textproduct: North Platte

KEY MESSAGES

- Areas of fog, with visibilities down to a quarter mile are likely through mid morning Sunday. There is a small threat for light precipitation tonight in the west with a better threat for showers and thunderstorms in the west Monday afternoon.

- Locally heavy rainfall will be possible Tuesday through Wednesday night. Questions remain on how it will evolve overall, but the remnants of Hurricane Polo from the Pacific could have an impact, potentially producing areas of excessive rainfall. Drier and cooler weather is expected Thursday into the weekend.

SHORT TERM /THROUGH MONDAY NIGHT/

Issued at 141 AM CDT Sun Sep 27 2026

Today through Monday night...Areas of fog will continue across a large portion of the forecast area through mid morning. Winds will shift around to the east then southeast this afternoon as high pressure builds into North Dakota. With the easterly winds, cloud cover may persist in some eastern areas well into the afternoon hours. This will limit highs to around 70. Further west and southwest, highs are expected to reach into the middle to upper 70s with possible low 80s over far SW Nebraska. Readings in SW Nebraska are expected to run slightly cooler than Saturday's as easterly winds and moisture advection will hold back temps. By afternoon, a frontal boundary will become established across the Pine Ridge and far NW Nebraska. A weak disturbance will lift from Wyoming into far western Nebraska and western South Dakota. Am anticipating at least a slight chance for isolated showers and thunderstorms across the far NW forecast area tonight. Feel the best chances are INVOF the frontal boundary, ie. mainly Sheridan County. Overnight, low level winds will shift around to the southeast with the models indicating a high probability of low cloud development overnight. ATTM, the short range model solns and the NBM ensembles only show a weak signal for fog development tonight. That being said, will keep this out of the forecast with this package. With the expected cloud cover, lows will remain mild tonight with readings mainly in the middle to upper 50s. For reference: For North Platte, if you look after August 1st, we still have not hit below 50 degrees for a low temperature. the average date is August 23rd for first occurrence of sub 50 degree lows. The latest sub 50 min temp for North Platte is September 19th. We are currently 8 days beyond that and counting. If September were to end today, it would be the 3rd warmest September on record.

On Monday, upper level flow will transition to more southwesterly, leading to the development of a surface trough over the front ranges of Colorado and Wyoming. After a cloudy start, southerly winds will increase, advecting moisture into the area. By afternoon, forecast PWATs reach 1.20 to 1.40 per the latest NAM12 forecast which is well above the daily climatological max for North Platte. With the cloudy start and abundant low level moisture, highs will reach into the 70s across the area. Showers and thunderstorms will develop during the late afternoon hours across northeastern Colorado and the Cheyenne Ridge. With southwesterly flow aloft, storms will track northeast into western then northwestern portions of the forecast area Monday night. Convection should sustain itself overnight thanks to a nice low level jet which noses north into central Nebraska. The forecast tonight initialized with widespread likely pops across the forecast area and given the latest NAM12 and GFS solns this evening, this appears to be on track.

LONG TERM /TUESDAY THROUGH SATURDAY/

Issued at 141 AM CDT Sun Sep 27 2026

Southwest flow aloft will be in place across the area ahead of the Desert Southwest closed upper low will swing eastward toward the Southern and Central Plains Wednesday. At the same time, the remnants of Hurricane Polo and it's associated tropical moisture, will be pulled northeast and become absorbed into the upper circulation of the upper low by Wednesday. Operational models as well as the Ensemble members of the ECMWF and GFS are starting to focus the potential for heavy rainfall farther to the north impacting western and north central Nebraska.

On Tuesday, the upper low should be located across Arizona. Mid and upper level sub-tropical moisture, with the remnants Hurricane Polo, will be streaming northeastward across New Mexico into Colorado, Kansas and Nebraska ahead of the low. At the surface, low pressure should deepening across eastern Colorado, with an inverted surface trough extending northeastward across southwest into north central Nebraska. The low-levels will also be very moist, with the NAM projecting lower to mid 60s dew points in place. This model is the farther west and focuses some very heavy rainfall amounts near the inverted trough. Other models are not as aggressive, so this will have to be monitored.

Tuesday night into Wednesday, the surface low associated with former Hurricane Polo will track northward across New Mexico and into southeast Colorado by midday Wednesday. This has been supported by last several runs of the ECMWF and the ENS. Heavy rainfall will be associated with this feature, with widespread amounts of 2"+ across much of eastern Colorado into western Kansas. The heavier rainfall has shifted a bit northward into southern Nebraska compared to 24 hrs ago. The latest 27/00Z operational run of the ECMWF is projecting a band of 1-3" of rainfall roughly along I-80 and points south to along the Nebraska/Kansas border. The GFS is now similar, with even heavier amounts. The key will be the northern stream. Trends are for a the northern stream to remain farther north across Montana, through North Dakota and into northern Minnesota. This allows for the tropical rainfall from Polo to shift into southern Nebraska. There will be a rather sharp cut-off to the precipitation on the northern side, so future forecasts will have to be monitored for a better idea of where this cut-off will be. Bottom line is there will be potential for excessive rainfall amounts across a large portions of the region. Some flooding could materialize so future model runs and trends will be monitored carefully.

By Thursday, it appears that the northern stream flow will begin to sag southward and this will focus the heavier rainfall south and east of the area. In addition, a cooler Canadian airmass will sink southward into the region. Mainly dry weather is expected Friday into Saturday.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 1220 PM CDT Sun Sep 27 2026

Visibilities will fall overnight at both the KLBF and KVTN terminals, reaching around a quarter to half a mile at times. Visibilities will be lowest from 09z to 15z Sunday with improving visibilities there after. By late morning into the afternoon hours, expect scattered to broken ceilings around 20000 FT AGL at the KLBF terminal and 2500 to 5000 FT AGL at the KVTN terminal.

LBF WATCHES/WARNINGS/ADVISORIES

Dense Fog Advisory until 10 AM CDT /9 AM MDT/ this morning for NEZ005>010-023>029-035>038-057>059-069>071.