Area Forecast Discussion
Issued by NWS Springfield, MO
Issued by NWS Springfield, MO
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562 FXUS63 KSGF 060854 AFDSGF Area Forecast Discussion National Weather Service Springfield MO 354 AM CDT Mon May 6 2024 .KEY MESSAGES... - Strong to severe thunderstorms late this evening into Tuesday morning, with the greatest risk west of Highway 65. SPC highlights an Enhanced Risk (3/5) for this area. Primary hazard is damaging wind gusts of 70 to 80 mph. Additional hazards include a few short-lived tornadoes and half dollar sized hail. - Additional strong to severe thunderstorms on Wednesday. Exact hazards remains in question, but very large hail, damaging, and a conditional tornado threat are all in play. SPC has a hatched Enhanced Risk (3/5) for most of the area. && .SHORT TERM /THROUGH TUESDAY/... Issued at 345 AM CDT Mon May 6 2024 Main attention is on severe potential late this evening into tonight, but we do have some ongoing dense fog over western and southern portions of the area. The fog will dissipate this morning. For the rest of today, weather looks quiet until late today. Widespread severe convection is expected west of the CWA during the afternoon, which spread east into the CWA late this evening (most likely after 9pm) into early Tuesday morning as a shortwave and cold front move through. Most likely scenario: Expectation is for storms west of our area to develop strong cold pools with upscale growth to linear storm mode by time storms get into our area. Depending on upstream evolution, more than one line of storms is possible. Forcing from a 110-120kt upper jet streak nosing into the area, a developing 40-50kt LLJ, and the shortwave itself will be supportive of maintaining convection all the way through the eastern CWA by early Tuesday morning. As far as mesoscale analysis, the environment over the western CWA will see the greatest instability with MLCAPE of 1,500-2,500 J/kg, weakening to a still respectable 1,000-1,500 J/kg by time storms reach the eastern CWA. The entire area will see 0-6km shear of 50-60kts and 0-3km shear of 35-40kts. With storm mode expected to be primarily linear with ample shear and strong cold pools, damaging winds up to 70-80 mph will be the primary threat, along with a threat for short lived QLCS tornados in segments bowing to the northeast. Hail up the size of half dollars is also possible, primarily over the western CWA where any storms can develop ahead of the line (or lines). Overall expect a gradually diminishing trend in severe threat as storms move east through the CWA. Alternate scenario over the western CWA: Some guidance is showing discrete convection going up over the western CWA this evening. If that does occur, a narrow corridor mainly along and west of I-49 could see a threat for even larger hail (up to golf ball size), damaging winds, and perhaps tornadoes. This potential will have to be monitored through the day. Storms will exit the area Tuesday morning with clearing skies through the day. Look for highs in the mid 70s to low 80s. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... Issued at 345 AM CDT Mon May 6 2024 For Wednesday: SPC has introduced a hatched Enhanced Risk for most of the area with the greatest concern at this time being potential for very large hail. All modes of severe weather are on the table though. The setup will come from a strong shortwave moving well NW of the area Tuesday night into Wednesday. As it does so, surface low pressure will develop and move from SW KS to northern MO Tuesday night into Wednesday morning. This will pull the cold front that passes through tonight into Tuesday back north as a warm front Wednesday morning, then back to the southeast as a cold front through the rest of the day Wednesday. Threats are tricky at this point given uncertainty in initiation time and storm mode. Could see a variety of storm modes, including supercells, splitting supercells, and multicell clusters. The cold front will move slowly SE through the day, with severe potential along and ahead of the front. Early to mid morning Wednesday: Unsure how much convection will fire during this time, but there is concern that storms will develop along the warm front as it lifts through the CWA, especially the western CWA where a 40-60kt LLJ will be shifting east into the area during the morning. Since the surface low will be to the west or northwest at this point in the day, wind profiles will be supportive of all modes of severe weather, including tornadoes. This is a more conditional threat that will have to be monitored as the event gets closer. Late morning through the evening: The most obvious concern is for large hail from late morning through the evening given good overall agreement in MLCAPE values of 2,000-3,500 J/kg, mid- level lapse rates of 7-8 C/km, and 0-6km shear values of 50-60kts. By time late morning comes around, the low will be over northern MO and shear profiles will be nearly unidirectional, favoring splitting cells. Areas roughly along and south of I-44 are shown by models as having Large Hail Parameter values of 15-25, which is impressive. If ideal storm modes result, the largest hail stones around baseball size are possible if the forecast remains on track. Damaging winds would also be a concern. Little to no tornado threat is expected by this time of day given wind fields becoming unidirectional. For Thursday through Sunday, little to no precip is in the forecast and temperatures should be near normal. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1256 AM CDT Mon May 6 2024 Drizzle and fog are expected early this morning. Will have to watch observations to see how dense fog will become. VFR conditions are then expected today until thunderstorms (some severe) move in from the west late Monday into Monday night. && .SGF WATCHES/WARNINGS/ADVISORIES... KS...Dense Fog Advisory until 9 AM CDT this morning for KSZ073-097- 101. MO...Dense Fog Advisory until 9 AM CDT this morning for MOZ066-077- 082-088-091>097-101>105. && $$ SHORT TERM...Titus LONG TERM...Titus AVIATION...Titus