380 FXUS63 KGLD 060454 AFDGLD Area Forecast Discussion National Weather Service Goodland KS 1054 PM MDT Sun Sep 5 2021 .SHORT TERM...(This evening through Tuesday Morning) Issued at 136 PM MDT Sun Sep 5 2021 The forecast period begins with northwesterly flow over the area with an amplifying ridge over the western CONUS. A dryline is currently moving east over the CWA as dewpoints are in the mid 20s near Limon to 45 in Goodland and 60 in Colby. The dryline has the potential create enough lift for isolated storms mainly along and east of an Oberlin to Colby to Tribune. Visible satellite does show a CU field developing in that area as of 19Z. Forecast soundings over Gove county does indicate a cap in place around the 750mb level with 1300 j/kg of DCAPE, 2000-2500 j/k of MUCAPE, lapse rates around 8C and 30+knots of shear which would be sufficient for perhaps quarter size hail and 50-60mph wind gusts IF storms are are able to break the cap and form. If storms do form they should dissipate with the loss of diurnal heating through the afternoon. The other main issue is behind the dry is elevated to near critical fire weather conditions. The near critical conditions look to remain confined to east Colorado as the dryline has moved through there around 17-18Z. Afternoon highs continue to look on track in the mid to upper 80s to perhaps a few locales hitting 90. Overnight tonight looks to be clear as overnight lows fall into the 50s to low 60s across the entire area. For Labor Day, sunny and warm temperatures return to the area with afternoon highs in the 90s. Elevated to near critical fire weather conditions are again expected as RH values fall into the lower teens across east Colorado and the mid teens to low 20s towards Highway 25. Winds will again be the limiting factor with gusts around 15- 20mph throughout the afternoon. Overnight lows for Monday will be in the mid 50s to low 60s. .LONG TERM...(Tuesday through Sunday) Issued at 245 PM MDT Sun Sep 5 2021 The long term period from Tuesday through Sunday remains dry with the main concern being the potential for elevated to near critical fire weather conditions during the afternoon hours. The large area of high pressure aloft migrates from the Intermountain region on Tuesday across the 4-corners region on Wednesday and into the southern Rockies and southern High Plains on Thursday and Friday before it flattens and diminishes over the weekend as a series of upper short wave troughs move through the westerly flow along the U.S./Canadian border region. A trough/cold front at the surface moves east of the area early Tuesday with a slightly cooler airmass moving into the region that brings high temperatures back into the 80s and closer to normal for this time of year on Tuesday and Wednesday. On the back side of the surface trough/front, north/northeast winds may end up being a little stronger during the day on Tuesday than they have been in days prior given the increase in the pressure gradient around the surface trough. Fire Weather conditions may end up being elevated on Tuesday with an increase in the wind speeds, but with cooler temperatures on Tuesday and Wednesday, expect RH values to be above critical thresholds. However, with a transition to mostly south/southwest winds and temperatures back up in the middle to upper 90s on Thursday and Friday, expect the western sections of the forecast area along and west of the eastern Colorado border to see RH values down near or below the 15% critical threshold. Wind speeds may not be as high those days, so elevated to near critical fire weather conditions are expected rather than critical conditions. Another trough/front moves through the area on Saturday, bringing temperatures down a few degrees and the RH values up slightly for Saturday and Sunday. Conditions will still be dry, warm, and a little breezy during the afternoon, but fire weather conditions are not expected to reach critical values at this time on either of those days. && .AVIATION...(For the 06Z TAFS through 06Z Monday night) Issued at 1049 PM MDT Sun Sep 5 2021 For KGLD, VFR conditions are expected through the period. Winds will largely remain out of the south to southwest through the period at 10kts or less. For KMCK, VFR conditions are likely through the period. However, visibility has been dropping slowly the last few hours and fog/mist may develop early in the period. MVFR conditions may be possible should the fog or mist fully develop, but winds shifting to out of the southwest may limit development. Winds will start out light and variable before becoming southwesterly later in the night. The afternoon hours will see winds shift to out of the south at 10kts or less. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...TT LONG TERM...LOCKHART AVIATION...KAK