textproduct: Goodland

KEY MESSAGES

- Red Flag Warning in effect for Kit Carson/Cheyenne counties in CO and Wallace, Greeley and Wichita counties in KS this afternoon.

- Strong NW winds (30-40 mph w/gusts to 55 mph) will develop in the wake of a cold frontal passage early Friday morning.

- Increasing potential for widespread critical fire weather assoc/w breezy WNW to W winds and low humidity Friday afternoon.

UPDATE

Issued at 644 AM MDT Thu Apr 2 2026

Have some concerns on fog, perhaps locally dense redeveloping between 13 and 15Z as winds become a little lighter as we lose the pressure gradient behind the low. Have added fog wording back into the forecast through 15Z. Any fog should should decrease in coverage after 15Z as mixing ensues again.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 400 AM MDT Thu Apr 2 2026

Synoptic Overview: A progressive shortwave and associated mid- latitude cyclone over western KS at 06Z this morning will lift ENE-NE toward the Upper Midwest/Upper Great Lakes today-tonight. Meanwhile, a robust upper level low moving ashore the Pacific Northwest at 06Z this morning will track ESE across the northern Rockies today-tonight then slowly east across South Dakota Fri- Fri night. An associated cyclone developing in the lee of the central Rockies this aft-eve will weaken as it progresses east across central KS (tonight) and eastern KS (Friday).

Today: Modest low-level cold advection in the wake of the departing cyclone will abate from west-to-east late this morning (~12-18Z). At the same time, synoptic subsidence in the wake of the departing upper wave will foster a rapid clearing trend. Low-level southerly return flow will quickly ensue, this afternoon, as the MSLP-850 mb height gradient reorients and tightens in response to surface pressure falls / cyclone development in the lee of the central Rockies. With sunny skies and southerly flow, expect highs ranging from 70-80F, warmest in southern and western portions of the area. A Red Flag Warning is in effect for Kit Carson and Cheyenne counties CO and Wallace, Greeley and Wichita counties KS where current (00Z and 06Z 04/02) operational guidance indicates that SSW to S winds will increase to 20-30 mph w/gusts up to 35-40 mph and RH readings will bottom-out ~15% during the mid to late afternoon. While Red Flag conditions are certainly possible in neighboring areas, namely Yuma County, CO and Sherman and Cheyenne counties in KS, minimum RH readings will increase with northern and eastern extent from the warning area and the onset/duration of breezy S-SW winds will be later/shorter with northern and eastern extent from the warning area.

Tonight-Friday Morning: Southerly winds will weaken this evening as the aforementioned cyclone tracks eastward over/across the Tri-State Area. A short period of strong NNW winds is expected during and immediately following a cold frontal passage a few hours on either side of sunrise Friday morning (~08-12Z in western portions of the area, ~12-16Z in eastern portions of the area) as the eastward advancing cyclone progresses into central KS. 00Z 04/02 GFS and ECMWF forecast soundings indicate ~40-50 knot NNW low-level flow within a shallow (surface to ~3,000 ft AGL) mixed layer immediately following the frontal passage. 00Z 04/02 HRRR and NAM NEST forecast soundings are relatively weaker, indicating ~35-40 knot NNW low-level flow. A rough average of the GFS, ECMWF, HRRR and NAM NEST supports max sustained winds ~30-35 mph and gusts to 50-55 mph. At worst, the GFS solution suggests a potential for 60-65 mph gusts, mainly in NE and E portions of the area (e.g. McCook, Norton, Hill City) where low-level flow is progged to be stronger and vertical mixing may be more robust, i.e. low-level cold advection more likely to overlap with diurnal heating ~12-16Z Fri. For reference, sunrise is ~630 am MDT (1230Z).

Fri-Fri night: Increasing potential for widespread critical fire weather conditions. Expect cooler temperatures in the wake of the front, with highs ranging from the upper 50's (west) to mid 60's (east). Mid-level cloud cover / altocumulus may influence diurnal heating to some extent. Nevertheless, vigorous mixing (up to ~11,000 ft AGL), aided/enhanced by strong mid- level (700-500 mb) cold advection on the southern periphery of an upper level low progressing east across SD during the afternoon, will lead to robust downward momentum transport and considerable drying / deep inverted-V thermodynamic profiles. Guidance indicates ~25-35 knot WNW to W mid-level flow will be present across the majority of the area (strongest in the north) during the afternoon, suggesting sustained winds solidly in the 25-35 mph range (possibly 30-40 mph range in southwest NE) with minimum RH readings ~10-20%, despite cooler temperatures.

