640 FXUS64 KAMA 222045 AFDAMA Area Forecast Discussion National Weather Service Amarillo TX 245 PM CST Fri Jan 22 2021 .SHORT TERM...Tonight through Tomorrow Night... Latest water vapor imagery shows next western NOAM upper trough digging southeast into northern CA and western NV. Mid/upper level moisture is spreading northeast across the Four Corners region, transitioning to drier mid level air over the southern plains. At the surface, light easterly winds have slowly veered to the southeast through the morning in response to weak lee pressure falls over Raton Mesa. This has resulted in low clouds in portions of the Texas Panhandle due to weak warm air advection and some upslope flow. The latest RGB imagery indicated dissipation of clouds along outer periphery near Dalhart and Borger, but they are still holding strong over KAMA. Have lowered high temperatures where clouds have held in the longest, and where temperatures were still in the 30s as of 19z. Clouds may finally get out of here by 21z or so, but that won't leave a lot of time to warm before the better sun angle is lost. For tonight, warm air advection regime continues as southwest flow aloft increases ahead of western NOAM trough. Model sounding profiles (even GFS to some extent) indicated a 50 to 100mb layer of saturation near the surface starting around 03z tonight in the southern TX Panhandle, then spreading northwest to cover most of the combined Panhandles by 06z. Short term models including the HREF mean and NARRE indicated some dense fog potential, especially after 06z tonight on the Caprock. Have thus included patchy and areas of fog/freezing fog depending on the temperatures (which will be right near freezing for southern zones). Fog headlines may be needed mainly between the hours of 06z Saturday and 18z Saturday, before surface winds become southwesterly and dry air invades. Otherwise, once the clouds and fog/drizzle clear out, temperatures should quickly climb. Current thinking is that the downslope effect will clear out the clouds in time to allow temperatures to rise into the 50s and 60s. However, high temperatures were lowered below NBM using blend of raw guidance and CAMS. Ward && .LONG TERM... Water vapor analysis shows a mid to upper level low digging south along the west coast of CONUS, located around northern California as of this writing. The base of this trough is to move south just off the coast of California with a positive tilt until the base of the trough is located just south of AZ Sunday morning. By Sunday evening this shortwave trough will be quickly positioned with a negative tilt as it starts to enter over the Panhandles. At least per the EC and CMC solution. The GFS keeps the trough oriented with more a positive tilt and speeds up the eastward progression. This system is looking to bring some PoPs to the combined Panhandles Sunday night into Monday. Sunday morning an associated surface front will move through the area but models show this cold front hanging up around the southern Texas Panhandle. This will create a nice gradient in daytime highs from the northern combined Panhandles to the southern Texas Panhandle. Winds will become more easterly in the afternoon as surface low continues its eastward progression. The aforementioned upper level trough will move into the area Sunday night with quite a bit of PVA according to the EC and CMC solutions with the negatively tilted trough. The NBM has been trending up with PoPs for the overnight period into Monday. The GFS has previously shown the FA getting dry slotted with this system. However, if the EC and CMC are correct the negatively tilted trough will make dry slotting less likely, but could also keep warmer air in place. Have stuck with the NBM PoPs which do have 70 PoPs in the east and 40 PoPs in the west. Late afternoon Sunday into early evening some instability will be present in the southeastern TX Panhandle and cannot rule out some thunder. MUCAPE is limited to less than 200 J/Kg. Any precipitation going into the evening will most likely be rain. The later it gets and temperatures start to drop, a brief period of freezing rain may be possible across mainly the northern half of the TX Panhandle before transitioning into snow. Eventually the northern combined Panhandles will turn to all snow. Even though PoPs range from a chance to likely, this could be an event where the amount of liquid precip received will not do much in the way of preventing degradations in drought for some areas. Further north in Kansas will be a different story as better moisture looks to be present. Therefore, not expecting much in the way of snow accumulations in the north until you get to about the KS state line. Generally less than an inch is expected at this time, with the exception of some isolated areas along the KS state line. With that said, if the upper level system moves further south than what is forecasted at this time, higher snow amounts along with its impacts will be of concern especially in the Oklahoma Panhandle and northern Texas Panhandle. Another thing to watch for will be the exact location of the cold front at the surface as temperatures will be playing an role in the rain snow line across the area. Model trends will have to be watched for southerly shifts in solutions leading up to Sunday night into Monday. In general, the ensemble members have been more generous with precip compared to the drier GFS, especially across the northern Panhandles. A second upper level system will move through Tue night into Wed that will potentially bring precipitation to the FA. Confidence in the system Tue night is low and have lowered chance PoPs given by the NBM down to slight chance in the northern FA, primarily the OK Panhandle. The low does look to be taking a northeast trajectory from the Four Corners Region up into IA at this time per deterministic solutions. Cool temperatures are expected through the week until Thursday when the area could see temperatures back in the 50s again. Hoffeditz && .PRELIMINARY POINT TEMPS/POPS... Amarillo TX 31 59 33 55 30 / 0 0 0 20 50 Beaver OK 25 57 30 47 25 / 0 0 0 5 70 Boise City OK 27 59 27 44 24 / 0 0 0 10 40 Borger TX 33 61 35 55 31 / 0 0 0 10 60 Boys Ranch TX 30 63 30 55 28 / 0 0 0 20 40 Canyon TX 30 61 32 57 30 / 0 0 0 20 40 Clarendon TX 32 57 37 57 34 / 0 0 0 20 60 Dalhart TX 27 60 27 49 24 / 0 0 0 20 40 Guymon OK 26 61 29 46 25 / 0 0 0 10 60 Hereford TX 31 61 32 59 30 / 0 0 0 20 40 Lipscomb TX 27 53 32 50 28 / 0 0 0 10 70 Pampa TX 30 57 34 53 30 / 0 0 0 10 60 Shamrock TX 30 51 37 57 32 / 0 0 0 20 70 Wellington TX 32 52 37 59 33 / 0 5 5 20 60 && .AMA Watches/Warnings/Advisories... TX...None. OK...None. && $$ 7/36