textproduct: Goodland

KEY MESSAGES

- A Heat Advisory is in effect for southeastern portions of the area where heat index values could reach the mid to upper 100s this afternoon.

- Storm chances continue daily the next few days.

- Best chance for severe weather looks to be on Wednesday. Large hail, damaging wind gusts, and flooding look to be the main threats.

SHORT TERM /THROUGH THURSDAY NIGHT/

Issued at 1202 PM MDT Tue Aug 11 2026

14Z Water vapory imagery and RAP analysis indicated CWA on the northeast periphery of large 594 dm H5 ridge centered just east of the Four Corners area, with stronger flow aloft displaced to the north across the Dakotas into the Great Lakes region. At the surface, fairly weak flow apparent at the surface somewhat obscuring details with main frontal zone near the NE/SD border extending to the southeast into IA.

This afternoon and evening...Strong surface heating, combined with persistent 0-2km convergence across southern zones and in portions of northeast Colorado will bring at least some risk for a few thunderstorms popping up in these areas, although well mixed nature of atmosphere makes available instability in these areas very limited. While more unstable area looks to be capped, could see potential for dry microbursts as DCAPE more than double the available CAPE for much of the area. Low probability for widespread meaningful precipitation in this set up, actually think that there is a better chance to see gusty winds than measurable rain in most locations and will keep PoP's on the low side. Potential for evening storms will roll off the higher terrain and into NW KS and SW NE. Expect this to be disorganized and similar in character to the afternoon threat with gusty winds being the most likely threat. Cold front will begin to sag south into the area overnight, but with dry airmass in place ahead of it and not much forcing behind it do not anticipate much of an impact through the morning hours.

Wednesday-Wednesday Night...Aforementioned cold front will bisect the area during the morning hours and how far south it advances will play a large role on not only temperatures but the thunderstorm impacts as well. Generally prefer the more southerly solutions that line up well with 12Z GEFS mean which would usher in slightly cooler temperatures and likely limit thunderstorm potential to the evening/overnight hours as easterly flow provides instability axis for complex of storms to move into from the higher terrain. The less favored, more northerly position, would shift potential evening precipitation area further north into NE, bring another day of potentially dangerous heat and allow for a few high based/potential dry microburst producing storms near sfc front. In light of favoring the more southerly solutions, think primary weather hazard will be strong outflow winds with MCS as it moves into the area as environment is very favorable for strong cold pools but not sure instability supports a significant hail threat overnight Wednesday.

Thursday-Thursday Night...H5 ridge will have shifted to the southeast with flow aloft becoming southwesterly and axis of ridge centered to the east of the region. With flow aloft more favorable for stronger shortwave impulses, allowing for better afternoon and evening thunderstorm chances than the past week. Speed shear profiles somewhat marginal for organized severe weather, but with decent directional change in the winds any slight increase in the wind fields would produce a more favorable environment for more organized convection. Overall a similar pattern is expected with somewhat moist, easterly flow allowing for thunderstorms to develop near the higher terrain and organize into an MCS as it approaches Tri-State area. Chances for precipitation increase across the whole area, but highest chances will remain along and west of KS/CO border.

LONG TERM /FRIDAY THROUGH TUESDAY/

Issued at 108 PM MDT Tue Aug 11 2026

The long term period starting on Friday morning looks to begin with southwesterly flow over the forecast area at 500-mb, with ridging just to the east and troughing across the Western United States. Several shortwave troughs embedded in the southwesterly flow may impact the forecast area during this time. Ensemble guidance is in good agreement that this pattern is going to last until Sunday morning when ridging builds over the forecast area. However, an upper level trough/low looks to remain across Northern Mexico and the Four-Corners Region for the remainder of the long term period. A surface low in association with this feature would allow southerly flow to continue across the Southern Plains, but meet easterly flow across Kansas, forming a convergence zone.

Overall, the long term period is favored to consist of moist conditions. On Friday and Saturday, shortwave troughs embedded in the upper level southwesterly flow would allow several surface lows to track over the forecast area. Thunderstorms would be favored to form under this pattern. This is supported by NBM 24 hr guidance, which shows over a 40% chance for greater than 0.1 inches of precipitation across nearly the entire forecast region both days, and as high as a 70-90% chance across portions of Eastern Colorado and Dundy County in Southwest Nebraska Friday. Storms are not currently expected to be severe during this period, as LREF guidance suggests less than a 20% chance of seeing sfc-500mb shear greater than 30 kts across most of the forecast area. However, it should be noted that GFS model soundings show an inverted-V profile up to about 3 km, associated with surface dewpoints around 50. This could support microburst potential, where winds could locally reach around 60-70 mph with thunderstorms. However, this is not the favored scenario, as LREF guidance suggests a 60% chance or better that dew points will reach above 60 F across the forecast area. As such, confidence in severe weather occurring Friday or Saturday is less than 5% at this time. High temperatures are currently forecast in the 80s and lower 90s both Friday and Saturday.

As ridging builds in overhead Sunday and troughing develops across the Four-Corners Region, conditions may start to dry out, as forecast relative humidities (RH) drop from the 50s and 60s on Sunday to the 30s and 40s on Tuesday. This would be driven by a low to the southwest of the forecast area injecting hot, dry air into the incoming southerly flow. Conditions look to remain moist enough for thunderstorm activity to continue Sunday through Tuesday, but it is a point to keep in mind that drier conditions may be coming toward the middle of next week. As for thunderstorm activity during this period, it would be driven by southerly flow meeting easterly flow in Kansas, creating convergence in this zone. Again, LREF guidance is in support of thunderstorms remaining non-severe, showing less than a 20% chance for wind shear greater than 30 kts across most of the forecast region all three days. If hotter and drier conditions can indeed develop, microburst potential may become more of a concern. However, at this range, there is not enough confidence to say that microbursts are likely. This will be another development to watch as we go into next week. High temperatures are forecast in the 80s Sunday and Monday, and then the upper 80s and lower 90s on Tuesday.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 1053 AM MDT Tue Aug 11 2026

VFR conditions and light winds will prevail through most of the period before a cold front slowly advances shifting winds to the ENE after 12Z. A few thunderstorms are possible, especially after 00Z could bring a brief period of strong and erratic winds with very high cloud bases. Coverage will be on the low side with chances of storms impacting either TAF site being 10 percent or less.

GLD WATCHES/WARNINGS/ADVISORIES

KS...Heat Advisory until 8 PM MDT /9 PM CDT/ this evening for KSZ003-004-014>016-027>029-041-042. CO...None. NE...None.