269 FXUS64 KAMA 211144 AFDAMA Area Forecast Discussion National Weather Service Amarillo TX 544 AM CST Wed Dec 21 2022 ...New AVIATION... .SHORT TERM ... (Today through Thursday night) Issued at 340 AM CST Wed Dec 21 2022 Bottom Line Up Top: 1. A strong cold front will blast through the area tonight with temperatures plummeting into the single digits to a few degrees below zero in it's wake. 2. Wind chill values as low as 25 to 35 degrees below zero are expected Thursday morning, with only slight improvement going through the day. These wind chill readings can cause frostbite very quickly. 3. Windy conditions are expected through Thursday morning, possibly lasting into Thursday afternoon before decreasing some Thursday evening (but still remaining breezy). The first few hours directly in the wake of the cold front will have at least a small chance (<20%) for a damaging wind gust possibly in excess of 60 mph. 4. The sub-freezing temperatures will be in place at least through Friday night (with most of that time being well below 20 degrees). The western half of the area has about a 50 percent chance of temperatures rising above freezing on Saturday, but in the east chances are not that good. Exposed or poorly insulated pipes could burst. 5. Right now, even though a good portion of the area may fall near or even a few degrees below zero Thursday morning and again Thursday night, it looks like current record lows will stay intact. The same can be said for record low highs. 6. Some freezing fog or perhaps even some very localized freezing drizzle will be possible this morning (several ob sites confirm the FZFG), but should clear about by 10 AM. Some industrial snow is also possible given the saturated conditions near the surface, but chances are low for anything impactful. 7. Another round of light snow is possible for a few hours behind the front, mainly favoring the northeastern area where slightly better mid level moisture will exist. Right now, the chances for a dusting are only about 20 to 40 percent. Chance for anything impactful are less than 10 percent. Industrial enhanced snow is possible. Technical Discussion: The latest upper level analysis places a double barrel upper low over Canada resulting in broad cyclonic flow over most of the CONUS. At the surface, very cold air exists over the northern plains where temperatures are 5 to 10 degrees below zero. Closer to home, temperatures were hovering in the upper 20s to near 30 with similar dew points resulting in areas of freezing fog (advection fog). Water vapor imagery depicts a subtle shortwave crossing the southern Rocky Mountains which is helping bolster the return flow and midlevel clouds are being detected on radar in the northern zones (seeder feeder snow possible but unlikely due to very dry layer between 800mb and 600mb). Some freezing drizzle/fog has also been reported near Liberal KS where the ASOS was reporting UP and -SN. Model soundings do support some freezing drizzle up in that area so have added Beaver Co to the Freezing Fog Advisory which concludes at 16z. As the western low over Canada amplifies today it will help send the very cold arctic airmass over the northern plains straight south through the Panhandles by tonight. Ahead of the front, a lee low will develop this afternoon in northeast NM which should help dry out the area some on increasing southwesterly winds. Would not be surprised to see mid to upper 50s area wide this afternoon on the breezy southwest winds. Those temperatures will come crashing down as a 1040mb to 1050mb area of surface high pressure expands through the plains. The temperatures gradient will be significant along with the height rises behind the front (possibly over 4mb per hour in some locations). Some locations could see temperatures fall some 20 degrees in one hour tonight. And highs in the 50s to near 60 today will fall to a few degrees below zero by Thursday morning. The wind will be strong, but just how strong is a little uncertain. The latest models suggest 850mb winds will be approaching 50 knots, and the strong CAA will allow for some mixing of the lowest 100mb or so. Right now the best chance for a 50 knot gust will be across the eastern zones where the 