945
FXUS61 KPBZ 210548
AFDPBZ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
1248 AM EST WED JAN 21 2026
WHAT HAS CHANGED
A WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR THE NORTHERN
COUNTIES FOR SNOWFALL. BETTER CONFIDENCE IN A PROLONGED COLD
EVENT FRIDAY THROUGH THE WEEKEND.
KEY MESSAGES
1) RAIN AND SNOW RETURN WEDNESDAY THROUGH THURSDAY WITH A
PASSING TROUGH AND ASSOCIATED FRONT.
2) SNOW POSSIBLE SATURDAY INTO SUNDAY. TOTALS DEPENDENT ON THE
NORTHERN EXTENT OF THE LOW PRESSURE TRACK.
3) CONSECUTIVE COLD MEAN DAILY TEMPERATURES STARTING FRIDAY
THROUGH THE FIRST HALF OF NEXT WEEK COULD NEGATIVELY IMPACT
REGIONAL INFRASTRUCTURE, SUCH AS FROZEN PIPES, AND PUTTING A
STRAIN ON THE ENERGY GRID.
DISCUSSION
KEY MESSAGE 1... RAIN AND SNOW RETURN WEDNESDAY THROUGH THURSDAY
MORNING WITH A PASSING TROUGH AND ASSOCIATED FRONT.
ANOTHER TROUGH AND ASSOCIATED FRONT WITHIN THE NORTHWEST FLOW
WILL CROSS THE GREAT LAKES ON WEDNESDAY INTO WEDNESDAY NIGHT,
BRINGING ANOTHER ROUND OF SNOW NORTH OF I-80, AND A COMBO OF RAIN
AND SNOW FARTHER SOUTH OF I-80 WITH WARM ADVECTION AHEAD OF THE
FRONT. THE WARM ADVECTION HOWEVER WILL BE SHORT LIVED AND MAY
ONLY ALLOW A BRIEF PERIOD OF RAIN SOUTH OF I-80. FURTHER SOUTH,
SOUTH OF I-70 WILL HAVE A LONGER DURATION OF RAIN. 2 TO 5
INCHES WILL BE POSSIBLE ACROSS NORTHERN COUNTIES (HIGHER VALUES
FROM SOUTH TO NORTH), MAINLY ALONG AND NORTH OF I-80. OVERALL
GUIDANCE HAS TRENDED LOWER WITH AMOUNTS, BUT ADVISORY LEVELS ARE
STILL POSSIBLE SO HAVE MAINTAINED MENTION OF THAT IN THE HWO.
THE NBM PROBABILITIES WILL FEATURE AROUND 50% TO 70% PROBS OF 3
INCHES OR MORE ALONG THE NORTHERN COUNTIES AND AS SUCH A WINTER
WEATHER ADVISORY HAS BEEN ISSUED.
ANOTHER CONSIDERATION IS FOR AREAS THAT SEE RAIN DURING THE DAY
ON WEDNESDAY WHERE SURFACE TEMPERATURES MAY STILL BE BELOW
FREEZING GIVEN PREVIOUS COLD TEMPERATURES. THIS WILL NEED TO BE
MONITORED STILL. AS WELL, THE HIGHER TERRAIN IN TUCKER COUNTY
MAY POTENTIALLY BE IMPACTED BY A ROUND OF FREEZING RAIN/FREEZING
DRIZZLE. THIS WILL ALSO NEED MONITORING.
KEY MESSAGE 2... SNOW POSSIBLE SATURDAY INTO SUNDAY. TOTALS
DEPENDENT ON THE NORTHERN EXTENT OF THE LOW PRESSURE TRACK.
THIS WEEKEND THERE IS A LOW PRESSURE SYSTEM FORECAST TO DEVELOP TO
THE SOUTH AND MOVE EAST OF THE AREA. THERE ARE DIFFERENT OUTCOMES
RESULTING FROM THE UNCERTAINTY IN THE STORM TRACK.
(1) THE FIRST OUTCOME WOULD BE THE LOW DEVELOPING AND STAYING TO THE
SOUTH, MAINLY TRACKING THROUGH THE SOUTHEASTERN U.S. THIS WOULD
RESULT IN LOW SNOW ACCUMULATIONS (<1") FOR OUR REGION WHICH HAS A
20% CHANCE OF OCCURING.
(2) THE SECOND OUTCOME WOULD BE THE LOW STAYING SOUTH BEFORE CURVING
NORTHWARD AS IT APPROACHES THE MID-ATLANTIC REGION. THERE WOULD BE
MEASURABLE SNOW ACCUMULATION FOR THE REGION WITH A LIKELY RANGE
BETWEEN 1" IN THE NORTH TO 6" IN PARTS OF NORTHERN WEST VIRGINIA.
CURRENTLY, THIS APPEARS TO BE THE MOST LIKELY OUTCOME WITH A 50%
CHANCE OF OCCURRENCE.
