559
FXUS61 KPBZ 101755
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
155 PM EDT SAT OCT 10 2026
WHAT HAS CHANGED
WIND ADVISORY EXPANDED INTO THE LOWLAND ZONES OF WESTMORELAND,
FAYETTE, AND MONONGALIA COUNTIES WITH DOWNSLOPING WIND
POTENTIAL.
KEY MESSAGES
1) A WIND ADVISORY REMAINS IN EFFECT FOR THE HIGH TERRAIN AND
IMMEDIATELY DOWNSLOPE AND DOWNWIND OF THE RIDGE-LINE. WIND
GUSTS AS HIGH AS 45-55MPH REMAIN POSSIBLE IN THE ADVISORY AREA.
2) A POTENT TROUGH IS POSSIBLE LATE-WEEK AND INTO NEXT WEEKEND
WHICH MAY BRING WINDS AND A COOL-DOWN.
DISCUSSION
KEY MESSAGE 1...
THE REMNANTS OF ISAIAS ARE STILL FORECAST TO TREK ACROSS THE
AREA BEGINNING TONIGHT, AND LASTING THROUGH MONDAY MORNING.
IT WILL LIKELY BRING RAIN AND SOME WINDS WITH IT.
THE FIRST IMPACTS FROM WIND WILL RAMP UP IN THE PENNSYLVANIA
RIDGES THROUGH THE AFTERNOON AND INTO TONIGHT AS LOW PRESSURE
APPROACHES FROM THE SOUTHWEST. THIS WILL FORCE RIDGE-
PERPENDICULAR SOUTH-EASTERLIES IN THE LAUREL MOUNTAINS AND HIGH
TERRAIN OF WEST VIRGINA, WITH MOST RECENT MODEL GUIDANCE HAVING
THE RIDGETOPS GUSTING UPWARDS OF 40MPH AFTER 8PM AS FLOW
ACCELERATES UP AND OVER THE LAUREL HIGHLANDS.
OVERNIGHT, THE LOW WILL APPROACH AND THE SFC-850MB LAYER IS
EXPECTED TO STABILIZE AROUND THE RIDGE-LINES, WHICH IS EXPECTED
TO BOTH ACCELERATE FLOW AT THE RIDGETOPS AS HIGH AS 45MPH TO
55MPH, BUT ALSO MAKE THERMODYNAMIC PROFILES MORE CONDUCIVE FOR
DOWNSLOPING IMMEDIATELY WEST OF THE LAUREL MOUNTAINS (WITH
GUSTS UP TO 45MPH TO 55MPH MOST POSSIBLE FOR EASTERN SUBURBS OF
MORGANTOWN, UNIONTOWN, CONNELLSVILLE, EASTERN SUBURBS OF MOUNT
PLEASANT, AND DERRY). THERE IS STILL A QUESTION OF IF THIS
OCCURS OR NOT BASED ON THE EXACT THERMODYNAMICS, BUT THOUGH THE
RISK WAS PRUDENT ENOUGH TO UPGRADE, PARTICULARLY WITH THE
WORST- CASE SCENARIO OF WINDS NEAR UNIONTOWN OF 60MPH. THE OLD
WIND ADVISORY ENCOMPASSED ALL HIGH TERRAIN. LOWLAND ZONES WERE
ADDED IN WESTMORELAND, FAYETTE, AND MONONGALIA, BUT IN REALITY,
THE GUSTIEST WINDS WILL BE FAIRLY CONFINED TO THE AFOREMENTIONED
AREAS.
INTO SUNDAY, THE LOW WILL DEPART AND SURFACE PROFILES WILL
BECOME LESS STABLE IN THE SFC-850MB LAYER, MAKING BOTH SYNOPTIC
AND DOWNSLOPE WIND LESS LIKELY BY THE 11AM TO 2PM WINDOW. THIS
IS ALSO THE END TIME FOR THE WIND ADVISORY.
RAIN AMOUNTS, AND THE LOCATION OF HEAVIEST RAIN HAVE BECOME
MORE CONFIDENT. DOWNSLOPING EFFECTS WITHIN AND ROUGHLY 50 MILES
WEST OF THE RIDGES WILL ACTUALLY TAMPER RAIN AMOUNTS, WITH MOST
LIKELY TOTALS LESS THAN 0.75" IN WESTERN PA AND NORTHERN WV,
WITH A WORST-CASE SCENARIO OF 1.25".
