####018002234#### FXUS66 KSTO 062110 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 110 PM PST Sat Dec 6 2025 .KEY MESSAGES... - Periods of low clouds, mist, or fog continue in the Central Valley for the next few mornings - Seasonable temperatures and light winds are forecast over the next several days && .DISCUSSION... ...Today - Sunday... Stratus/Low clouds were more of the story this morning vs. fog dominating the forecast yesterday but still impacting much of the Central Valley and adjacent lower foothills. Out forecast remains on repeat with another round of low clouds/fog tonight into tomorrow morning with best chances Sacramento northward although fog is possible throughout all of the Valley. Dry weather and seasonable temperatures are forecasted for the region, with upper 40s to 50s in the Valley and foothills, and 40s to 60s in the mountains for the daytime highs. Highs are trending several degrees cooler than initially forecasted due to the persistence of the fog/low clouds, keeping max temperatures from being fully actualized. ...Next Week... High pressure builds across the region next week, allowing for a gradual warming trend with high temperatures warming to the 50s to near 70 (mainly for areas outside of stratus/fog development). Dry conditions will continue through next week. Some ensembles are indicating a weak pattern change in mid December but there is a large amount of uncertainty as it is too far out in time. && .AVIATION... Lingering low cigs and mist across the Central Valley continues into this evening, although some sites may very briefly return to VFR conditions around 22-24Z. Another round of BF/FG and low stratus returns tonight after 03Z and continues through Sunday, with areas of MVFR/IFR conditions. Areas of LIFR in fog and low ceilings around 12-18Z, particularly in the Central Valley from Sacramento southward. Lingering low ceilings in stratus expected to persist through the day. Light and variable surface winds less than 12kts. && .STO WATCHES/WARNINGS/ADVISORIES... None. && $$ ####018004354#### FXUS63 KABR 062112 AFDABR Area Forecast Discussion National Weather Service Aberdeen SD 312 PM CST Sat Dec 6 2025 .KEY MESSAGES... - Another round of light snow moves into north central South Dakota later this afternoon, continues southeast this evening. Around an inch or less accumulations with this system. - Band of light snow moves west to east Sunday (40-60%). Inch or less type accumulations. - Frontal passage Tuesday afternoon to generate northwest winds with gusts in excess of 50 mph through the evening/overnight. && .UPDATE... Issued at 311 PM CST Sat Dec 6 2025 Just a quick update to cancell the winter weather advisory for Spink, Clark, Hamlin and Deuel as the band of snow has shifted south of that area. && .DISCUSSION... Issued at 145 PM CST Sat Dec 6 2025 Pair of bands of snow continue this afternoon, one migrating out of the CWA into east central South Dakota, the other poised on our doorstep in North Dakota headed into Mobridge/Aberdeen. CAMS continue to support this second feature headed into our area to dissipate, with only an inch type accumulations. 1030+ mb high pressure system moves over North Dakota extending south southeast into the northeast of the state tonight. Warm advection as this feature retreats Sunday is enough to generate light snow thanks to about 5 microbars of lift in the dendritic growth zone AOA 700mb. This persists for a few hours before drying out in the DGZ and leaving us with just stratus. The next clipper is rather weak Monday evening, mainly across North Dakota. Milder 850mb temperatures, between +1 and +3C in the warm sector overhead during daylight hours, however NBM sky cover is suggesting little sunshine potential for the day. Light westerly flow and the cloud cover/milder air aloft will scour out the last of the Arctic airmass at least. The clipper that follows later Tuesday is the main feature to watch this week. This is a much stronger system, down to around 985'ish mb. A tight gradient, 20mb across the state, and pressure falls of 13 to 16mb ahead, and similar pressure rises in its wake, means fairly good transport of winds aloft to the surface. Ahead of the system, strong warm advection will still temper this somewhat, with 1/2km winds of 30 to 40kts. By 00Z Wednesday, that has increased to 50 to 65kts in the cold advection regime. BUFKIT mixed tool verifies with several sites mixing into that 60kt zone. EFI/shift of tails focuses on James valley west for those higher probabilities for 60+ mph wind gusts. What impact will 60mph winds have however, after a high temperatures Monday above freezing, and Tuesday near 40 degrees with rain showers. Depends on how much wrap around snow is generated, which at this point is relegated to the far northeast of the state. As such the main impact will be winds on high profiles vehicles and powerlines, but the snow that is around should be heavily modified and unblowable. Another clipper follows for Wednesday night, following a track south of the CWA. The Arctic airmass that has followed Tuesday's clipper isn't quite as cold, but cold enough that the NBM probability p- type is predominantly snow. NBM 25-75th QPF range is only about 0.1" however deterministic GFS is coming in closer to a 0.5" swath/band, so this may be smoothed out in extended ensembles given how far out it is. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 1130 AM CST Sat Dec 6 2025 Terminals KABR,KATY,KPIR,KMBG Tracking two areas of snowfall. The first is currently moving away from KMBG, clipping KABR and headed towards KATY. This is mainly responsible for MVFR VISBY/CIGS, with the worst of it (IFR VSIBY in SN) missing the main terminals in the CWA. Late this afternoon that second area coming down is expected to mainly impact KABR/KMBG with MVFR VISBY. Overall there will be little change to CIGS for all terminals through the TAF period. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...Winter Weather Advisory until 6 PM CST this evening for SDZ018- 019-022-023. MN...None. && $$ UPDATE...07 DISCUSSION...07 AVIATION...07