691
FXUS61 KPBZ 181626
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1226 PM EDT SAT JUL 18 2026
WHAT HAS CHANGED
SEVERE STORMS EXPECTED TODAY BETWEEN 5PM AND 10PM WITH A PASSING
COLD FRONT; DAMAGING WINDS THE MAIN THREAT. FLOOD WATCH ISSUED
FOR THE RIDGES AND ADJACENT LOWLANDS OF WESTERN PA AND NORTHERN
WV, WHERE THE HIGHEST RAINFALL AMOUNTS ARE EXPECTED DUE TO
TRAINING THUNDERSTORMS.
KEY MESSAGES
1) DAMAGING WIND GUSTS POSSIBLE IN THUNDERSTORMS THIS EVENING
ALONG A CROSSING COLD FRONT
2) ANOTHER LOW PRESSURE SYSTEM EXPECTED TO RETURN THUNDERSTORMS
AND SEVERE WEATHER CHANCES ON TUESDAY
DISCUSSION
KEY MESSAGE 1...
A COLD FRONT, CURRENTLY MOVING ACROSS CENTRAL MICHIGAN, IS
EXPECTED TO REACH OUR REGION LATE THIS EVENING. AS THE FRONT
APPROACHES, A SQUALL LINE IS EXPECTED TO DEVELOP NEAR LAKE ERIE
AND TRACK SOUTH. DAMAGING STRAIGHT-LINE WINDS WILL BE THE
PRIMARY HAZARD. SECONDARY THREATS INCLUDE QUARTER SIZED HAIL,
BRIEF EMBEDDED TORNADOES ALONG THE COLD FRONT, AND LOCALLY HEAVY
RAINFALL.
THE STORM PREDICTION CENTER HAS PLACED AREAS NORTH OF INTERSTATE
70 IN AN ENHANCED RISK (3/5) FOR SEVERE WEATHER, WHERE THE
ORIENTATION OF THE WIND SHEAR RELATIVE TO THE FRONT IS MOST
FAVORABLE FOR PRODUCING WIDESPREAD DAMAGING STRAIGHT-LINE WINDS.
NUMEROUS COMMUNITIES COULD EXPERIENCE DOWNED TREES AND
SCATTERED POWER OUTAGES THIS EVENING AS THE SQUALL LINE MOVES
THROUGH.
AHEAD OF THE APPROACHING COLD FRONT, A FEW DISCRETE
THUNDERSTORMS MAY DEVELOP. IF THESE STORMS PRODUCE UPDRAFTS THAT
RAPIDLY STRENGTHEN THEY COULD GENERATE STRONG, ICE-LOADED
DOWNDRAFTS CAPABLE OF PRODUCING SEVERE WIND GUSTS.
THE HIGHER ELEVATIONS OF WESTERN PA AND NORTHERN WV, AND THEIR
ADJACENT LOWLANDS, ARE STILL FORECAST TO RECEIVE THE HEAVIEST
RAINFALL ACCUMULATIONS OF THE DAY PER LATEST CONVECTIVE ALLOWING
MODELS, PRIMARILY DUE TO A COMBINATION OF AFTERNOON ROUNDS OF
THUNDERSTORMS AND TRAINING ALONG THE SLOWLY-ADVANCING EVENING
COLD FRONT. THE WEATHER PREDICTION CENTER HAS UPGRADED THEIR
EXCESSIVE RAINFALL OUTLOOK TO A SLIGHT RISK (LEVEL 2 OUT OF 4)
FOR THESE AREAS, AND A FLOOD WATCH HAS BEEN ISSUED UNTIL
MIDNIGHT TONIGHT.
THE PROBABILITY OF THUNDERSTORMS IS EXPECTED TO DECREASE BETWEEN
9PM AND 11PM THIS EVENING AS THE COLD FRONT EXITS SOUTH INTO
CENTRAL WEST VIRGINIA.
KEY MESSAGE 2...
MACHINE LEARNING GUIDANCE HAS REMAINED CONSISTENT IN SIGNALING
THAT A LOW PRESSURE SYSTEM TRACKING ACROSS THE GREAT LAKES ON
TUESDAY WILL BRING ANOTHER THREAT OF SEVERE STORMS TO THE
REGION. THE STORM PREDICTION CENTER (SPC) HAS OUTLINED THE
ENTIRE FORECAST DOMAIN IN A 15% SEVERE WEATHER RISK. DAMAGING
WIND GUSTS AND TORNADOES APPEAR TO THE BE THE PRIMARY HAZARD AS
STRONG WIND SHEAR ACCOMPANIES THIS LARGE-SCALE SYSTEM.
IN ADDITION TO THE SEVERE WEATHER THREAT, THERE IS ALSO THE
POTENTIAL FOR TRAINING SHOWERS AND STORMS WITH A POTENTIAL
MESOSCALE CONVECTION SYSTEM (MCS) ACROSS THE OHIO RIVER VALLEY.
RAINFALL TOTALS COULD RANGE BETWEEN 1.5-2 INCHES IN A SHORT
PERIOD OF TIME AND RESULT IN FLASH FLOODING.
AVIATION /16Z SATURDAY THROUGH WEDNESDAY/
MORNING TSRA IS FLEETING EASTWARD AT THIS TIME AND WILL BRING
VCTS CONDITIONS TO DUJ AND LBE BETWEEN 12-13Z BEFORE CLEARING
OUT.
IFR-MVFR VIS CONTINUES IN SMOKE THIS MORNING. ALTHOUGH UPPER-
LEVEL WINDS ARE BEGINNING TO CLEAR SMOKE NOTICEABLY FROM THE
REGION, SMOKE TRAPPED UNDERNEATH OUR INVERSION LAYER WILL
CONTINUE TO BE AN ISSUE UNTIL WE REMOVE THE INVERSION AND BEGIN
TO MIX CLOSER TO MIDDAY. VIS SHOULD GRADUALLY IMPROVE LATE THIS
MORNING AND THEN MORE READILY BY MIDDAY.
VFR CONDITIONS WITH ISOLATED SHOWERS AND STORMS ARE EXPECTED
BETWEEN 16Z TO 18Z DUE TO BROAD ASCENT PROVIDED BY AN UPPER-
LEVEL SHORTWAVE TROUGH. WITHIN THESE STORMS, VIS COULD DROP
BETWEEN 1SM TO 3SM BRIEFLY. THESE STORMS COULD BRING DAMAGING
WIND GUSTS AND CARRY A LOW END TORNADO RISK.
BETWEEN 20Z AND 23Z THE COLD FRONT IS EXPECTED TO ADVANCE SOUTH
OF LAKE ERIE AND IMPACT THE NORTHERN TERMINALS FIRST. TEMPOS
CONTINUE FOR STRONG WIND GUSTS IN HEAVY THUNDERSTORMS ALONG THE
FRONT.
OUTLOOK... TEMPORARY VISIBILITY RESTRICTIONS ARE POSSIBLE
SUNDAY MORNING BEFORE VFR RETURNS SUNDAY AND MONDAY UNDER HIGH
PRESSURE. RESTRICTIONS RETURN IN SHOWERS AND THUNDERSTORMS ON
TUESDAY WITH A COLD FRONT.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR PAZ015-016-022-
073>078.
OH...NONE.
WV...FLOOD WATCH UNTIL MIDNIGHT EDT TONIGHT FOR WVZ511-512.
AIR QUALITY ALERT UNTIL MIDNIGHT EDT TONIGHT FOR WVZ001>004-
012-021-509>514.
DISCUSSION...CERMAK/HEFFERAN
AVIATION...HEFFERAN/AK
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