RAINFALL AMOUNTS WILL LIKELY BE MORE WIDESPREAD INTO EASTERN
OHIO AND PARTS OF NORTHWEST PA WITH THE ABSENCE OF DOWNSLOPE
EFFECTS AND THE WARM CONVEYOR BELT WRAPPING AROUND THE NORTH-
SIDE OF THE LOW AND A REGION OF MID-LEVEL FRONTOGENESIS AND
GENERALIZED ASCENT. EVEN THEN, RAINFALL AMOUNTS ARE MOST LIKELY
IN THE RANGE OF 1" TO 1.75", WITH WORST-CASE LOCALIZED AMOUNTS
OF UP TO 2" TO 3". HIRES GUIDANCE CONTINUES TO HINT AT THE
POTENTIAL FOR A NARROW AXIS OF UP TO 2" IN 6HR, BUT EVEN THEN
THOSE AMOUNTS ARE STILL BELOW FLASH FLOOD GUIDANCE GIVEN THE
EXTENDED DRY PERIOD. NONETHELESS, AREAL FLOODING WHERE RAIN IS
MAXIMIZED IS POSSIBLE, BUT LOW PROBABILITY. OCCASIONAL URBAN
ISSUES AND LEAVES CLOGGING STORM DRAINS MAY OCCUR.
KEY MESSAGE 2...
THERE IS INCREASING CONFIDENCE OF AN EASTERN TROUGH INTO LATE-
WEEK. WHILE THERE IS STILL NOTABLE TIMING AND AMPLITUDE
UNCERTAINTY, ANOTHER CHANCE OF SOME GUSTY WINDS AND WILL NEED TO
BE MONITORED, ALONG WITH A COOLER TEMPERATURES. A HIGHER-
AMPLITUDE, MORE WESTERN TROUGH AXIS SCENARIO COULD BRING THE
HIGHEST IMPACTS VIA WINDS OR EVEN THE CHANCE OF THE FIRST
SNOWFLAKES OF THE SEASON VIA LAKE-ENHANCEMENT. THOUGH THERE ARE
STILL NUMEROUS, LOWER IMPACT SCENARIOS (INCLUDING A LOWER
AMPLITUDE OR MORE EASTERN TROUGH AXIS).
AVIATION /18Z SATURDAY THROUGH THURSDAY/
VFR CONDITIONS WILL LIKELY CONTINUE INTO THE LATE EVENING,
AHEAD OF THE REMNANTS OF ISAIAS WITH MID- TO UPPER-LEVEL CLOUDS
OVERSPREADING THE REGION.
THE PROBABILITY OF CIGS AND VIS RESTRICTIONS INCREASES BETWEEN
06Z TO 12Z SUNDAY AS RAIN SHOWERS OVERSPREAD THE REGION FROM
SOUTH TO NORTH. HIGH-RESOLUTION MODELS SUGGEST CIGS QUICKLY
DROPPING TO LOW-MVFR OR HIGH-IFR AS LOW-LEVEL MOISTURE BUILDS
AND AN INVERSION DEVELOPS JUST ABOVE THE SURFACE FROM THE
STRONG VERTICAL WIND PROFILE. LBE AND MGW ARE THE MOST LIKELY TO
KEEP CEILINGS ABOVE IFR DURING THE DAY TOMORROW DUE TO THE
ENHANCED EASTERLY DOWNSLOPING WINDS ALONG THE RIDGE-LINE MIXING
IN SOME DRY AIR. SUNDAY MORNING, WINDS GUSTS WILL LIKELY RANGE
BETWEEN 20KTS-30KTS WITH HIGHER GUSTS NEAR LBE/MGW (UP TO
30KTS-40KTS). WIND WILL BEGIN TO EASE BETWEEN 18Z AND 23Z.
RAIN CHANCES WILL DECREASE FROM WEST TO EAST BETWEEN 21Z SUNDAY
TO 03Z MONDAY AS THE SYSTEM BECOMES AN OPEN WAVE AND VENTURES
EAST. SUNDAY NIGHT, SURFACE WIND WILL CONTINUE TO EASE. WITHOUT
DRY AIR MIXING-IN AT THE SURFACE (ESPECIALLY NEAR LBE AND MGW),
THE HEIGHT OF THE SURFACE INVERSION WILL LOWER RESULTING IN
BRINGING ALL CEILINGS DOWN TO IFR OR LIFR.
OUTLOOK...
VFR CONDITIONS ARE EXPECTED MONDAY AFTERNOON WITH WARM,
SOUTHWEST FLOW DISSOLVING ANY LINGERING LOW-LEVEL CIGS.
A COLD FRONT MAY RETURN RESTRICTIONS LATE TUESDAY.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...WIND ADVISORY FROM 8 PM THIS EVENING TO 2 PM EDT SUNDAY FOR
PAZ073>076-078.
OH...NONE.
WV...WIND ADVISORY FROM 8 PM THIS EVENING TO 11 AM EDT SUNDAY FOR
WVZ509>514.
DISCUSSION...MILCAREK
AVIATION...LUPO
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