76°F
Updated:
7/26/2024
9:26:29pm
![](./ajax-images/spacer.gif)
Forecast Discussion
NWS Omaha/Valley, NE
178 FXUS63 KOAX 262322 AFDOAX Area Forecast Discussion National Weather Service Omaha/Valley NE 622 PM CDT Fri Jul 26 2024 .KEY MESSAGES... - There will be a lower chance (25 to 40 percent) of thunderstorms Sunday evening. A few of these storms may be on the stronger side with gusty winds the primary hazard. - Another system will bring chances for storms (20 to 35 percent) Tuesday and Wednesday evenings. - Temperatures are expected to warm into the middle of next week, with Wednesday looking to be the hottest day of the forecast. The highest heat indices are expected across southeast Nebraska. && .DISCUSSION... Issued at 253 PM CDT Fri Jul 26 2024 Today and Tomorrow... A high-amplitude positively tilted ridge continues to persist across much of the western and central CONUS. This will keep skies clear and temperatures warm for the rest of the day. Hazy conditions are expected to persist today into tomorrow as residual smoke from wildfires in the Pacific Northwest and western Canada continues to linger. Tomorrow, a weakening mid-level disturbance will drift northeast into the central Mississippi River Valley. PVA on the north side of this system in combination with CAPE around 1500 J/kg will bring a very low end chance (10 to 20 percent) for a stray shower or thunderstorm south of I-80. Any convection that can initiate tomorrow afternoon will be diurnally driven, and as such will weaken and should dissipate shortly after sundown. Sunday and Monday... There is fairly good consensus amongst short term guidance in a weak low-amplitude disturbance ejecting out into the central and northern Plains Sunday afternoon. At the surface, a low-pressure system will develop in the vicinity of the Black Hills and track east-southeast through the evening hours into southeast South Dakota. South of the pressure center, a dryline will extend south through central Nebraska, with surface dew points in the upper 60s and low 70s to the east of the boundary. By late afternoon, isolated thunderstorms (25 to 40 percent chance of rain) are expected to initiate along the dryline and move to the east. These storms will likely have high LCLs, ranging from 1000 to 2000 feet. Low relative humidities in the boundary layer suggest that strong gusty winds will be the most likely hazard with these storms. The higher end gusts may range from 50 to 60 miles per hour, though any severe wind that does occur should remain very isolated at best. Thunderstorms will weaken as they move west and after sundown, with the strongest storms anticipated west of the Missouri River. Monday morning, a weak cold front will push south across the region. Moisture pooling along the front in conjunction with evapotranspiration will mitigate any cooling effect this will have, with the only noticeable change being a shift of wind direction from south to north. Furthermore, subsidence on the backside of the front may help bring smoke aloft to the surface, slightly reducing visibilities and air quality for a few hours after frontal passage. Winds are expected to become southerly again Monday night as a surface high pressure moves south and east of the area. Tuesday and Wednesday... Medium range guidance suggests that the high-amplitude ridge over the western and central CONUS will breakdown over the Plains, resulting in more zonal flow aloft. Embedded in this broader scale flow, embedded low-amplitude perturbations will traverse the northern CONUS. Though the exact timing and intensity of these disturbances is still uncertain, there is increasing agreement among models in low-end (20 to 30 percent) chances for thunderstorms Tuesday and Wednesday in the afternoon and early overnight hours. Tuesday, the primary mitigating factor to any thunderstorm development will be a strong capping inversion over the region. Wednesday, height falls due to a more robust disturbance will help erode this cap. However, the surface front may push south and east of the area before any convection can develop. As such, will continue to monitor trends the next few days. If thunderstorms are able to develop either of these days in our area, some may be on the stronger side with gusty winds and small hail as the primary hazards. These two days are also projected to be the warmest days of the forecast period as of now. Afternoon highs will range from the mid 90s (north of I-80 and east of US-77) to near 100 degrees (southeast Nebraska and Knox County). As such, heat indices will likely range from 100 to 110 both days later in the afternoon. However, there are several caveats to this. First, new wildfires out west may reintroduce smoke into our area which would keep temperatures a degree or two cooler than what we`re currently forecasting. Because these fires are new, there is some uncertainty in model guidance as to how much smoke will be generated and where this smoke will be transported. Also, if convection either day is able to develop, precip from these storms would locally bring down afternoon highs by several degrees. Thursday and Friday... Ridging will build out west by the end of next