850mb jet is expected to be strongest. Sustained winds may be the bigger issue given the sharp pressure rises, with the strongest winds expected between 06z and 18z Thursday. The bigger impact will be the wind chill values which may approach 35 below zero Thursday morning. Wind chill readings won't improve much through Thursday night. Wind chill reading should finally rise above zero Friday afternoon. Soundings do show a 4-8 hour window behind the front Thursday where mainly flurries will be possible due to a shallow saturated layer around 850mb to 750mb. There is a chance of a little more than just flurries in the northeast zones where a 500mb jet streak sets up some better lift and moisture. Some very light snow accumulations (<1/2") are possible before noon Thursday in portions of Beaver Co. As for factory effect snowfall, there is a chance for some this morning due to the strong inversion with saturated condition near the surface. However, temperatures are not cold enough for dendritic growth this morning and the boundary layer winds are on the strong side, so anything more than a few very small snowflakes seems unlikely. For tonight and tomorrow behind the front, there may be too much dry air right near the surface and wind will be even stronger in the boundary layer, so factory effect snow seems unlikely. Ward && .LONG TERM ... (Friday through Tuesday) Issued at 340 AM CST Wed Dec 21 2022 Keeping an eye on Friday and Sunday night for possible precip, but warming trend on the way. By Friday, the upper level closed low will cross through the Great Lakes region and into the northeast. Ridging will build in the western CONUS. Shortwaves are projected to ride through the flow. A few ensemble members indicate that light precip could be possible Friday afternoon and again on Sunday night into Monday morning from shortwaves crossing the Panhandles. Other ensemble members push the shortwaves through other locations, keeping the CWA dry. For now have maintained the dry NBM. If precip does happen Friday afternoon, it would be snow flurries since temps will still be recovering from the bitter arctic blast. By Saturday, surface temps finally return to southerly and upper level ridging begins to push into the Southern Plains. This pattern will begin the temperature climb for the remainder of the extended period. A weak front looks to make an appearance at the end of the weekend into the beginning of next week, but it doesn't look to have much affect on temperatures. By mid week, the Panhandles will see the return of fall like temps that are above normal for the tail end of December. Beat && .AVIATION... (12Z TAFS) Issued at 536 AM CST Wed Dec 21 2022 IFR/LIFR conditions at KAMA and KGUY will continue through about 16z this morning with both low cigs and areas of freezing fog. Visibility has improved across the area over the last couple hours, but KAMA continues to bounce anywhere from 1 to 5 SM. VFR should dominate after 17z as breezy southwest winds commence. A strong cold front will bring north wind starting around 05z Thursday in the north to 09z in the south. Winds may gust over 40 knots behind the front, and a 50 knot gust can't be ruled out. A period of low cigs (MVFR/IFR) and -SN is also possible at the end of the period, especially for KGUY. Ward && .PRELIMINARY POINT TEMPS/POPS... Amarillo TX 58 2 10 1 / 0 0 10 0 Beaver OK 54 -5 6 -6 / 10 20 20 0 Boise City OK 57 -6 4 -6 / 10 10 10 0 Borger TX 59 3 11 1 / 0 0 10 0 Boys Ranch TX 60 2 12 0 / 0 0 10 0 Canyon TX 58 4 12 1 / 0 0 0 0 Clarendon TX 54 6 13 3 / 0 0 0 0 Dalhart TX 58 -4 8 -4 / 0 0 10 0 Guymon OK 57 -6 5 -6 / 10 10 20 0 Hereford TX 59 5 14 0 / 0 0 0 0 Lipscomb TX 52 -2 8 -4 / 0 10 10 0 Pampa TX 56 1 9 -1 / 0 0 10 0 Shamrock TX 49 5 12 3 / 10 0 10 0 Wellington TX 51 9 15 5 / 10 0 0 0 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...Wind Chill Warning from midnight tonight to noon CST Friday for TXZ001>020-317. Freezing Fog Advisory until 10 AM CST this morning for TXZ004- 005-008>010-012>015-017>020-317. OK...Wind Chill Warning from midnight tonight to noon CST Friday for OKZ001>003. Freezing Fog Advisory until 10 AM CST this morning for OKZ003. && $$ SHORT TERM...07 LONG TERM....16 AVIATION...07