Area Forecast Discussion
Issued by NWS Omaha/Valley, NE
Issued by NWS Omaha/Valley, NE
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253 FXUS63 KOAX 291059 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 559 AM CDT Sat Jun 29 2024 .KEY MESSAGES... - Moderate flooding will continue along the Missouri River into next week for Omaha and points south. - Quiet and cooler for the weekend, with highs in the mid 70s to lower 80s. - A warmer, more active weather pattern is forecast next week with the potential for severe weather and additional flooding. && .DISCUSSION... Issued at 303 AM CDT Sat Jun 29 2024 .Today and Sunday: Widely scattered light showers are ongoing as of 3 AM across portions of northeast NE, and latest CAM data suggest that activity could persist through 7 or 8 AM before dissipating. Otherwise, clouds will diminish this morning as a prominent surface high begins to build into the region from the northwest. The high pressure system, which is strong by early summer standards, will contribute to cooler, drier conditions this weekend. Highs today will be in the mid 70s to low 80s today, and mid to upper 70s on Sunday. Lows tonight will be in the 50s. .Sunday night through Tuesday night: A mid-level trough over the Pacific NW and northern Intermountain region late this weekend is forecast to expand into the north-central U.S. by Tuesday, due in part to a series of perturbations ejecting east from the parent system. The first minor disturbance will move through the northern Plains Sunday night ahead of a stronger secondary system moving through the same area Monday afternoon and evening. A third, more intense disturbance is forecast to traverse the northern Plains and mid MO Valley on Tuesday. At the surface, a warm front extending from a surface low over western SD into central KS Monday morning will develop east through our area Monday afternoon into Monday night ahead of a cool front that will slowly settle south through the area on Monday night into Tuesday night. An unseasonably moist air mass will be advected into the region beginning late Sunday night and continuing into Tuesday by a strengthening low-level jet. In fact, the 28/12z NAEFS indicates 99th percentile to maximum values in mixing ratio, precipitable water, and integrated moisture transport for the model climate for this time of year. That moisture will fuel multiple rounds of showers and thunderstorms during this time period with the potential for severe weather and additional flooding. Shower and thunderstorm chances will increase Sunday night with precipitation likely continuing into Monday morning at some locations. The early-day rain could slow/limit the destabilization process in the vicinity of the warm front moving into the area on Monday afternoon. However, vertical shear will be seasonably strong, and only a sufficient amount of instability will be necessary to support severe storms capable of all hazards Monday afternoon into Monday night. Another round of severe storms appears possible Tuesday afternoon into Tuesday night as the cool front advances south through the area. In addition, heavy rainfall capable of flash flooding will be possible from Monday night into Tuesday night. Runoff from the rainfall could prolong the river flooding in some areas. Highs on Monday are forecast to range from 70s east of the warm front to 80s west of it. Readings on Tuesday are expected to be in the 80s to potentially mid 90s near the KS border. .Wednesday through Friday: By Wednesday, the 29/00z global models suggest that the front will stall across KS and MO before lifting back north on Thursday ahead of a vigorous mid-level trough moving into the northern Plains and mid MO Valley. Needless to say, precipitation chances will continue, as will the potential for heavy rainfall and some severe weather. && .AVIATION /12Z TAFS THROUGH 12Z SUNDAY/... Issued at 541 AM CDT Sat Jun 29 2024 North/northwesterly winds this morning at 5 to 10 knots will veer slightly over the course of the morning to become northerly at 10 to 15 knots at all TAF sites by 17Z. A stray shower will also be possible before 17Z for areas along and west of US-77 (KLNK and KOFK), but the probability is too low to include in TAFs at this time. After 00Z, winds will calm to less than 10 knots and continue slowly veering, becoming more north/northeasterly. VFR conditions are expected to prevail at all TAF sites for the duration of the forecast period. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...Mead AVIATION...Darrah