Area Forecast Discussion
Issued by NWS Springfield, MO
Issued by NWS Springfield, MO
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494 FXUS63 KSGF 260534 AFDSGF Area Forecast Discussion National Weather Service Springfield MO 1234 AM CDT Sun May 26 2024 .KEY MESSAGES... - Slight (2 of 5) to Moderate (4 of 5) Risk for severe thunderstorms late tonight into Sunday morning (between 11 pm - 7 am). Damaging winds up to 80 mph and hail up to baseballs are the primary potential severe weather hazards. There is also a conditional risk for a few tornadoes. - Flood Watch in effect tonight for the entire area. Repeating thunderstorms could produce 1-3 inches of rainfall. - Slight (2 of 5) to Enhanced (3 of 5) Risk for severe thunderstorms on Sunday afternoon and evening. Primary hazards are damaging winds up to 70 mph and large hail up to golf balls. && .SHORT TERM /THROUGH MONDAY/... Issued at 255 PM CDT Sat May 25 2024 This Afternoon-Evening: A warm front is lifting north through the area this afternoon ahead of the next approaching shortwave trough. Ahead of this next system late tonight into Sunday, a rather dry and warm afternoon is unfolding. Highs will range from lower to middle 80s across the area, with dewpoints climbing into the middle to upper 60s, near 70 as the front warm front lifts into central Missouri. Expectations are for the area to remain capped through the afternoon and evening. This has been well captured by the guidance. Supercell thunderstorms will develop west of the area across the Southern/Central Plains, with a Moderate Risk (4 of 5) draped across this area. Tonight: By tonight, the atmosphere becomes primed for development of severe thunderstorms. A brief overview of the environment, depicts instability around 2000 to 4000 J/kg in the vicinity of 0-6 km deep layer shear of 35 to 40 knots. Both deep layer and low-level shear will be on the increase into tonight. Additionally, a low-level jet around 45 to 50 knots builds into the area tonight, which will further amplify low- level flow into the region. This will correspond to strong mid- level flow around 500 mb. SPC highlights a Moderate Risk (4 of 5) into southeast Kansas and southwest Missouri. Further east, Enhanced (3 of 5) to Slight (2 of 5) risk exists into Missouri. Ongoing supercell thunderstorms to the west will slowly slide into the area, generally after midnight for portions of far southeast Kansas and along the Missouri/Arkansas border. Supercell coverage may not be widespread, though the activity that is present will likely be intense. Initial thought is that activity will remain semi- discrete in nature for areas along and west of Interstate 49. Hazards in this area include destructive damaging wind gusts up to 80 mph, large hail up baseballs, and a strong tornado or two. The tornado environment is characterized by sufficient 0-1 km shear around 25 to 30 knots and SRH values around 250 to 300 m2/s2. With winds slightly backed out of southeast and low LCLs, mature supercells may be able to tap into a favorable low-level environment. However, a tornado outbreak is not expected at this time as the window for tornadic development in short-lived before the activity grows upscale. Additionally, steep mid-level lapse rates and ample instability through the hail growth zone supports large hail. Large Hail Parameter paints a picture of values greater 20. As thunderstorms push further east towards Highway 65 in the early morning hours, the transition from supercells into line segments is expected. The primary hazard will become damaging wind gusts up to 80 mph, with less focus on large hail. As for tornadoes, 0-3 km shear around 25 knots from the west- southwest, would support a few brief and weaker tornadoes where the segments are able to become balanced along the UDCZ and bowing structures exist. CAMs suggest this line of thunderstorms to persist into central and south central Missouri, towards sunrise Sunday morning. Damaging wind gusts of 60 to 70 mph will be the primary risk with a gradual "weakening" trend east of Highway 65, though some guidance suggests otherwise. This will need to be monitored closely with radar and mesoscale trends. There is an additional concern for localized heavy rainfall and flooding across the area. HREF highlights a few corridors, particularly across west central into central Missouri of 1 to 3 inches or more in short periods of time where thunderstorms train over the same areas. Pinning down these exact locations in subjective in nature, but the general consensus is that the conditions are favorable for heavy rainfall with efficient rainfall rates to produce flash flooding. Additionally, there may be some backbuilding in the vicinity of the warm front and nose of the low-level jet into this area. A Flood Watch has been issued for late tonight (1 AM Sunday) through Sunday evening (7 PM) to account for this increasing potential. Sunday: The overnight MCS complex will be ongoing Sunday morning across portions of central and south central MO. How the overnight MCS evolves through Sunday morning will play a key role in the potential for additional strong to severe thunderstorms Sunday afternoon and evening along the trailing cold front. If thunderstorms are able to redevelop, the atmosphere will be supportive of large hail up to golf balls and damaging wind gusts up to 70 mph. The area of greatest risk extends from central into south central Missouri where an Enhanced (3 of 5) Risk exists. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... Issued at 255 PM CDT Sat May 25 2024 (From Previous AFD) Upper level wave will push through on Sunday night with a drier air mass moving into the area. This should clear the convection to the southeast of the area with temperatures dipping into the upper 50s to low 60s. An upper low in Canada will drop southeast into the Great Lakes region early in the week bringing more of a northwesterly flow aloft to the area. The best moisture axis should remain over the deep south into the southern plains with precipitation chances fairly low for the first half of the work week. An upper level ridge will begin to push into the area on Thursday with moisture beginning to increase over the western CWA by late in the week. Temperatures in the long term period look to remain seasonal for this time of year. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1229 AM CDT Sun May 26 2024 For the 06z TAFS, some isolated/scattered strong to severe convection over northeast OK and southeast KS will push into the area over the next several hours affecting all 3 TAF sites. Additional convection to the northwest in northeast KS will likely form into a squall line and dive southeast into the area, possibly affecting SGF between 11z and 16z this morning. Scattered afternoon convection can`t be ruled out, but most of this activity should stay north and east of the forecast points. The strong and severe convection will have the potential for large hail and severe wind gusts. Things should clear out during the early evening hours. && .SGF WATCHES/WARNINGS/ADVISORIES... KS...Flood Watch through this evening for KSZ073-097-101. MO...Flood Watch through this evening for MOZ055>058-066>071- 077>083-088>098-101>106. && $$ SHORT TERM...Perez LONG TERM...Perez AVIATION...Lindenberg