Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

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685 FXUS63 KOAX 051725 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 1125 AM CST Mon Dec 5 2016 .SHORT TERM...(today through Wednesday) Issued at 244 AM CST Mon Dec 5 2016 Latest water vapor imagery in combination with RAP 500mb analysis shows fast and nearly zonal flow over the region with a potent shortwave trough digging across north central Montana. At the surface, a broad area of low pressure over the northern High Plains continues to move east ahead of the upper shortwave. All eyes are on associated cold front behind this system which will be our biggest weather story of the week. For today, strong southwesterly 850mb flow ahead of the previously mentioned system should allow highs to warm into the upper 40s to lower 50s despite increasing cloud cover. The front will drop through the Dakotas today, reaching our northwestern counties by mid/late afternoon. A few scattered sprinkles/flurries across our northeastern CWA can`t be ruled out as the front dives into the region with gusty northwest winds behind the front. The above mentioned shortwave trough will deepen and close as it moves across the Northern Plains allowing continued cold air advection to ooze south into the Central Plains. A quick moving shortwave currently off the Pacific Northwest coast will drop southeast toward the forecast area late Tuesday into Wednesday. Model guidance continues to vary in regards to whether the strongest associated forcing for ascent occurs primarily over Kansas like the GFS and NAM or near the KS/NE border like the ECMWF. Our model blends continue to go with a middle of the road solution but confidence in any snowfall north of I-80 is fairly low. Storm total snowfall grids give the KS/NE border the highest accumulations of around an inch. The anticipated strong Arctic surge will follow this trough into the end of the week as a 1040mb surface high builds in from the Northern Plains. .LONG TERM...(Wednesday night through Sunday) Issued at 244 AM CST Mon Dec 5 2016 First Arctic airmass of the season lingers over the area through Thursday with the high pressure ridge overhead by Friday morning, This should be our coldest morning of the season with lows dropping into the single digits for all areas. Strong return flow will set up by early Friday bringing strong warm air advection into the region. The models diverge again with the GFS developing pcpn across the area near a strong warm front while the ECMWF keeps this frontal boundary north of us. Forecast blends put some small pops in our northern counties which seems reasonable at this point. Temperatures over the weekend will be closer to normal with highs in the low 30s and lows in the low 20s. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) Issued at 1123 AM CST Mon Dec 5 2016 VFR conditions are expected through the afternoon. A strong cold front will move through all 3 TAF sites this evening switching winds to the northwest, and increasing overnight with some gusts likely. We will include a period of MVFR cigs for KOMA during the evening along the front as well as a short period of some light showers or sprinkles. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ SHORT TERM...Kern LONG TERM...Kern AVIATION...

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