Area Forecast Discussion
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
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661 FXUS65 KGJT 021110 AFDGJT Area Forecast Discussion National Weather Service Grand Junction CO 510 AM MDT Thu May 2 2024 .KEY MESSAGES... - Cooler temperatures expected today in the wake of the cold front that brought a few showers and passed through yesterday. - A disturbance will brush the northern tier of eastern Utah and western Colorado on Friday, bringing a few valley rain and mountain snow showers along with it. - Warmer and mainly dry conditions return on Saturday before turning windy on Sunday and more unsettled early next week. && .SHORT TERM /THROUGH FRIDAY/... Issued at 200 AM MDT Thu May 2 2024 Yesterday`s and last night`s showers, which were associated with a passing cold front, have either diminished or moved east and out of the area as of early this morning. In the wake of the front, much drier air is currently working in from the west, as evidenced by dew points in the single digits and teens. Satellite imagery shows a few clouds lingering along the central and southern Continental Divide mountains, but expecting these to largely dissipate by sunrise. The mainly clear skies, very dry air, and light winds will result in ideal radiational cooling conditions this morning, which suggests a chilly start as you`re walking out the door. Additionally, it`s not completely out of the realm of possibility for some patchy frost to develop in the typically colder spots across the CWA. Those with agricultural interests may want to keep an eye on those temperatures. Otherwise, we`re looking at a lot of sunshine this morning before clouds start to increase across the northern tier of eastern Utah and western Colorado this afternoon. Those clouds are in response to a weak wave that will brush along the Colorado / Wyoming border. Given the aforementioned dry air moving in, not expecting anything in the way of precipitation today, other than maybe a sprinkle way up high. The chilly start, the increasing afternoon clouds, and the post-frontal air mass will keep temperatures near or even slightly below normal for this time of year. After a quiet and seasonably cool night tonight, attention then turns to a stronger wave that will again trek across the border of Colorado and Wyoming on Friday. Despite having a fair amount forcing both aloft and along a surface cold front, the dry air still in place will keep almost everywhere dry except portions of northeast Utah, northwest Colorado, and the northern Colorado mountains from late morning into the afternoon and evening. Even in those areas, the highest precipitation totals will mainly be confined to the higher elevations with a tenth up to a quarter of an inch of QPF expected... maybe a bit more in the Park Mountains. It will still be cold enough for snow up there above 7000 to 8000 feet, so some light accumulations are a decent bet. Given the time of year, however, little to no impacts are anticipated. The cold front will bring cooler air in across the north on Friday, but will have a tough time making it much farther south than the I-70 corridor before washing out. Thus, little change in temperature is expected across much of southeast Utah and southwest Colorado. In fact, the washed out cold front will return northward as a warm front Friday night into Saturday, bringing much warmer temperatures to start off the weekend. More on that in the long term discussion below. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... Issued at 200 AM MDT Thu May 2 2024 On Saturday, the low to the west moves ashore over southern Oregon causing the area to fall under broad difluent southwest flow aloft. Meanwhile, strengthening southwesterlies will drive the cold front northward and out of the forecast area with much warmer air filtering into the region during the day. Lingering moisture is expected to yield isolated to scattered showers and thunderstorms over the mountains of the Continental Divide Saturday afternoon while the remainder of the region remains dry and warmer with highs climbing to around 10 degrees above normal. From Saturday night to Sunday the closed low moves over the Great Basin. Pre-frontal height packing ahead of the impressive cold front associated with this system will result in windy conditions from late morning Sunday into the early evening. Pre- frontal wind gusts could be as strong as 50-60 mph. Virga showers with the arrival of midlevel moisture will only increase the potential for these gusts. Moisture arrives over northeast Utah early with showers becoming likely for the eastern Uinta Mountains during the afternoon with more scattered activity north of the I-70 corridor and far northwest Colorado. The models including operational and ensemble are in decent agreement with the system timing, track and strength. The center of the low pressure looks to pass just to our northwest late Sunday and lift out over the Plains on Monday. This will be the most active period of this storm. Snow levels at the onset will be around 10 kft, but drop to 6 kft by Monday morning due to the cold front and lower heights. The northern and central mountains have the best shot at accumulating snowfall with perhaps advisory amounts in the northern ranges. A secondary wave trough sweeps over the area Monday night into Tuesday and as a result, the chance for showers over the northern mountains will continue. && .AVIATION /12Z TAFS THROUGH 12Z FRIDAY/... Issued at 510 AM MDT Thu May 2 2024 Skies have cleared across eastern Utah and western Colorado with the exception of some high clouds streaming in from the northwest. High and mid level clouds will become more prevalent across the north this afternoon as a weak disturbance brushes past the Colorado/Wyoming border. Ceilings should mostly stay above ILS breakpoints. South of the I-70 corridor, mostly sunny skies will prevail today. Winds will become a bit breezy this afternoon with gusts of 25 to 35 mph common, especially in the higher elevations. Winds become light and terrain driven shortly after sunset with quiet weather to follow overnight. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...None. UT...None. && $$ SHORT TERM...MDM LONG TERM...KJS AVIATION...MDM