Area Forecast Discussion
Issued by NWS Omaha/Valley, NE
Issued by NWS Omaha/Valley, NE
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194 FXUS63 KOAX 092315 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 615 PM CDT Thu May 9 2024 .KEY MESSAGES... - Several rounds of showers and thunderstorms are forecast Sunday through Wednesday. Current indications for the greatest precipitation chances of 40-60%, are expected Sunday into Monday. A strong storm or two is possible Sunday afternoon and again on Wednesday afternoon. - Daytime temperatures will be near to slightly above normal for this time of year. && .DISCUSSION... Issued at 347 PM CDT Thu May 9 2024 .Remainder of this afternoon and tonight: Forcing for ascent and resultant cooling aloft/steepening lapse rates associated with a minor vorticity lobe pivoting south through the area have contributed to a weakly unstable environment this afternoon. And, latest CAM data suggest the potential for isolated showers and perhaps a thunderstorm or two this late afternoon into early evening. Both clouds and gusty northwest winds will diminish this evening with lows in the low to mid 40s. Friday and Saturday: Generally quiet weather is anticipated the next couple of days as the region will reside between a shortwave trough diving southeast through the Great Lakes and a lower-latitude trough advancing through the Great Basin and Desert Southwest. It will be breezy Friday with northwest wind gusts of 20 to 25 mph. Furthermore, a few models suggest the potential for isolated showers Friday afternoon in conjunction with the above- mentioned shortwave trough passing to our east. However, confidence in that precipitation potential is currently too low to include in the forecast. In regard to temperatures, highs are expected to be in the 70s both days. .Sunday into Monday night: The 12z global models are in generally good agreement in suggesting that the Great Basin/Desert Southwest trough mentioned above will slowly track across the central and southern Plains during this time period. At the same time, there is some signal that a polar-branch trough could temporarily phase with the primary midlevel system and combine with a surface front moving into the mid MO Valley to yield a good chance (i.e., 40-60% PoPs) of showers and thunderstorms, especially along and south of I-80. The models suggest the potential for modest instability to develop Sunday afternoon amidst a weakly sheared kinematic environment. So while organized severe weather isn`t anticipated, a strong storm or two is possible. The forecast will call for high temperatures in the 70s with overnight lows in the 50s. .Tuesday and Wednesday: A shortwave trough is forecast to advance from the northern Rockies into the northern and central Plains with an associated surface cold front moving through the region Wednesday into Wednesday night. Both the EPS and GEFS indicate the best instability developing across southeast NE and southwest IA Wednesday afternoon, and a few strong storms appear possible. Otherwise, the forecast will indicate increasing shower and thunderstorm chances beginning Tuesday afternoon and continuing into Wednesday night. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 613 PM CDT Thu May 9 2024 VFR conditions expected to persist through the next 24 hours. Winds expected to relax this evening with clouds becoming thinner or clearing out completely. Mid-to-high-level clouds will redevelop by Friday afternoon with winds increasing again out of the northwest gusting to around 20kt. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...Mead AVIATION...McCoy