Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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900 FXUS65 KGJT 241735 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 1135 AM MDT Fri May 24 2024 .KEY MESSAGES... - Chances for showers and storms increase later today and continue through tomorrow. Gusty winds will be possible with these showers and storms. - Mountain snow is possible generally above 9 kft with the impacts to the roads occurring tonight and tomorrow night. Highest chances and amounts will be in the northern and central mountains. - Temperatures will run below normal through the weekend then increase next week. Precipitation chances remain low through mid week. && .SHORT TERM /THROUGH SATURDAY/... Issued at 139 AM MDT Fri May 24 2024 A trough will drop into the Great Basin later today allowing for southwest flow aloft over our region. Modest moisture will advect into the area in the form of clouds and eventually showers beginning this afternoon. The low levels are rather dry and so initially showers will have trouble reaching the ground. Winds are not expected to be as high as yesterday in general, but any virga could enhance gusts. The better moisture will spread over the northern half of the forecast so that is where the chances are for showers. Precip chances and coverage increase tonight as the trough approaches from the west, again mainly north of I-70. High temps today will range from 10 degrees below average up north to near normal down south. Tomorrow, the base of the trough passes over the area with the focus for lift across the north. This will be the best timeframe for precip. Showers may expand south of I-70 during the afternoon due to the trough progressing eastward. It appears that minor QPF is possible in the San Juans with none along the New Mexico state line. There are indications that mountain snow is possible with this system. The northern mountains may end up with several inches generally above 9-10 kft. Instability will be present in the prefrontal airmass tomorrow so expect thunderstorms. Winds increase in general due to a tighter pressure gradient. Any strong convection will have the chance to produce gusty winds perhaps upwards of 50 mph. High temperatures will end up similar to today. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 139 AM MDT Fri May 24 2024 The upper level trough will be just about directly over the CWA Saturday night with models placing the heaviest precip along the surface cold front. This band of precip looks to set up from the northern mountains down through the Flat Tops to near Douglas Pass in the Book Cliffs. As the night progresses, the front will continue to drop south and east bringing some rain/snow to the central mountains by late evening, the same for the San Juans by midnight. This is a quick moving system and by daybreak Sunday morning, the trough will be over the Front Range with all precip having ended. When all is said done, 2 to 4 inches of snow above 10K feet will be the end result with 0.2 to 0.4 inches of QPF...some locally higher amounts expected for both snow and rain. Previous model runs showed a second system moving through on Sunday but all guidance is now indicating stronger ridging building into the Intermountain West which will keep that second system much further north. We`ll see mostly sunny skies out west with partly cloudy skies along the Divide and higher terrain, lifting through the day. Ridging builds in Monday onwards and ushers in warmer temperatures with some of the warmest temperatures seen so far this year for Wednesday and Thursday. Under the ridging, we`ll see the usual afternoon breezes and partly cloudy skies. Slight chance for some convection firing along the Divide each afternoon but coverage and chances are low (10 to 30%). A more pronounced trough passes through Wednesday evening but with limited moisture, not expecting much, if any, sensible weather. Wouldn`t be surprised if this changes as we get closer to the event. Time will tell. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1124 AM MDT Fri May 24 2024 Expect VFR conditions with increasing clouds ahead of the next system through the next 24 hours. Look for isolated to scattered showers to move in from the northwest overnight becoming scattered along and north of the I-70 corridor after about 15Z. Included vicinity showers from KCNY and KASE northward late in the TAF period with showers becoming predominant at KVEL after 16Z. Conditions will remain above ILS breakpoints through the TAF period. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...KJS LONG TERM...TGR AVIATION...DB