877 FXUS63 KGLD 080821 AFDGLD Area Forecast Discussion National Weather Service Goodland KS 221 AM MDT Fri Oct 8 2021 .SHORT TERM...(This evening through Friday morning) Issued at 306 PM MDT Thu Oct 7 2021 RAP analysis has an upper level low over the upper Midwest with a developing longwave trough just off the California coast as weak ridge is over the central High Plains. The ridging continues the current pattern of dry conditions with little cloud cover. Winds have increased due to daytime mixing as a surface low cross over SW Kansas bringing isolated wind gusts of 20+ knots to locales along and south of Interstate 70. An area of clouds moves through during the overnight hours as winds fall below 10 knots across the area. The area of clouds is anticipated to keep the temperatures in the upper 40s to low 50s despite the light winds. Friday, southerly flow dominates as the trough moves further inland over. Dry conditions continue with elevated fire weather concerns along and west of Highway 27 as RH values fall into the lower teens with winds from the south around 10 knots, with locally higher wind gusts possible through the afternoon. Afternoon high temperatures are forecasted to be in the low to mid 80s across the area. Clouds increase during the late afternoon and evening hours west to east limiting the overnight low temperatures to the low to upper 50s. Saturday, the ridge moves to the east of the area as the above mentioned trough moves closer to the area from the west and an approaching cold front from the northwest. A strong jet through the atmospheric profile will present in part to the trough as strong westerly downslope winds will cause strong surface winds along with warm temperatures. Temperatures for the day will be the tricky part based on the speed of the cold front, behind the cold front afternoon high temperatures look to be in the mid 70s to low 80s. Ahead of the front where the southerly flow coupled with the downslope winds interact will see afternoon high temperatures in the mid 80s to perhaps low 90s in a few locales. A few record highs may be in jeopardy with Hill City currently forecasted at 89 and their record high for the day is 90 set back in 1965. Moving on to the winds, using the NBM 90th Percentile as guidance, am currently expecting sustained SSW winds of 20 knots (perhaps higher) with gusts of 30-35 knots possible throughout the afternoon, some localized areas of blowing dust are also possible. These strong winds coupled with the warm temperatures and the dry conditions will lead to near critical fire weather conditions for locations along and south of Interstate 70 Saturday afternoon. If a fire were to get started it would spread quickly with the strong winds and dry conditions. A Fire Weather Watch was considered for counties south of Interstate 70, but held off for now as RH values continue to show Upper teens to low 20s for the area. As the cold front and trough move through this will bring a slight chance for rain showers Saturday night through Sunday morning. Currently, the best forcing looks to remain just south and west of the CWA but a small wiggle to the north would increase the chances especially along and south of Interstate 70. Overnight lows for Saturday night into Sunday morning are forecasted to be in the low 40s to low 50s with colder temperatures located over eastern Colorado. .LONG TERM...(Monday through Friday) Issued at 220 AM MDT Fri Oct 8 2021 The long term period is generally dry short of the system that will move through the area Tuesday/Wednesday. Temperatures are expected to be near to below average for much of the period. Monday starts out with clear and dry conditions as the Tri-State area sits under small amplitude ridging aloft inbetween the previous trough and the new one forming and moving through the Western CONUS. Temperatures look to reach the mid to upper 70's. Elevated to near critical fire weather conditions may be possible mainly along and west of the Colorado border as winds gust to near 25mph and RH drops to near 20%. Tuesday on gets a bit uncertain due to the next upper trough and system that would be moving in from the west. Guidance currently has the upper trough swinging through the four corners during the day on Tuesday with a surface low taking shape just east of the Front Range. This setup would still have the Tri-State area warm into the mid to upper 70's across much of the area but could see an increase in the winds as the pressure gradient tightens and the flow increases aloft. The dry conditions would then give way to chances for showers and storms during the evening and nighttime hours as the surface low and associated cold front move to the east and moisture gets pulled into the area from the south. As mentioned above there is some uncertainty as guidance has been inconsistent on the placement of the trough and surface low as well as the depth of the trough. Ensemble anomalies show this as well with rather large anomalies in the depth in the trough. There is less anomaly with the location but still enough worth considering for a slower and/or more southerly track. With the winds, precipitation, and temperatures fairly dependent on the track, the current forecasted temps, wind, and precip may change in the coming days. However, looking across the difference solutions, there is a high chance the area would see stronger than average winds, some precipitation, and cooler temperatures as this system passes. Wednesday will depend on how the trough and low move off to the north/northeast as the area could be in the dry slot of the low or be in the region of wrap around moisture. Current forecast mirrors more of the wrap around solution where the temperatures would be cooler in the low to mid 60's and some light rain is present early in the day. But if the dry solution prevails, the daylight hours would see mostly clear skies and temperatures could warm to be near 70 or in the 70's. Thursday and Friday are currently forecasted to have the Central CONUS under a broad trough aloft with the area under northwest flow. While that could give the area some instability, the forecast calls for dry air to move in from the southwest once the prior trough and surface low lift off to the northeast. This will help the area stay dry and mostly clear though temperatures could remain a bit cooler than average depending on how much cooler air moves in behind the front. && .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 936 PM MDT Thu Oct 7 2021 VFR conditions will prevail at KGLD and KMCK through the forecast period. Winds will remain light and variable overnight and through the morning, increasing to around 5-10kts from the southeast in the afternoon. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...TT LONG TERM...KAK AVIATION...AW