The Storm Prediction Center convective weather outlook is part of the National Weather Service (NWS) and the National Center for Environmental Prediction (NCEP). Their mission is to provide accurate forecasts and monitor the timing of thunderstorms and severe storms in the United States. The SPC provides convective outlooks on Day 1, Day 2, and Day 3 that reflect the overall level of severe weather hazard outlooks through a list of forecast statistics. This data identifies areas at risk of mild thunderstorms and severe thunderstorms. For more information on how to read this map, please see the bottom of this page.
Convective Outlook Day 1
SPC Day 1 Outlook Discussion
ACUS01 KWNS 041200 SWODY1 SPC AC 041158 Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0658 AM CDT Thu Jun 04 2026 Valid 041300Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING OVER PORTIONS OF THE NORTHERN PLAINS.... ...SUMMARY... Severe thunderstorms capable of large to very large hail and damaging winds are possible today from parts of the northern High Plains across northern Nebraska and much of South Dakota. More isolated occurrences of large hail and damaging winds appear possible farther south across portions of the central Plains. ...MT/Dakotas/MN... Fast zonal flow is present today over the northern U.S, with a shortwave trough now over western MT approaching the northern High Plains. Easterly low-level winds have transported 50s dewpoints westward into southeast MT/northeast WY, where daytime heating and increasing large-scale ascent will lead to scattered afternoon thunderstorms. Coverage of storms is not expected to be very high, but those cells that can develop will likely be supercells capable of large hail and damaging wind gusts. Storms will spread into the central Dakotas through the evening with a continued severe threat. Farther east, a surface boundary is forecast to extend from south-central SD into central MN. Strong heating in this corridor will promote scattered thunderstorms after 20z. Forecast soundings suggest an environment favorable for hail and damaging winds in the strongest cells. ...KS/NE/IA... A weak upper trough has emerged from the central/southern High Plains overnight and is now moving across western KS. Radar loops show an MCV near Hays KS that will track into southeast NE and western IA later today. A combination of low-level convergence, daytime heating, and the affects of the MCV will lead to scattered afternoon thunderstorms from northeast KS into IA. CAPE values of 2000-3000 J/kg are expected, along with sufficient deep-layer shear for multicell or perhaps supercell storm structures. The potential exists for hail and damaging wind gusts in the stronger cells this evening. An upgrade to SLGT was considered, but the shield of clouds/precip in vicinity of the MCV limits confidence in heating and the area of greatest concern at this time. ..Hart/Kerr.. 06/04/2026 $$ |
Convective Outlook Day 2
SPC Day 2 Outlook Discussion
ACUS02 KWNS 040523 SWODY2 SPC AC 040521 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1221 AM CDT Thu Jun 04 2026 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS CENTRAL AND EASTERN NEBRASKA...NORTHERN KANSAS... MUCH OF IA...INTO SOUTHERN MINNESOTA AND SOUTHWEST WISCONSIN... ...SUMMARY... Scattered severe storms capable of large to very large hail, damaging winds with potentially significant gusts, and perhaps a couple of tornadoes are expected Friday afternoon into night across portions of the central Plains into upper Great Lakes. ...Synopsis... A series of weak, mid-level disturbances will translate from the northern Plains into the upper Great Lakes, ahead of a building ridge from central Canada into the northern Plains. At the surface, the primary focus for strong to severe thunderstorm development is a front, which is expected to stretch from the western UP of MI southwest through the mid MO Valley into the central High Plains by mid-afternoon Friday. A surface low is forecast to develop along the front over south-central NE or north-central KS, with a dryline extending south-southwest from that feature into northwest OK. ...Central Plains into the Upper Great Lakes... Latest guidance is suggestive that the combination of steep mid-level lapse rates and boundary-layer dewpoints in the upper 60s to low 70s will support strong instability along and south of the NE/IA segment of the front with HREF mean SBCAPE as high as 3000-4000+ J/kg. Forecast instability decreases with northeastward extent into the upper Midwest, due in part to the potential for early-day storms and lingering cloud cover. While mid-level heights are forecast to rise through the day across the central Plains, strong heating west of the dryline and south of the surface front should sufficiently erode the cap for isolated to widely scattered thunderstorm development by late afternoon into early evening in the vicinity of the triple point over south-central NE. Locally backed near-surface