


Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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877 FXUS65 KGJT 051726 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 1126 AM MDT Sat Jul 5 2025 .KEY MESSAGES... - Near-normal temperatures today will climb to 5-10 degrees above normal by Wednesday, remaining above normal for the rest of the week. - High pressure will usher in a much drier period, although a slight chance of daily showers or storms remains along the Divide. && .SHORT TERM /THROUGH SUNDAY/... Issued at 240 AM MDT Sat Jul 5 2025 Moisture is starting to come down across the region as drier air advects in from the southwest. However, as of last night`s 00z sounding, PWAT values are still right around the 90th percentile for that day, indicating there`s still quite a bit of surface based moisture up for grabs along and north of I-70. And that moisture has been, in concert with a passing wave, a line of showers and thunderstorms tracking across northeast Utah and northwest Colorado. This area of showers and storms should track north and east of the region by daybreak, with clear skies dominating behind it. High pressure will dominate today, with strong subsidence really limiting any afternoon convection that could develop. Additionally, deep mixing under the strong daytime heating will continue to mix down that much drier air aloft, scouring out the surface based moisture. The best chance to see a shower or thunderstorm will be along the Divide, but even that is a less than 10% chance. Temperatures rebound to near-normal values today, with highs in the mid to upper 90s across the desert valleys and highs in the 70s for the mountain towns. High pressure remains with us tomorrow, promising mostly clear skies and temperatures climbing to 3-5 degrees above normal. Some moisture tries to sneak in from the south, increasing the chances of isolated showers and thunderstorms along the southern and central Divide mountains during the afternoon. The main threats with this activity will be gusty outflow winds, frequent lightning, and small hail. Any showers that do form will taper off after sunset, with a quiet, seasonal night on tap. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... Issued at 240 AM MDT Sat Jul 5 2025 A center of high pressure to our south will set up our region for a series of hot and dry days, with chances for precipitation over the terrain each afternoon. Despite elevated PoPs over the Divide and San Juans each day of the long term, the actual quantitative amount of precipitation in the forecast is very little. The GFS Ens has been trending drier, finding agreement with the ECMWF Ens. Although, the ECMWF Ens is still forecasting less moisture available than the GFS Ens. Overall PWAT anomalies look to be 70-100% of normal through the end of the workweek. With these dry conditions in place, showers and thunderstorms over the terrain are generally not expected to be efficient producers of rain that reaches the ground. Single digit afternoon relative humidity values return to the forecast through the long term. Despite the anticipated dry conditions, calm winds from high pressure should keep us from meeting critical fire weather conditions. However, a closed low off the coast of California looks to make its way across the West through the week, passing to the north of our CWA on Thursday as a weak trough. As the pressure gradient increases with the passing trough, there is potential for stronger afternoon gusts. High temperatures will be above normal, with Wednesday looking to be the hottest day. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 1125 AM MDT Sat Jul 5 2025 Mostly clear skies are in place across the region. Winds are calm as of now, but are expected to become breezy this afternoon. Gusts of 18-24 kts are possible. VFR conditions will prevail throughout the next 24 hours. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...BGB LONG TERM...GF AVIATION...TGJT