


Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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013 FXUS65 KGJT 302337 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 537 PM MDT Mon Jun 30 2025 .KEY MESSAGES... - Afternoon showers and storms are expected each day with the best chances on the higher terrain. - Showers will be capable of producing gusty winds upwards of 50 mph, small hail and perhaps localized heavy rain by midweek. - Better moisture moves in midweek increasing the chances for widespread showers and storms. - Unseasonably warm conditions remain in place through mid week. && .SHORT TERM /THROUGH TUESDAY NIGHT/... Issued at 1257 PM MDT Mon Jun 30 2025 Currently there is a ridge of high pressure in place, so temperatures are running 5-10 degrees above normal. The moisture that was in the northern half of the forecast area yesterday has been pushed to the southern half of the area today. Convection has already initiated over the higher terrain, and expect some of that activity to move into the surrounding valleys through sunset. Gusty outflow winds up to 50 mph, small hail, and fire starts will be the main thunderstorm threats. Overnight the southeasterly low level jet ramps up over the Four Corners, which will advect more moisture into the region. There is not much change to the overall pattern tomorrow other than the increased moisture. This should result in a slight uptick in afternoon convection with the highest chances occurring in the southern mountains. The same impacts will be expected from these storms. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... Issued at 1257 PM MDT Mon Jun 30 2025 Low pressure over California and high pressure over the Gulf will keep deeper moisture moving into the CWA thanks to flow around these two features. This is corroborated by forecast NAEFS PWATs indicating values of 2 to 2.5 standard deviations above normal early July values. This moisture will be worked on by a shortwave trough Wednesday afternoon which will allow some widespread showers and thunderstorms to fire. Some heavier rain is very likely under and near the stronger cells. Convection is expected to fire over the higher terrain and then possibly drift into adjacent valleys as the wave moves through. Thursday, the low pressure that was out west will become an open wave and start moving across the CWA. Models continue to indicate Thursday being the day with the most widespread and heaviest precip. Highly anomalous PWATs will remain across the area and the added lift from the open wave will be the impetus for this precip. The only fly in the ointment will be cloud cover that may limit convection. If this occurs, we can expect a more stratiform, soaking type rain event with some embedded storms being more likely. Still have plenty of time to work out these finer details. Model differences appear Friday as the GFS wants to keep heavier rainfall confined to the Divide and adjacent mountains while the EC only keeps a few showers in the picture. Again, plenty of time to hammer out this details. Ridging builds in for the weekend with a return to sunny skies and warming temperatures.&& .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 1126 AM MDT Mon Jun 30 2025 Convection will continue firing over the higher terrain this afternoon with a few showers and thundestorms possible. Central and southern portions of the CWA are favored for this convection. Put PROB30 groups in for KASE and KEGE where chances are highest to see some storms. The biggest concern will remain gusty outflow winds. Convection will die down towards sunset. Even with the showers and storms, VFR will remain in place for the next 24 hours. && .AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 537 PM MDT Mon Jun 30 2025 Some light showers have persisted into this evening over KDRO, KEGE, KTEX, and KGUC. However, these storms are anticipated to dissipate over the next hour. Impacts should be minimal with VFR conditions remaining in place. This evening and into the early portions of tonight, some 20-25 knot gusts are possible at KASE, KMTJ, and KGUC. Tomorrow afternoon, showers and thunderstorms are again expected with storms mostly developing along higher terrain. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...KJS LONG TERM...TGR AVIATION...TGJT