Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 02/08/21


Area Forecast Discussion
National Weather Service Dodge City KS
936 PM CST Sun Feb 7 2021 .UPDATE... Issued at 936 PM CST Sun Feb 7 2021 Updated to expand the winter weather advisory to include Scott county to match WFO Goodland. Continued to leave out Hays and the I-70 corridor, where the air is colder and notably drier, and the boundary layer is much further from saturation at present. This may change later tonight and bears watching. 00z NAM continues to show a strong light QPF/drizzle signature overnight into early Monday across much of SW KS, favoring the central/eastern zones. Much of this QPF (<0.10") should take the form of freezing drizzle resulting in light icing on exposed surfaces. With temperatures so far below freezing, this icing process will be efficient overnight, despite modest QPF. Roadways and sidewalks will be slick and hazardous in the morning. Further north in the deeper cold air, more of this light precipitation will take the form of light snow. Additionally, freezing fog will continue to lower visibility to less than 1 mile at times, adding to the overnight hazards. && .SHORT TERM...(This evening through Monday) Issued at 334 PM CST Sun Feb 7 2021 Shallow cold airmass was firmly entrenched across southwest and west central Kansas. The first round of very light freezing drizzle waned around midday, but freezing fog continued across far southwest Kansas (except Elkhart!) as of 21Z. Elkhart broke out into sun finally, with their temperature shooting up to around 50 degrees. Just east of there at Hugoton, it was 29F. Now that we have reached the diurnal maximum of the day, the very slight northeastward advancement of the warm air will cease. Surface winds out of the south-southeast will back around to the east later this evening, which will keep freezing fog in place, and even expanding in coverage overnight. Another round of shallow layer warm advection will develop tonight, supporting development of freezing drizzle and snow flurries. This morning, we observed freezing drizzle in Dodge City with a 0-1km AGL minimum temperature around -11C, which is about the lower limit for freezing drizzle vs. light snow, as in most cases, ice nuclei activates -10C or colder, and almost always - 15C or colder. It will be -12C or colder generally north of the Arkansas River tonight, so areas north of the Arkansas River will likely see more off and on flurries instead of freezing drizzle. That said, any little bit of freezing drizzle will cause additional slick spots tonight. We have expanded the Winter Weather Advisory west to the Colorado border and extended it out to 18Z Monday. Much of the event farther west will be freezing fog, but even out toward the Colorado border, there may be enough turbulent mixing and enough of a saturated layer to support some light freezing drizzle, mainly after 06Z tonight. After 06Z, the surface winds will continue to back around to a more northerly component, and this will resume the surface cold advection. This should help suppress the freezing drizzle area to just areas closer to the Oklahoma border by daybreak Monday before the entire shallow layer precipitation area shifts east deeper into central Kansas. Monday`s weather will be much like today, socked in low stratus clouds except breaking out in the west later in the afternoon. High temperature Monday will again be a challenge, with another day of a fairly high gradient in highs from 42F at Elkhart to 13F at Hays. .LONG TERM...(Monday night through Sunday) Issued at 334 PM CST Sun Feb 7 2021 The arctic cold wave is expected to continue through the entire Long Term period through Sunday. Highs in the teens to lower 20s are expected every day Tuesday through Sunday, although confidence in the duration of the cold wave is still fairly low after Saturday. The ECMWF is a little warmer now on its 12Z run for the latter portion of the Long Term period, however the GFS and Canadian models are still quite bullish on keeping the brutally cold airmass going through the late weekend, 14 February. The next wave to bring any accumulating snow to western Kansas looks to be around Friday Night- Saturday, but synoptic details are still sketchy at best with the three major deterministic models GFS, Canadian, ECMWF all singing a different tune. So, confidence in a big snow event affecting southwest Kansas during or toward the end of this cold wave is still fairly low at this time. That said, today`s runs of the global models are starting to show a larger scale system developing across the West late weekend, moving out across the central CONUS Sunday Night into Monday. Again, this is a week away, so there is plenty of time to watch and see how this unfolds in the numerical prediction realm. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 443 PM CST Sun Feb 7 2021 High confidence that very poor aviation conditions will continue through the balance of this TAF cycle, with the terminals entrenched in shallow arctic air near the surface. Widespread LIFR stratus ceilings late this afternoon will only reestablish and/or lower further after sunset. In addition, reduced visibility will continue in BR/FZDZ/FZFG, down to 1/4 sm at times (VLIFR). Light icing on runways and aircraft will continue, particularly in areas where freezing drizzle is predominant versus snow flurries. Given today`s trends, and the fact that arctic air will only be reinforced Monday, kept TAFs for daylight Monday very pessimistic, with stratus persisting at all airports through the daylight hours. With a drier boundary layer, surface visibility over 6 sm should be maintained at HYS, although IFR stratus is expected at HYS as well. E/SE winds of 10-15 kts presently will back to NEly at similar speeds tonight through Monday. && .PRELIMINARY POINT TEMPS/POPS... DDC 11 21 8 20 / 20 10 0 0 GCK 11 25 9 22 / 20 10 0 0 EHA 23 42 15 31 / 10 0 0 0 LBL 19 33 14 25 / 10 0 0 0 HYS 5 15 2 11 / 20 10 0 0 P28 17 22 11 19 / 20 20 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until noon CST /11 AM MST/ Monday for KSZ043>046-061>066-074>081-084>090. && $$ UPDATE...Turner SHORT TERM...Umscheid LONG TERM...Umscheid AVIATION...Turner