Severe Storm Outlook Narrative (AC)
Issued by NWS
Issued by NWS
374 ACUS02 KWNS 150450 SWODY2 SPC AC 150448 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1148 PM CDT Sun Jun 14 2026 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE MIDWEST... ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across parts of the Midwest into Lower Michigan. ...Midwest... A midlevel shortwave trough will migrate east across the Midwest and Great Lakes on Tuesday. This will support a band of enhanced midlevel southwesterly flow across portions of WI/IL and into IN/Lower MI/OH during the afternoon and evening. Cooling aloft will result in steep midlevel lapse rates and support MLCAPE up to 1500 J/kg. A weak cold front will move across the region during the afternoon/evening, and a band of convection will develop ahead of this feature. The main limiting factor precluding higher severe probabilities at this time is the expectation for meager boundary layer moisture. Surface dewpoints will generally be in the mid/upper 50s to near 60 F. Forecast soundings indicate sufficient deep layer shear for transient supercells and clusters with a risk for isolated hail and strong wind gusts. ...Northern Oklahoma vicinity... Some forecast guidance suggests storms may develop across parts of northern OK during the late afternoon/early evening as midlevel flow increases within a strengthening warm advection regime. However, given a lack of large-scale ascent or focus for thunderstorm initiation other than strong daytime heating for an increasing moist airmass, confidence in sustained thunderstorm development is low. If storms can develop and be maintained, a risk for strong gusts and isolated hail will be possible. If confidence increases, low unconditional severe probabilities could be needed. ...Eastern Montana/Western North Dakota... Strong storms are expected to develop within strong northwesterly deep layer flow over the Canadian Prairies Tuesday afternoon/evening. This activity will quickly develop southeast into MT/ND by late afternoon/evening. Strong heating amid meager low-level moisture will result in deep boundary layer mixing and weak instability. Locally gusty winds could accompany this activity. ..Leitman.. 06/15/2026 $$