Area Forecast Discussion
Issued by NWS Hastings, NE
Issued by NWS Hastings, NE
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063 FXUS63 KGID 071130 AFDGID Area Forecast Discussion National Weather Service Hastings NE 630 AM CDT Fri Jun 7 2024 .KEY MESSAGES... - Rain and thunderstorms are expected to move into the area late this afternoon and persist into the overnight hours. Some of these storms may be strong to severe with isolated tornadoes, large hail, and damaging wind gusts all possible. Heavy rainfall is also possible. The entire forecast area is in a Slight Risk (2 out of 5) for severe thunderstorms today per the latest SPC outlook. - Very warm temperatures expected today before cooler weather returns this weekend and early next week. Warmer weather is expected to return again around the middle of next week. - There is at least a slight chance (20%) of showers and thunderstorms much of the forecast period (Saturday through next Thursday). && .DISCUSSION... Issued at 333 AM CDT Fri Jun 7 2024 Today/Tonight... Aloft at 500 hPa, there is a trough over much of the eastern CONUS and a weak ridge over much of the western CONUS north of a broad area of high pressure centered over Texas and the desert southwest this morning. At the surface, high pressure over the MO/AR border will continue southeast and a weak low over srn UT will push east today. There will be a chance of isolated showers/storms this morning, but that will not be the main concern. A pronounced shortwave trough will move across the area this afternoon/evening, and there will be enough instability and shear to support thunderstorms. CAPE values of 2000+ J/kg, 0-6 km shear of 50-60 kts, and strong SRH (particularly 0-3 km values) support strong to severe storms over at least northern and eastern portions of the forecast area. Current expectations is for thunderstorms to initially develop as supercells this afternoon and then evolve into a line or lines of thunderstorms as they move southeast this evening. The greatest large hail threat would be realized with the supercell activity (as would the tornado risk, although that chance is lower), and the greatest damaging wind risk would exist as the storms become more linear. While the majority of the severe activity is expected to be to our north and east, but there is a lot of uncertainty regarding how far southwest into our forecast area this reaches. The most likely timeframe for severe storms will be around 5PM to midnight, but if storms are able to develop further west and earlier, this activity could start as early as 2 or 3 PM. With southerly winds bringing in a significant increase in moisture, some areas may see heavy rain with this system, potentially over an inch, again mainly across northern and eastern portions of the area. Temperatures will be very warm today with highs mainly in the upper 80s to low 90s. Saturday - next Monday: Temperatures will be cooler behind the front, with highs Saturday mainly in the 70s across south central Nebraska and into the low 80s across north central Kansas. Highs Sunday and Monday will be in the 70s. The central Plains will be under WNW flow aloft with embedded shortwaves through the weekend, so there will be at least low chances (~20%) of showers and thunderstorms, mainly Saturday. Sunday night/Monday, there is already a fair amount of model uncertainty regarding the next system. The ECMWF indicates an upper ridge over the area where the GFS and NAM indicate an upper trough but guidance diverges regarding how close the upper low is to the forecast area. Kept PoPs low (~20%) but if models trend toward the solution that brings the upper low into eastern Nebraska/western Iowa (GFS) they would need to be increased. Next Tuesday - next Thursday: Temperatures will begin to increase going into the middle of next week. There is still a decent spread due to the uncertainty of the overall pattern Tuesday, but went with gradually warming temperatures and highs mainly in the 70s. With better model consensus indicating high pressure moving over the area mid- week, there is more confidence regarding a return to warmer temperatures next Wednesday and Thursday, with highs mainly in the 80s Wednesday and into the 90s in many areas Thursday. The area should be mostly dry, but a few thunderstorms may be possible each evening. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 617 AM CDT Fri Jun 7 2024 VFR conditions are expected through the day Friday, with a low chance (20%) for MVFR CIGS across the TAF sites early Saturday morning. Showers and thunderstorms will move through the area Friday evening into early Saturday morning. Winds will be southerly and light through the majority of Friday morning. Wind speeds will increase to around 15 kts sustained with gusts to around 25 kts Friday afternoon and early evening. Winds will be southeasterly at around 10 kts Friday evening, but may become gusty and erratic near any thunderstorms (more likely at KGRI than at KEAR). Winds will become easterly late this evening, then northerly toward the end of the TAF period. Regarding showers and thunderstorms Friday evening...strong to severe storms are possible, but the majority of the thunderstorm activity is expected to remain north and east of the TAF sites. There is a little more model consensus, so introduced -TSRA this evening for KGRI and VCTS for KEAR. There is a 20% chance of CIGS dropping to MVFR near the end of the TAF period, but confidence is too low to include in the TAFs. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ DISCUSSION... AVIATION...Hickford