609
FXUS02 KWBC 040558
PMDEPD
EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
158 AM EDT FRI OCT 4 2024
VALID 12Z MON OCT 07 2024 - 12Z FRI OCT 11 2024
...POTENTIALLY HAZARDOUS HEAT WILL PERSIST ACROSS THE SOUTHWEST
THROUGH MONDAY...
...CHANCES FOR HEAVY RAINFALL ACROSS THE FLORIDA PENINSULA WILL
INCREASE INTO NEXT WEEK...
..OVERVIEW
THE UPPER PATTERN OVER THE CONUS NEXT WEEK SHOULD SETTLE INTO A
SLOWER-EVOLVING PATTERN DOMINATED BY MAINLY LARGE SCALE FEATURES.
AN UPPER RIDGE SLOWING MOVING FROM THE WESTERN TO CENTRAL U.S. WILL
SUPPORT MUCH ABOVE NORMAL TEMPERATURES WHILE A TROUGH SETTLING
OVER THE EAST (ANCHORED BY AN UPPER LOW THAT MAY TRACK OVER OR NEAR
NEW ENGLAND) WILL BRING A COOLER TREND. THE LEADING EDGE OF A
PACIFIC TROUGH WILL PRODUCE GRADUAL HEIGHT FALLS OVER THE PACIFIC
NORTHWEST INTO LATE NEXT WEEK AND BRING SOME PRECIPITATION TO THE
NORTHERN PARTS OF THE REGION. FARTHER SOUTH, EXPECT THE MAIN
RAINFALL FOCUS OVER THE LOWER 48 TO BE OVER PARTS OF FLORIDA, DUE
TO THE COMBINATION OF ABUNDANT TROPICAL MOISTURE IN ADDITION TO ONE
OR MORE GULF OF MEXICO SURFACE FEATURES AND A FRONT DRAPED ACROSS
THE PENINSULA.
..GUIDANCE/PREDICTABILITY ASSESSMENT
GUIDANCE CONTINUES TO SHOW SOME TYPICAL DIFFERENCES IN THE DETAILS
FOR THE EVOLUTION OF THE UPPER TROUGH SETTLING OVER THE EAST AND
THE ANCHORING LOW. SOME QUESTION ON TIMING AND PLACEMENT OF THE
UPPER LOW MID TO LATE WEEK, BUT A GENERAL MODEL COMPROMISE SEEMED
TO PROVIDE A GOOD MIDDLE GROUND SOLUTION. TIMING OF THE NEXT TROUGH
INTO THE WEST AND WEAKER SHORTWAVES AHEAD OF IT BECOMES UNCERTAIN
LATE NEXT WEEK. THE WPC FORECAST USED GENERAL MODEL COMPROMISE
THROUGH THE PERIOD, WITH MORE ENSEMBLE MEAN INCLUSION LATE PERIOD.
THE MAIN FEATURE OF INTEREST DURING THE PERIOD THOUGH IS STILL
EVOLUTION OF POSSIBLE TROPICAL FEATURES IN THE GULF OF MEXICO.
EARLY WEEK, ONE WAVE MAY TRACK INTO THE CENTRAL/EAST-CENTRAL GULF
WHILE ANOTHER FEATURE (POSSIBLE REMNANT ENERGY FROM ELEVEN-E IN THE
EAST PACIFIC) MAY EVOLVE OVER THE WESTERN GULF. MODELS AND
ENSEMBLES HAVE SHOWN SOME IMPROVEMENT IN THE SIGNAL FOR THESE
FEATURES TO PHASE EARLY NEXT WEEK AS THEY APPROACH FLORIDA AND
INTERACT WITH A WAVY FRONT ACROSS FLORIDA INTO THE GULF. THROUGH
THE 12Z/18Z GUIDANCE, MODELS WERE IN AGREEMENT WITH THIS EVOLUTION
BUT SHOWED SOME SIGNIFICANT DIFFERENCES IN TIMING. THE 00Z GFS
TONIGHT CAME IN QUITE SUPPRESSED TO THE SOUTH WITH LITTLE TO NO
TROPICAL DEVELOPMENT. UNCERTAINTY IN ANY SORT OF TROPICAL
DEVELOPMENT ACROSS THE GULF REMAINS VERY HIGH. PLEASE CONSULT THE
NHC OUTLOOKS FOR THE LATEST INFORMATION ON FEATURES OF INTEREST
OVER THE GULF.