LONG TERM /SATURDAY THROUGH WEDNESDAY/

Issued at 308 AM MDT Thu Apr 2 2026

A northwesterly upper-level flow is favored to develop over the forecast area Saturday, replacing a 500-mb trough as it moves northeastward throughout the day. A surface low pressure as an attendant to the trough looks to be located in the Midwest/Great Lakes Region during the morning hours, producing northwesterly to north-northwesterly surface flow across most of the forecast region. Slightly above-average temperatures in the mid to upper-60s are forecast Saturday afternoon, with dry conditions looking to persist. Relative humidities in the mid to upper- teens across portions of Eastern Colorado and Northwest Kansas may implicate critical fire weather conditions as a concern, with wind gusts 25-40 mph in the forecast. Even so, the limiting factor for critical fire weather is the moisture content, as LREF guidance suggests only a 40-50% chance for relative humidities to reach criteria for the hazard in western portions of Cheyenne County Colorado, and even worse chances across the rest of the Tri-State Area. Relative humidities would have to drop a few more points from the current forecast for critical fire weather to be a major concern, which could happen if surface winds have a more westerly, downsloping component during the morning and afternoon hours. Confidence in a Red Flag Warning being needed Saturday afternoon is low, around 5% or less.

The northwesterly upper-level flow looks to be fully established by the evening hours Saturday night, and could last through Monday night. A shortwave trough embedded in this flow is forecast to eject out of Northern Canada and into the United States during this period. Warmer conditions are likely downstream of this shortwave Sunday, with forecast highs currently in the upper-60s to mid-70s. However, as the shortwave begins to traverse the Great Lakes Region, a surface high pressure system moving southeastward out of Canada would introduce cooler air into the Interior United States. A cold front is favored as this process takes place, and is represented in the NBM 75th-25th percentile max temperature spread of 10-15 degrees across portions of the Tri-State Area Monday. Forecast highs Monday afternoon are currently in the mid-60s to mid-70s, though temperatures in the upper-50s to lower-60s cannot be ruled out at this time, especially in Northeastern Colorado and Southwest Nebraska. Dry conditions also look to continue Sunday and Monday, with relative humidities in the mid to upper-teens and upper-teens to 20s respectively. Still, confidence in critical fire weather conditions Sunday and Monday are decreasing, as maximum wind gusts are currently forecast in the 15-20 mph range Sunday, and 25-30 mph range Monday. NBM guidance would support this conclusion, as wind gusts Sunday have at best a 45% chance of reaching critical fire weather criteria in Eastern Colorado, in addition to 90th percentile NBM wind gusts Monday being too weak to overcome relative humidities in the 20s.

Model guidance begins to diverge a bit more on Tuesday as two shortwave troughs enter North America in Western Canada and the U.S. West Coast. However, a split flow is favored overhead through about Tuesday afternoon or evening, which could provide warmer conditions in the upper-60s to mid-70s. Uncertainty regarding high temperatures is still high Tuesday afternoon, as the NBM 75th-25th percentile max temperature spread remains at 10-20 degrees across the CWA. High temperatures would most likely be influenced by how soon a southerly return flow can develop after Monday's cold front, and how soon the incoming shortwave troughs can move in over the forecast area. Some light precipitation is also possible throughout the day Tuesday from this pattern. Precipitation would most likely fall as rain, though wintry precipitation cannot be ruled out during the morning hours when surface temperatures are still near or below freezing. NBM guidance currently suggests about a 25% chance or less for precipitation to occur across most of the forecast region Tuesday. The remainder of the forecast period has a significant amount of uncertainty due to inconsistent timing of the incoming shortwave troughs from the west. However, warmer conditions may be experienced ahead of these systems, with NBM guidance currently suggesting up to a 75% chance for precipitation to occur as these systems traverse the forecast region.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1117 AM MDT Thu Apr 2 2026

VFR conditions are expected to prevail at both KMCK and KGLD through the period. Winds will be the main factor. They will become southeasterly this afternoon, gusting around 20-30 kts. Ahead of a cold front, LLWS at 200 feet AGL from the south will be roaring around 40-50 kts at both sites. A low will be moving over KMCK around 8-10Z, but winds will still be in the 10-20 kts range as winds shift, hence the tempo. Behind the low and cold front, winds from the northwest will increase and gusts up around 40 kts are expected. Some light blowing dust is possible tomorrow during the day.

GLD WATCHES/WARNINGS/ADVISORIES

KS...Red Flag Warning until 8 PM MDT /9 PM CDT/ this evening for KSZ027-041-042. CO...Red Flag Warning until 8 PM MDT this evening for COZ253-254. NE...None.