


Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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895 FXUS65 KGJT 022101 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 301 PM MDT Tue Sep 2 2025 .KEY MESSAGES... - Temperatures trend about 5 degrees above normal through Wednesday before a cooler and more active storm system moves in by Friday. - More widespread precipitation is possible on Friday and into the weekend as rich extra-tropical moisture moves into the region with a potential for heavier rain on the recent fire scars. && .SHORT TERM /THROUGH WEDNESDAY/... Issued at 259 PM MDT Tue Sep 2 2025 High pressure drives the forecast tomorrow bringing continued warm and dry conditions. High temperatures continue to run around five degrees above normal for early September with isolated afternoon showers and storms over the Divide mountains. Coverage of convection looks to be less than what we`re experiencing this afternoon. Cloud cover increases from the southwest Wednesday night with portions of southeast Utah and southwest Colorado seeing warmer than normal nighttime lows. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... Issued at 259 PM MDT Tue Sep 2 2025 A pattern shift will allow for a return of moisture beginning Thursday afternoon. A trough pushing inland off the Pacific will begin to break down the high pressure centered over the Four Corners region. As it does so, moisture will advect into the region, first in southeastern Utah before becoming widespread over the CWA late this week. On Thursday elevated PoPs are mostly confined to south of I-70, where moisture is most abundant during the afternoon hours. PoPs in this region remain elevated overnight, and less tied to the terrain, as a passing weak wave of energy provides upper-level support while moisture continues moving in. By Friday PWATs will be anomalously high across the whole region, peaking near 150% of normal through Saturday. This means widespread chances for showers and thunderstorms across the CWA over the weekend, even outside of the high terrain. A factor adding uncertainty into the forecast is the impact of a tropical disturbance in the Pacific, which recently became Tropical Storm Lorena. If the remnants of Lorena move into the Southwest, there could be potential for additional moisture advection to occur with the monsoonal push from the pattern change. However, the forecast for this is still uncertain between models, so not much can be said with confidence. Moisture looks to slowly move out of the area towards the end of the long term. Temperatures are expected to cool this weekend with the increase in moisture, dropping highs below normal. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 1142 AM MDT Tue Sep 2 2025 There is a chance of isolated to scattered showers and thunderstorms in the San Juan Mountains this afternoon. As such, PROB30 has been included for KTEX and KDRO. Main concerns with the afternoon convection will be gusty outflow winds and lightning. Otherwise, winds will be light and terrain driven, and VFR conditions are expected to prevail. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...KAA LONG TERM...GF AVIATION...TGJT