..WEATHER/HAZARDS HIGHLIGHTS
THE HEAVIEST RAINFALL POTENTIAL FOR NEXT WEEK WILL BE OVER THE
FLORIDA PENINSULA, WITH SLOW- MOVING LOW PRESSURE OVER THE GULF OF
MEXICO ALONG WITH A WAVY FRONT DRAPED OVER THE STATE AND A BROAD
AREA OF ANOMALOUS MOISTURE EXTENDING OVER/EAST OF THE GULF. THERE
IS STILL A FAIR AMOUNT OF UNCERTAINTY FOR DETAILS THOUGH. ENHANCED
MOISTURE AND POTENTIALLY HEAVY RAINFALL IS EXPECTED THROUGH THE
WEEK ACROSS AT LEAST THE SOUTHERN HALF OF FLORIDA, AND THIS IS
SUPPORTED FOR NOW WITH MARGINAL RISKS ON THE DAY 4/MONDAY AND DAY
5/TUESDAY EXCESSIVE RAINFALL OUTLOOKS. PRECIPITATION MAY BE FURTHER
ENHANCED BY ANY POSSIBLE TROPICAL SYSTEM APPROACH, BUT REGARDLESS,
MODELS AGREE ON A MULTI-DAY HEAVY RAINFALL SIGNAL ACROSS PARTS OF
FLORIDA.
ELSEWHERE, THE FRONTAL SYSTEM INTO THE NORTHEAST ON MONDAY MAY
GENERATE RAINFALL WHICH SHOULD SHIFT OUT OF THE REGION WITH THE
COLD FRONT BY MID WEEK. A MEAN FRONTAL ZONE WITH ONE OR MORE
EMBEDDED WAVES SHOULD REACH NEAR THE NORTHERN PACIFIC NORTHWEST BY
EARLY-MID WEEK, PRODUCING SOME PERIODS OF LIGHT TO LOCALLY MODERATE
RAIN AND NON- ZERO CHANCES OF SNOW IN THE HIGHEST ELEVATIONS.
THE STRONG AND PERSISTENT WESTERN-CENTRAL U.S. UPPER RIDGE WILL
PROMOTE AN EXTENDED PERIOD OF WELL ABOVE NORMAL TEMPERATURES OVER
THAT PART OF THE COUNTRY. GRADUAL EASTWARD DRIFT OF THE RIDGE AXIS
WILL SHIFT THE HIGHEST ANOMALIES FROM THE WEST ON MONDAY, WITH SOME
HIGHS AT LEAST 10-15F ABOVE NORMAL, MORE INTO THE PLAINS BY
TUESDAY-THURSDAY WHEN SOME NORTHERN LOCATIONS COULD REACH 20-25F
ABOVE NORMAL. EXPECT NUMEROUS DAILY RECORDS FOR WARM MINIMUM AND
MAXIMUM TEMPERATURES, ESPECIALLY OVER THE SOUTHWEST THROUGH MONDAY.
HEIGHT FALLS SLOWLY PUSHING IN OVER THE WEST COAST WILL SUPPORT A
TREND TOWARD NEAR NORMAL TEMPERATURES BY WEDNESDAY OR THURSDAY.
TEMPERATURES OVER MOST OF THE EAST SHOULD MODERATE STARTING MONDAY
TO NEAR OR SOMEWHAT BELOW NORMAL AS UPPER TROUGHING SETS UP NEAR
THE EAST COAST. THIS MAY LEAD TO FROST/FREEZE CONCERNS ACROSS
PORTIONS OF THE UPPER GREAT LAKES REGION AND INTERIOR NORTHEAST,
WITH THE TIMING AROUND THE MEDIAN TO A BIT LATE FOR THE FIRST
FROST/FREEZE OF THE SEASON.
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