264
FXUS02 KWBC 130700
PMDEPD
EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
200 AM EST WED NOV 13 2024
VALID 12Z SAT NOV 16 2024 - 12Z WED NOV 20 2024
..OVERVIEW
TROUGHING OVER THE WEST BY THIS COMING WEEKEND WILL SPLIT SENDING
NORTHERN STREAM ENERGY THROUGH THE NORTHERN PLAINS/UPPER MIDWEST,
WHILE SOUTHERN STREAM ENERGY DROPS SOUTH AND THEN EASTWARD EARLY
NEXT WEEK. THIS SHOULD HELP INDUCE CYCLOGENESIS IN THE LEE OF THE
ROCKIES WITH A MODESTLY DEEP STORM EJECTING NORTHEASTWARD THROUGH
THE CENTRAL U.S. NEXT TUESDAY AND WEDNESDAY. THE PATTERN WOULD
SUPPORT HEAVY RAINFALL POTENTIAL FROM THE SOUTH-CENTRAL PLAINS INTO
THE MISSISSIPPI VALLEY BY LATE THIS WEEKEND INTO EARLY NEXT WEEK,
WITH SOME SNOW POSSIBLE ON THE BACKSIDE OF THE LOW DEPENDING ON
COLD AIR FILTERING IN BEHIND THIS SYSTEM. ANOTHER ATMOSPHERIC RIVER
WILL BRING A ROUND OF HEAVY RAIN AND MOUNTAIN SNOWS TO THE PACIFIC
NORTHWEST THIS WEEKEND. THIS SHOULD RELOAD AND HELP DEEPEN MEAN
TROUGHING OVER THE WEST RESULTING IN A RATHER ACTIVE AND AMPLIFIED
PATTERN ACROSS THE CONUS BY NEXT WEEK WITH STRONG TROUGHING
SHIFTING THROUGH THE CENTRAL U.S. AND RIDGING OVER THE EAST AND
WEST COASTS. MEANWHILE, GUIDANCE CONTINUES TO SUGGEST SOME SORT OF
TROPICAL DEVELOPMENT EMERGING OUT OF THE CARIBBEAN AND INTO THE
SOUTHERN GULF OF MEXICO NEXT WEEK.
..GUIDANCE/PREDICTABILITY ASSESSMENT
THE GUIDANCE SHOWS GOOD AGREEMENT ON THE OVERALL LARGE SCALE
PATTERN ACROSS THE CONUS FOR THE UPCOMING MEDIUM RANGE PERIOD, BUT
PLENTY OF UNCERTAINTY IN THE DETAILS AND EVOLUTION OF INDIVIDUAL
SYSTEMS. THE MAIN AREA OF UNCERTAINTY CONTINUE SOT LIE WITH THE
DEEP WESTERN TROUGH WHICH MAY BRIEFLY CLOSE OFF A LOW IN/AROUND
NORTHWEST MEXICO BEFORE IT MOVES EASTWARD. THE MODELS SHOW BETTER
AGREEMENT THIS SHOULD TRACK NORTHEASTWARD INDUCING STRONG SURFACE
LOW PRESSURE THAT TRACKS THROUGH THE CENTRAL U.S. NEXT WEEK. MORE
UNCERTAINTY SURROUNDS THE NEXT SHORTWAVE INTO THE WEST WHICH SHOULD
RELOAD AND DEEPEN THE MEAN WESTERN TROUGH LEADING TO SOME
DIFFERENCES IN EXACTLY HOW ENERGY GETS INCORPORATED INTO THE TROUGH
AND HOW QUICKLY IT MOVES EASTWARD. FARTHER SOUTH, THE GUIDANCE HAS
BEEN TRENDING TOWARDS AN EMERGING TROPICAL THREAT OUT OF THE
CARIBBEAN INTO THE SOUTHERN GULF, BUT STILL QUITE A BIT OF
UNCERTAINTY ON POTENTIAL IMPACTS TO PARTS OF THE SOUTHEAST. SEE
TROPICAL OUTLOOKS FROM THE NATIONAL HURRICANE CENTER FOR THE LATEST
INFORMATION ON THIS POTENTIAL.
