


Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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974 FXUS65 KGJT 291718 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 1118 AM MDT Sun Jun 29 2025 .KEY MESSAGES... - Mountain storms develop each afternoon with coverage increasing throughout the week ahead. - Unseasonably warm conditions remain in place through mid week. && .SHORT TERM /THROUGH TONIGHT/... Issued at 333 AM MDT Sun Jun 29 2025 Isolated to scattered storms return to the high terrain this afternoon, especially along and north of I-70. While the atmosphere is still rather dry with high pressure building in, enough moisture is progged to be present to produce convection. With the dry near-surface layer remaining in place, gusty outflow winds up to 50 mph and fire starts are the primary thunderstorm threats today. Wetting rains are not anticipated (<20% chance). Temperatures remain unseasonably warm area wide with afternoon highs 5 to 10 degrees above normal for late June. && .LONG TERM /MONDAY THROUGH SATURDAY/... Issued at 157 PM MDT Sat Jun 28 2025 High pressure will still be overhead Monday as a deep area of low pressure spins off the California Coast. Models have been fairly consistent in this regard. During the day Monday, PWATs slowly increase across the area and with this increased moisture, chances (30 to 40%) also increase for a few showers or storms to form, mainly along the Continental Divide. The low pressure will drift eastward some on Tuesday, just enough to start advecting some deeper moisture into the region under broad southwesterly flow. PWATs by Tuesday afternoon/evening will reach anywhere from 150 to 170% of normal early July values. As of now, the best chances (still 30 to 40%) exist over the San Juans for showers and storms. By Wednesday, the low opens up and becomes an upper level trough. Minor pieces of energy will also be rotating up from the south. PWATs Wednesday afternoon will reach 200% of normal and as these 2 features interact with the moisture, an increase in showers and storms is anticipated. The deterministic GFS and EC are on board with this scenario while the NBM is still not as aggressive. Not surprised as there is still plenty of time to nail down the specifics. That being said, the trough pushes through on Thursday bringing another round of precipitation to the eastern UT and the Western Slope. PWATs remain well above normal at 200% but it appears the deepest moisture may shift to the central and northern portions of the CWA. A rather weak, transitory ridge then builds in for Friday and Saturday. Some lingering moisture will allow some convection to fire in the afternoon and evening and we`ll be back to the Divide for favored locations. As mentioned, some discrepancies remain with this forecast but confidence does continue to increase for a period of unsettled weather for midweek. Temperatures through Tuesday will remain above normal and then drop to near normal Wednesday onwards thanks to increased cloud cover and precipitation. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 1116 AM MDT Sun Jun 29 2025 Isolated to scattered showers are expected this afternoon at and around some of the sites. Wind gusts of 30-50 mph are possible with these showers. Otherwise VFR conditions are expected. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...KAA LONG TERM...TGR AVIATION...TGJT