559 FXUS64 KOHX 092323 AFDOHX Area Forecast Discussion National Weather Service Nashville TN 623 PM CDT Tue Oct 9 2018 .UPDATE... FOR 00Z AVIATION DISCUSSION. && .DISCUSSION... Radar imagery this afternoon shows a few showers over our southeast counties although all other areas remain dry. Temperatures have warmed to well above normal levels for this time of year into the 80s for most locations, except on the Plateau where cloud cover has kept temperatures down in the 70s. No notable changes have been made to the forecast from previously. A large upper trough currently in the Plains states is still depicted well on all model guidance to swing eastward into the Mid-South and Ohio Valley on Wednesday. As this occurs, it will force a strong cold front eastward into Tennessee late tomorrow into tomorrow night. With plenty of moisture and lift available ahead of the front, anticipating an increase in shower activity overnight tonight with a further increase in showers and a few thunderstorms tomorrow. Highest precip chances look to be Wednesday night as the frontal boundary moves across the cwa. This same upper trough will act to deflect Hurricane Michael well off to our east tomorrow and tomorrow night, with no direct impacts from the hurricane expected in Middle Tennessee. However, Michael may rob a substantial amount of the Gulf moisture that would otherwise be available ahead of our cold front, leading to lower overall precip amounts for us. Nevertheless, have kept pops on the high side in line with latest guidance. All rain should quickly end from west to east on Thursday, with our first Fall airmass arriving from the northwest. With the unusually warm weather that has affected Middle Tennessee since early September, it will likely be shocking to most as temperatures fall into the 40s by Friday morning and highs struggle to reach the 60s by Friday afternoon. Models begin to differ over the weekend with the ECMWF showing a much more significant warmup back into the 70s to near 80 by Sunday, while the GFS remains cooler in the 60s to near 70. Have split the difference for now until better model consensus emerges. Both global models do agree, however, that another shot of showers and storms will arrive Sunday night into Monday as another strong cold front pushes across the Tennessee Valley. && .AVIATION... 00Z TAF DISCUSSION. Some MVFR cigs can be expected around sunrise Wednesday morning as low-level moisture continues to increase ahead of an approaching frontal system. VFR should return during the mid-morning hours for all terminals. Winds will pick up out of the south a little Wednesday morning, too. Gusts of 15-20 kts can be expected through early evening ahead of a broken line of showers and thunderstorms expected to arrive towards the end of this TAF cycle. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ DISCUSSION......Shamburger AVIATION........Unger