winds in that area will offset somewhat marginal mid-level flow to yield 30-35 kt of deep-layer shear, which will support supercell storm modes, given the degree of instability. Large to very large hail and perhaps a couple tornadoes will be possible in the early life cycle of the storms, with a subsequent transition to more of a damaging wind threat (with significant gusts possible) by mid/late evening. Additional severe storms are expected farther east along the front into IA during the afternoon and evening hours with strong instability and modest vertical shear supporting a threat for large to very large hail and severe wind gusts. Should subsequent model guidance show higher confidence in more concentrated storm development along the NE/IA segment of the front, an upgrade to a level 3/Enhanced Risk may be considered. Farther northeast along the front across the upper Midwest, the diffuse nature of the boundary casts some uncertainty on exactly where the favored area for diurnally enhanced storm development will be. Nonetheless, the presence of a moderately unstable air mass and modest deep-layer shear will be supportive of a few severe storms capable of large hail and damaging wind gusts. An isolated severe-weather threat may continue to spread east into the upper Great Lakes Friday evening into night, driven largely by warm advection along a westerly low-level jet. ..Mead.. 06/04/2026 $$ |
Convective Outlook Day 3
SPC Day 3 Outlook Discussion
ACUS03 KWNS 040728 SWODY3 SPC AC 040727 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CDT Thu Jun 04 2026 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST LOWER MICHIGAN...NORTHERN AND CENTRAL OHIO...WESTERN PENNSYLVANIA...FAR WESTERN NEW YORK...NORTHEAST MONTANA...AND WESTERN NORTH DAKOTA... ...SUMMARY... Scattered severe storms capable of large hail and damaging winds are possible from portions of the Great Lakes and Ohio Valley into the Northeast, and over the northern High Plains. ...Synopsis... A short-wave trough and attending belt of 40-50 kt mid-level winds initially over the Great Lakes will overspread the Northeast and Mid-Atlantic Saturday into Saturday night. Meanwhile, an intense upstream trough is forecast to move through the Canadian Rockies and Pacific Northwest into the northern Rockies, with downstream height falls and strengthening mid/upper-level winds advancing into the northern High Plains. Elsewhere, a mid-level low initially centered along the NM-TX state line is expected to evolve into an open wave while lifting northeast across the central and southern Plains. At the surface, a cold front will push through the Great Lakes, New England, and OH Valley during the forecast period, while a lee cyclone deepens along a cold front moving through the northern High Plains. ...Great Lakes and OH Valley into the Northeast... A westerly low-level jet will advect an increasingly moist air mass through the Great Lakes and OH Valley into the Northeast ahead of the cold front on Saturday. The moisture increase will combine with daytime heating to support a moderately unstable environment across the OH Valley, with instability diminishing with northeastward extent into New England. Thunderstorms are expected to increase in coverage and intensity through the afternoon ahead of the short-wave trough, and amidst a kinematic environment featuring 30-40 kt of deep-layer shear. The most favorable overlap of stronger instability, vertical shear, and forcing for ascent is expected to materialize across the upper OH Valley Saturday afternoon, where supercells will be possible with a higher-probability risk for large hail and damaging winds. Elsewhere, isolated occurrences of large hail and/or damaging wind will be possible during the afternoon and evening hours. ...Northern High Plains... The presence of steep lapse rates and increasing boundary-layer moisture content are expected to contribute to a moderate to strongly unstable air mass by afternoon ahead of the surface low and cold front over eastern MT and western ND. Moisture wrapping around the surface low is expected to reach into the high terrain of central MT, supporting at least modest destabilization there. Initial, isolated storms are expected in the post-frontal, upslope environment in central MT Saturday afternoon, with storms potentially not developing until Saturday evening in the vicinity of the front in eastern MT and western ND, due to late-arriving forcing for ascent. Vertical shear will strengthen through the day with the kinematic environment favoring supercell storm modes with the primary hazard being large hail. ...Southern Plains.... The models indicate a band of 30-35 kt mid-level winds developing within the southeast quadrant of the upper low from southwest TX into the Red River Valley Saturday afternoon. As a result, vertical shear will be enhanced in those areas; however, the primary uncertainty regarding some severe-storm threat is the effect of early-day storms on afternoon air mass destabilization. ..Mead.. 06/04/2026 $$ |
