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MNstorms

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  1. There hasn't been much severe weather to follow as of late. Maybe this weekend will be active. Classic bowling ball on Sunday.
  2. A couple of funnels reported. Nothing on the ground.
  3. Nebraska and Colorado have had tornadoes today with a 0% risk posted. Minnesota to do the same?
  4. Already a day3 enhanced highlighted. Models hint this could be high end event. ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER MIDWEST... ...SUMMARY... Scattered severe thunderstorms should occur Saturday across parts of the Upper Midwest. A few tornadoes, large to very large hail, and significant damaging winds all appear possible. ...Upper Midwest into the Great Lakes... A notable shortwave trough is forecast to progress from the northern Plains east-southeastward across the Upper Midwest and Great Lakes on Saturday. A belt of enhanced mid/upper-level flow will likely accompany this shortwave trough and act to organize thunderstorms that develop ahead of it through the day. There is reasonably good agreement in model guidance that a very moist low-level airmass will be in place ahead of a front across the Upper Midwest Saturday morning. Steepening mid-level lapse rates and robust heating of this airmass through the early afternoon should foster moderate to strong instability. Deep-layer shear will be more than sufficient for organized updrafts, and supercells with a threat for very large hail appear possible with initial convective development across MN. Most guidance also suggests that quick upscale growth into a MCS will occur Saturday afternoon/evening with eastward extent into western/central WI and northeastern IA. Given the degree of buoyancy available, at least scattered damaging/severe winds appear probable as this mode transition occurs. Some of these winds may be significant. Have included an Enhanced Risk where MCS development and propagation appear most likely. Enough low-level shear associated with a southwesterly low-level jet is also forecast to support a threat for a few tornadoes. This severe threat should continue into the Great Lakes region Saturday night, but lesser instability forecast with eastward extent should keep the overall severe threat fairly isolated.
  5. Day 3 enhanced. One of the most extreme forecast soundings I've seen
  6. Both storms have had CC drop but NWS hasn't called them radar confirmed.
  7. Up to 6 total warnings, 4 different rotations. Maybe a quick spin up.
  8. Several QLCS rotations and 70 mph winds possible.
  9. I'm surprised they didn't upgrade to moderate risk for Monday. They do mention there are a couple of concerns. MPX AFD even mentions moderate possible for today. Scattered severe thunderstorms are forecast from parts of the Upper Midwest southward into the central Great Plains on Monday and Monday night. Large to giant hail, 60-80 mph gusts, and several tornadoes are probable, including the possibility for a couple of intense long-track tornadoes over parts of the Upper Midwest. A dynamic late-spring pattern is forecast on Monday into Monday night with the possibility of a severe-weather outbreak over parts of the Upper Midwest. ...Upper Midwest into the central Great Plains... A potent mid-level shortwave trough will eject northeastward from southeast CO northeastward to northern MN while evolving into a mid-level low. An associated 500 mb speed max will intensify during the day with 100 kt southwesterly flow moving from eastern NE into southern MN during the afternoon into the early evening. A cyclone will deepen as it moves from northern KS north-northeastward into eastern SD by mid evening before occluding. A dryline will extend south-southwestward from the lower to mid MO Valley into central KS and near the TX Panhandle/OK border. Isolated elevated thunderstorms are possible early Monday morning on the nose of a strong LLJ in the SD/NE/IA/MN region. This activity will likely dissipate during the morning as a warm front advances northward. Strong southerly flow will advect richer low-level moisture northward into the eastern Dakotas and western MN by midday. Some model guidance indicates storms may develop during the morning over parts of central NE as upward vertical motion increases with the approaching disturbance. Have trended westward with severe-weather probabilities as a result. Forecast soundings become uncapped by midday into the early afternoon over southeast SD with large CAPE (2500 J/kg MLCAPE) and a wind profile strongly supporting supercells. Lowest 100 mb mean mixing ratios 13-14 g/kg in a zone where surface pressure falls will maximize northeast of the surface low, will combine with enlarging hodographs to favor strong supercells. Large to very large hail is probable along with several tornadoes during the afternoon into the early evening. A couple of intense long-track tornadoes are possible if 1) favorable storm mode develops and 2) a notable absence of other convection and destructive storm-to-storm interactions is limited. Additional storms are likely to develop in an arc from southern MN into IA and possibly eastern NE during the late afternoon to early evening. An eventual consolidation of storms and outflow will probably lead to the risk for severe gusts to increase during the evening across MN as the activity quickly moves north-northeastward.
