textproduct: Goodland

KEY MESSAGES

- Isolated to widely scattered thunderstorms will develop in the Kansas and Colorado border area by late this afternoon or early this evening, mainly south of Interstate 70. A supercell or two will be possible, capable of producing hail up to golf ball size or larger, damaging wind gusts and perhaps a tornado through about 9 PM this evening, followed by weaker and more isolated storms through the overnight hours.

- Isolated to widely scattered storm chances continue for Thursday and Friday, mainly in the afternoon and evening hours. Best chances both days will generally be east of Highway 25 in Kansas and Nebraska, where a stronger storm or two could produce large hail, damaging winds and a brief tornado.

- Expect near normal temperatures today followed by a warming trend through the weekend with temperatures well into the 90s.

SHORT TERM /THROUGH SATURDAY NIGHT/

Issued at 1245 PM MDT Wed Aug 19 2026

Upper ridge over the Four Corners today will strengthen the next several days as well as move east, located over Colorado by Friday and the central high plains by Saturday. Northwest flow on the eastern periphery of the ridge through Friday will result in isolated thunderstorm chances with embedded weak disturbances. Wind shear will be sufficient for at least some risk of a few isolated supercells in this pattern. Temperatures will also be warming under the ridge, with temperatures well into the 90s both Friday and Saturday.

This afternoon, CAMs show convection initiating in the general vicinity of the Kansas and Colorado border area, especially south of Interstate 70, by late this afternoon or early evening. Along with a weak disturbance aloft, there may also be convergence along a surface boundary, possibly outflow from a thunderstorm complex ongoing in central and eastern Nebraska. Deep layer shear will be quite strong, 40-50 kts is indicated by the REFS by 03z, as well as moderate to pockets of extreme instability up to 4000 j/kg, concentrated in the area south of Interstate 70. These parameters suggest that convection that develops prior to about 02z will be in an environment supportive of supercells capable of large hail golf ball size or larger, damaging winds and perhaps a tornado. After 02z, the instability rapidly diminishes but with a developing low level jet convection may tend to become more elevated with primarily a lingering large hail risk through about 06z before storms weaken and become isolated. A few additional storms may develop overnight in eastern areas as isentropic lift continues with the low level jet, but they are not likely to be severe with gradually diminishing MUCAPE. Finally, may see some patchy fog develop towards sunrise in the Republican River valley in southwest Nebraska and the Kansas/Nebraska border area.

As noted, the ridge amplifies on Thursday but still west of the Rockies over the Four Corners. Instability peaks at around 01z and is similar to today, moderate to pockets of extreme CAPE up to 4000 j/kg, extending from south of Interstate 70 to most of the area east of Highway 25. Deep layer shear is forecast to be slightly lower compared to today, 30-40 kts, but still sufficient for supercells. Coverage may be quite limited, CAMs show only a handful of updrafts developing, with forcing limited to any weak embedded disturbance rotating around the ridge. However, if something manages to get going it would be capable of large hail, damaging winds, and perhaps a brief tornado. The southwesterly low level jet does develop once again and could maintain the convection through about 06-09z in eastern areas before it weakens.

On Friday, the ridge begins to shift eastward and is located over Colorado by late in the afternoon. Eastern parts of the area will still be susceptible to any embedded disturbance rotating around it in the northwest flow. Similar to previous days, instability will be moderate to pockets of extreme and deep layer shear will be 30-40 kts. Question will be coverage and once again would expect isolated to widely scattered at best in the typical afternoon and evening hours. By Saturday, the ridge will build across the Rockies into the plains, with the axis extending from the Texas panhandle to the Nebraska panhandle. While the northwesterly flow will be pushed east and no longer a factor, southwesterly flow over Colorado on the other side of the ridge will initiate Front Range convection, which will tend to have a northeasterly motion as they make their way across eastern Colorado, with a low chance of reaching far northeast Colorado in the evening and possibly the rest of the area overnight, but likely in a weakened state.

LONG TERM /SUNDAY THROUGH WEDNESDAY/

Issued at 124 PM MDT Wed Aug 19 2026

Starting the extended period Sunday, high pressure is forecast to be situated over the SW CONUS and looks to remain similar placed through the duration of the period. High temperatures in the low to mid 90s that are currently forecast seem reasonable at this time as the 594 dam portion of the high is currently depicted to remain southwest of the forecast area primarily across the SW CONUS. If the high can move a little further east then southwesterly may be able to occur which would raise our temperatures a little more than currently forecast. Winds may be a little breezier as a 15-20 knot 850mb jet is currently forecast to be in place. A lack of 700mb jet brings my doubts to higher wind potential at this time and any wind would mainly sustained.

The position of the high continues to keep the area in northwesterly flow as well through the period allowing for the potential for near daily chances of showers and storms for the most if not all of the area. This patter in notorious for little waves on the eastern periphery of the high to give us storm chances and with guidance currently indicating rainfall potential it does make me cautiously optimistic. However though if that high were to shift a little further east which some ensemble guidance does suggest then that would greatly limit any rainfall potential.Currently based on ensemble qpf data it seems that Tuesday may have the relatively higher potential as guidance is currently depicting a stronger wave coming off of the Rockies.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 423 PM MDT Wed Aug 19 2026

Widely scattered thunderstorms will continue to develop across the area through tonight. Low confidence that either KGLD or KMCK will be directly impacted at this time. Some patchy fog may develop around sunrise Thursday morning with a low probability (around 20%) of brief reductions in visibility at either terminal.

GLD WATCHES/WARNINGS/ADVISORIES

KS...None. CO...None. NE...None.