####018005895#### FXUS65 KRIW 260351 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 951 PM MDT Thu Apr 25 2024 .KEY MESSAGES... - More widely scattered rain showers and isolated thunderstorms this afternoon and evening. - Main system pushes through Friday night and into the weekend with ample mountain snow and low valley rain. - Warming trend and mainly dry next work week with another system late week and into the following weekend. && .DISCUSSION... Issued at 1236 PM MDT Thu Apr 25 2024 IR currently depicts the deep trough over the western CONUS with cooling cloud tops through the CWA advecting in from the southwest. Radar shows a much more sporadic day ahead with widely scattered rain showers and some isolated thunderstorms. This will continue through the afternoon and early evening hours before subsiding with radiational cooling and the eventual FROPA of a cool front. This is pushing into northwestern portions of the state and will slowly move southeast throughout the remainder of the day. Temperatures behind it are not much cooler around 10 degrees from yesterday, but more seasonable in the days ahead over the weekend. With these rain showers and thunderstorms, there is enough instability of DCAPE to see some gustier outflows for southern counties and those east of the Divide from Wind River Basin to the I-25 corridor. Updraft is not strong enough to see any type of hail growth or potential for anything severe at this time. The prone area with the best potential will be well east of the CWA into far reaches of the state in eastern Wyoming and points southeastward. Otherwise, a decent rain fall, even for the higher terrain expected for the rest of today with the better bullseye further east from Casper to Buffalo dependent on where any showers/storms entrain upon one another. This first initial shortwave off the main low coming in from the Pacific northwest overnight into much of Friday. Initial waves of snowfall to the higher terrain of the Absarokas and Bighorns expected by mid afternoon spreading to the Winds by the evening. Fairly slow moving over the weekend, substantial snowfall expected with the Winds the highest amounts up to 1.5 to 2 feet with other ranges up to a foot possible. The better dynamics and 700mb trough orientation looks to set up off the Absarokas to the Winds with the highest probabilities over 18 inches of 80-90 percent. Over 12 inches with a 60-70 percent probability elsewhere at this time. Regardless, winter highlights have been issued to cover these ranges. Minor accumulations with little to no impacts with the warmer temperatures for lower areas west of the Divide. Liquid precipitation is expected for the lower valleys east of the Divide where the southern counties to be the possible winners for the weekend. All areas need the moisture, but especially this area. However, a minor flooding impact is possible and something to keep an eye on where up to an inch is possible. QPF amounts have come down as expected being a more progressive than expected system. Less than half an inch for other points to include the Wind River and Bighorn Basins, as well as along the I-25 corridor. Confidence on the liquid precipitation amounts are not as high as the snow, being more of medium confidence at this time as models are not in great agreement with one another. Beyond the weekend, expect a warming trend and mainly dry conditions for next work week as upper level ridging builds in with increasing convergence aloft. Back to above average temperatures and some windier days ahead for next week but hopefully this overall system's QPF amounts helps to alleviate any fire weather concerns in the more long term. Beyond that, long term models and outlooks show another GOA low pushing down that could affect the CWA by next weekend hopefully to bring in more of the much needed moisture. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 950 PM MDT Thu Apr 25 2024 A very active weather pattern continues through the next 24 hours. An area of rain showers will develop from the Bighorn Basin down to Natrona County tonight/early Friday morning. Rain chances increase at KCOD/KWRL/KCPR terminals near/shortly after sunrise, so have prevailing -SHRA at that time. For other terminals it will remain dry tonight with more convective showers developing late Friday morning/early Friday afternoon across the area. For now have -SHRA for most terminals Friday afternoon, but -TSRA may be added with the next TAF issuance if confidence is high enough. There will be thunderstorms, but the exact location/timing is too difficult to pinpoint at this time. A more widespread -RA will develop Friday evening from KRIW/KLND