Area Forecast Discussion
Issued by NWS Grand Junction, CO

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177 FXUS65 KGJT 161134 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 534 AM MDT Sun Jun 16 2024 .KEY MESSAGES... - Gusty southwest winds, single digit relative humidities, and warm temperatures today and Monday. Red Flag Warnings are in effect both days. - A frontal passage Monday night will bring cooler conditions Tuesday and Wednesday. Light cloud cover and no precipitation is expected with this front. - Unsettled conditions return Thursday, with afternoon convection expected through the extended period. && .SHORT TERM /THROUGH MONDAY/... Issued at 334 AM MDT Sun Jun 16 2024 A trailing frontal boundary dragging behind a Saskatchewan low is pulling some weak Pacific moisture across the northern portion of the Great Basin and to our north along the Wyoming state line this morning. These are the only clouds showing up on satellite here in the CWA this morning. The inverted v sounding at Grand Junction last night sums up the very dry surface conditions well. This trend will continue today and tomorrow as the upper level flow pretty much holds steady at a southwesterly reach for the next 36 hours. Single digit relative humidities, gusty winds, and temperatures well above climatological averages can be expected today and Monday ahead of the aforementioned frontal boundary that swings through in the extended term(more on that below). Meanwhile, winds will ratchet up this afternoon out of the southwest with gusts 30 to 40 mph and steady winds of 20-30 mph. Winds south of the Colorado River will be a touch lighter, but still high enough to warrant our Red Flag Warnings. Winds will temper towards sunset and relative humidities are expected to recover back above Red Flag thresholds by around 10pm MDT. Monday will pretty much rinse and repeat today. However, winds will strengthen in the tightening gradient ahead of the front. Our northern counties can expect gusts closer to 45 mph Monday afternoon, as well as a few invading mid/high level clouds along the front. Have held off on a Wind Advisory Monday afternoon with coverage in question, but the northern zones of the CWA are expected to be close as the front approaches. Surface conditions remain extremely dry and Red Flag Warnings are in place for Monday as well for the zones included in today`s product. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... Issued at 334 AM MDT Sun Jun 16 2024 Winds finally subside as the system and upper level support responsible shift to our east and a dry, cold front moves across the area. By Tuesday morning, the front will have moved across the entire CWA bringing cooler temps to the region. High temps will be 10 to 15 degrees cooler from the central valleys northward and 5 to 10 degrees cooler farther south. Tuesday and Wednesday will be pleasant but the rest of the long term period gets interesting. A broad trough will set up across the western US while a large area of high pressure sets up along the East Coast. The location of the high will tap into deep tropical moisture and anti-cyclonic flow will cause this moisture from the Gulf of Mexico to move northwestward across Texas and eventually move into our CWA allowing an uptick in convection Thursday onwards. Some subtle minor disturbances will move through UT and CO during this timeframe and will work on this moisture allowing said convection to fire. This chance for convection will fire each afternoon and evening through Saturday. As of now, the widest coverage looks to occur on Thursday and Friday but some isolated to scattered convection will continue into the weekend. Forecast dewpoints and RH values are forecast to increase during this timeframe so the chance for some wetting rains looks promising. Clouds and precip will also temper high temperatures as well as convection so we`ll have to see how this all plays out. For now, the NBM has a 40 to 60% chance PoPs for mainly the southern half of the CWA as well as along the Divide for both Thursday and Friday but we`ll see how things end up once the short range models get involved. Enjoy Tuesday and Wednesday as unsettled weather returns after that. && .AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
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Issued at 531 AM MDT Sun Jun 16 2024 VFR conditions will continue through the TAF period. A few high clouds will invade late in the period from the northwest. Strong southwesterly winds will produce gusts of 30 to 40 mph across much of the region with the strongest winds favoring northeast UT and northwest CO.
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&& .FIRE WEATHER... Issued at 334 AM MDT Sun Jun 16 2024 Red Flag Warnings are in place for southeast Utah, southwest Colorado, and west-central Colorado today and tomorrow. Strong southwest winds gusting 30-40 mph, single digit relative humidities, and well above normal temperatures will keep critical fire weather conditions locked in. RH values will recover during the overnight hours and winds are expected to subside some as well. A frontal passage on Monday night is expected to return fire weather conditions to subcritical on Tuesday. Wetting rains are not expected. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...Red Flag Warning from 11 AM this morning to 10 PM MDT this evening for COZ203-207-290>293. Red Flag Warning from 11 AM to 10 PM MDT Monday for COZ203-207- 290>293. UT...Red Flag Warning from 11 AM this morning to 10 PM MDT this evening for UTZ490-491. Red Flag Warning from 11 AM to 10 PM MDT Monday for UTZ490-491. && $$ SHORT TERM...LTB LONG TERM...TGR AVIATION...TGJT FIRE WEATHER...TGJT