208 FXUS63 KDDC 162326 AFDDDC Area Forecast Discussion National Weather Service Dodge City KS 626 PM CDT Sat Jun 16 2018 ...Updated Aviation Discussion... .SHORT TERM...(This afternoon through Sunday) Issued at 1200 PM CDT Sat Jun 16 2018 Widespread thick cirrus, associated with the remnant outflow circulation aloft of the former Pacific hurricane Bud, has overspread SW KS as of midday. Despite the cirrus this afternoon, temperatures will still warm well into the 90s, and south winds will again be strong, gusting 40-45 mph. An interesting forecast scenario unfolding for tonight. 12z NAM develops widespread convection, associated with the remnant Bud circulation, through 7 pm across SE Colorado to NE New Mexico. This development is already beginning per satellite imagery across eastern New Mexico as of noon. The NAM is by far the most bullish model with this development, and its eastward advance into SW KS tonight, with very heavy rainfall depicted. Evidently, 12z NAM is picking up on some spurious vorticity max in the remnant tropical circulation, interacting with a very moist atmosphere (precipitable water to 1.8"). While moist, instability on NAM is quite poor, to be expected in a moist adiabatic tropical environment, with CAPE only near 500 J/kg. Was ready to discount the 12z NAM wet solution, but now the 12z GFS is picking up on something very similar, spreading moderate to heavy rain west of US 83 through midnight before weakening. Given this agreement, and strong support from HRRR and other CAMs, had no choice but to increase pop grids dramatically into the likely category across the western zones this evening. Additional increases to the chance/scattered category were necessary further eastward tonight, as the anticipated band of rain/thunder weakens. Have high confidence on rain tonight for the western zones (some of it heavy), but have very low confidence on how far east this rain will advance. Additional refinements in pop/QPF grids expected. Temperatures tonight will struggle to fall in a moist/cloudy airmass, with many locations holding above 70 through Sunday morning. Any rainfall will dissipate rapidly around sunrise Sunday. Strong south winds will return once again after 10 am, averaging 25-35 mph, ahead of a cold front draped from near Limon Colorado to near North Platte Nebraska by 7 pm. Rich moisture and modest instability along the prefrontal trough will likely yield scattered thunderstorm development Sunday afternoon. With weak shear, severe hail/wind is not expected, but with high PWs and a remnant tropical airmass sticking around, locally heavy rainfall is likely. .LONG TERM...(Sunday night through Saturday) Issued at 217 PM CDT Sat Jun 16 2018 The daylight hours on Monday will be dry for most locations, as a weakening/stalling frontal boundary sags into the region. 12z ECMWF drapes this front across the N/NE zones Monday evening, and favors the NE zones near Hays for convective development. This matches well with SPCs Day 3 marginal hail/wind probabilities. Pop grids favor the eastern counties, and are confined mainly to the evening hours. With the front in vicinity weakening the pressure gradient, we will finally enjoy a break from the Kansas winds on Monday, reduced to 10-20 mph. Still plenty warm with highs in the lower 90s. Synoptic pattern for Tuesday and Wednesday continues to look interesting. 12z MEX guidance continues to crank pops into the likely range (60-70%) during this time frame, and these values were accepted for the forecast. Locally heavy rain is likely, as a stalled frontal boundary interacts with a moist atmosphere and disturbances in westerly flow aloft. Around a closed 577 dm 500 mb low in Montana, ECMWF depicts various shortwaves ejecting over the plains late Tuesday through early Wednesday, resulting in thunderstorm complexes (MCSs) across much of Kansas. Some storms may be severe with hail/wind potential, given the boundary and improved shear, but the main message is another opportunity for beneficial rainfall. Additionally, heights and thickness begin to drop off on Tuesday, yielding milder afternoon highs in the upper 80s. By Wednesday, a rather odd synoptic pattern for June is evident, with a closed low over Nebraska. Associated cold front will approach the northern zones by late day, but even without that, heights and thicknesses will continue to decline, forcing temperatures to remain more squarely in the milder 80s. Pending cloud cover, some locales may hold in the 70s as some bias- corrected guidance suggests. Closed low is forecast to drift into the Corn Belt Thursday and Friday, keeping NWly flow aloft, and preventing heat from returning. Afternoon temperatures in the 80s will be common. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 623 PM CDT Sat Jun 16 2018 Low level winds over the next 12 hours will behave much like the last two days. The gusty south to southeast winds at 20 to 25 knots early this evening will fall back to around 15 knots by midnight. Also overnight the south winds in the 1500 to 2000ft level will increase to greater than 40 knots after midnight based on the latest RAP and NAM BUFR soundings. Low level wind shear criteria at this time however it will be close. As a result will still include low level wind shear into the 00z TAFS. Clouds will be on the increase overnight across western Kansas along with a chance for thunderstorms, especially along and west of Highway 283. Also along with the chance for thunderstorms the ceilings are also expected to lower into the MVFR category at Garden City, Liberal, and even Dodge City between 06z and 15z Sunday. Moderate to brief heavy rainfall possible so visibilities as low as 1-2 miles can be expected at times in the steadier and heavier showers. && .PRELIMINARY POINT TEMPS/POPS... DDC 74 94 72 93 / 30 20 10 20 GCK 72 92 68 91 / 60 20 10 10 EHA 65 90 64 90 / 80 10 10 10 LBL 72 92 69 92 / 60 30 20 10 HYS 76 94 72 91 / 20 20 20 10 P28 76 96 74 95 / 10 10 0 20 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Turner LONG TERM...Turner AVIATION...Burgert