


Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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711 FXUS65 KGJT 152107 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 307 PM MDT Tue Jul 15 2025 .KEY MESSAGES... - Above-normal temperatures remain status quo through the seven- day forecast though a slight downward trend is expected after midweek. - Gusty outflow winds, lightning, and storms with little rainfall remain threats through midweek. - The trend for increased moisture by the end of the week continues to boost confidence that storms will transition from dry to wet. Storm coverage should increase as a result of the moisture as well from late week into the weekend. && .SHORT TERM /THROUGH WEDNESDAY NIGHT/... Issued at 242 PM MDT Tue Jul 15 2025 Isolated showers and thunderstorms are ongoing across the region. Traffic cameras show that some precipitation is actually making it to the ground, but considering how dry our lower atmosphere is, virga is still anticipated with many of the showers and storms. As a result, the main concerns with thunderstorms are gusty outflow winds and lightning. Small hail is also possible, particularly with the stronger storms near our southern mountains. CAMs show most storm activity ending after sunset, but lingering showers may persist into the overnight hours. Tomorrow moisture advection will increase shower and storm coverage across the region, and increase chances of precipitation making it to the ground. With moisture moving in dryness should subside a bit over the coming days, but today and tomorrow afternoon relative humidity values will still drop below 15% in many areas, particularly in desert valleys. As a result, localized Red Flag conditions are possible through the short term where gusts exceed critical fire weather thresholds. High temperatures will remain above average, but tomorrows highs are expected to be a few degrees cooler than today. && .LONG TERM /THURSDAY THROUGH MONDAY/... Issued at 242 PM MDT Tue Jul 15 2025 On Thursday, the high pressure begins to migrate towards the Southern Plains allowing for southerly flow over us. This should advect better moisture into the area so expect another round of afternoon convection with the highest chances across the south. On Friday and Saturday a weak low pressure moving northward over the Baja may help to enhance the southerly flow and moisture advection. Therefore the coverage of showers and storms looks to increase across the area. The potential for moderate to heavy rainfall looks to increase during this period as well as PWAT values approach 0.75- 1.0 in, 700 mb mixing ratios around 7 k/kg and dew points above 40 F. One factor working against heavy rain for the lower valleys is the warm conditions supporting sub-cloud evaporation. Although it is not out of the question given the moisture. The higher terrain may end up being primed for heavy rain, rock slides and debris flows. Eventually perhaps late in the weekend the northern jet stream sinks southward causing drier air to filter in from the west. This could change the afternoon convection coverage and intensity. With increasing moisture and cloud cover, high temperatures begin a steady decline towards more seasonable temperatures by the time the weekend arrives. However, this will also prevent overnight lows from cooling off as much. Lows are projected to be 5-10 degrees above normal through much of the extended forecast. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1132 AM MDT Tue Jul 15 2025 Showers and storms are possible this afternoon and evening. The main impact will be wind gusts of 30-50 mph mainly in the late afternoon into the evening. Otherwise VFR conditions are expected through the period. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...GF LONG TERM...KJS AVIATION...DB