Area Forecast Discussion
Issued by NWS North Platte, NE
Issued by NWS North Platte, NE
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802 FXUS63 KLBF 262322 AFDLBF Area Forecast Discussion National Weather Service North Platte NE 622 PM CDT Wed Jun 26 2024 .KEY MESSAGES... - A Slight Risk (Level 2 of 5) for severe storms across portions of the Panhandle this evening, as storms forming in Wyoming track east. - An Enhanced Risk (Level 3 of 5) for severe weather on Thursday, mainly along and west of Highway 83. A Slight Risk of severe weather remains in place for the rest of the region on Thursday. Primary severe concerns are large hail and damaging winds, with an increased tornado potential during the evening. - Severe weather chances continue across the region on Friday, with a Marginal Risk (Level 1 of 5) across western and north central Nebraska. - In addition to the severe weather threat, thunderstorms will bring the additional threat of locally heavy rainfall and localized flooding. && .SYNOPSIS... Issued at 320 PM CDT Wed Jun 26 2024 Upper air analysis and satellite imagery indicate a trough over the eastern United States, with a ridge building over the Intermountain West, with an upper level low off the Pacific Northwest. The current pattern places northwesterly flow aloft over western Nebraska. At the surface, a low pressure system is located over south central Kansas this afternoon, with a stationary front extending east and a cold front extending to the west. On satellite, thunderstorms are observed initiating over Wyoming. && .SHORT TERM /THROUGH THURSDAY NIGHT/... Issued at 320 PM CDT Wed Jun 26 2024 A Slight Risk (Level 2 of 5) exists for severe thunderstorms across portions of the Nebraska Panhandle late this afternoon into the evening. Storms are expected to initiate off the Laramie Range this afternoon and track across eastern Wyoming. Potential exists for a bit of storm growth in a narrow corridor of better CAPE across southeast Wyoming and the western Nebraska Panhandle. As storms track into the eastern Panhandle, they will encounter a strongly capped airmass, and are expected to weaken prior to reaching the Sandhills. The primary severe weather concerns this evening will be large hail and damaging wind gusts from storms moving into the region, and primarily before storms weaken. A much stronger severe weather set up is expected for Thursday. Overnight Wednesday, the upper level ridge should progress eastward, setting up an upper level trough over Montana and Wyoming by Thursday afternoon. Ample low and mid level moisture advection is expected over the central plains, with dewpoint temperatures in the 60s. As a deepening low pressure system sets up over Montana and tracks through the Dakotas, storms are expected to initiate along the accompanying surface boundaries in the late afternoon. As storms begin to track towards Nebraska, a southerly low level jet is expected to intensify, which will lead to an increase in low level wind shear. One of the main forecast challenges tomorrow is determining how much surface heating will occur, which will likely impact expected storm modes. If skies can clear allowing better daytime heating, the potential for discrete supercell thunderstorms increases, before storms eventually morph into a linear system. If the daytime heating remains more limited, then a more linear storm mode is likely to prevail. Either way, with ample moisture, sufficient shear, and upper level dynamic support, the Storm Prediction Center has issued an Enhanced Risk (Level 3 of 5) for severe weather across western and north central Nebraska. The Enhanced Risk is mainly for areas along and west of Highway 83, with the rest of the region in an Slight Risk. The main severe weather concerns are large hail and damaging wind gusts, however once the low level jet intensifies, the potential for tornadoes also increases. In addition to the severe weather threat, these storms will be capable of producing locally heavy rainfall. With the strong moisture advection expected ahead of these storms, forecast moisture profiles are quite moist from the surface through the upper levels. Expected PWAT values around 1.3 inches are generally at or above the 90th percentile compared to climatology across western and north central Nebraska. With precipitation mainly falling in thunderstorms, this complicates determining where the heaviest precipitation will occur. In general, expecting rainfall through Friday morning to be one half inch or greater across most of the region, however, locally heavier rainfall amounts are expected. In areas where there has been recently ample rainfall, this may increase the potential for localized flooding. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... Issued at 320 PM CDT Wed Jun 26 2024 Another round of severe weather may remain for Friday, with a Marginal Risk (Level 1 of 5) for severe weather across western and north central Nebraska. At this time, the primary severe weather threat appears to be further east, across southeast Nebraska, Iowa, and Missouri. A lingering risk may remain through the early morning hours, with some guidance suggesting additional redevelopment late Friday afternoon across southwest Nebraska. At this time, the convective mode is a bit uncertain, as well as the primary severe weather concerns. Otherwise, an additional rain chance continues through Saturday morning, with temperatures remaining on the cooler side of climatology through the weekend. Sunday through Monday, upper level ridging is expected to pass over the region, bringing a return to seasonal to above seasonal temperatures. The upper level pattern is currently expected to remain on the more progressive side next week, which should keep moving a series of ridges and troughs. With lower confidence in placement of the upper level pattern, continued with the mean NBM guidance, keeping a slight chance of showers through early week, and generally seasonal temperatures. As guidance gains a better handle on the upper level pattern, should see confidence increase in potential precipitation and temperatures. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 621 PM CDT Wed Jun 26 2024 A developing area of showers and thunderstorms across ern WY will move east through wrn/ncntl Nebraska overnight. Scattered coverage appears likely. This flight concern will be east of the area by 18z Thursday. Another flight concern is the potential for MVFR/local IFR ceilings developing around 12z Thursday morning and lasting until 21z Thursday afternoon. The stratus should develop from south to north Thursday morning and is the result of rapidly increasing low level moisture. Lastly, isolated thunderstorms are possible from 21z Thursday afternoon onward with the best chance across wrn Nebraska, along and west of highway 61. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Richie SHORT TERM...Richie LONG TERM...Richie AVIATION...CDC