textproduct: North Platte

KEY MESSAGES

- There is a good chance for moderate to heavy rain tonight over the eastern Nebraska Panhandle and northwestern Sandhills.

- Precipitation chances will continue through the weekend with chances Friday night, Saturday night and Sunday night. Heavy rain will be possible Saturday night.

- Precipitation chances will continue into next week as southwesterly flow aloft persists across the Central Plains

SYNOPSIS

Issued at 309 PM CDT Thu Sep 17 2026

H5 pattern this morning had high pressure located over the Mississippi Delta region. Upper level low pressure was located over far northeastern Manitoba and northwestern Ontario. A trough extended south of this feature to Lake Superior. Further west, low pressure was located over northern California. Upstream of this feature, high pressure was located approximately 600 miles off the northern Oregon coast. Downstream of the California low and west of the Mississippi Delta high, embedded disturbances extended from the Four Corners into southern Wyoming. The latter feature, has led to a broad area of showers across eastern Wyoming and the Nebraska Panhandle. At the surface this afternoon, a warm front extended roughly from around Grant Nebraska to just south of McCook Nebraska. North of the front, winds were easterly wind readings ranged from around 70 in northern Nebraska to the upper 70s to near 80 along I- 80 to the mid and upper 80s over far SW Nebraska. Further south into northwestern Kansas, readings were in the lower 90s. Skies were partly to mostly cloudy and a broad shield of showers and embedded thunderstorms was impacting Sheridan and the western half of Cherry County.

SHORT TERM /THROUGH FRIDAY NIGHT/

Issued at 309 PM CDT Thu Sep 17 2026

Precipitation chances, the threat for heavy rain and the potential for a strong storm or two are the main forecast challenges in the near term. The short range model solutions this morning including the NAM12 and GFS solns have failed to initialize with the ongoing precipitation across the northern half of the panhandle. The HRRR has trended toward more "reality" with the past couple of runs finally showing the ongoing pcpn in the northern panhandle. Going forward this evening, there are two areas being monitored closely for thunderstorms. The first area is INVOF the warm front just off to the south of the I-80 corridor. The latest HRRR soln has this feature roughly along a line from Grant to near McCook at 21z this afternoon. Already south of the front, readings were well into the lower 90s this afternoon. This has pushed SB CAPES to 1500 to 2500 J/KG this afternoon along the frontal boundary. Shear, especially in the warm sector over western Kansas remains weak this afternoon. Once you approach the front, deep layer shear approaches 30 KTS and there is some indication of low level helicity (ie. 100 M2S2 in the 0-1km agl layer). If storms can form, and that's if...there would be some potential for stronger storms INVOF the front. This area will need some close monitoring over the next 2 to 4 hours. The other area that has a really good chance for precipitation tonight is over the panhandle into the northwestern Sandhills. Current satellite imagery has a mid level disturbance lifting over northeastern Wyoming with a secondary disturbance over central Colorado. As this feature lifts into northern Colorado this evening and eastern Wyoming overnight, the models develop a broad shield of moderate to heavy rain across the panhandle into NW Nebraska. For our forecast area, the latest NBM ensembles have a 70 to 100 percent chance of exceeding 0.25 inches of precipitation tonight north of a line from Oshkosh to Springview. When that threshold is raised to 0.50 inches the probabilities only fall off to 60 to 90 percent. National guidance has a slight risk for excessive rainfall tonight over far northwestern portions of the forecast area with a marginal risk north of highway 92. This risk is supported by very high forecast pwats across the area. The latest NAM soln has PWATS at 18z this afternoon of 1.55" for LBF. Our 18z RAOB came in with 1.80". This mark is well above the climatological max for the 2nd week of September. Also forecast soundings across the western Sandhills tonight have a nice skinny CAPE profile. As for a flash flooding risk. Based on the location of lowest FFG, the risk is greatest over the Pine Ridge of northern Sheridan County and possibly over southwestern Garden and Deuel counties. Three hr FFG in these areas are generally between 1.75 and 2.25 inches. This guidance quickly rises into the western and northwestern Sandhills where 3 hr FFG is well over 4 inches. Given the relative lack of rainfall over the past few months in the panhandle, and with the latest hi res solns having the highest QPF along a corridor from northern Garden County, northeast to well east of the Pine Ridge over NW Cherry County, will forgo a flood watch ATTM.

In the wake of exiting precipitation Friday morning, a moisture boundary will become established from SW Nebraska into NE Nebraska Friday afternoon. Convection is forecast to develop along and east of this boundary Friday afternoon and should remain east of the forecast area. Most of the forecast area will lie west of the moisture boundary and south of an approaching cold front Friday afternoon. This will allow highs to reach the mid and upper 80s for most of the forecast area. The exception will be over northwestern Nebraska where earlier frontal timing will lead to highs in the upper 70s.

By Friday night, a lead shortwave will track from NE Colorado into western Nebraska, initiating showers and thunderstorms Friday evening. Southwesterly flow aloft, will carry this activity northeast overnight, bisecting the forecast area from SW into NE Nebraska.

LONG TERM /SATURDAY THROUGH THURSDAY/

Issued at 309 PM CDT Thu Sep 17 2026

In the wake of the exiting system Friday night, Saturday will feature chance pops, although forecast QPF will be light at best. Northeasterly winds, and cloud cover will limit highs to the upper 60s to middle 70s for most areas. By Saturday night persistent upper level low pressure will approach western, then central Wyoming by 12z Sunday. A lead disturbance, will lead to a decent chance for precipitation Saturday night into Sunday morning. ATTM the greatest threat appears across western into southwestern portions of the forecast area. The upper level low will migrate from central Wyoming into South Dakota Sunday into Sunday night bringing another threat for showers and thunderstorms to the forecast area. As this system exits into the upper Mississippi Valley Monday, a second low and trough of low pressure aloft, will lift from southern California into the intermountain west Tuesday. Downstream of this feature, there will be a continued chance for showers and thunderstorms Monday through Wednesday. The trough is progged to clear the forecast area Wednesday night with lower precipitation chances expected for Thursday. Highs early next week will be in the 60s, with a return to 70s mid week.

AVIATION /18Z TAFS THROUGH 18Z FRIDAY/

Issued at 1153 AM CDT Thu Sep 17 2026

For the KLBF terminal: Expect broken ceilings this afternoon around 10000 FT AGL. By 00z Friday, isolated thunderstorms may develop INVOF a warm front which will be located just off to the south of the terminal. Given the uncertainties as to this coming to fruition, will handle this mention with a prob30 group from 01z through 05z Friday. Overnight into Friday morning, expect mainly cloudy skies will ceilings transitioning from 7000 FT AGL to 20000 FT AGL. For the KVTN terminal: Expect broken ceilings around 10000 FT AGL to persist through early evening. Cloud decks will fall to 1000 to 1500 FT AGL mid evening with a good chance for thunderstorms. Will handle the mention with a tempo group from 03z to 07z. Ceilings may lift with passage of storms to 2500 FT AGL during this time frame. Ceilings will then lower to around 500 FT AGL overnight, lifting to around 1200 FT AGL late morning Friday.

LBF WATCHES/WARNINGS/ADVISORIES

None.