128
FXUS61 KPBZ 170626
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
226 AM EDT WED JUN 17 2026
WHAT HAS CHANGED
THE SEVERE WEATHER POTENTIAL CONTINUES TONIGHT INTO EARLY
THURSDAY MORNING. THURSDAY HAS TRENDED DRIER WITH THE AFTERNOON
SEVERE POTENTIAL SHIFTING SOUTHWARD.
KEY MESSAGES
1) SCATTERED SHOWERS AND GUSTY THUNDERSTORMS EARLY THIS
MORNING, THEN DRY
2) SEVERE WEATHER POTENTIAL TONIGHT INTO EARLY THURSDAY, WITH A
MORE LIMITED POTENTIAL SOUTH OF PIT THURSDAY AFTERNOON. GUSTY
WIND POTENTIAL CONTINUES THURSDAY
3) DRY FRIDAY AND SATURDAY, WITH RAIN CHANCES INCREASING AGAIN
SUNDAY
DISCUSSION
KEY MESSAGE 1...
A SHORTWAVE CONTINUES TO TRACK EAST ACROSS THE REGION EARLY THIS
MORNING. SHOWERS AND A FEW GUSTY THUNDERSTORMS WILL CONTINUE AS
THE WAVE CROSSES. INSTABILITY IS MINIMAL, WITH A MU CAPE 250
J/KG OR LESS, THOUGH THE CONVECTION IS ON THE LEADING EDGE OF A
LOW LEVEL JET, WHICH WAS MAINTAINING THE SHOWERS/STORMS. THIS
WAVE SHOULD EXIT THE REGION AROUND SUNRISE, WITH SHOWERS AND
THUNDERSTORMS ENDING.
FLAT SHORTWAVE RIDGING AND A STRONG CAP SHOULD RESULT IN DRY
WEATHER FOR THE REMAINDER OF THE DAY, WITH HIGH TEMPERATURES
NEAR SEASONABLE LEVELS.
KEY MESSAGE 2...
THE NEXT SHORTWAVE TROUGH IS EXPECTED TO ADVANCE ACROSS THE
MIDWEST TODAY INTO THIS EVENING, AS SURFACE LOW DEEPENS AHEAD OF
IT. A SIGNIFICANT SEVERE WEATHER OUTBREAK IS EXPECTED TO BE
ONGOING TO OUR WEST THIS AFTERNOON AND EVENING IN THE WARM
SECTOR, AS A STRONG LOW AND MID LEVEL JET SETS UP ACROSS THE
REGION. THIS JET IS EXPECTED TO STRENGTHEN AS IT TRACKS ACROSS
THE UPPER OHIO VALLEY REGION TONIGHT. WINDS AT 850MB ARE PROGGED
FROM 55-65 KT, WITH SIMILAR WIND AT 700MB. OVERALL INSTABILITY
IS PROGGED TO DECREASE OVERNIGHT AS THE CONVECTION MOVES EAST
ALONG A PRE FRONTAL TROUGH, THOUGH ENSEMBLE MU CAPE STILL SHOWS
AROUND 500 J.KG AVAILABLE. SOME CAMS INDICATE ENOUGH MIXING WITH
THE STRONG FLOW ALOFT TO MAINTAIN A SIMILAR SURFACE BASED CAPE
AS WELL.
EVEN WITH THE LOWERING LEVELS OF INSTABILITY, THE STRONG FLOW
ALOFT SHOULD RESULT IN 0-6KM SHEAR FROM 50-70KT. DIRECTIONAL
SHEAR IS ALSO EXPECTED, RESULTING IN CURVED HODOGRAPHS. THE
HIGHEST POTENTIAL FOR SEVERE WEATHER IS EXPECTED TO BE ACROSS
OHIO, WHERE THE GREATEST INSTABILITY IS PROGGED. THERE REMAINS
SOME QUESTION ON HOW FAR EAST THE SEVERE POTENTIAL WILL
CONTINUE. THINK SOME CAMS WEAKEN THE CONVECTION TOO QUICKLY
GIVEN THE ENVIRONMENT. THE LATEST CONVECTIVE OUTLOOK FROM THE
STORM PREDICTION CENTER CONTINUES TO CARRY THE SLIGHT RISK FOR
SEVERE STORMS INTO EASTERN OHIO, WITH THE MARGINAL INTO WESTERN
PA AND NORTHER WV. THIS COULD BE ADJUSTED THROUGH THE DAY
DEPENDING ON THE CONVECTIVE DEVELOPMENT TO THE WEST AND THE
AMOUNT OF DESTABILIZATION THAT OCCURS ACROSS THE UPPER OHIO
VALLEY REGION. AT THIS TIME, DAMAGING WIND APPEARS TO BE THE
MAIN HAZARD, THOUGH ISOLATED TORNADOES AND LARGE HAIL WILL ALSO
BE POSSIBLE. THE POTENTIAL FOR FLOODING CONTINUES TO LOWER WITH
A MORE PROGRESSIVE STORM MODE.