(3) THE THIRD OUTCOME WOULD BE THE LOW CURVING NORTHWARD SOONER AND
TRACKING ALONG THE APPALACHIAN MOUNTAIN RIDGES BEFORE REFORMING
OFFSHORE IN THE ATLANTIC. THIS WOULD RESULT IN THE HIGHEST POSSIBLE
ACCUMULATION WITH >6" LIKELY AND A POSSIBLE MAXIMUM ACCUMULATION OF
UP TO 12" (IN NORTHERN WV). THIS IS THE LEAST LIKELY OUTCOME WITH A
20% CHANCE OF OCCURRENCE.
WE WILL CONTINUE TO MONITOR THIS STORM THROUGHOUT THE WEEK AND
PROVIDE UPDATES ALONG THE WAY.
KEY MESSAGE 3... CONSECUTIVE COLD MEAN DAILY TEMPERATURES STARTING
FRIDAY THROUGH THE FIRST HAVE OF NEXT WEEK COULD NEGATIVELY IMPACT
REGIONAL INFRASTRUCTURE, SUCH AS FROZEN PIPES, AND PUTTING A STRAIN
ON THE ENERGY GRID.
MODEL GUIDANCE CONTINUES TO SIGNAL A RELATIVELY LONG PERIOD OF WELL
BELOW NORMAL TEMPERATURES FROM FRIDAY INTO LATE NEXT WEEK. EMPIRICAL
DATA SUGGESTS INFRASTRUCTURE PROBLEMS (FROZEN PIPES, ETC), START TO
OCCUR AFTER THE MEAN DAILY TEMPERATURE RUNS -12F BELOW NORMAL FOR 48
HOURS OR MORE. FOR THIS TIME OF YEAR IN THE PGH AREA THIS IS
APPROXIMATELY A DAILY MEAN TEMPERATURE OF 15F.
THROUGH TUESDAY, HIGHS IN THE UPPER TEENS/LOW 20S AND LOWS NO HIGHER
THAN 10F ARE LIKELY FOR A MAJORITY OF THE AREA. THIS WOULD RESULT IN
THE DAILY MEAN TEMPERATURE REMAINING BELOW 15F . THERE IS INCREASED
UNCERTAINTY LATER INTO NEXT WEEK. A LOT CAN CHANGE BEING THAT FAR
OUT, BUT IT WILL BE MONITORED.
ADDITIONALLY, WE MAY SEE RELATIVELY FAST ICE FORMATION ON AREA
RIVERS GIVEN THE AVERAGE DAILY TEMPERATURES THAT ARE FORECAST.
AVIATION /06Z WEDNESDAY THROUGH SUNDAY/
KEY MESSAGES...
1) VFR THROUGH MOST OF THE MORNING.
2) MVFR/IFR CIG/VIS RESTRICTIONS WITH SNOW AFTER 18Z.
3) TIGHTENING PRESSURE GRADIENT BRINGS GUSTY SOUTH/SOUTHWEST
WINDS.
------------------------------------------------------------
HIGH PRESSURE WILL KEEP THE AREA DRY WITH LIGHT WINDS THROUGH
OVERNIGHT HOURS. HIGH CLOUDS BEGIN TO MOVE IN AND CEILINGS
GRADUALLY LOWER THROUGH THE MORNING AHEAD OF THE NEXT
APPROACHING LOW PRESSURE SYSTEM. SNOW CHANCES INCREASE BY LATE
MORNING AND AFTERNOON ACROSS MUCH OF THE AREA AS CEILINGS DROP
TO MVFR/IFR. RAIN MAY MIX IN AT TIMES, PRIMARILY ALONG AND SOUTH
OF I-70. VISIBILITIES MAY DROP AS LOW AS IFR/LIFR INSIDE
PRECIPITATION, ESPECIALLY DURING INSTANCES OF HEAVIER SNOW.
SOUTH-SOUTHWEST WINDS INCREASE AFTER SUNRISE, WITH GUSTS IN THE
20-25 KNOT RANGE. GUSTY WINDS WILL LINGER THROUGH THE REMAINDER
OF THE PERIOD.
OUTLOOK... RESTRICTIONS AND SNOW LINGER INTO THURSDAY WITH THE
APPROACH AND PASSAGE OF A COLD FRONT. CIG RESTRICTIONS ARE STILL
POSSIBLE FRIDAY AND SATURDAY UNDER COLD NW FLOW AND BROAD UPPER
TROUGHING.
PBZ WATCHES/WARNINGS/ADVISORIES
PA...WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 10 AM EST
THURSDAY FOR PAZ007>009-015-016-077-078.
OH...NONE.
WV...NONE.
DISCUSSION...SHALLENBERGER/LUPO
AVIATION...CERMAK/RACKLEY
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