terminals down to KRKS/KBPI/KPNA terminals. For KCPR/KWRL terminals showers exit to the southwest by mid- afternoon Friday. MVFR conditions are likely (70%) at KCOD by 10Z/Fri as low clouds develop and hang around through Friday afternoon. Improvement should occur at KCOD late Friday afternoon/Friday evening as clouds begin to lift and -SHRA shift to the southwest. For most terminals VFR conditions will prevail through the TAF period. Mountain obscuration will increase Friday afternoon and be prevalent Friday evening. Have VCTS at KRKS Friday afternoon and included a variable gusty wind to account for thunderstorm downdrafts/outflows. && .RIW WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from noon Friday to 3 PM MDT Saturday for WYZ002. Winter Storm Warning from 6 PM Friday to 9 PM MDT Saturday for WYZ015. && $$ DISCUSSION...Lowe AVIATION...Rowe ####018004193#### FXUS64 KOUN 260353 AFDOUN Area Forecast Discussion National Weather Service Norman OK 1053 PM CDT Thu Apr 25 2024 ...New AVIATION... .SHORT TERM... (This evening through Friday) Issued at 234 PM CDT Thu Apr 25 2024 Overnight tonight, storms are expected to initiate east of Lubbock and move into far western north Texas. Large scale ascent with the approach of a mid-level wave, will help these storms to become more widespread into a line of storms. The northern extent of this line is still in question, but the most likely areas to be affected are locations south of I-40 and along and east of I-44. The parameter space ahead of this line will continue to support damaging winds up 80 mph, and a few embedded QLCS mesovortices. The line of storms is expected to move out of the area by the mid morning Friday. A dryline will be stalled west of I-35 throughout the day Friday. Although the mid-level forcing will be off to the east, with little inhibition, sufficient CAPE and shear, there will be a low chance for redevelopment Friday afternoon with all hazards possible. Near critical fire weather conditions are expected across western Oklahoma as sustained winds of 15-20 mph and RHs in the teens will be likely behind the dryline. Bunker && .LONG TERM... (Friday night through next Wednesday) Issued at 234 PM CDT Thu Apr 25 2024 Saturday: Saturday still has the potential for significant severe weather across the entire area. Moisture return will move in quickly ahead of another advancing negatively-tilted mid-level trough. A dryline will once again sharpen across the Oklahoma/Texas panhandles/state line as a surface low deepens in southwest Kansas. There are still model uncertainties with the overall evolution of this system, however. Timing of the mid-level trough will greatly impact when the large scale ascent overspreads our area, and if convection can stick around Saturday morning, that will likely hamper convection later in the afternoon. A slower trough ejection (which is currently being shown by the NAM) and morning convection will limit severe potential, but if there is no morning convection and the timing of the wave coincides with peak heating, multiple rounds of significant severe weather will be expected will all hazards possible. Given the parameter space, there is even the chance that any morning convection that does form, may become severe. These mesoscale details will most likely not be realized until closer to the event, as globals models tend to do poorly with sub-synoptic scale details. In any of these scenarios, it is vital that you remain weather aware throughout the WHOLE day Saturday, even after sunset. Figure out your plan NOW, and make sure you are ready to act when a warning is issued. By Sunday, showers and thunderstorms will continue to move out of the area with weaker flow aloft. Higher heights will move in by early next week, with a warm up into the 80s by Tuesday and low chances for thunderstorms. Rain and thunderstorm chances return during the middle parts of next week. Bunker && .AVIATION... (06Z TAFS) Issued at 1040 PM CDT Thu Apr 25 2024 MVFR ceilings are expected to persist into Friday morning at most TAF sites. A line of thunderstorms is expected to enter western Oklahoma after 06z and move into central Oklahoma before sunrise. Some severe storms with large hail are expected. Storms will move east of all TAF sites apart from KDUA around 13z. Gusty south winds will persist. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 64 82 65 77 / 80 20 0 90 Hobart OK 60 85 61 80 / 80 0 0 70 Wichita Falls TX 64 85 65 78 / 90 10 0 80 Gage OK 56 86 55 86 / 30 0 0 40 Ponca City OK 63 83 65 80 / 90 20 0 80 Durant OK 66 79 68 81 / 80 70 20 70 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ SHORT TERM...13 LONG TERM....13 AVIATION...09