THE INITIAL CONVECTION SHOULD EXIT THE REGION THURSDAY MORNING
WITH THE PREFRONTAL TROUGH. THE SURFACE LOW WILL CONTINUE IT'S
NORTHEASTWARD TRACK TO EASTERN ONTARIO, AND WILL PULL A COLD
FRONT ACROSS THE UPPER OHIO VALLEY REGION. DRY ADVECTION AND
CAPPING WARMTH ALOFT WILL LIKELY PRECLUDE ADDITIONAL
THUNDERSTORMS ACROSS MOST OF THE AREA FOR THE REST OF THE DAY.
THE EXCEPTION WILL BE MAINLY SOUTH OF I-70, WHERE SOME
ADDITIONAL CONVECTION IS POSSIBLE IN THE AFTERNOON IN THE
VICINITY OF THE COLD FRONTAL BOUNDARY. SPC HAS TRIMMED MORE OF
THE AREA OUT OF THE SLIGHT RISK FOR SEVERE STORMS, WHICH SEEMS
REASONABLE GIVEN THE RECENT MODEL TRENDS. DAMAGING WIND WOULD BE
THE MAIN THREAT FOR ANY STORMS THAT DEVELOP, WITH THE CONTINUED
STRONG FLOW ALOFT.
MIXING WILL LIKELY BRING DOWN STRONG WIND GUSTS EVEN OUTSIDE OF
CONVECTION ON THURSDAY. BUFKIT MOMENTUM TRANSFER, AND MODEL
ENSEMBLE PROBABILITIES OF ADVISORY LEVEL GUSTS, HAVE DECREASED
SOME IN RECENT MODEL RUNS. MAINTAINED GUSTY WINDS IN THE GRIDS,
WITH SUB ADVISORY LEVELS AT THIS TIME. THERE IS STILL A
POTENTIAL THAT A WIND ADVISORY WILL BE NEEDED, BUT DO NOT HAVE
THE CONFIDENCE IN ADVISORY LEVEL GUSTS (GREATER THAT 45 MPH) AT
THIS TIME.
KEY MESSAGE 3...
DRY WEATHER RETURNS FRIDAY AND SATURDAY AS HIGH PRESSURE BUILDS
ACROSS THE REGION. MORE WIDESPREAD RAIN CHANCES RETURN SUNDAY
INTO MONDAY AS LOW PRESSURE TRACKS ACROSS THE REGION.
AVIATION /06Z WEDNESDAY THROUGH SUNDAY/
A CROSSING SHORTWAVE, LOW LEVEL JET, AND MINIMAL INSTABILITY
WILL MAINTAIN SHOWERS AND THUNDERSTORMS TRACKING ACROSS THE
REGION EARLY THIS MORNING. THIS ACTIVITY SHOULD QUICKLY MOVE
EAST OF THE REGION BY SUNRISE AS THE SHORTWAVE EXITS. OTHERWISE,
VFR IS EXPECTED THE REST OF THE DAYTIME HOURS UNDER SHORTWAVE
RIDGING AND STRONG CAPPING ALOFT. EXPECT SCATTERED CUMULUS AND
INCREASING HIGH CLOUDS THROUGH THE DAY AHEAD OF THE NEXT
APPROACHING SHORTWAVE. MIXING AND INCREASING FLOW ALOFT SHOULD
RESULT IN GUSTY SW WIND TODAY AS WELL.
A DEEPENING SURFACE LOW IS EXPECTED TO TRACK ACROSS THE MIDWEST
INTO SOUTHERN ONTARIO TONIGHT INTO THURSDAY. A PREFRONTAL
TROUGH, STRONG LOW LEVEL JET, AND INSTABILITY SHOULD RESULT IN
MVFR/LOCAL IFR CONDITIONS AS SHOWERS AND THUNDERSTORMS
OVERSPREADING THE REGION TONIGHT. SOME OF THESE STORMS COULD BE
SEVERE, WITH A STRONG LOW-MID LEVEL JET IN PLACE ALOFT.
OUTLOOK...
RESTRICTIONS ARE EXPECTED TO CONTINUE INTO THURSDAY MORNING AS
THE SHOWERS AND THUNDERSTORMS GRADUALLY EXIT THE REGION.
SHOWERS AND STORMS COULD REDEVELOP, ESPECIALLY IN THE AFTERNOON,
SOUTH OF A ZZV-LBE LINE AS THE LOW'S COLD FRONT DROPS SOUTH
ACROSS THE REGION. IN ADDITION, STRONG WSW WIND COULD GUST FROM
30-40 KT THROUGH THE DAY AS THE STRONG WINDS ALOFT MIX DOWN.
DIMINISHING WIND IS EXPECTED THURSDAY NIGHT, WITH VFR
CONDITIONS THEN RETURNING THROUGH SATURDAY UNDER BUILDING HIGH
PRESSURE. RESTRICTIONS IN SHOWERS AND THUNDERSTORMS ARE
POSSIBLE SUNDAY WITH APPROACHING LOW PRESSURE.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...NONE.
OH...NONE.
WV...NONE.
DISCUSSION...WM
AVIATION...WM
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page