Area Forecast Discussion
Issued by NWS Oklahoma City, OK
Issued by NWS Oklahoma City, OK
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531 FXUS64 KOUN 170358 AFDOUN Area Forecast Discussion National Weather Service Norman OK 1058 PM CDT Thu May 16 2024 ...New AVIATION... .SHORT TERM... (This evening through Friday) Issued at 336 PM CDT Thu May 16 2024 Still a "wet" forecast in the short term until this current system exits Friday night, but less severe with much of this afternoon through tonight`s severe convection staying south of our CWA. An upper trough will continue to dig across the U.S. Southwest toward the Southern Plains with its axis bisecting our CWA by Friday afternoon. This trough will continue to expel shortwave disturbances downstream prior to its arrival although expecting most of them (with strongest vorticity) triggering elevated severe storms to stay south of our CWA. Although much of the elevated forcing and abundant surface moisture will be south of our CWA, we still have a surface boundary/stalled cold front stretched across our area with lower 60s dewpoints and weak mid-level capping on both sides of the stationary front and our western CWA is diurnally heating up. Much of our CWA is still weakly unstable (SBCAPE: 1000-2000 J/kg) with ample deep-layer shear south of I-40. As a result and with current convection already over northern Texas moving toward our western north Texas counties, will keep storm POPs at 60-70% across our southwestern CWA with a few strong but below severe. With the upper trough starting to move in, will keep storm POPs (up to 50-60%) through tonight although elevated instability is weak so convection should remain below severe as well as surface based CAPE with the stalled surface boundary should it start moving. Also added patchy radiation fog across the eastern two-thirds of our CWA for few hours mid-morning. Will maintain a marginal/low-end risk across southeast Oklahoma for Friday afternoon until this system exits out, with hail & winds as the potential severe hazards. && .LONG TERM... (Friday night through next Wednesday) Issued at 336 PM CDT Thu May 16 2024 The polar jet finally digs our upper trough to the east exiting our area as weak ridging from a now subtropical jet starts building over the Southern Plains through the weekend resulting in a heating trend. Further upstream a weak trough will be slowly digging across the eastern Pacific toward the Southern California coast which will be our next system to come through around Tuesday/Wednesday. Prior to this next systems arrival we will start heating up into the lower 90s by Sunday across the western half of our CWA to the upper 80s to the east. A surface low lee of the Colorado Rockies will start bringing a return circulation of strong southerly flow Sunday with strong low-level jets overhead both Sunday & Monday nights. As a result, gusty south winds will start Sunday afternoon and will likely stay windy through Monday night. Expecting to mix up to at least 850 mb off the surface Sunday and Monday afternoons so could see 30-35 mph gusts or possibly higher to near advisory criteria on Monday afternoon. Although NBM default windspeeds look fine for Sunday, did increase them for Monday afternoon by nudging 50% of the NBM 90th percentile winds. Monday may also be the hottest afternoon with all of our CWA heating up to the 90s, to upper 90s across far southwest Oklahoma and adjacent western north Texas. Our increasing southerly flow will also include gulf moisture transport forming a dryline through western Texas. With upper 60s dewpoints creeping in, Monday will also feel quite muggy, although windy conditions may provide some relief. Although we stay mostly dry until this Tuesday/Wednesday system comes through, will still maintain storm POPs (20-30%) across northcentral Oklahoma for both Sunday & Monday nights due to potential MCS activity expected mainly across the Central Plains/Kansas. Our next system comes through Tuesday into Wednesday which will push a cold front through although models differ with the handling of the dryline with the front overtaking the dryline with the GFS solution while the ECMWF does not punch the dryline through until late in the week. Either way, moisture advection will be strongest east of I-35 and quite unstable and strongly sheared ahead of the cold front for thunderstorm development. For now, will have storm POPs Tuesday afternoon and overnight across central through southeast Oklahoma and can`t completely rule out severe based on current model runs, although probabilities are still too low this far out but it will be a day to keep an eye on. Lastly will have storm POPs in for Thursday across central through southeast Oklahoma with a potential shortwave coming through, although keeping them low (20-30%) due to model differences with a wet GFS & NBM solution although the ECMWF keep us dry. && .AVIATION... (06Z TAFS) Issued at 1028 PM CDT Thu May 16 2024 Some showers/storms may impact SPS/LAW at the beginning of the forecast, but currently chances remain too low to mention. Some MVFR ceilings are expected to develop overnight. Could also see a period during the first part of the day for a few showers along and east of I-44 as upper trough moves across the area. Otherwise, skies will clear from west to east during the day and into the evening hours with light winds. && .PRELIMINARY POINT TEMPS/POPS... Oklahoma City OK 61 77 59 87 / 20 40 10 0 Hobart OK 59 78 58 89 / 30 30 0 0 Wichita Falls TX 62 78 60 89 / 40 40 10 0 Gage OK 54 82 57 91 / 10 0 0 0 Ponca City OK 60 78 58 86 / 0 20 0 0 Durant OK 62 79 62 87 / 30 50 20 0 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...None. TX...None. && $$ SHORT TERM...68 LONG TERM....68 AVIATION...30