972 FXUS63 KGLD 100956 AFDGLD Area Forecast Discussion National Weather Service Goodland KS 356 AM MDT Wed Oct 10 2018 .UPDATE... Issued at 758 PM MDT Tue Oct 9 2018 Precipitation has shifted northeast as was expected, however it has been more to the east than northeast. Have increased precipitation chances as a result over the southern part of the forecast area. Also looks like the precipitation has slowed down its eastward progression. May need to consider increasing snowfall amounts as a result. Regarding snowfall amounts, the western edge of Kit Carson and Cheyenne Counties have snowfall reports of 6" or so, with 2" in Burlington and northwest of St. Francis. With the majority of the snow east of CO, and roads remaining snow free so far as shown by webcams, do not plan on issuing any hazard at this time due to the snow. Icy roads will be the main impact as the temperature falls tonight. UPDATE Issued at 500 PM MDT Tue Oct 9 2018 Main change to the forecast was to increase precipitation chances in the west under the band of snow and reduce them in the east where lift is lacking. Frontogenesis in the 700-500mb layer over East Central Colorado seems to be responsible for the band of snow there. Am expecting the frontogenesis to shift northeast somewhat quickly over the next few hours, taking the band of snow with it. Snowfall will be highest over East Central Colorado where the snow band has lingered the longest. May see amounts approach 3 inches on elevated or grassy surfaces. So far none has accumulated on the highways. The frontogenesis will exit the forecast area before midnight, bringing the snow to and end by or not long after midnight. Meanwhile the small area of higher reflectivity over the now central part of the forecast area may maintain its intensity due to it riding the gradient of lower stability as it moves north. && .SHORT TERM...(This evening through Wednesday) Issued at 307 PM MDT Tue Oct 9 2018 Inverted trough will lift to the northeast and move out of our area overnight tonight. This will allow us to clear out and help our temperatures to drop even further. Issued a Freeze Warning tonight as a result for counties along and west of Highway 25. For all counties east of Highway 25, issued a Frost Advisory. Confidence on the Freeze Warning is high, while the confidence of the Frost Advisory is medium. Depending on cloud cover tonight, and gusty northwest winds it may prevent widespread frost from developing. Dryer conditions expected on Wednesday, and with clearing skies and reduced winds, confident we will drop further and have to issue additional frost/freeze headlines. Prevented doing so this forecast period to prevent confusion. .LONG TERM...(Thursday through Tuesday) Issued at 355 AM MDT Wed Oct 10 2018 The orientation of the jet stream over the weekend and into the middle of next week remains extremely meridional with upper-level winds diving southward out of Canada into the Plains states inviting with it unseasonably cold air. The flow reflects down into the mid- levels and is such that a deep longwave trough remains to our west, producing and ejecting multiple disturbances throughout the period with two well-defined cold frontal systems expected to pass...one Saturday evening into Sunday morning and another Tuesday evening into Wednesday morning. Coldest temperatures will occur on Sunday behind the stronger of the two cold fronts, with max temps topping out in the upper 30s across most of the region and subsequent low temperatures in the lower 20s. Temperatures were adjusted downward form the initial output of the Superblend considering the extend of the mid-level CAA with very tight packing of almost 10 degrees at 850 mb according to the GFS and winds out of the due north averaging 30 kt as the front passes over NW Kansas. Moisture is also quite extensive, thus leading to steady snow showers over almost an entire 24 hour period. Current snowfall amounts for Sunday are estimated to be somewhere in the neighborhood of half of an inch to an inch. Subsequent model runs will provide a better prediction of the finer details related to this front such as timing, placement with reference to timing, timing, duration and severity of snow showers as well as more accurate temperature fluctuations. The ECMWF also displays a roughly 10 degree temperature differential at 850 mb behind the front and is several degrees colder than the GFS. The ECMWF is considerably more moist also and was the model of choice among neighboring offices during collaboration discussions. The second frontal passage expected to occur Tuesday night into Wednesday morning is considerably weaker with a much less-defined thermal gradient, thus not much of an impact on temperatures is expected to occur behind that front. Most precipitation chances associated with this front will remain confined to the eastern sector and generally below 40%. With respect to the other elements of this forecast period, no significant precipitation is expected aside front the rainshowers which give way to snow showers as the front progresses southeastward across the area on Sunday as well as the 40% chances for Wednesday in the eastern sector. Temperatures remain fairly steady with the exception of Sunday. Max temps in the mid-to-upper 50s are expected for all other days with a gradual warming trend from Monday through Wednesday. Hopefully as the jet pattern shifts downstream and brings a longwave ridge into the area, we will see temps rise again and break out of the 50s and possibly into the upper 60s by Friday of next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1138 PM MDT Tue Oct 9 2018 MVFR to VFR conditions forecast for the TAFs. Both sites should be MVFR through the rest of the night as the precipitation exits to the northeast. Ceilings may improve to VFR faster than what is currently forecast, but hopefully that won't be until after 12z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...Hard Freeze Warning from 11 PM MDT /midnight CDT/ this evening to 10 AM MDT /11 AM CDT/ Thursday for KSZ001>004-013>016. Freeze Warning until 10 AM MDT /11 AM CDT/ this morning for KSZ001-002-013-014-027-028-041-042. Frost Advisory until 11 AM CDT this morning for KSZ003-004-015- 016-029. Hard Freeze Watch from this evening through Thursday morning for KSZ027>029-041-042. CO...Hard Freeze Warning from 11 PM this evening to 10 AM MDT Thursday for COZ090-091. Freeze Warning until 10 AM MDT this morning for COZ090>092. Hard Freeze Watch from this evening through Thursday morning for COZ092. NE...Hard Freeze Warning from 11 PM MDT /midnight CDT/ this evening to 10 AM MDT /11 AM CDT/ Thursday for NEZ079>081. Freeze Warning until 10 AM MDT /11 AM CDT/ this morning for NEZ079-080. Frost Advisory until 11 AM CDT this morning for NEZ081. && $$ UPDATE...JTL SHORT TERM...EV LONG TERM...SANDERSON AVIATION...JTL