textproduct: Goodland

KEY MESSAGES

- Severe weather potential this evening is decreasing. If current trends persist, Severe Thunderstorm Watch 613 will be cancelled prior to 07Z.

- Weekend precipitation chances mainly at night with showers and storms moving out of Colorado. Severe chances will be low with this activity.

- Heat peaks today, then slightly cooler over the weekend.

UPDATE

Issued at 900 PM MDT Fri Aug 21 2026

SVR Watch 613 is in effect for a limited portion of the area (west and north of Goodland) until 07Z. Radar/observational trends suggest that severe weather potential in the watch area may largely be tied to a long-lived supercell currently (at 03Z) progressing southward from the Nebraska Panhandle into northeast Colorado. Right-mover motion this evening is from the NNE. From a persistence standpoint, -if- the aforementioned supercell remains discrete, it's present course suggests that it would remain west of Yuma and Kit Carson counties in CO.. and that severe weather potential in the Goodland CWA may be contingent upon additional convective development. In a weak forcing regime, additional convective development will likely be a function of mesoscale forcing, e.g. an MCV emanating from ongoing long-lived convection. Bottom line, there is very low confidence in convective development/evolution over the next several hours.

SHORT TERM /THROUGH MONDAY NIGHT/

Issued at 1230 PM MDT Fri Aug 21 2026

Northwest flow continues today around a ridge centered near the Four Corners. Weak to moderate instability is building in the area with 40-50 kts of deep layer shear. Models have struggled in this pattern with the convection, and will probably do so once again today, with a wide range of solutions offered by the 12z CAMs. They are missing some of the mesoscale features which ultimately play an important role, such as the outflow boundary which is moving through areas north of I-70 originating from morning convection in Nebraska. While confidence is low in the details, generally expect to see isolated to widely scattered thunderstorms develop this afternoon north of Interstate 70. A supercell will be possible given the environmental parameters, capable of large hail, damaging winds and a brief tornado. Another cluster of storms may move across the area this evening, originating in southeast Wyoming and sustained by a strengthening low level jet. If those storms develop and cluster, may see another risk of damaging winds similar to last night. Overnight, the low level jet remains active with isentropic lift maximized over eastern parts of the area (east of Highway 25). May see elevated storms develop late near or just east of the area with a marginal wind and hail threat as MUCAPE lingers at 1000-1500 j/kg. Outflow from those storms will push a cold front through the area around 12z with winds shifting to the east and briefly gusty. May see patchy fog develop along the leading edge of the front as well, mainly in the Colorado/Kansas border area, but it would be transient.

On Saturday the upper ridge axis will run from eastern Wyoming and Colorado to the Texas panhandle. Convection will develop in the afternoon over the Rockies and Front Range with the southwest flow, then move across the eastern plains and spreading into the area Saturday night. With the later arrival, probably not until after 03z, storms will be weakening but may still pose a marginal risk for damaging wind gusts as they make their way across the area through the overnight.

The ridge flattens out on Sunday and extends from the Four Corners to the Texas panhandle. Zonal flow over the top through northern Colorado will initiate convection over the mountains and Front Range, and once again make the trek across the plains and into the area Sunday night. These will arrive slightly earlier, 00-02z, in far northeast Colorado and may still pose a marginal wind and hail threat, but with only weak instability forecast and deep layer shear around 20 kts, severe chances will be low. Storms will gradually weaken as they move east into the remainder of the area Sunday evening.

The ridge strengthens a bit on Monday with height rises in Colorado, and the zonal flow is through southern Wyoming. Forecast instability is weak and generally less than 1000 j/kg, though deep layer shear does increase to around 40 kts. RFS suggests a few scattered storms developing, moving east and then southeast with the mean flow Monday afternoon and evening in areas generally north of Interstate 70 with perhaps a marginal risk for wind and hail.

The temperature trend for the period will be near to slightly above normal through the weekend, then above normal on Monday with temperatures currently forecast in the mid to upper 90s.

LONG TERM /TUESDAY THROUGH FRIDAY/

Issued at 202 PM MDT Fri Aug 21 2026

Synoptically, a ridge is forecast to be over the SW CONUS and currently looks to remain relatively stationary. Throughout the week, there appears to be a few shortwaves moving though the CWA, which may bring higher precipitation chances.

High temperatures for the week are forecast to be in the 90s for the majority of the area. The "coolest" day for the period looks to be Wednesday, with highs in the mid 80s to low 90s, whereas Friday looks to be the hottest with highs in the mid 90s. If the ridge begins to amplify or move eastward, as guidance hints, higher temperatures could be seen. Winds throughout the week are forecast to be calm to breezy, and relative humidity values are expected to be higher than 30%, which should help minimize fire weather concerns.

Precipitation chances are present during the week. As some shortwaves move around the high, they will likely to be our main precipitation producers. The day currently with the highest precipitation chances is Tuesday. Guidance hints at some vorticity associated with the shortwave as it moves through Tuesday afternoon. Both CAPE and shear appear sufficient for severe storms; however, some guidance indicates a mismatch between higher/lower CAPE and lower/higher shear, which could lead to less organized storms. Looking at qpf, some guidance shows the possibility of heavy rainfall with these storms, which is something to keep in mind as we get closer to Tuesday. The rest of the week there is roughly a 15-30% chance of PoPs as various shortwaves move through the region.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 1100 PM MDT Fri Aug 21 2026

GLD: Aside from a potential for sub-VFR ceilings or fog an hour or two on either side of sunrise, VFR conditions will prevail through the 06Z TAF period. Breezy (20-30 knot) NE winds associated with convective outflow will affect the Goodland terminal for an hour or two at the beginning of the 06Z TAF period. Otherwise, light northeasterly or variable winds will prevail through sunrise, becoming ESE or SE and increasing to 10-15 knots during the late morning and persisting through the afternoon.

MCK: Aside from a potential for sub-VFR ceilings or fog an hour or two on either side of sunrise, VFR conditions will prevail through the 06Z TAF period. Light northeasterly or variable winds will prevail through sunrise, becoming ESE or SE and increasing to 10-15 knots during the late morning and persisting through the afternoon.

GLD WATCHES/WARNINGS/ADVISORIES

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