Area Forecast Discussion
Issued by NWS Goodland, KS
Issued by NWS Goodland, KS
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299 FXUS63 KGLD 181712 AFDGLD Area Forecast Discussion National Weather Service Goodland KS 1112 AM MDT Wed Sep 18 2024 .KEY MESSAGES... - Critical fire weather conditions are possible over portions of the area on Friday, mainly along/west of Hwy 25 where breezy southwest winds may develop during the mid-late afternoon. - Showers and thunderstorms will develop over much, or all, of the Tri-State area this weekend as a potent upper level low tracks eastward across the Rockies and Central Plains. Severe thunderstorms, heavy rainfall and isolated flash flooding are possible, mainly Saturday afternoon through Sunday morning. && .SHORT TERM /THROUGH FRIDAY NIGHT/... Issued at 400 AM MDT Wed Sep 18 2024 Overview: A modest upper level ridge over the Southern Plains will amplify and extend northward over the Central Plains through the remainder of the work week. Meanwhile, a potent upper level low.. presently situated offshore the Oregon coast.. will dig S-SSE along the CA coast (today-tonight), stall invof central-southern CA (Thu-Thu night), then track E-ENE toward the 4-Corners (Fri-Fri night). Today-Tonight: Subsidence in the wake of a progressive shortwave (lifting northeastward into central Nebraska at 09Z this morning) will foster a west-east clearing trend this morning. Expect sunny skies, dry conditions and above-average temps this afternoon (albeit several degrees cooler than yesterday). While light S-SW or variable winds may prevail in eastern CO (invof a weak, broad lee trough).. forecast soundings suggest that downward momentum transport assoc/w deep vertical mixing may yield 15-25 mph SW winds over much of northwest KS and southwest NE this afternoon. Thursday: Clear skies and unimpeded insolation assoc/w the amplifying upper ridge over the region will foster dry conditions and above average temperatures, though.. a short period of breezy (15-20 mph) N winds and modest cold advection (assoc/w the passage of a weak surface to 850 mb /SFC-H85/ trough Thursday morning) may temper highs to some degree. Expect light/variable winds and temperatures ranging from ~80-90F during the afternoon, coolest in northeast CO. Friday: Upper level flow will back to the SW and strengthen late Fri-Fri night.. as the aforementioned upper low progresses east toward the 4-Corners. Forecast soundings continue to suggest that deep vertical mixing and strengthening mid-level flow may yield breezy (20-35 mph) SW winds and exceptionally dry conditions over portions of the area late Fri afternoon.. mainly along/west of Highway 25, where critical fire weather conditions are possible. Isolated high-based convection cannot entirely be ruled south of I-70 during the late afternoon, when and where marginal high-based instability (~100-250 J/kg MLCAPE) may be present invof a modest low-level convergence zone / dryline. At present, guidance suggests that diurnal convection will be relegated south and east of the Goodland CWA. Outflow /mesohigh development/ emanating from upstream convection.. in this case, southeast CO and southwest KS would be `upstream`.. could (potentially) affect wind/temps in southern portions of the area Friday afternoon.. depending on upstream convective coverage. && .LONG TERM /SATURDAY THROUGH TUESDAY/... Issued at 201 AM MDT Wed Sep 18 2024 The long-term looks to start off active and become more docile through early next week. Saturday morning, a well organized low pressure system will be near the Four Corners Region and rapidly moving northeast into the High Plains. Throughout Friday night, a moderately strong 850 mb LLJ will set up and move additional moisture into the region. The additional moisture will keep temperatures from cooling off too much Saturday morning, but will limit day time heating. High temperatures are expected to be in the upper 70s to low 80s across the region, but if the clouds break, expect warmer temperatures. The combination of warm, moist air with the low pressure system (and associated fronts) will fire off storms, likely in the afternoon and evening hours. Models are fairly consistent will widespread precipitation being expected. Deep layer shear during this event looks to increase the potential for severe weather (~5-10%), but instability is marginal. There is also a small (<10%) chance winds ahead of the storms could gust around 30-35 kts in eastern Colorado producing blowing dust. If there is a clearing of the clouds and the winds are able to pick up, localized blowing dust could occur, otherwise blowing dust is not expected to be a major hazard. As the low moves farther into the CWA, winds will become northwesterly and start cooling off the area. High temperatures on Sunday look to remain largely in the upper 60s, and potentially cooler depending on the efficiency of the CAA. The low pressure system will take until Sunday night to move out of the area, giving the area increased PoPs through Sunday evening. Once the low moves out, northwesterly flow is expected to dominate the High Plains through the remainder of the period. This will keep high temperatures in the mid 70s and lows in the 40s to low 50s for the rest of the period. As is typical in northwesterly flow on the High Plains, shortwaves are bound to occur and could bring isolated to scattered showers and storms into the area. Monday through Wednesday, no organized systems seem likely, just the potential shortwave showers. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1110 AM MDT Wed Sep 18 2024 Low clouds will persist for another hour or two at KMCK, then clearing. Otherwise, VFR expected to prevail at both KMCK and KGLD through the TAF period. Expect a wind shift to the north at both terminals Thursday morning with a cold front. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...None. CO...None. NE...None. && $$ SHORT TERM...Vincent LONG TERM...CA AVIATION...024