FXUS65 KGJT 092029 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 229 PM MDT Fri May 9 2025 .KEY MESSAGES... - Showers and thunderstorms capable of producing gusty outflow winds and moderate rainfall rates will develop over the higher terrain daily. - Unseasonably warm temperatures remain in place through the weekend into early next week. && .SHORT TERM /THROUGH SATURDAY NIGHT/... Issued at 214 PM MDT Fri May 9 2025 High pressure has become established over the Desert Southwest with the axis extending northward over our region. This has contributed to the warm up with temperatures 5-10 degrees above normal. Moisture remains trapped under the ridge, which has resulted in orographic showers and storms. Gusty outflow winds upwards of 35-45 mph will be possible with these showers. Expect the showers to dissipate around sunset with some clouds lingering overnight. Tomorrow the ridge slides eastward as a trough moves into the Pacific Northwest. Once again, there should be enough moisture for orographic convection in the afternoon. Highs will be fairly similar as today. && .LONG TERM /SUNDAY THROUGH THURSDAY/... Issued at 214 PM MDT Fri May 9 2025 Ridging will remain over our area through the middle of next week. As a result, there are no widespread precipitation events expected through the long term forecast period. That being said, PoPs are elevated in the higher terrain each afternoon as lingering moisture and daytime heating support convection. PWAT anomalies fluctuate around 150% of normal through Monday before dropping below normal on Tuesday. On Monday night a trough will move inland off the Pacific, and will approach our CWA by midweek. Confidence is low on the details of this passing trough, as some guidance suggests impacts will primarily stay to our north. Presently, any precipitation from this system looks like it may fall in the northern half our CWA. High temperatures remain well above normal through Monday while warm air advection occurs with ridging aloft. Monday looks to be the warmest day, with highs 10 to 15 degrees above normal possible in the northern half of the CWA, and 5 to 10 degrees above normal in the southern half of the CWA. By Wednesday high temperatures will fall to below normal as cooler air moves in with the approaching trough. Gusty afternoon winds are expected each day through midweek as the incoming trough brings an increased pressure gradient and strong winds aloft. The strongest afternoon gusts will occur on Monday and Tuesday. These strong winds coincide with low minimum relative humidity values, which could create elevated to critical fire weather conditions on Monday and Tuesday where fuels are deemed critical. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1141 AM MDT Fri May 9 2025 VFR conditions are expected through the TAF period. Isolated to scattered showers and thunderstorms are possible this afternoon over the higher terrain. Gusty outflow winds are possible around showers and thunderstorms. Skies will clear overnight. && .HYDROLOGY... Issued at 221 PM MDT Thu May 8 2025 Warm temperatures and potential for rain-on-snow at mid to high elevations (8500' to 10000') increase the risk of areal flooding and elevated streamflows due to rapid snowmelt. Forecast temperatures extending through the weekend are expected to exceed 5 to 15 degrees above normal for early May, such that highs range in the 60's to 70's across mid to high elevations. In addition, isolated to scattered afternoon showers and thunderstorms are possible over higher terrain along the Divide each afternoon, with precipitation potentially falling as rain as high as 10,000'. Streams and tributaries across the San Juan's and along the Continental Divide over central Colorado are most susceptible to see the effects of warming and potential rain-on-snow accelerating snowmelt and elevating flows. As a result, low-lying areas and valley floors across said terrain could see some minor inundation from snowmelt. Stay away from fast moving water, exercise caution near riverbanks and stay alert to watches and warnings from the National Weather Service. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...KJS LONG TERM...GF AVIATION...TGJT HYDROLOGY...ERW