158
ACUS01 KWNS 261235
SWODY1
SPC AC 261233
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0733 AM CDT THU JUN 26 2025
VALID 261300Z - 271200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
ACROSS FAR SOUTHEAST MN...NORTHERN IA AND SOUTHERN WI...
..SUMMARY
A FEW TORNADOES AND ISOLATED WIND DAMAGE WILL BE POSSIBLE THIS
AFTERNOON FROM NORTHERN IOWA AND SOUTHWEST MINNESOTA INTO SOUTHWEST
WISCONSIN. ISOLATED WIND DAMAGE WILL BE POSSIBLE ACROSS A BROAD AREA
OF THE EASTERN PLAINS, OHIO VALLEY, MID-ATLANTIC, THE SOUTHEAST AND
MONTANA.
..SOUTHERN MN/IA/SOUTHERN WI
EARLY MORNING RADAR AND SATELLITE IMAGERY SHOW A WELL-DEFINED MCV
MOVING NORTHEASTWARD INTO EASTERN NE. SURFACE ANALYSIS REVEALS A LOW
OVER EASTERN NE, WHICH IS ASSOCIATED WITH THIS VORTICITY MAXIMUM AS
WELL. A STATIONARY BOUNDARY EXTENDS NORTHEASTWARD FROM THIS LOW
THROUGH NORTHWESTERN IA TO ANOTHER LOW IN THE MN/IA/WI BORDER
INTERSECTION VICINITY. THIS BOUNDARY, WHICH SEPARATES A MOIST
AIRMASS CHARACTERIZED BY 70S DEWPOINTS FROM A MORE CONTINENTAL
AIRMASS WITH LOW 60S DEWPOINTS, COULD ACT AS A FAVORED CORRIDOR FOR
NORTHEASTWARD PROGRESS OF THE SURFACE LOW THROUGHOUT THE DAY. AT THE
SAME TIME, STRENGTHENING SOUTHERLY LOW-LEVEL FLOW WILL INCREASE THE
LOW-LEVEL MOISTURE ADVECTION SOUTH OF THIS BOUNDARY, RESULTING IN
SOME TIGHTENING OF THIS BOUNDARY THROUGHOUT THE DAY. SOME GUIDANCE
SUGGESTS THIS BOUNDARY COULD MOVE SLIGHTLY NORTHWARD AS A WARM FRONT
AS WELL. THIS LOW-LEVEL MOISTURE ADVECTION WILL ALSO HELP OFFSET
SURFACE DEWPOINT REDUCTIONS DUE TO MIXING, WITH DEWPOINTS LIKELY
REMAINING IN THE 70S ALONG AND SOUTH OF THE BOUNDARY. STRONG HEATING
OF THIS MOIST AIRMASS WILL BRING TEMPERATURES IN THE UPPER 70S/LOW
80S, FOSTERING AIRMASS DESTABILIZATION AND STRONG BUOYANCY BY THE
EARLY AFTERNOON.
THUNDERSTORM DEVELOPMENT IS EXPECTED AS THE APPROACHING VORTICITY
MAXIMUM AND ASSOCIATED SURFACE LOW INTERACT WITH THIS UNSTABLE
AIRMASS, WITH INITIATION OCCURRING BOTH NEAR THE SURFACE LOW AS WELL
AS FARTHER EAST AMID THE CONVERGENCE ALONG THE WARM FRONT. THE
DEVELOPMENT NEAR THE LOW SHOULD BECOMING LINEAR QUICKLY WHILE THE
ACTIVITY ALONG THE FRONT SHOULD REMAIN MORE CELLULAR LONGER. THE
INITIAL/MORE DISCRETE STORMS COULD BE SUPERCELLS WITH THE POTENTIAL
TO PRODUCE A FEW TORNADOES WITHIN THE MODERATELY SHEARED AND
VORTICITY RICH ENVIRONMENT ALONG THE FRONT. DAMAGING GUSTS WILL BE
POSSIBLE WITH THE LINEAR SEGMENTS AS WELL, PARTICULARLY IN CLOSE
VICINITY TO THE SURFACE LOW WHERE MESOSCALE CIRCULATIONS COULD
AUGMENT UPDRAFTS AND DOWNDRAFTS.
