888
ACUS01 KWNS 250601
SWODY1
SPC AC 250600
DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
0100 AM CDT SAT OCT 25 2025
VALID 251200Z - 261200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
TEXAS AND LOUISIANA...
..SUMMARY
SCATTERED SEVERE THUNDERSTORMS WITH A TORNADO THREAT, LARGE HAIL AND
SEVERE WIND GUSTS ARE POSSIBLE THIS AFTERNOON AND EVENING FROM
CENTRAL TEXAS EASTWARD INTO THE LOWER MISSISSIPPI VALLEY. VERY LARGE
HAIL WILL BE POSSIBLE ACROSS PARTS OF THE MIDDLE TEXAS COASTAL
PLAIN. A COUPLE OF SEVERE GUSTS OR A BRIEF TORNADO ARE ALSO POSSIBLE
OVER PARTS OF THE PACIFIC NORTHWEST.
..WESTERN GULF STATES
A MID-LEVEL LOW WILL MOVE EASTWARD INTO THE SOUTHERN PLAINS TODAY,
AS AN ASSOCIATED JET STREAK TRANSLATES EASTWARD THROUGH THE BASE OF
THE SYSTEM. AHEAD OF THE SYSTEM, DIFFLUENT SOUTHWESTERLY MID-LEVEL
FLOW WILL BE IN PLACE OVER MUCH OF THE WESTERN GULF COAST STATES. A
LINEAR MCS WILL BE ONGOING AT THE START OF THE PERIOD ACROSS
SOUTHEAST TEXAS. A TORNADO AND WIND-DAMAGE THREAT WILL EXIST WITH
THE MORE INTENSE SEGMENTS OF THE LINE. THE SEVERE THREAT WILL
CONTINUE TO MOVE EASTWARD ACROSS CENTRAL AND SOUTHERN LOUISIANA THIS
MORNING, REACHING THE NEW ORLEANS AREA BY EARLY AFTERNOON.
ALTHOUGH THE LINE WILL STABILIZE THE AIRMASS OVER MUCH OF LOUISIANA,
MODERATE INSTABILITY IS EXPECTED TO REDEVELOP IN ITS WAKE OVER THE
TEXAS COASTAL PLAIN, WHERE MLCAPE IS FORECAST TO REACH THE 1500 TO
2500 J/KG RANGE BY AFTERNOON. ALONG THE WESTERN EDGE OF THE STRONGER
INSTABILITY, LOW-LEVEL CONVERGENCE WILL AID SCATTERED CONVECTIVE
INITIATION THIS AFTERNOON ACROSS EASTERN PARTS OF THE TEXAS HILL
COUNTRY AND OVER THE MIDDLE TEXAS COASTAL PLAIN. RAP FORECAST
SOUNDINGS LATE THIS AFTERNOON FROM SAN ANTONIO TO HOUSTON HAVE 0-6
KM SHEAR AROUND 50 KNOTS WITH 700-500 MB LAPSE RATES NEAR 7 C/KM.
THIS SHOULD SUPPORT SUPERCELLS WITH LARGE HAIL. THE MORE INTENSE
SUPERCELLS COULD PRODUCE HAILSTONES GREATER THAN 2 INCHES IN
DIAMETER.
IN ADDITION, 0-3 KM STORM RELATIVE-HELICITY IS FORECAST TO BE IN THE
200 TO 250 M2/S2 RANGE OVER THE MIDDLE TEXAS COASTAL PLAIN
SUGGESTING THAT A FEW TORNADOES WILL BE POSSIBLE. A POTENTIAL WILL
EXIST FOR A STRONG TORNADO, ALTHOUGH THIS REMAINS UNCERTAIN. THE
STORMS ARE EXPECTED TO CONGEAL INTO A LINEAR CONVECTIVE SYSTEM BY
EARLY EVENING. A POTENTIAL FOR DAMAGING WIND GUSTS WILL EXIST ALONG
THE LEADING EDGE OF THE LINE, WITH THE THREAT CONTINUING INTO THE
EARLY OVERNIGHT PERIOD, ALONG AND NEAR THE COAST OF SOUTHERN
LOUISIANA.
..PACIFIC NORTHWEST
A MID-LEVEL TROUGH, AND AN ASSOCIATED PLUME OF MOISTURE, WILL MOVE
EASTWARD INTO THE PACIFIC NORTHWEST TODAY. STRONG LARGE-SCALE ASCENT
WILL BE FAVORABLE FOR THUNDERSTORM DEVELOPMENT ALONG THE COAST OF
WASHINGTON AND OREGON. A BRIEF TORNADO AND MARGINALLY SEVERE WIND
GUSTS WILL BE POSSIBLE AS CELLS MOVE INLAND NEAR THE COAST. FURTHER
EAST INTO PARTS OF SOUTHEAST WASHINGTON AND FAR NORTHEAST OREGON,
THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE LATE THIS AFTERNOON AS A
LOW-LEVEL JET STREAK MOVES ACROSS THE REGION. IN THIS AREA, LAPSE
RATES WILL BE STEEP AND FLOW WILL BE STRONG SUGGESTING THAT AN
ISOLATED WIND-DAMAGE THREAT WILL BE POSSIBLE.
..BROYLES/WENDT.. 10/25/2025
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