week with the return of northwesterly flow aloft over our area. At the surface, a high pressure is expected to move south into the northern Plains and Midwest from Canada. As such, temperatures are expected to cool down somewhat, with afternoon highs ranging from the upper 80s further north to the mid 90s near the Kansas border. && .AVIATION /00Z TAFS THROUGH 00Z SUNDAY/... Issued at 622 PM CDT Fri Jul 26 2024 VFR ceilings through the TAF period. Isolated convection across southeast Nebraska has dissipated, though cannot rule out additional storms while daylight persists. Activity appears to be associated with low level diabatic forcing and H7 frontogenesis. Activity has remained south and east of TAF sites, and don`t plan to include. Otherwise, hazy skies persist early this evening across the forecast area with mainly high level smoke circulating around mid- level ridge axis. Area ASOS depicting visibilities 6 to 9 SM with HZ currently, thus some particulate trapped near ground. Decoupling will allow MVFR-low VFR visibility to persist during the overnight hours. Short- term ensembles gradually dissipate smoke concentration through early afternoon Saturday. As a mid-level disturbance lifts northward from lower Arkansas River Valley into lower Missouri Valley, there are small chances (10-15%) of isolated convection after 20Z Saturday, but will leave out of TAF for now. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...None. IA...None. && $$ DISCUSSION...Darrah AVIATION...Fortin
NWS OAX Office Area Forecast Discussion
Forecast Discussion
NWS Hastings, NE
411 FXUS63 KGID 262313 AFDGID Area Forecast Discussion National Weather Service Hastings NE 613 PM CDT Fri Jul 26 2024 .KEY MESSAGES... - Weakening showers/storms may move across the area Saturday night into Sunday morning. Severe weather is not expected. - Isolated to widely scattered storms are expected to redevelop Sunday afternoon through Sunday night. Most areas will probably remain dry, but some of the storms could be strong to marginally severe. - Dangerous heat returns next week. Tuesday and Wednesday are expected to be the hottest days. && .DISCUSSION... Issued at 352 PM CDT Fri Jul 26 2024 Visible satellite only shows some diurnally-driven cumulus over southeastern portions of the area, with mostly clear skies across the rest of the area. Smoke concentration is also on a decreasing trend, reducing some of the hazy skies that have plagued the area over recent days. Saturday will be similar to today, and is actually expected to be the coolest day until AT LEAST late next week. Regardless, the expected high temperatures in the 90-98 degree range would still be a few degrees above normal. Scattered thunderstorms are expected to develop over western Nebraska in response to a shortwave aloft. The local area will remain dry during the daytime, but many short term models are now showing some of this activity moving through Saturday night into Sunday morning. Storms will be on a weakening trend, and many areas will miss out entirely, but some small PoPs were added to account for this potential. The warming trend begins on Sunday, with portions of Kansas and SW Nebraska reaching 100 degrees. This warmth, combined with increasing wind speeds aloft, will provide an environment favorable for strong to severe storms Sunday afternoon through Sunday night (MUCAPE 1500-3000J/kg and 30-40kt bulk shear). That said, storm coverage is still pretty quite uncertain, with many models keeping most (or all) of the forecast area dry. The broad "Marginal" Risk from SPC seems appropriate at this time, though this could be upgraded if confidence in coverage increases. Heading into the workweek, the main story is the heat. Tuesday and Wednesday are still expected to be the warmest days. On these days, there is a high likelihood of reaching advisory criteria (heat index 105+) for at least parts of the area, and southern zones could even approach Excessive Heat Warning criteria (110+). A shortwave provides some low chances for rain/storms Wednesday into Thursday, along with possibly a minor cooldown. That said, global ensembles still favor slightly above normal temperatures into next weekend and hint at another heatwave for the following week (Aug 4-8). This continued heat, along with a lack of precipitation may lead to rapid onset drought in some areas. Based on the 12Z EPS ensemble, the chance for anything more than 0.50" of rain through the next 10 days is low (10-40%). && .AVIATION /00Z TAFS THROUGH 00Z SATURDAY/... Issued at 609 PM CDT Fri Jul 26 2024 For KGRI/KEAR Airports: VFR conditions are expected the TAF period. Mainly southerly winds will prevail through the period. Wind speeds of 10 to 15 kts are expected this evening and overnight, increasing shortly after sunrise Saturday morning to 15-20 kts sustained with gusts to around 25 kts. Late Saturday morning, winds will increase slightly with gusts of 25 to nearly 30 kts, persisting through the end of the TAF period. Skies will be mostly clear through the TAF period with a few cirrus clouds moving in Saturday afternoon. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ DISCUSSION...Mangels AVIATION...Hickford
Navigation