Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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000 FXUS63 KOAX 240845 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 345 AM CDT Fri Mar 24 2017 .SHORT TERM...
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(today through Sunday) Issued at 345 AM CDT Fri Mar 24 2017 Intense mid-level cyclone associated with 150 m H5 height falls this evening was located over SE CO early this morning. Broad zone of ascent associated with strong low- to mid-level thermal advection was ongoing to the northeast of the cyclone from the central Plains to the upper MS river valley. The ongoing forcing for ascent is expected to weaken this morning as the mid-level dry slot works northeast toward the area. We will continue with some high pops initially in the northwest CWA close to the mid-level deformation zone as well in the southeast CWA associated with ascent with the veering low-level jet. Models are in fair agreement today in the upper level cyclone moving east across southern KS/northern OK and into eastern MO by Saturday night. As the dry slot works into the southern CWA the 700-500 mb lapse rates will steepen as 500 mb cold pocket works toward the southern CWA. This will combine with existing low- level moisture to increase instability in a zone from the 850 mb front south into KS/MO. As temperatures ahead of the cold front increase to around 70, and forced ascent associated with 700-400 CDPVA becomes juxtaposed over the southern CWA we will likely see isolated to scattered convection develop. Instability is fairly weak for late March and the wind profile is not overly favorable for severe, but some small hail appears possible given the cold temperatures aloft. Otherwise we expect frontogenesis to increase over the northwest CWA within the developing deformation zone where steady light to moderate rainfall is expected. The deformation band will further expand and include a good part of the rest of the CWA tonight and into most of Saturday before shifting east with a dry Sunday expected. Temperatures today are problematic with outflow associated with the ongoing convection now pushing south of I80. We are still observing 2-3 mb 3-hr pressure rises behind this outflow and thus it may continue to push south a bit before stalling. There will be a strong temperature contrast across this boundary today somewhere in the CWA with highs near or slight better than 70 to the south of it and highs in the 40s in the northwest CWA. This boundary should push to the south tonight with much cooler air expected into the weekend. .LONG TERM...(Sunday night through Thursday) Issued at 345 AM CDT Fri Mar 24 2017 The active weather appears to continue into the extended range of the forecast. Another trough crossing the Plains on Sunday night into Monday will bring a chance of rainfall to mainly the southern CWA. After another short break another trough is expected toward mid week, but models diverge significantly on the track of this system with the GFS well south while the EC is much farther north. Given these differences we will continue with some pops for mid week with continued below normal temperatures.
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&& .AVIATION...(For the 06Z TAFS through 06Z Friday night) Issued at 1213 AM CDT Fri Mar 24 2017 The cold front is through KOFK and MVFR and IFR ceilings will start to impact the terminal by 10Z this morning, and should continue through the end of the period. The cold front will move through KOMA/KLNK by 18-20Z with the MVFR/IFR cigs to follow by late afternoon. We will also see period of rain overnight and through the day at KOFK. Although isolated showers are possible overnight tonight at KOMA/KLNK, more steady rainfall will not develop in these area until late Friday afternoon into Friday evening. Although some thunder is possible Friday afternoon at KOMA/KLNK, it appears that the chances are to low to currently include in the TAFs. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ SHORT TERM...Boustead LONG TERM...Boustead AVIATION...Boustead is the U.S. government's official web portal to all federal, state and local government web resources and services.