textproduct: Goodland

KEY MESSAGES

- Breezy SE to SW winds expected across portions of the area Sunday evening into Monday with sustained winds of ~20-25 mph may gust to 40 mph

- Scattered storms possible Monday afternoon-evening. A severe storm capable of producing brief, localized wind gusts up to 65 mph and large hail cannot be ruled out, mainly east and south of Colby, KS.

- An early morning cold frontal passage will bring much cooler temperatures to the area Tue-Tue night. Wed morning lows may dip into the upper 40's in eastern CO and adjacent KS-NE border counties.

SHORT TERM /THROUGH TUESDAY NIGHT/

Issued at 128 PM MDT Sun Sep 13 2026

The upper level ridge axis is making it's way across the High Plains today ahead of a strengthening area of low pressure over the Pacific Northwest. At the surface, a surface trough is gradually extending south over the High Plains from an area of low pressure over Wyoming and Montana. On Monday, the Tri-State area should be under southwest flow aloft as the upper level low moves along the Canadian border with Eastern Montana and North Dakota towards Lake Manitoba. This will bring our next cold front and precipitation chances to the area as we start the week.

So far today the forecast for the stratus has panned out as we see it burn off from the west and south. The big question is whether or not our northwest corner of counties will see clearing skies or if they stay socked in with low ceilings through the overnight hours. SREF guidance is favoring the stratus lingering this afternoon and once again expanding southeast across the area this evening and into the overnight hours. Patchy fog could also occur in the early to late morning hours Monday along the Kansas/Nebraska border.

This afternoon winds will begin to pick up with southeast winds of 20-25 mph and gusts up to 40 mph possible over the area. The strongest winds are currently expected to occur over Eastern Colorado as we see a tightening of the 850 mb height gradient within the eastern edge of the lee surface trough. The breezy winds could linger into Monday with winds becoming southwesterly around sunrise before decreasing to 10-15 mph with gusts up to 30 mph possible through the afternoon tomorrow.

CAM guidance has been fairly consistent over the last 24 hours in regards to the development of showers/storms Monday afternoon. Some CAMs like the HRRR and RAP are trying to have scattered showers during the late morning to early afternoon, but confidence is currently low (less than 20%). The middle of the afternoon into the evening is where I am feeling more confidence at 50-60% for storms to develop. So far, it has been consistent in the models for isolated convection to develop along a convergence boundary over the eastern half of the area. Model soundings continue to favor an inverted-V profile with 1,500-2,300 J/kg of Surface and Mixed-Layer CAPE when there are not showers earlier in the day. With favorable lapse rates and shear of 35-50 kts, we could see large hail and damaging winds gusts up to 65 mph as the primary concern. We could still see two areas for initiation impact the CWA. The first could be over portions of Western Kansas possibly along the convergence boundary and another over Eastern Colorado closer to the late afternoon/evening hours. In models with the morning shower activity, the CAPE generally lowers below 1,000 J/kg with 0-6 km shear and effective shear of 25-30 kts. Any severe weather should taper down in the late evening/early overnight hours. However, as a cold front moves into the area late Monday into Tuesday morning we could see more showers and sub-severe storms linger over the Tri-State area. 12Z guidance has the front potentially stalling around our southern CWA border Tuesday, which could lead to more showers and generally sub-severe storms on Tuesday, especially over the eastern and southern portions of the area.

LONG TERM /WEDNESDAY THROUGH SUNDAY/

Issued at 204 PM MDT Sun Sep 13 2026

Wednesday morning, ensembles are favoring a strong 500-mb high across the Southeastern United States, with troughing to the west. At the same time, a strong surface high supported by an active jet stream looks to be located in the Great Lakes Region. These features are favored to remain in place through Friday. Southerly flow would be expected across the Great Plains between the southeastern high and western trough, however the surface high in the Great Lakes Region is forecast to support easterly surface flow across Kansas. Warm, wet conditions look to be in place across the area Wednesday through Friday as a result of this pattern. High temperatures all three days are in the upper 70s to mid 80s. It's important to note that NBM 75th percentile and higher scenarios show highs in the upper 80s to lower 90s Thursday and Friday. This could occur if the southerly flow can reach further north into Southern Nebraska, or if solar heating can develop. Even so, rain is in the forecast, as NBM 24 hr precipitation guidance shows a 40% chance or greater of receiving more than 0.1 inches of rain both Wednesday and Thursday across most of the forecast area. These probabilities are highest along a line from Norton, KS to Tribune, KS Wednesday (50-70%), and in Northeastern Colorado and far Southwestern Nebraska Thursday (60- 75%). Most of this activity is forecast to be widespread rain rather than localized convective storms, the exception being Wednesday. LREF guidance suggests a 40-55% chance across most of the forecast area of experiencing surface CAPE (a measure of atmospheric instability) greater than 1000 J/kg Wednesday evening. Some higher end scenarios (90th percentile and greater) show CAPE may rise above 2000 J/kg. Even so, this convective activity is not favored to be severe, as GFS and EC soundings show sfc-6km shear remaining below 30 kts during the afternoon and evening hours. Confidence in severe weather occurring Wednesday is 5% or less.

The forecast begins to become a bit more uncertain by Saturday morning, specifically regarding the trough to the west of the forecast area. This feature is expected to be moving slowly eastward throughout the long term period, though guidance is inconsistent on when it will move over the forecast area. However, once it moves over the area, temperatures may drop a bit more, in addition to precipitation chances. This is represented in the forecast temperatures for both Saturday and Sunday, with highs in the mid to upper 70s. Additionally, NBM 24 hr precipitation guidance drops the probabilities for greater than 0.1 inches of rain below 40% on Sunday. These probabilities are a little higher on Saturday, but is likely due to a higher chance that the trough is still west of the forecast area on Saturday. In other words, conditions similar to Wednesday through Friday are expected as long as the trough stays to the west of the forecast area. However, once it moves in over the region, temperatures and precipitation would likely drop off a little bit.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/

Issued at 600 PM MDT Sun Sep 13 2026

KGLD: Current conditions are VFR, however stratus is expected to develop over the airport by 03Z, producing MVFR ceilings. There are indications that fog may develop along with this stratus between 04 and 08Z. However, considering stratus will be in place, there is not enough confidence to include it in the TAF, especially since recent observations still show relative humidity in the mid to upper 50s. Additionally, a low level jet is expected to develop, producing moderate wind shear over the airport overnight and into the morning hours. Conditions are expected to return to VFR around 07Z as the cloud deck lifts. Thunderstorms are possible between 21 and 24Z the 14th, but VFR conditions are expected otherwise.

KMCK: Guidance indicates that stratus is expected to rapidly redevelop over the airport by 01Z, quickly lowering conditions into IFR. There are fog indications for KMCK as well, though the development of stratus would prevent significant radiational cooling to create the fog. A low level jet could produce some wind shear at the airport between 12 and 15Z, though there is currently not enough confidence to include in the TAF. Thunderstorms are also possible at KMCK between 22 and 24Z the 14th, but VFR conditions are expected to prevail from 14Z through the end of the period.

GLD WATCHES/WARNINGS/ADVISORIES

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