until 11 PM MST Thursday for COZ019. UT...None. && $$ SHORT TERM...LTB LONG TERM...MDA AVIATION...TGJT