Area Forecast Discussion
Issued by NWS North Platte, NE
Issued by NWS North Platte, NE
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431 FXUS63 KLBF 182346 AFDLBF Area Forecast Discussion National Weather Service North Platte NE 646 PM CDT Tue Jun 18 2024 .KEY MESSAGES... - Cool conditions on Wednesday with high temperatures 10 to 20 degrees below seasonal values. However, temperatures quickly rebound back into the 80s for the remainder of the week into the weekend. - Near daily shower and thunderstorm chances continue across the area each day through the rest of the week into the weekend. The severe threat remains uncertain at this time. && .SYNOPSIS... Issued at 206 PM CDT Tue Jun 18 2024 Recent GOES-16 WV and RAP 500-mb analysis showed a dome of high pressure centered over the east coast with a ridge extending north- northeastward into northern Quebec. Southwest flow aloft continues across the region as an upper-level trough swings across the northern Plains. At the surface, low pressure was moving northeastward out of eastern South Dakota into Minnesota. An attendant cold front extended southwest into eastern Nebraska and central Kansas to another area of low pressure centered over southwestern Kansas. This front advanced through western and north central Nebraska this morning allowing the strong overnight winds to subside some and shift towards the northwest. At 2 PM CT, temperatures ranged from 61 degrees at O`Neill to 76 degrees at Imperial. The aforementioned cold front has sagged a bit further to the southeast than previously thought with convection initiating along the boundary in our eastern neighbor`s CWA. This ongoing development is occurring south and east of the local area and should continue to move north and east as the afternoon and evening progresses. The potential for a brief shower or thunderstorm exists across far north central Nebraska, generally areas east of Highway 183. Do believe the bulk of the severe threat will reside outside of these areas, though cannot rule out some hail or gusty winds should a stronger storm develop and maintain itself. Anything that does develop should exit the previously mentioned areas by 00Z this evening. && .SHORT TERM /THROUGH WEDNESDAY NIGHT/... Issued at 206 PM CDT Tue Jun 18 2024 Tonight... Thanks to the cold frontal passage, overnight lows will cool back into the 40s and 50s across western and north central Nebraska. Clouds will continue to back build over the region late tonight with relatively light winds out of the north and east as surface high pressure nudges south out of Montana. A shortwave embedded in the flow aloft combined with outflow from the storms to the south should be enough to trigger scattered showers and non-severe thunderstorms to develop after 06Z across southwest into portions of central Nebraska. Wednesday and Wednesday Night... The activity from overnight is expected to wane across the area through Wednesday morning with a cloudy and cool day is in store for the area. High temperatures will be in the mid 60s which is 10 to 20 degrees below normal for mid-June. An upper-level shortwave ejecting out of the central Rockies Wednesday evening will provide another focus for showers and thunderstorms to develop, continuing overnight. Given the cloud cover and cool temperatures, instability will be meager (MLCAPE 300 to 500 J/Kg) with weak deep-layer shear (20 to 30kt), thus anticipate non-severe thunderstorms with this activity. These showers and thunderstorms should bring some moisture to portions of southwest and north central Nebraska, though generally 0.25 to 0.75" appears most likely. Locally higher amounts up to 1"+ may be observed for areas generally east of Highway 83. && .LONG TERM /THURSDAY THROUGH TUESDAY/... Issued at 206 PM CDT Tue Jun 18 2024 Thursday... Showers and thunderstorms are expected to linger into Thursday morning, waning through the afternoon hours. Another upper- level shortwave ejecting eastward out of Wyoming and Colorado will provide a focus for isolated to scattered thunderstorms across the Nebraska Panhandle Thursday afternoon and evening. Mid-level warm air advection (WAA) will result in a capping inversion and when combined with persistent cloud cover, convection may be limited Thursday. With the position of a lee trough near the Colorado/Wyoming border, southeasterly surface flow will increase, helping amplify southeasterly low-level flow and moisture advection across the area. In fact, both the NAEFS and ENS guidance highlighting precipitable water (PWAT) values approaching the 99th climatological percentile, especially north of a warm front expected to lift northward across the Panhandle into the Sandhills. Despite this, details remain rather murky resulting in uncertainty on the degree of the severe risk Thursday given large spread amongst model guidance. Will continue to monitor the severe potential during this period as CAMs get into this time range. Friday and beyond...The cool conditions felt on Wednesday will be short-lived as temperatures warm back into the 80s as the upper- level ridge retrogrades westward into the weekend. Continued southwesterly flow aloft with additional northern stream disturbances tracking across the region will keep the extended forecast in a relatively active pattern. While recurring afternoon and evening thunderstorm chances exists in the extended, the degree of severe potential and coverage remains in question. A return to above normal temperatures and drier conditions will be felt heading into early next week as the upper-level ridge re-amplifies across the Desert Southwest, extending north into the northern Plains. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 641 PM CDT Tue Jun 18 2024 VFR conditions are expected over the next 24 hours. Winds will diminish this evening out of the north to northeast around 10 to 15 kts. There is a chance for rain to move in during the afternoon hours, but at this time coverage remains uncertain, thus have left the mention out of the tafs at this time. && .LBF WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Viken SHORT TERM...Viken LONG TERM...Viken AVIATION...Gomez