WAS ABLE TO UTILIZE A GFS/ECMWF/CMC BLEND FOR THE FIRST FEW DAYS
OF THE WPC PROGS TONIGHT. QUICKLY TRENDED MORE TOWARDS THE ENSEMBLE
MEANS LATE PERIOD TO ACCOUNT FOR INCREASING UNCERTAINTY WITH THE
WEST TO CENTRAL U.S. TROUGH. THIS GENERALLY MAINTAINS GOOD
CONTINUITY WITH THE PREVIOUS WPC FORECAST, BUT MAYBE A LITTLE
QUICKER WITH SURFACE LOW/FRONTAL PROGRESSION THROUGH THE PLAINS-
MISSISSIPPI VALLEY.
..WEATHER/HAZARDS HIGHLIGHTS
PRECIPITATION SHOULD INCREASE IN INTENSITY AND COVERAGE ACROSS
PARTS OF THE FOUR CORNERS REGION INTO THE SOUTH- CENTRAL
PLAINS/MISSISSIPPI VALLEY BEGINNING THIS WEEKEND, WITH THE OVERALL
SETUP SUPPORTING A HEAVY RAIN THREAT FROM THE SOUTH-CENTRAL PLAINS
INTO THE MIDDLE MISSISSIPPI VALLEY SUNDAY-MONDAY. EXACT AMOUNTS,
LOCATION, AND IMPACTS REMAIN VERY UNCERTAIN BUT THERE IS ENOUGH
SIGNAL TO INTRODUCE A BROAD MARGINAL RISK ON THE DAY 5/SUNDAY
EXCESSIVE RAINFALL OUTLOOK FROM NORTHERN TEXAS INTO OKLAHOMA.
DEPENDING ON COLD AIR FILTERING IN BEHIND THE SYSTEM, SOME SNOW MAY
BE POSSIBLE ACROSS THE ROCKIES INTO THE NORTHERN PLAINS EARLY-MID
NEXT WEEK. GENERALLY WET CONDITIONS IS EXPECTED TO ACCOMPANY THE
COLD FRONT LATE PERIOD AS IT PUSHES INTO THE EAST-CENTRAL STATES
AND GREAT LAKES. OUT WEST, ANOTHER ATMOSPHERIC RIVER WILL SUPPORT
HEAVY RAIN AND MOUNTAIN SNOWS ACROSS THE PACIFIC NORTHWEST THIS
WEEKEND. MARGINAL RISKS ARE HIGHLIGHTED ON BOTH THE DAY 4 AND 5
EROS. MOISTURE FROM WHATEVER TROPICAL THREAT EMERGES OUT OF THE
CARIBBEAN MAY BEGIN IMPACTING PARTS OF FLORIDA MID NEXT WEEK, BUT
THERE IS A LOT OF UNCERTAINTY IN EXACT IMPACTS AND AMOUNTS FROM
THIS. BUT THIS WILL NEED TO CONTINUE TO BE WATCHED.
ABOVE NORMAL TEMPERATURES WILL PROGRESS EASTWARD WITH TIME FROM
THE CENTRAL U.S. SATURDAY, ENVELOPING THE EAST BY SUNDAY INTO
MONDAY. DAYTIME HIGHS COULD BE 10-15 DEGREES ABOVE NORMAL IN SOME
SPOTS. OUT WEST, TEMPERATURES WILL TREND MUCH COOLER WITH TIME AS
UPPER TROUGHING AMPLIFIES OVER THE REGION AND PERSISTS INTO NEXT
WEEK.
SANTORELLI
ADDITIONAL 3-7 DAY HAZARD INFORMATION CAN BE FOUND ON THE WPC MEDIUM
RANGE HAZARDS OUTLOOK CHART AT:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP
WPC MEDIUM RANGE 500MB HEIGHTS, SURFACE SYSTEMS, WEATHER GRIDS,
QUANTITATIVE PRECIPITATION FORECAST (QPF), EXCESSIVE RAINFALL
OUTLOOK (ERO), WINTER WEATHER OUTLOOK (WWO) PROBABILITIES, HEAT
INDICES, AND KEY MESSAGES CAN BE ACCESSED FROM:
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST500_WBG.GIF
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST_WBG_CONUS.GIF
HTTPS://WWW.WPC.NCEP.NOAA.GOV/5KM_GRIDS/5KM_GRIDSBODY.HTML
HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/DAY4-7.SHTML
HTTPS://WWW.WPC.NCEP.NOAA.GOV/#PAGE=ERO
HTTPS://WWW.WPC.NCEP.NOAA.GOV/WWD/PWPF_D47/PWPF_MEDR.PHP?DAY=4
HTTPS://WWW.WPC.NCEP.NOAA.GOV/HEAT_INDEX.SHTML
HTTPS://WWW.WPC.NCEP.NOAA.GOV/#PAGE=OVW
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page