Convective Outlook Day 4-8
SPC Day 4-8 Outlook Discussion
ACUS48 KWNS 040854 SWOD48 SPC AC 040852 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0352 AM CDT Thu Jun 04 2026 Valid 071200Z - 121200Z ...DISCUSSION... ...Day4/Sunday... A short-wave trough initially from the lee of the Canadian Rockies into the northern Rockies is forecast to lift northeast into central Canada, while a lower-latitude wave moves through the central and southern Plains toward the MS Valley. Elsewhere, a short-wave trough will traverse the Northeast and Mid-Atlantic. At the surface, a cold front will slowly advance across the northern Plains, while a separate cold front moves south through the Mid-Atlantic. The strongest mid/upper-level winds and associated vertical shear will lag the northern Plains cold front to the west; however, the presence of moderate to strong instability within the warm sector may compensate, yielding the potential for an organized severe-weather event Sunday afternoon and evening. Elsewhere, isolated to widely scattered severe storms appear possible along the Mid-Atlantic cold front, as well as across lower elevations of central and southern Plains into Ozark Plateau, in association with the mid-level trough. ...Day5/Monday... Ensemble mean and deterministic model solutions are in good agreement in suggesting that a mid-level trough will move onto the West Coast, with a downstream belt of stronger winds remaining confined to the Interior West. At the surface, a cold front initially from the ND-MN Red River Valley into central High Plains will weaken through the day in response to falling pressures over the Rockies. Isolated severe storms appear possible along the segment of the front immediately east of a surface low over western KS where strong instability is forecast. However, generally weak forcing for ascent and marginal vertical shear may limit the potential for an organized severe-weather episode. ...Day6/Tuesday... The ensemble mean and deterministic model solutions remain in relatively good agreement in depicting the continued amplification of the mid-level trough over the western U.S., with a belt of stronger winds aloft overspreading the northern Plains. At the surface, there is reasonably good ensemble clustering in the location of a deepening lee cyclone over the northern High Plains, with a lee trough extending through the central into southern High Plains. While large-scale forcing for ascent remains somewhat nebulous, low-level convergence in the vicinity of the surface low and lee trough should be sufficient to initiate afternoon/evening thunderstorms within an environment favoring the potential for a concentrated area of severe weather. ...Day7-8/Wednesday and Thursday... The ensemble mean solutions suggest the main trough becoming quasi-stationary over the Interior West. There is considerably more spread in the deterministic models, especially by Thursday, in the location and geometry of the mid-level trough, as well as any smaller-scale disturbances embedded within it. At the surface, there is fairly large spread in ensemble member low pressure positions, and the location of any associated boundaries. In general, it appears that some severe-weather threat will continue across the northern Plains; however, confidence in a more specific details is currently too low to delineate an area. ..Mead.. 06/04/2026
Convective Weather Outlook Legend Data
- TSTMÂ (light green) – General or non-severe thunderstorms – Delineates, to the right of a line, where a 10% or greater probability of thunderstorms is forecast during the valid period.
- 1-MRGL (dark green) – Marginal risk – An area of severe storms of either limited organization and longevity, or very low coverage and marginal intensity.
- 2-SLGT (yellow) – Slight risk – An area of organized severe storms, which is not widespread in coverage with varying levels of intensity.
- 3-ENHÂ (orange) – Enhanced risk – An area of greater (relative to Slight risk) severe storm coverage with varying levels of intensity.
- 4-MDT (red) – Moderate risk – An area where widespread severe weather with several tornadoes and/or numerous severe thunderstorms is likely, some of which should be intense. This risk is usually reserved for days with several supercells producing intense tornadoes and/or very large hail. Or an intense squall line with widespread damaging winds.
- 5-HIGH (magenta) – High risk – An area where a severe weather outbreak is expected from either numerous intense and long-tracked tornadoes. Also, a long-lived derecho-producing thunderstorm complex that produces hurricane-force wind gusts and widespread damage. This risk is reserved for when high confidence exists in widespread coverage of severe weather with embedded instances of extreme severe. (i.e., violent tornadoes or very damaging convective wind events).
This data is courtesy from the Storm Prediction Center