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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PITTSBURGH PA
919 PM EDT FRI OCT 24 2014

.SYNOPSIS...
EXCEPT FOR A PASSING SHOWER ON SATURDAY...THE WEATHER WILL BE DRY 
UNTIL TUESDAY NIGHT. DESPITE A BRIEF COOLDOWN ON 
SUNDAY...TEMPERATURES WILL BE ON A WARMING TREND.

&&

.NEAR TERM /THROUGH SATURDAY/...
920 PM UPDATE...AGAIN UPDATED SKY GRIDS FOR CURRENT TRENDS. PATCH
OF LOWER CLOUDS APPROACHING WESTERN CWA. EXPECT THIS TO EXPAND
SOMEWHAT WITH TIME AS DEPICTED ON NAM/RAP MODEL SOUNDINGS. SOME
HIGHER CLOUDS MAY STREAM OVER THE TOP AS WELL AHEAD OF THE
APPROACHING FRONT. LEFT LOW TEMPERATURE FORECAST ALONE FOR THE
MOST PART. THINK TEMPERATURES WILL STILL BE ABLE TO SINK A LITTLE
BIT BELOW LATEST LAMP NUMBERS GIVEN THE DRY AIR IN PLACE...BEFORE
CLOUDS BECOME MORE WIDESPREAD.

STILL DUBIOUS ON PRECIPITATION CHANCES FOR TOMORROW AS THERE IS A
LOT OF DRY AIR TO OVERCOME. STILL...WILL LEAVE SLIGHT CHANCE POPS
ALONG AND ALLOW NEXT SHIFT TO REEVALUATE.  CL

PREVIOUS DISCUSSION...

TRANQUIL WEATHER IS EXPECTED TONIGHT THANKS TO HIGH PRESSURE ACROSS 
THE REGION. CLOUDS WILL INCREASE OVERNIGHT IN ADVANCE OF A COLD 
FRONT CURRENTLY ACROSS THE NORTHERN PLAINS. TEMPERATURES WILL BE AT 
OR SLIGHTLY ABOVE SEASONAL VALUES DUE TO THE INCREASING CLOUD COVER.

CONFLICTED OVER THE PRECIPITATION FORECAST FOR SATURDAY AFTERNOON. 
SYNOPTIC MODELS HAVE CONSISTENTLY SHOWED A SMALL AMOUNT OF PRECIP 
REMAINING NORTH OF PITTSBURGH WITH LIMITED SATURATION IN MODEL 
PROFILES...WHILE 12Z HIGH-RESOLUTION MODELS ALL SHOW A LINE OF 
SHOWERS EXTENDING ACROSS THE ENTIRE FORECAST AREA. DO NOT HAVE THE 
CONFIDENCE IN AMOUNT OF MOISTURE TO GO WITH CHANCE POPS TO THE 
NORTH...BUT ALSO DONT FEEL COMFORTABLE LEAVING SOUTHERN COUNTIES 
DRY. HATE TO BROADBRUSH THE FORECAST...BUT WILL GO WITH SLIGHT 
CHANCE SHOWERS EVERYWHERE. SOUTHWESTERLY WINDS WILL CONTRIBUTE TO 
HIGH TEMPS ON SATURDAY RUNNING ABOUT 5 DEGREES ABOVE NORMAL.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS THE COLD FRONT CROSSES THE AREA SATURDAY NIGHT...CLOUDS WILL BE 
ON A DIMINISHING TREND. RECENT MODEL TRENDS PUSH THE FRONT THROUGH 
SLIGHTLY FASTER...WHICH WOULD ALLOW FOR MORE CLEARING AND CLOSER TO 
NORMAL TEMPERATURES. TEMPERATURES WILL BE NEAR NORMAL ON SUNDAY WITH 
COOLER AIR BEHIND THE FRONT...AND WESTERLY WINDS WILL ALLOW FOR 
CLOUD COVER TO LINGER ALONG THE I-80 CORRIDOR DUE TO LAKE ERIE 
MOISTURE. HIGH PRESSURE MOVING TO THE EAST WILL ALLOW FOR CLEAR 
SKIES SUNDAY NIGHT AND PROBABLY THE COLDEST NIGHT IN THE 7 DAY 
FORECAST. AS HIGH PRESSURE SHIFTS EAST OF THE REGION...SOUTHERLY 
FLOW WILL BRING A RETURN TO ABOVE NORMAL TEMPERATURES ON 
MONDAY...RANGING FROM THE MID 60S TO MID 70S.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A RIDGE OF HIGH PRESSURE OVER THE FORECAST AREA WILL SHIFT TO THE
EAST DURING THE DAY ON TUESDAY AS A COLD FRONT APPROACHES FROM THE
WEST. TEMPERATURES WILL BE WELL ABOVE NORMAL WITH STRONG
SOUTHWESTERLY FLOW AHEAD OF THE FRONT AND H850 TEMPERATURES
APPROACHING 2 STD DEVIATIONS ABOVE NORMAL, BUT WILL BE SOMEWHAT
STUNTED DUE TO INCREASED MID AND UPPER LEVEL CLOUD COVER. GUIDANCE
CONTINUES TO SHOW NEAR RECORD TEMPERATURES (78 DEGREES FOR
PITTSBURGH) FOR TUESDAY, BUT THE BEST MATCHING ANALOGS AND LOCAL
STUDIES SUGGEST TEMPERATURES IN THE LOW TO MID 70S IN GENERAL. IF
CLOUD COVERAGE DOES END UP LESS THAN EXPECTED, RECORD TEMPERATURES
WOULD NOT BE OUT OF THE QUESTION, ESPECIALLY SINCE THE RECORD FOR
NEXT TUESDAY IS SEVERAL DEGREES LOWER THAN DATES BOTH BEFORE AND
AFTER. MODELS ARE IN RELATIVELY GOOD AGREEMENT WITH TIMING FRONTAL
PASSAGE TUESDAY EVENING SO POPS WERE INCREASED THEN AND OVERNIGHT
TO BE MORE IN LINE WITH OPERATIONAL MODELS AND ENSEMBLE GUIDANCE.
OTHERWISE, NO CHANGES WERE MADE TO THE INHERITED FORECAST.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
AN APPROACHING COLD FRONT WILL RESULT IN INCREASING CLOUD
COVERAGE OVERNIGHT...HOWEVER...NO SIGNIFICANT WEATHER IS EXPECTED TO
ACCOMPANY THE FRONTAL PASSAGE. WINDS WILL INCREASE OUT OF THE
WEST...BUT VFR CONDITIONS ARE EXPECTED TO PERSIST THROUGH THE
DURATION OF THE TAF PERIOD

OUTLOOK.../SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS ARE EXPECTED TO PERSIST THROUGH EARLY NEXT WEEK.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.

&&

$$

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