  10. As someone from Minnesota I don't think I've seen this strong of wording here before and it's Day 3. Even June 17, 2010 Day 1 wording looks lighter. At least a moderate risk for Day 2? Also what is the difference between large and giant hail? ...SUMMARY... Scattered severe thunderstorms are forecast from parts of the Upper Midwest southward into the central Great Plains on Monday and Monday night. Tornadoes, perhaps a few strong tornadoes, large to giant hail, and severe gusts are possible. ...Upper Midwest into the central Great Plains... A potent mid-level shortwave trough will move through the base of a larger-scale trough --centered over the Great Basin-- from southeast CO northeastward to northern MN while evolving into a mid-level low by daybreak Tuesday. An associated 500 mb speed max will intensify during the day with 100 kt southwesterly flow progged over eastern Nebraska by the late afternoon. A cyclone will deepen as it moves from northern KS north-northeastward into eastern SD by mid evening before occluding. A dryline will extend south-southwestward from the lower to mid MO Valley into central KS and near the TX Panhandle/OK border. Isolated elevated thunderstorms are possible early Monday morning from remnant storms on the nose of a strong LLJ in the SD/NE/IA/MN region. This activity will likely dissipate during the morning as strong southerly flow advects richer low-level moisture northward into the Upper Midwest by midday. Model guidance indicates mid to upper 60s dewpoints from the Upper Midwest southward into IA. Large-scale ascent associated with the approaching disturbance will likely lead to scattered storms initiating by the early to mid afternoon northeast of the northeastward-developing cyclone. Enlarged hodographs and strong shear through a deep layer will favor supercells, especially in the eastern Dakotas/western MN area during the afternoon. Tornadoes and large hail are possible with the more intense supercells. A few of the tornadoes may be strong given 300+ m2/s2 0-1 km SRH. Additional storms are forecast to develop by the early evening across southern MN into IA with severe gusts becoming increasingly probable, in additional to a lingering hail and perhaps tornado risk. Farther south along the dryline, a capping inversion will weaken by the mid-late afternoon amidst a very unstable airmass (3000-4000 J/kg MLCAPE). Once the cap is breached, rapid supercell development is expected on the southern flank of a cluster of storms from southeastern NE into central KS. Large to giant hail is possible initially, and as the low-level flow increases during the 23-01z period, the risk for a tornado will correspondingly increase along with the risk for a strong tornado. Storms will probably consolidate during the evening as 850 mb flow increases and the risk for a tornado will gradually lessen by mid-late evening as the main threats transition to primarily a wind/hail threat into the overnight.
  11. NAM likes Monday a lot more than Sunday. No cap on Monday.
  12. Sunday Scattered severe thunderstorms are likely over Nebraska northeastward into Minnesota on Sunday and Sunday night. Significant severe weather including very large hail and hurricane-force gusts are possible with the strongest storms. Several tornadoes are also possible. ...Synopsis... The exit region of a powerful, cyclonically curved upper jet is forecast to overspread the central High Plains into the mid MO Valley during the period as a large-scale mid-level trough encompasses the West. A mid-level anticyclone will reside over the Carolinas. In the low levels, a surface front perhaps augmented by convection is forecast to extend from the Upper Midwest southwestward to a triple point near the northwest KS/NE border. A dryline will extend southward into the southern Great Plains. ...Central Great Plains into the Upper Midwest... A strong to severe thunderstorm cluster may be ongoing early Sunday morning over parts of the eastern Dakotas where strong 850 mb theta-e advection is forecast. Isolated hail/wind would be the primary threats with this elevated activity. Farther south, strong southerly flow will aid in moisture transport northward into the mid MO Valley and Upper Midwest. Strong heating, contributing to evapotranspiration beneath a stout capping inversion associated with an elevated mixed layer, will yield a very unstable airmass (3000-4500 J/kg MLCAPE) over parts of NE northeastward into adjacent SD/IA/MN. Forecast soundings show some low-level veering and strengthening of winds with height, strongly supporting supercells with initial storm development during the late afternoon/early evening. Large to very large hail is likely with the more intense supercells. Tornadoes are also possible, especially in warm-sector areas early on where temperature-dewpoint depressions are not too large (less than 20 deg F). An evolution towards clusters is expected during the evening as a central Great Plains LLJ intensifies. A lingering threat for hail/wind will probably continue through the evening into the overnight.
  13. I guess this season is going to be the one that keeps on giving in the Dakotas and Minnesota.
  14. And there it is. 4th tornado watch is the 2nd most since at least 2006 for me and it's only May.
  15. I would think the watch would come any minute now with cells popping and cumulus clouds for awhile now.
  16. Probability of Watch Issuance...95 percent SUMMARY...Supercells are expected to develop this afternoon along a warm front near the Iowa/Minnesota border. These storms would be capable of all severe hazards, including tornadoes and very large hail. A tornado watch is likely within the next 2 hours. DISCUSSION...A warm front continues to lift northward near the Iowa/Minnesota border. Dewpoints near the boundary are generally in the low 60s F. A narrow corridor of low/mid 60s F dewpoints exists in southwestern Iowa with dewpoints in parts of central/eastern Iowa mixing out into the upper 50s F. With an MCV currently in southern/central Missouri, the degree and quality of moisture return is uncertain with eastward extent. The KOAX/KFSD VWP have sampled the 35-40 kts 850 mb winds that are helping to increase low-level shear in the vicinity of the warm front. Objective mesoanalysis is showing near 400 m2/s2 effective SRH right along the boundary in northwest Iowa. Storms that form along and interact favorably with the boundary will be capable of all severe hazards, including tornadoes and very large hail. Should any storms move north of the boundary, the tornado threat would be less, but large/very-large hail would remain possible. Though low-level shear/SRH would suggest the potential for a strong tornado, the continued decrease in dewpoints within western/central Iowa makes this a low-probability scenario. A tornado watch is likely within the next 2 hours.
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