Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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443 FXUS65 KGJT 161707 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 1107 AM MDT Thu May 16 2024 .KEY MESSAGES... - Scattered showers and thunderstorms favored over the southern mountains and adjacent valleys today with a few isolated storms possible into the central mountains. Gusty outflows and small hail are the main threats. - Drier and warmer conditions move in tomorrow with temperatures running around 5-10 degrees above normal. - Warm temperature persist through the weekend with isolated afternoon thunderstorms possible...before a general cool down begins for next week as the weather pattern becomes more unsettled. && .SHORT TERM /THROUGH FRIDAY/... Issued at 320 AM MDT Thu May 16 2024 The northern and southern stream systems are finally phasing early this morning. An area of channelized vorticity extends from the trough over the Northern Plains to the upper low moving through the 4 Corners. This area of PV is showing up clearly on H2O imagery and will be dropping through the southern half of the CWA through the day. The bigger impacts will be over the southern mountains and adjacent valleys when this forcing moves through closer to peak heating for scattered shower and thunderstorm development. Gusty outflow winds should continue to be the main threat though a few of the stronger updrafts may be capable of throwing out some small hail. This phasing system is all being kicked eastward by a more robust upstream system that will be arriving to PacNW by this evening...forcing a transitory ridge across our CWA Friday for a warmer and drier forecast across the board. High temperatures today...outside of the stormier south...will be near to slightly above normal and by tomorrow most areas should reach the 5 to 10 degrees above normal mark. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... Issued at 320 AM MDT Thu May 16 2024 The upper level trough, centered over southern Saskatchewan, will continue to push into the Northern Rockies on Friday night, shifting flow aloft across the forecast area to the west. A quick shower or two may develop near the Wyoming border as the base brushes by but, overall, Friday night will remain quiet with just some passing clouds. This system will exit to the northeast for Saturday, making room for yet another trough to dig into the Pacific Northwest during the day. Additionally, a weak circulation hovering off the coast of southern California will gradually lift into the Desert Southwest, kicking off some light isolated to scattered showers and storms over the southern mountains Saturday afternoon. The pattern gets muddled going into the latter half of the weekend as the aforementioned upstream trough pushes farther inland across the Intermountain West, eventually absorbing this weak boundary coming up from the Four Corners. Showers will begin to favor the northern tier of the region for Sunday afternoon but orographics will likely fire off additional convection for our other mountain ranges, or at least plenty of clouds. On Monday troughing aloft becomes more organized, hovering near the Canadian border as it dominates the western CONUS. Southwest flow will become more pronounced by Monday morning before it continues to strengthen into Monday night. Still quite a bit to work out as far as available moisture goes but, with this tightening gradient, breezy conditions can be expected at the surface Monday afternoon. There will be clouds and some showers to contend with so just how windy remains to be seen. The main trough axis lifts overhead before the midweek point with active weather looking to prevail going into late May. Unseasonably warm temperatures will dominate the weekend under mild southwest flow. Afternoon highs will remain 6 to 12 degrees above normal both Saturday and Sunday before values drop to just a few degrees above normal for much of the region on Monday. If the trough remains on track and pushes through early next week, Tuesday`s highs will be below normal area-wide. Overnight lows through the long term period will generally be on the mild side. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 1107 AM MDT Thu May 16 2024 VFR conditions under mid to high cloudiness is expected over the next 24 hours. A few showers and storms are possible over SW Colorado this afternoon but coverage will be limited enough to keep VC in the TAF forecast for now. Gusty winds remain the main threat near storms. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...15 LONG TERM...MMS AVIATION...TGJT