..CENTRAL/EASTERN KS INTO WESTERN/CENTRAL OK
RECENT SURFACE ANALYSIS REVEALS WEAK SURFACE TROUGHING TO THE SOUTH
OF A LOW OVER EASTERN NE. THIS TROUGHING WILL LIKELY SHIFT EASTWARD
AS ITS PARENT LOW PROGRESSES NORTHEASTWARD, WITH CONVERGENCE ALONG
THIS BOUNDARY CONTRIBUTING TO THUNDERSTORMS ACROSS CENTRAL AND
EASTERN KS. THE CHARACTER OF THE BOUNDARY WILL BECOME MORE DIFFUSE
WITH SOUTHERN EXTENT, BUT MODEST LOW-LEVEL CONFLUENCE SHOULD STILL
BE ENOUGH TO SUPPORT AFTERNOON THUNDERSTORM DEVELOPMENT. VERTICAL
SHEAR WILL BE WEAK THROUGH THIS ENTIRE CORRIDOR, BUT THERMODYNAMIC
PROFILES WILL FAVOR STRONG DOWNDRAFTS AND THE POTENTIAL FOR ISOLATED
STRONG-SEVERE OUTFLOW GUSTS FOR A FEW HOURS THIS AFTERNOON/EVENING.
..SOUTHEAST
OVERNIGHT CONVECTION HAS RESULTED IN EXTENSIVE CLOUDINESS ACROSS
MUCH OF THE REGION THIS MORNING. EVEN SO, AMPLE LOW-LEVEL MOISTURE
REMAINS IN PLACE AND THE AIRMASS IS EXPECTED TO DESTABILIZE BY THE
EARLY AFTERNOON AMID STRONG HEATING. INITIAL DEVELOPMENT APPEARS
MOST LIKELY NEAR THE WESTWARD PROGRESSING OUTFLOW MOVING ACROSS MS,
WITH ADDITIONAL DEVELOPMENT LATER NEAR A CONVECTIVELY GENERATED
VORTICITY MAXIMUM MOVING ACROSS CENTRAL GA. WIDESPREAD STORMS ARE
ALSO EXPECTED ACROSS FL AS AN UPPER LOW DRIFTS SLOWLY
WEST-NORTHWESTWARD. SHEAR WILL BE WEAK AREAWIDE AND A LARGELY
DISORGANIZED STORM MODE IS ANTICIPATED. SURGING OUTFLOW IS POSSIBLE
WITH THE STRONGEST STORMS, FOSTERING THE POTENTIAL FOR DAMAGING
GUSTS AND ALSO CONTRIBUTING TO ADDITIONAL STORM DEVELOPMENT. SEVERAL
FORWARD-PROPAGATING CLUSTERS ARE POSSIBLE ALTHOUGH THEIR LOCATION,
STRENGTH, AND LONGEVITY ARE UNCERTAIN, PRECLUDING ANY INCREASED
SEVERE PROBABILITIES WITH THIS OUTLOOK.
..MT THIS AFTERNOON/EVENING
A SUBTLE MIDLEVEL TROUGH AND ASSOCIATED/DIFFUSE FRONT WILL MOVE
ACROSS THE NORTHERN ROCKIES THIS AFTERNOON INTO TONIGHT. DEEP
MIXING AND INVERTED-V PROFILES WILL FAVOR SOME POTENTIAL FOR
STRONG-SEVERE OUTFLOW GUSTS WITH SCATTERED HIGH-BASED THUNDERSTORMS
ALONG AND AHEAD OF THE DIFFUSE FRONT THIS AFTERNOON INTO THIS
EVENING.
..OH VALLEY INTO THE MID-ATLANTIC THIS AFTERNOON
SCATTERED THUNDERSTORMS ARE EXPECTED AGAIN THIS AFTERNOON AS THE
AIRMASS DESTABILIZES AMID STRONG DAYTIME HEATING AND AMPLE LOW-LEVEL
MOISTURE. RESIDUAL BOUNDARIES FROM PRIOR CONVECTION, AND TERRAIN
CIRCULATIONS WILL ACT AS FAVORED AREAS FOR INITIATION. VERTICAL
SHEAR WILL BE WEAK, BUT STEEP LOW-LEVEL LAPSE RATES AND
PRECIPITATION LOADING COULD SUPPORT ISOLATED WIND DAMAGE WITH
DOWNBURSTS FROM MID AFTERNOON INTO THE EVENING.
..MOSIER/WENDT.. 06/26/2025
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