Area Forecast Discussion
Issued by NWS Omaha/Valley, NE

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS63 KOAX 221726 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 1226 PM CDT MON AUG 22 2016 .SHORT TERM...(today through Wednesday) Issued at 331 AM CDT MON AUG 22 2016 Quiet weather today, but strong and possibly severe storms are possible Tuesday afternoon evening. Latest satellite imagery has shown an accas cloud field developing from near Fremont northeastward into northwest IA. Hires CAMs suggest that a few sprinkles could develop there this morning, but would be just northeast of our forecast area. Otherwise, the story for today is increasing temperatures and breezy to windy conditions developing, with speeds from 15 to 30 mph, and gusts 30 to 35 mph in northeast NE. Highs will be warmer than yesterday, reaching the mid 80s to upper 80s mostly, but could reach around 90 along the NE/SD border region. Southerly breezy winds continue overnight, but it should remain dry, in advance of the trough currently moving through the 4-corners region. Low temps tonight should be back above normal in the mid 60s. Low level moisture will continue to deepen Tuesday on continued southerly flow ahead of the upstream trough and cold front that moves in Tuesday night. Tuesday morning should remain dry, but storm chances increase by Tuesday afternoon when the cap eventually breaks. By then, dewpoints will probably be in the upper 60s to lower 70s, with available CAPE from 2000-3000 J/kg. 0-6km bulk shear values are 30-40 knots, thus sufficient parameters are coming together for a slight risk of severe storms across the area, which will continue into the evening hours. Wind and hail will the be the primary threat initially, although there are some indications that a warm frontal boundary could develop that extends eastward from the surface low, which could set up somewhere along or just north of I80. It could also just be an outflow boundary reinforced by convection. Either way, if this indeed develops, isolated tornadoes may occur in northeast NE and northwest IA, although certainly too far out to pinpoint at this time. Another threat with storms Tuesday will be potential heavy rains just north of the boundary with training of storms possible. For now have 1-2" rains north of I80, which may be conservative. WPC has 2-2.5" rains in the same area, and has highlighted the area in a slight risk for excessive heavy rainfall. Will continue to monitor later model runs for placement of potential heavy rain band. Whatever MCS develops Tuesday evening should continue to push eastward and will clear the area after midnight. Unsure if there will be any additional development along the front as models disagree, but will keep chance pops in just in case. The frontal boundary continues to make slow progress through the area on Wednesday. A secondary upper level impulse may allow additional convection to develop along/south of the front through the day Wednesday that would linger into Wednesday night. SPC has the area along/south of I80 in a marginal risk for severe storms that day. .LONG TERM...(Thursday through Sunday) Issued at 331 AM CDT MON AUG 22 2016 First couple of days of the extended period will be below normal with daytime highs in the mid to upper 70s as we remain on the north side of the cool front. Will maintain a slight chance of thundershowers along the KS/NE border region Thursday into Thursday night. GFS is drying during this time, but the ECMWF is just a little further north with the moisture associated with a southern stream trough. Precip chances do increase Saturday through Sunday as the next upper trough begins to affect the region. && .AVIATION...
-- Changed Discussion --
(18Z TAFS for KOFK...KLNK and KOMA.) Issued at 1221 PM CDT MON AUG 22 2016 VFR conditions are expected through the period. Gusty south winds are expected this afternoon that will diminish and back this evening. Will include some low-level wind shear at KOFK where we expect a stronger low-level jet to develop. Otherwise we will see some increase in mid and high level clouds late tonight and into the day on Tuesday. Gusty winds will again increase on Tuesday morning. Any precipitation is likely to hold off until after 18Z.
-- End Changed Discussion --
&& .OAX Watches/Warnings/Advisories... NE...None. IA...None. && $$ SHORT TERM...DeWald LONG TERM...DeWald AVIATION...Boustead is the U.S. government's official web portal to all federal, state and local government web resources and services.